Towards a taxonomy of sexuality following traumatic brain injury: A pilot exploratory study using cluster analysis

Abstract

INTRODUCTION:

Clinicians need to understand the heterogeneity of sexual problems following traumatic brain injury (TBI) for their adequate identification and treatment.

OBJECTIVE:

To systematically identify groups of individuals with TBI showing similar patterns of sexual functioning.

METHODS:

Forty-two individuals with TBI with a mean age of 37.9 years (SD = 9.7) and an average of 3.3 years post-injury (SD = 4.3). We included four primary measures in the cluster analysis (sexual quality of life questionnaire, sexual desire inventory, generalized anxiety disorder scale, and the patient health questionnaire for depression) and two secondary measures for cluster validation (post-concussion symptom scale and dysexecutive questionnaire).

RESULTS:

A hierarchical cluster analysis using the Ward method revealed the existence of two groups of individuals with TBI: a) with sexual problems who were older, showed lower levels of sexual quality of life and sexual desire, with significant symptoms of anxiety and depression, and b) without sexual problems who were younger, showed high levels of sexual quality of life and sexual desire, as well as low complaints of anxiety and depression.

CONCLUSIONS:

Clinicians must be more proactive in assessing sexual concerns, mostly when emotional and cognitive difficulties are present in older individuals with TBI, regardless of gender, chronicity and injury severity.

Keywords

Neurosexuality cluster analysis traumatic brain injury sexual quality of life sexual desire depression anxiety

1 Introduction

It is estimated that every year, traumatic brain injury (TBI) requiring medical attention approaches 3.5 million and contributes to 30.5% of all injury-related deaths in the USA (Diaz-Arrastia & Kenney, 2015). Most of the injuries correspond to mild TBIs (80%), with a worldwide estimated incidence of 100–150 per 100 000 people (Katz, Cohen, & Alexander, 2015). However, advances in TBI treatment and education for prevention have contributed to a trend in the reduction of fatalities. As TBIs are more common in younger and middle-aged groups, TBI translates into productivity loss, medical cost and disability, with approximately 1.1% of the US population living with a TBI-related disability (Faul & Coronado, 2015).

Post-TBI disability involves physical changes (Bramlett & Dietrich, 2015), changes in social roles (Pearce, Cartwright, Cocks, & Whitworth, 2016; Saxton, Younan, & Lah, 2013), cognitive (Carroll et al., 2014) and emotional problems (Bhalerao et al., 2013). In addition, individuals with TBI report changes in their sexuality, such as reduced sexual desire and arousal (Hanks, Sander, Millis, Hammond, & Maestas, 2013), reduction in orgasm (Sander et al., 2012), body image difficulties (Hibbard, Gordon, Flanagan, Haddad, & Labinsky, 2000), and diminished sexual quality of life (Moreno, Arango Lasprilla, & McKerral, 2015), among others. Their spouses/partners also experience poorer sexual functioning (20%) and dissatisfaction with their sexuality (44%) (Sander et al., 2016). As such, the sexual problems present in the individual with TBI can affect their partners’ sexual lives (Downing & Ponsford, 2016). Theoretically, these difficulties have been summarized within a biopsychosocial framework (Bivona et al., 2016; Moreno, Arango-Lasprilla, Gan, & McKerral, 2013). Clinically, there is an increasing need to understand the heterogeneity in the presentation of sexual problems post-TBI. Understanding the factors that may be associated with sexual problems following a TBI can be useful to focus interventions in individuals who are more likely to present with sexual dysfunction. Indeed, some individual characteristics (e.g., age, the presence of emotional complaints, female gender) and injury characteristics (e.g., time post injury and the severity of the injury) have been documented as associated with post-TBI sexual problems. A study showed that being depressed and older in age, at shorter time post-injury, and less independent in activities of daily living significantly predicted poorer sexual functioning (Ponsford, Downing, & Stolwyk, 2013). The results of another study show that older persons, females, and individuals with more severe injuries appear to be at greater risk of developing sexual dysfunction following TBI (Sander et al., 2013).

The rehabilitation of individuals with TBI involves a transdisciplinary approach aiming to the successful community integration. Part of the rehabilitation process involves sexual rehabilitation (Bélanger, 2009) and individuals with TBI want more openness to discuss their sexual concerns (Moreno, Gan, Zasler, & McKerral, 2015). Thus, healthcare professionals will advance in their optimal care provision if they are able to successfully identify individuals with TBI whose clinical characteristics can indicate the possible presence of sexual problems. Such identification requires the description of specific groups of individuals with TBI sharing relevant characteristics that can be appreciated in a clinical assessment. To our knowledge, previous studies have not explored the identification of groups of individuals with TBI based on their sexual profiles and relevant clinical characteristics for sexual functioning. The current pilot exploratory study aimed to systematically identify groups of individuals with mild, moderate or severe TBI that show similar patterns of sexual functioning using cluster analysis based on their: a) age, b) sexual quality of life, c) sexual desire, d) anxiety, and e) depressive complaints. Based on the heterogeneity of sexual difficulties following TBI (Moreno et al., 2013), we did not have a prediction regarding the number of groups that would result, as cluster analysis is an exploratory technique used to generate hypotheses (Malec, Machulda, & Smigielski, 1993).

2 Methods

2.1 Participants

The sample consisted of 42 community-dwelling individuals with TBI who were recruited from a major social and vocational rehabilitation center in Montreal. They were recruited based on the following inclusion criteria: a) individuals who have sustained a mild (Glasgow Coma Scale (GCS) score 13–15), moderate (GCS score 9–12) or severe TBI (GCS score 3–8) according to the TBI guidelines of the Québec Ministry of Health (Gouvernement du Québec/Ministère de la Santé et des Services Sociaux & Société de l’assurance automobile du Québec, 2005); b) six or more months post-injury; c) 18 years or older; d) reporting to be able to read, write, and speak either French or English. Based on medical records and self-report, individuals with TBI were excluded if they presented: a) a history of learning or language disability, including aphasia or communication disorders; b) pre-injury psychiatric, sexual or neurological disorders; and c) a diagnosis of substance abuse or substance dependence according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (American Psychiatric Association. & Task Force on DSM-IV, 2000). Participants were excluded based on substance use or dependency because there is evidence showing that drug abuse can affect different aspects of sexuality. For instance, women who consume crack cocaine present sexual dysfunction (Henderson, Boyd, & Whitmarsh, 1995). More importantly, we also wanted to control this variable because it has been noted as a limitation in studies of sexuality and TBI, particularly in the context of risky sexual behavior (Kramer, Nelson, & Li, 1993). Individuals with TBI were on average 3.3 years post-injury (SD = 4.3). The cause of the injury was predominantly associated with a motor vehicle accident (42.9%). Glasgow coma scale at admission was on average 12.5 (SD = 3.6), with a loss of consciousness of a mean of 5.8 hours (SD = 28.8), as documented in medical records. Most of the participants had sustained a mild TBI (66.8%), with 42% of them meeting criteria for “complex” mild TBI (e.g., with positive brain abnormality on CT-scan). Positive findings on CT scan or MRI suggesting a brain injury were documented in 59.5% of the entire TBI sample (see Table 1).

Table 1
Sociodemographic and clinical characteristics of individuals with TBI (N = 42)

N (%) Mean (SD)

Gender

Male 19 (45.2%)

Female 23 (54.8%)

Race and ethnicity

White 38 (90.5%)

Hispanic 4 (9.5%)

Work status

Full-time 16 (38.1%)

Part-time 7 (16.7%)

Unemployed 19 (45.2%)

Relationship status

Single 26 (61.9%)

Married 4 (9.5%)

Separated 0 (0%)

Divorced 2 (4.8%)

Common-law 10 (23.8%)

Widow/Widower 0 (0%)

Severity of the injury

Mild TBI 28 (66.8%)

Moderate TBI 3 (7.1%)

Severe TBI 8 (19%)

Missing 3 (7.1%)

Age (Years) 37.9 (9.7)

Education (Years) 12.8 (3.3)

GCS score 12.5 (3.6)

Years post- injury 3.3 (4.3)

Length of LOC (Hours) 5.8 (28.8)

	N (%)	Mean (SD)
Gender
Male	19 (45.2%)
Female	23 (54.8%)
Race and ethnicity
White	38 (90.5%)
Hispanic	4 (9.5%)
Work status
Full-time	16 (38.1%)
Part-time	7 (16.7%)
Unemployed	19 (45.2%)
Relationship status
Single	26 (61.9%)
Married	4 (9.5%)
Separated	0 (0%)
Divorced	2 (4.8%)
Common-law	10 (23.8%)
Widow/Widower	0 (0%)
Severity of the injury
Mild TBI	28 (66.8%)
Moderate TBI	3 (7.1%)
Severe TBI	8 (19%)
Missing	3 (7.1%)
Age (Years)		37.9 (9.7)
Education (Years)		12.8 (3.3)
GCS score		12.5 (3.6)
Years post- injury		3.3 (4.3)
Length of LOC (Hours)		5.8 (28.8)

Note: LOC, loss of consciousness; GCS, Glasgow Coma Scale.

2.2 Procedure

The Research Ethics Board (REB) of the Center for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR) approved the current study. Following an invitation on a call, 108 individuals with TBI accepted to participate in the study. The research team mailed the questionnaires and consent forms. Participants completed a questionnaire that included medical and sociodemographic information (e.g., age, gender, race/ethnicity, years of education, relationship, and status). With the participant’s authorization, pre-injury and injury related data were extracted from their medical records (e.g., GCS score, number of years post-injury, and presence/absence of neuroradiological abnormalities). Once completed, the consent form and the questionnaire with an identification code were sent independently. Forty-two individuals with TBI successfully completed and returned the documents using prepaid envelopes, with a return rate of 38.9%. One individual had to be excluded from the study for incomplete data in one of the primary measures.

To facilitate the contact with the participants, we provided a telephone number and an email to respond to any questions. The participants received a financial compensation of 15 Canadian dollars for their participation after returning their questionnaires and consent forms.

2.3 Instruments

2.3.1 Main measures

Four primary measures were used to assess the sexuality of individuals with TBI and their emotional symptoms post-TBI.

2.3.1.1 Sexual Quality of Life Questionnaire. The Sexual Quality of Life Questionnaire was developed to evaluate the impact of sexual dysfunction on quality of life, specifically to assess sexual confidence, emotional well-being, and relationship issues (e.g., “When I think about my sexual life, I feel frustrated”, “I try to avoid sexual activity”). The Sexual Quality of Life Questionnaire comes in male (11 items) and female forms (18 items), each with a 6-point response scale (completely agree to completely disagree). With items scored 1–6, higher scores indicate better functioning. It has been used to assess sexual quality of life with good internal consistency (Cronbach’s α= 0.95) and convergent validity (Abraham, Symonds, & Morris, 2008; Symonds, Boolell, & Quirk, 2007). Regarding the discriminant validity, the Sexual Quality of Life Questionnaire differentiates individuals with TBI from healthy controls (Moreno, Arango Lasprilla, et al., 2015). In the current study, the internal consistency of the Sexual Quality of Life Questionnaire was acceptable (Cronbach’s α= 0.71).

2.3.1.2 Sexual Desire Inventory (SDI-2). The SDI-2 is an 14-item self-report measure of sexual desire to assess dyadic sexual desire and solitary sexual desire (Spector, Carey, & Steinberg, 1996). The participants must rate how strong their desire would be in a variety of sexual situations and they are asked to use the last month as a reference (e.g., “When you first see an attractive person, how strong is your sexual desire?”; “How strong is your desire to engage in sexual activity with a partner?”). Most respondents complete the scale in 5 minutes and each item is rated in an 8-point scale. Scores are sums across items, with higher scores reflecting stronger sexual desire (King & Allgeier, 2000; Ortega, Zubeidat, & Sierra, 2006). The scale has excellent psychometric properties and it has been used to measure sexual desire in the general population and in clinical samples, as well as in younger and older samples, individuals and couples (Davis, 1998). We used the total score as the variable of analysis. In the current study, the internal consistency of the SDI-2 was good (Cronbach’s α= 0.88).

2.3.1.3 Generalized Anxiety Disorder Scale (GAD-7). The GAD-7 is a self-administered examination used to identify probable cases of generalized anxiety disorders (Spitzer, Kroenke, Williams, & Lowe, 2006). Each of the 7 items are scored from 0 to 3 (“not at all” to “nearly every day”), depending on how often the respondent has been bothered by each problem over the past 2 weeks (e.g., “Being so restless that it is hard to sit still”). The response scores are totaled, and the total score ranges from 0 to 21, with higher scores reflecting higher levels of anxiety. The GAD-7 is a valid and reliable screening tool for generalized anxiety disorders and has been translated and adapted to several languages (Delgadillo et al., 2012; Donker, van Straten, Marks, & Cuijpers, 2011; García-Campayo et al., 2010; Lowe et al., 2008; Ruiz et al., 2011; Sidik, Arroll, & Goodyear-Smith, 2012; Swinson, 2006; Wild et al., 2013) including French (Barthel, Barkmann, Ehrhardt, & Bindt, 2014). The GAD-7 can discriminate individuals with TBI and healthy controls (Moreno & McKerral, 2016). In the present study and its internal consistency was excellent (Cronbach’s α= 0.90).

2.3.1.4 Patient Health Questionnaire (PHQ-9). The PHQ is a self-administered examination used to diagnose mental disorders. The PHQ-9 is the module of the PHQ that specifically evaluates depression. The evaluation consists of 9 items that reflect typical symptoms of depression, and directs the respondent to indicate a response from 0 to 3 (“not at all” to “nearly every day”), depending on how often they have been bothered by each problem over the past 2 weeks (e.g., “Feeling tired or having little energy”). The response scores are totaled, and the total score ranges from 0 to 27, with higher scores reflecting higher levels of depression. The PHQ-9 is a valid and reliable screening tool for detecting major depressive disorder in individuals with TBI (Cook et al., 2011; Fann et al., 2005). The PHQ-9 discriminates between individuals with TBI and healthy controls (Moreno & McKerral, 2016). In the current study, the internal consistency of the PHQ-9 was good (Cronbach’s α= 0.88).

2.3.2 Secondary measures

Two instruments were used to assess the external validity of the clusters.

2.3.2.1 Post-Concussion Symptom Scale (PCSS). The PCSS is a 22-item scale designed to measure the severity of symptoms in the acute phase of recovery from concussion (Lovell et al., 2006). Respondents rate the severity of each symptom (e.g. headache, sensitivity to light, difficulty remembering) compared to their pre-injury state on a 7-point scale with 0 (asymptomatic) and 6 (severely symptomatic). Higher scores indicate worse functioning. It has good internal consistency (Cronbach’s α= 0.87) (Valovich & Leach, 2012). The total score was used in this study. In the current study, the internal consistency of the PCSS was excellent (Cronbach’s α= 0.96).

2.3.2.2 Dysexecutive Questionnaire (DEX). The DEX from the Behavioural Assessment of the Dysexecutive Syndrome (BADS) is a 20-item questionnaire sampling many of the symptoms associated with executive impairment and emotional problems after neuropathology, such as impulsivity, inhibition control, monitoring, and planning (Bodenburg & Dopslaff, 2008; Shinagawa et al., 2007). It is available in two forms (patient and significant other). Items are rated on a 5-point scale from 0 to 4 (“never” to ”very often”). It is sensitive to executive dysfunction (Bennett, Ong, & Ponsford, 2005) and its psychometric properties have been demonstrated cross-culturally (Barker, Morton, Morrison, & McGuire, 2011; Pedrero-Perez et al., 2011; Simblett & Bateman, 2011). The total scale score of the patient questionnaire was used in this study. In the current study, the internal consistency of the DEX was excellent (Cronbach’s α= 0.96).

2.4 Statistical analyses

Statistical analyses were conducted with IBM SPSS version 21 (IBM, 2012). A hierarchical cluster analysis was performed using the Ward method to classify individuals with TBI based on the variables of interest for sexual functioning (age, sexual quality of life, sexual desire, depressive and anxiety complaints). Squared Euclidian distances were used as the metric (Allen & Goldstein, 2013). The dendogram, the agglomeration schedule, and the interpretability of the cluster solution indicated that two different clusters provided a suitable representation of the data.

Later, we explored the validity of the clusters comparing the demographic and clinical characteristics of individuals with TBI using t-tests for continuous variables and χ² tests for nominal variables, taking into account statistical significance at an alpha level of 0.05 (Rapkin & Luke, 1993).

3 Results

3.1 Cluster solution

Figure 1 shows a Ward’s method cluster dendogram with the two clusters.

Fig.1

Ward’s method cluster dendogram.

There were significant differences between the two clusters in terms of age, sexual quality of life, sexual desire, depressive, and anxiety complaints (Table 2).

Table 2

Differences between the two clusters

Measure	Cluster 1		Cluster 2
	TBI without sexual		TBI with sexual
	problems (n = 21)		problems (n = 20)
	M	SD	M	SD	df	t	p	Cohen’s d
Age	31.8	6.5	44.5	8.4	39	–5.4	0.00001	1.69
SQoL	91.9	13.6	57.7	18.4	39	6.7	0.0001	2.11
SDI-2	68.6	14.5	55.1	22.8	39	2.2	0.029	0.71
GAD-7	3.8	3.2	10	5.2	39	–4.6	0.00004	1.43
PHQ-9	5.3	3.7	12.7	5.5	39	–4.9	0.00001	1.57

Note: SQoL, Sexual Quality of Life; SDI-2, Sexual Desire Inventory; GAD-7, Generalized Anxiety Disorder Scale, PHQ-9, Patient Health Questionnaire.

3.1.1 Cluster 1 (TBI without sexual problems)

Individuals with TBI in the first cluster were younger (thirty’s on average), showed high levels of sexual quality of life and sexual desire, as well as low complaints of anxiety and depression. As such, this cluster has been named “TBI without sexual problems”. The first cluster corresponded to 51.2% of individuals with TBI.

3.1.2 Cluster 2 (TBI with sexual problems)

Individuals with TBI in the second cluster were older (mid-forty’s on average), showed lower levels of sexual quality of life and sexual desire, with significant symptoms of anxiety and depression. As such, this cluster has been named “TBI with sexual problems”. A total of 48.8% of individuals with TBI were classified as belonging to this cluster.

3.2 Cluster validity

To verify the external validity of the clusters, the groups were compared in sociodemographic variables, clinical characteristics, and self-report of post-TBI symptoms. There was a statistically significant difference between cluster 1 (M = 13.6, SD = 15) and cluster 2 (M = 52.4, SD = 29.1) in the report of postconcussion symptoms, t (39) = –5.41, p < 0.05. The Cohen’s d statistic (1.67) indicates a large effect. In addition, there was a statistically significant difference between cluster 1 (M = 17.7, SD = 8.8) and cluster 2 (M = 28.6, SD = 13.8) in the report of dysexecutive symptoms, t (39) = –3.03, p < 0.05. The Cohen’s d statistic (0.94) indicates a large effect. However, there were no statistically significant differences between the groups in terms of gender, years of education, severity of the injury (as measured by the GCS), years after the injury, length of loss of consciousness, and presence/absence of neuroradiological findings post-injury (all p’s >0.05).

4 Discussion

The current pilot exploratory study identified groups of individuals with TBI based on their sexual profiles and relevant clinical characteristics for sexual functioning in a sample of individuals with mild, moderate or severe TBI. A hierarchical cluster analysis revealed the existence of two groups of individuals with TBI presenting with and without sexual problems. The groups were externally validated with the self-report of postconcussion (Mounce et al., 2013) and dysexecutive symptoms (Tate et al., 2014) that commonly affect individuals with TBI. The group presenting with sexual problems corresponds to 48.8% of the TBI sample. This percentage agrees with previous reports indicating that TBI impacts people’s sexuality, with 50 to 60% of persons reporting some level of disruption post-injury (Kreuter, Dahllof, Gudjonsson, Sullivan, & Siosteen, 1998; O’Carroll, Woodrow, & Maroun, 1991; Simpson, 2001). Interestingly, individuals with TBI belonging to the group with sexual problems were older (mid-forty’s), showed lower levels of sexual quality of life and sexual desire, and presented with significant symptoms of anxiety and depression. These findings correspond with previous studies with moderate to severe TBI large samples suggesting that depression (Sander et al., 2013) and being older in age predict poorer sexual functioning (Ponsford et al., 2013).

Some of the characteristics of our TBI sample could explain the differences with previous reports of risk factors for sexual problems. For instance, we did not find differences regarding the severity of the injury between the groups with and without sexual problems. Absence of differences regarding injury severity could be explained by the fact that most of our sample corresponded mainly to mild TBIs. Also, a study that included a large TBI sample ranging from 1 to 20 years post-injury suggests that a shorter time post-injury predicts sexual functioning (Ponsford et al., 2013). On average, individuals with TBI participating in the current pilot exploratory study were 3.3 years post-injury and this could be a reason for discrepant findings. Likewise, we did not find gender differences as documented in Sander et al. (2013)’s multicenter study, which included a sample of 73% males with moderate to severe TBI at one year post-injury. In our study, having more chronic injuries and a higher percentage of women (54.8%) could explain the divergences in the findings.

It is possible that post-TBI psychiatric morbidity has a negative impact on sexuality, as observed in the group of individuals with TBI with sexual problems. In the general population, depression has been associated with erectile dysfunction and premature ejaculation (Corona et al., 2015), and with hypoactive sexual desire in women (Malary, Khani, Pourasghar, Moosazadeh, & Hamzehgardeshi, 2015). Two meta-analytic studies showed that the prevalence of clinically significant anxiety (37%) (Osborn, Mathias, & Fairweather-Schmidt, 2016) and depression (38%) (Osborn, Mathias, & Fairweather-Schmidt, 2014) are common in individuals having sustained a TBI. Also, a longitudinal study conducted in a community-based sample of young, middle-aged, and older adults concluded that compared to non-injured participants, anxiety is more common than depression following a TBI, although comorbid anxiety and depression were present in 10% of individuals with TBI (Osborn, Mathias, Fairweather-Schmidt, & Anstey, 2016). In addition, older age was associated with an increased likelihood of anxiety problems after a TBI. The authors conclude that both conditions should be monitored and treated given their chronic nature. To treat depression and anxiety taking into account the presence of cognitive impairment observed mainly in moderate to severe TBI, adapted cognitive behavior therapy (Ponsford et al., 2016) and different pharmacological interventions have proven to be effective.

To our knowledge, this pilot exploratory study is the first to explore the existence of groups of individuals with TBI based on their sexual functioning using cluster analysis. Our findings imply the existence of at least two groups among individuals TBI based on their sexual functioning. The results have implications for clinical practice. When assessing emotional complaints and cognition, rehabilitation professionals must address sexual concerns with their clients. Particularly, when emotional and cognitive difficulties are present in older individuals with TBI, regardless of gender, chronicity and injury severity. Clinicians can be more proactive in addressing the sexuality of individuals with TBI given that they think that this discussion is appropriate (Moreno, Gan, et al., 2015). Early identification and treatment of sexual problems is critical. Leaving aside relevant concerns that affect the quality of life of individuals with TBI can contribute to the chronicity of sexual problems and reduce the probability of reaching the goal of community reintegration post-TBI. Broadly presented, identifying individuals at risk for persistent symptoms in an early stage reduces the negative consequences of late referral when residual impairments significantly affect community integration (e.g., return to work) (van der Naalt & Spikeman, 2015).

4.1 Limitations and future directions

The results of this pilot exploratory study should be interpreted with caution due to several limitations, mainly sampling and methodological concerns. Based on response rates, the sample for the current pilot study (38.9%) is not very different from other studies of sexuality post-TBI. For instance, response rates for studies of sexuality post-TBI, including multicenter studies, reached response rates between 20.9% and 28.9% (Hanks, Sander, Millis, Hammond, & Maestas, 2013; Sander et al., 2013). Regarding the sample size, the analytic strategy is an appropriate approach (cluster analysis) that does not suffer from a set of assumptions that is often unrealistic, as compared to some other multivariable techniques (Allen & Goldstein, 2013). Thus, the sample size is sufficient for a pilot exploratory study. Sample characteristics include underrepresentation of racial and ethnic minority groups. A study revealed that compared to white individuals with TBI, Hispanic and black individuals with TBI are significantly less likely to receive intensive rehabilitation (Meagher, Beadles, Doorey, & Charles, 2015). Thus, it can be possible that those disparities could lead to a higher prevalence and chronicity of sexual problems in racial and ethnic minority individuals with TBI. In addition, a total of 66.8% of our sample were in the mild TBI range, but there is some degree of generalization given the coincidence of our results with previous studies conducted with more severe and chronic injuries (Ponsford et al., 2013; Sander et al., 2013). Also, the results cannot be generalized to teenagers or older adults with TBI because our sample included exclusively young and middle-aged adults with TBI.

Methodological concerns include the analytic strategy and the study design. This pilot study was exploratory and transversal. Cluster analysis is an array of exploratory techniques to find structure on a data set, that is, to find a parsimonious solution with some explanatory validity. As such, cluster analysis is a tool to generate hypotheses and our results should be considered as suggestive and exploratory. However, external validation and convergent findings using different approaches point toward an initial taxonomy of sexuality following TBI. Future studies with larger TBI samples would allow replicating and identifying more refined cluster solutions based on sexual functioning. For instance, it is possible that sexual problems following TBI coexist with different clinical characteristics regarding injury severity and chronicity. Thus, exhaustive examination within groups of similar severity using cluster analysis would increase our understanding of sexuality by isolating clinical profiles based on sexual functioning and relevant clinical characteristics in mild, moderate, and severe TBIs. Prospective and longitudinal studies with larger samples could be useful in evaluating the stability of these clusters over time.

Despite these limitations, the current pilot exploratory study is original for several reasons:

Previous studies have not explored the identification of groups of individuals with TBI based on their sexual profiles and relevant clinical characteristics for sexual functioning.

Use of a novel methodology to identify groups of individuals with TBI. Cluster analysis has not been used before in studies about sexuality post-TBI. However, this analytic strategy offers a potential to move forward in the identification of different clinical profiles and offers an alternative to generate hypotheses regarding differential clinical characteristics in individuals with TBI. Readers will gain insight in the use of this strategy for secondary data analyses.

Triangulation and cross-validation purposes. Convergent scientific findings using different methodologies increase the validity of the results. The results are sound with the current literature about sexuality and TBI.

Contributes to clarify the heterogeneity of presentation of sexual problems post TBI. Sexual profiles are different in individuals with TBI. Having a comprehensive set of sound variables helps to depict a prototypical individual with TBI that could be identified as having sexual problems.

Facilitate clinical interpretation and rehabilitation: Describing groups of individuals with TBI with similar characteristics in their sexual profiles can help clinicians to target interventions based on those profiles.

4.2 Conclusions

The current pilot exploratory study identified two groups of individuals with TBI based on their sexual profiles and relevant clinical characteristics for sexual functioning. The group of individuals with TBI showing sexual problems was older, showed lower levels of sexual quality of life and sexual desire, with significant symptoms of anxiety and depression. On the contrary, the group of individuals with TBI without sexual problems was younger, showed high levels of sexual quality of life and sexual desire, as well as low complaints of anxiety and depression. Using cluster analysis as an exploratory technique, this is the first study depicting an initial taxonomy of sexuality in individuals with mild, moderate or severe TBI. This pilot exploratory study contributes to the understanding of the heterogeneity of sexual problems in individuals with TBI.

Conflict of interest

None to report.

Footnotes

Acknowledgments

The authors wish to thank the CRIR, CERNEC, and Faculté des études supérieures et postdoctorales de l’Université de Montréal (scholarships to J.A.M.), the CRLB for partial funding of this study (grant to M.M.), as well to the individuals with TBI who took part in the study.

References

Abraham

, Symonds

, & Morris

(2008). Psychometric validation of a sexual quality of life questionnaire for use in men with premature ejaculation or erectile dysfunction. The Journal of Sexual Medicine, 5(3), 595–601.

Allen

D. N.

, & Goldstein

(2013). Cluster analysis in neuropsychological research: Recent applications. New York, NY: Springer New York: Imprint: Springer.

American Psychiatric Association., & Task Force on DSM-IV. (2000). Diagnostic and statistical manual of mental disorders : DSM-IV-TR. 4th e éd.). Washington, DC: American Psychiatric Association.

Barker

L. A.

, Morton

, Morrison

T. G.

, & McGuire

B. E.

(2011). Inter-rater reliability of the Dysexecutive Questionnaire (DEX): Comparative data from non-clinician respondents-all raters are not equal. Brain Inj, 25(10), 997–1004. doi: 10.3109/02699052.2011.597046

Barthel

, Barkmann

, Ehrhardt

, & Bindt

(2014). Psychometric properties of the 7-item Generalized Anxiety Disorder scale in antepartum women from Ghana and Cote d’Ivoire. J Affect Disord, 169, 203–211. doi: 10.1016/j.jad.2014.08.004

Bélanger

(2009). Traumatic brain injury and sexual rehabilitation. Sexologies, 18, 83–85.

Bennett

, Ong

, & Ponsford

(2005). Measuring executive dysfunction in an acute rehabilitation setting: Using the dysexecutive questionnaire (DEX). Journal of the International Neuropsychological Society: JINS, 11(4), 376–385.

Bhalerao

S. U.

, Geurtjens

, Thomas

G. R.

, Kitamura

C. R.

, Zhou

, & Marlborough

(2013). Understanding the neuropsychiatric consequences associated with significant traumatic brain injury. Brain Inj, 27(7-8), 767–774. doi: 10.3109/02699052.2013.793396

Bivona

, Antonucci

, Contrada

, Rizza

, Leoni

, Zasler

N. D.

, & Formisano

(2016). A biopsychosocial analysis of sexuality in adult males and their partners after severe traumatic brain injury. Brain Inj, 30(9), 1082–1095. doi: 10.3109/02699052.2016.1165867

10.

Bodenburg

, & Dopslaff

(2008). The Dysexecutive Questionnaire advanced: Item and test score characteristics, 4-factor solution, and severity classification. The Journal of Nervous and Mental Disease, 196(1), 75–78.

11.

Bramlett

H. M.

, & Dietrich

W. D.

(2015). Long-term consequences of traumatic brain injury: Current status of potential mechanisms of injury and neurological outcomes. J Neurotrauma, 32(23), 1834–1848. doi: 10.1089/neu.2014.3352

12.

Carroll

, Cassidy

, Cancelliere

, Cote

, Hincapie

, Kristman

, & … Hartvigsen

(2014). Systematic review of the prognosis after mild traumatic brain injury in adults: Cognitive, psychiatric, and mortality outcomes: Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis. Archives of Physical Medicine and Rehabilitation, 95(Suppl 3), S152–173.

13.

Cook

K. F.

, Bombardier

C. H.

, Bamer

A. M.

, Choi

S. W.

, Kroenke

, & Fann

J. R.

(2011). Do somatic and cognitive symptoms of traumatic brain injury confound depression screening?Archives of Physical Medicine and Rehabilitation, 92(5), 818–823.

14.

Corona

, Rastrelli

, Limoncin

, Sforza

, Jannini

E. A.

, & Maggi

(2015). Interplay between premature ejaculation and erectile dysfunction: A systematic review and meta-analysis. J Sex Med, 12(12), 2291–2300. doi: 10.1111/jsm.13041

15.

Davis

C. M.

(1998). Handbook of sexuality-related measures. Thousand Oaks, Calif.: Sage Publications.

16.

Delgadillo

, Payne

, Gilbody

, Godfrey

, Gore

, Jessop

, & Dale

(2012). Brief case finding tools for anxiety disorders: Validation of GAD-7 and GAD-2 in addictions treatment. Drug Alcohol Depend, 125(1-2), 37–42. doi: 10.1016/j.drugalcde2012.03.011

17.

Diaz-Arrastia

, & Kenney

(2015). Epidemiology of traumatic brain injury. Vos Dans

P. E.

& Diaz-Arrastia

(dir.), Traumatic brain injury (1st edition) (pp. 183–191). UK: John Wiley & Sons, Ltd.

18.

Donker

, van Straten

, Marks

, & Cuijpers

(2011). Quick and easy self-rating of Generalized Anxiety Disorder: Validity of the Dutch web-based GAD-7, GAD-2 and GAD-SI. Psychiatry Res, 188(1), 58–64. doi: 10.1016/j.psychres.2011.01.016

19.

Downing

, & Ponsford

(2016). Sexuality in individuals with traumatic brain injury and their partners. Neuropsychol Rehabil1–10. doi: 10.1080/09602011.2016.1236732

20.

Fann

, Bombardier

, Dikmen

, Esselman

P. C.

, Warms

, Pelzer

, & … Temkin

(2005). Validity of the Patient Health Questionnaire-9 in assessing depression following traumatic brain injury. The Journal of Head Trauma Rehabilitation, 20(6), 501–511.

21.

Faul

, & Coronado

(2015). Epidemiology of traumatic brain injury. Grafman

Dans J.

& Salazar

A. M.

(dir.), Handbook of Clinical Neurology (3rd series) (Vol 127, p. 3–13). Amsterdam: Elsevier.

22.

García-Campayo

, Zamorano

, Ruiz

M. A.

, Pardo

, Perez-Paramo

, Lopez-Gomez

, & … Rejas

(2010). Cultural adaptation into Spanish of the generalized anxiety disorder-7 (GAD-7) scale as a screening tool. Health Qual Life Outcomes, 8, 8. doi: 10.1186/1477-7525-8-8

23.

Gouvernement du Québec/Ministère de la Santé et des Services Sociaux, & Société de l’assurance automobile du Québec. (2005). Orientations ministérielles pour le TCCL. Retrieved from http://www.repar.ca/admin/files/images/Orientations_minist%C3%A9rielles_TCCL.pdf

24.

Hanks

R. A.

, Sander

, Millis

S. R.

, Hammond

F. M.

, & Maestas

K. L.

(2013). Changes in sexual functioning from 6 to 12 months following traumatic brain injury: A prospective TBI model system multicenter study. J Head Trauma Rehabil, 28(3), 179–185. doi: 10.1097/HTR.0b013e31828b4fae

25.

Henderson

D. J.

, Boyd

C. J.

, & Whitmarsh

(1995). Women and illicit drugs: Sexuality and crack cocaine. Health Care Women Int, 16(2), 113–124. doi: 10.1080/07399339509516163

26.

Hibbard

M. R.

, Gordon

W. A.

, Flanagan

, Haddad

, & Labinsky

(2000). Sexual dysfunction after traumatic brain injury. NeuroRehabilitation, 15(2), 107–120.

27.

IBM. (2012). IBM SPSS Advanced Statistics 21. IBM Corporation.

28.

Katz

, Cohen

, & Alexander

M. P.

(2015). Mild traumatic brain injury. Grafman

Dans J.

& Salazar

A. M.

(dir.), Handbook of Clinical Neurology (3rd series) (Vol. 127 pp. 131–156). Amsterdam: Elsevier.

29.

King

B. E.

, & Allgeier

E. R.

(2000). The Sexual Desire Inventory as a measure of sexual motivation in college students. Psychological Reports, 86(1), 347–350.

30.

Kramer

T. H.

, Nelson

D. F.

, & Li

P. W.

(1993). AIDS knowledge and risk behaviours among traumatic brain injury survivors with coexisting substance abuse. Brain Inj, 7(3), 209–217.

31.

Kreuter

, Dahllof

A. G.

, Gudjonsson

, Sullivan

, & Siosteen

(1998). Sexual adjustment and its predictors after traumatic brain injury. Brain Inj, 12(5), 349–368.

32.

Lovell

M. R.

, Iverson

G. L.

, Collins

M. W.

, Podell

, Johnston

K. M.

, Pardini

, & … Maroon

J. C.

(2006). Measurement of symptoms following sports-related concussion: Reliability and normative data for the post-concussion scale. Appl Neuropsychol, 13(3), 166–174. doi: 10.1207/s15324826an1303_4

33.

Lowe

, Decker

, Muller

, Brahler

, Schellberg

, Herzog

, & Herzberg

P. Y.

(2008). Validation and standardization of the Generalized Anxiety Disorder Screener (GAD-7) in the general population. Med Care, 46(3), 266–274. doi: 10.1097/MLR.0b013e318160d093

34.

Malary

, Khani

, Pourasghar

, Moosazadeh

, & Hamzehgardeshi

(2015). Biopsychosocial determinants of hypoactive sexual desire in women: A narrative review. Mater Sociomed, 27(6), 383–389. doi: 10.5455/msm.2015.27.383-389

35.

Malec

J. F.

, Machulda

M. M.

, & Smigielski

(1993). Cluster analysis of neuropsychological test results among patients with traumatic brain injury (TBI): Implications for a model of TBI-related disability. The Clinical Neuropsychologist, 7(1), 48–58. doi: 10.1080/13854049308401887

36.

Meagher

A. D.

, Beadles

C. A.

, Doorey

, & Charles

A. G.

(2015). Racial and ethnic disparities in discharge to rehabilitation following traumatic brain injury. J Neurosurg, 122(3), 595–601. doi: 10.3171/2014.10.JNS14187

37.

Moreno

, Arango-Lasprilla

, Gan

, & McKerral

(2013). Sexuality after traumatic brain injury: A critical review. NeuroRehabilitation, 32(1), 69–85. doi: 10.3233/NRE-130824

38.

Moreno

, Gan

, Zasler

, & McKerral

(2015). Experiences, attitudes, and needs related to sexuality and service delivery in individuals with traumatic brain injury. NeuroRehabilitation, 37(1), 99–116. doi: 10.3233/NRE-151243

39.

Moreno

, & McKerral

(2016). Relationships between risky sexual behaviour, dysexecutive problems, and mental health in the years following interdisciplinary TBI rehabilitation. Neuropsychological Rehabilitation, 1–23. doi: 10.1080/09602011.2015.1136222

40.

Moreno

J. A.

, Arango Lasprilla

, & McKerral

(2015). The relationship between postconcussion symptoms and sexual quality of life in individuals with traumatic brain injury. Sex Disabil, 33, 483–498. doi: 10.1007/s11195-015-9414-8

41.

Mounce

L. T. A.

, Williams

W. H.

, Jones

J. M.

, Harris

, Haslam

S. A.

, & Jetten

(2013). Neurogenic and psychogenic acute postconcussion symptoms can be identified after mild traumatic brain injury. The Journal of Head Trauma Rehabilitation, 28(5), 397–405.

42.

O’Carroll

R. E.

, Woodrow

, & Maroun

(1991). Psychosexual and psychosocial sequelae of closed head injury. Brain Inj, 5(3), 303–313.

43.

Ortega

, Zubeidat

, & Sierra

J. C.

(2006). Further examination of measurement properties of Spanish version of the Sexual Desire Inventory with undergraduates and adolescent students. Psychological Reports, 99(1), 147–165.

44.

Osborn

A. J.

, Mathias

J. L.

, & Fairweather-Schmidt

A. K.

(2014). Depression following adult, non-penetrating traumatic brain injury: A meta-analysis examining methodological variables and sample characteristics. Neurosci Biobehav Rev, 47, 1–15. doi: 10.1016/j.neubiorev.2014.07.007

45.

Osborn

A. J.

, Mathias

J. L.

, & Fairweather-Schmidt

A. K.

(2016). Prevalence of anxiety following adult traumatic brain injury: A meta-analysis comparing measures, samples and postinjury intervals. Neuropsychology, 30(2), 247–261. doi: 10.1037/neu0000221

46.

Osborn

A. J.

, Mathias

J. L.

, Fairweather-Schmidt

A. K.

, & Anstey

K. J.

(2016). Anxiety and comorbid depression following traumatic brain injury in a community-based sample of young, middle-aged and older adults. J Affect Disord, 213, 214–221. doi: 10.1016/j.jad.2016.09.045

47.

Pearce

, Cartwright

, Cocks

, & Whitworth

(2016). Inhibitory control and traumatic brain injury: The association between executive control processes and social communication deficits. Brain Inj, 30(13-14), 1708–1717. doi: 10.1080/02699052.2016.1202450

48.

Pedrero-Perez

E. J.

, Ruiz-Sanchez de Leon

J. M.

, Lozoya-Delgado

, Llanero-Luque

, Rojo-Mota

, & Puerta-Garcia

(2011). [Prefrontal symptoms assessment: Psychometric properties and normative data of the Dysexecutive Questionnaire (DEX) in a sample from the Spanish population]. Rev Neurol, 52(7), 394–404.

49.

Ponsford

, Downing

M. G.

, & Stolwyk

(2013). Factors associated with sexuality following traumatic brain injury. J Head Trauma Rehabil, 28(3), 195–201. doi: 10.1097/HTR.0b013e31828b4f7b

50.

Ponsford

, Lee

N. K.

, Wong

, McKay

, Haines

, Alway

, & … O’Donnell

M. L.

(2016). Efficacy of motivational interviewing and cognitive behavioral therapy for anxiety and depression symptoms following traumatic brain injury. Psychol Med, 46(5), 1079–1090. doi: 10.1017/S0033291715002640

51.

Rapkin

B. D.

, & Luke

D. A.

(1993). Cluster analysis in community research: Epistemology and practice. American Journal of Community Psychology, 21(2), 247–277. doi: 10.1007/bf00941623

52.

Ruiz

M. A.

, Zamorano

, Garcia-Campayo

, Pardo

, Freire

, & Rejas

(2011). Validity of the GAD-7 scale as an outcome measure of disability in patients with generalized anxiety disorders in primary care. J Affect Disord, 128(3), 277–286. doi: 10.1016/j.jad.2010.07.010

53.

Sander

, Maestas

K. L.

, Nick

T. G.

, Pappadis

M. R.

, Hammond

F. M.

, Hanks

R. A.

, & Ripley

D. L.

(2013). Predictors of sexual functioning and satisfaction 1 year following traumatic brain injury: A TBI model systems multicenter study. J Head Trauma Rehabil, 28(3), 186–194. doi: 10.1097/HTR.0b013e31828b4f91

54.

Sander

, Maestas

K. L.

, Pappadis

M. R.

, Sherer

, Hammond

F. M.

, Hanks

, & NIDRR Traumatic Brain Injury Model Systems Module Project on Sexuality After TBI. (2012). Sexual functioning 1 year after traumatic brain injury: Findings from a prospective traumatic brain injury model systems collaborative study. Arch Phys Med Rehabil, 93(8), 1331–1337. doi: 10.1016/j.apmr.2012.03.037

55.

Sander

A. M.

, Maestas

K. L.

, Pappadis

M. R.

, Hammond

F. M.

, Hanks

R. A.

, & NIDILRR Traumatic Brain Injury Model Systems Module Project on Sexuality After TBI. (2016). Multicenter study of sexual functioning in spouses/partners of persons with traumatic brain injury. Arch Phys Med Rehabil, 97(5), 753–759. doi: 10.1016/j.apmr.2016.01.009

56.

Saxton

M. E.

, Younan

S. S.

, & Lah

(2013). Social behaviour following severe traumatic brain injury: Contribution of emotion perception deficits. NeuroRehabilitation, 33(2), 263–271. doi: 10.3233/NRE-130954

57.

Shinagawa

, Nakaaki

, Hongo

, Murata

, Sato

, Matsui

, & … Furukawa

(2007). Reliability and validity of the Japanese version of the Dysexecutive Questionnaire (DEX) in Alzheimer’s disease: Validation of a behavioral rating scale to assess dysexecutive symptoms in Japanese patients with Alzheimer’s disease. International Journal of Geriatric Psychiatry, 22(10), 951–956.

58.

Sidik

S. M.

, Arroll

, & Goodyear-Smith

(2012). Validation of the GAD-7 (Malay version) among women attending a primary care clinic in Malaysia. J Prim Health Care, 4(1), A11.

59.

Simblett

, & Bateman

(2011). Dimensions of the Dysexecutive Questionnaire (DEX) examined using Rasch analysis. Neuropsychological Rehabilitation, 21(1), 1–25.

60.

Simpson

(2001). Addressing the sexual concerns of persons with traumatic brain injury in rehabilitation settings: A framework for action. Brain Impairment, 2(2), 97–108.

61.

Spector

I. P.

, Carey

M. P.

, & Steinberg

(1996). The sexual desire inventory: Development, factor structure, and evidence of reliability. J Sex Marital Ther, 22(3), 175–190. doi: 10.1080/00926239608414655

62.

Spitzer

R. L.

, Kroenke

, Williams

J. B.

, & Lowe

(2006). A brief measure for assessing generalized anxiety disorder: The GAD-7. Arch Intern Med, 166(10), 1092–1097. doi: 10.1001/archinte.166.10.1092

63.

Swinson

R. P.

(2006). The GAD-7 scale was accurate for diagnosing generalised anxiety disorder. Evid Based Med, 11(6), 184. doi: 10.1136/ebm.11.6.184

64.

Symonds

, Boolell

, & Quirk

(2007). Development of a questionnaire on sexual quality of life in women. Journal of Sex & Marital Therapy, 31, 385–397.

65.

Tate

, Kennedy

, Ponsford

, Douglas

, Velikonja

, Bayley

, & Stergiou-Kita

(2014). INCOG recommendations for management of cognition following traumatic brain injury, part III: Executive function and self-awareness. The Journal of Head Trauma Rehabilitation, 29(4), 338–352.

66.

Valovich

, & Leach

(2012). Psychometric properties of self-report concussion scales and checklists. Journal of Athletic Training, 47(2), 221–223.

67.

van der Naalt

, & Spikeman

J. M.

(2015). Follow-up and community integration of mild traumatic brain injury. Vos

Dans P. E.

& Diaz-Arrastia

(dir.), Traumatic brain injury (1st edition) (pp. 211–225). UK: John Wiley & Sons, Ltd.

68.

Wild

, Eckl

, Herzog

, Niehoff

, Lechner

, Maatouk

, & … Lowe

(2013). Assessing generalized anxiety disorder in elderly people using the GAD-7 and GAD-2 scales: Results of a validation study. Am J Geriatr Psychiatry, 22(10), 1029–1038. doi: 10.1016/j.jag2013.01.076