The Impact of Motor,Non-Motor,and Social Aspects on the Sexual Health of Men Living with Parkinson’s Disease

INTRODUCTION

Parkinson’s disease (PD) is an idiopathic, neurodegenerative, multisystemic, progressive, and irreversible disorder with a large spectrum of motor and non-motor signs and symptoms [1]. Its incidence increases with age and rises sharply after 65 years [2]. According to the Global Burden of Disease study, PD was the only neurological disorder with increasing age-standardized rates of deaths, prevalence, and disability-adjusted life-years between 1990 and 2015 [3].

According to the World Health Organization, sexual health (SH) is “a state of physical, emotional, mental and social well-being in relation to sexuality” [4]. SH involves many factors, including organic causes, environmental influences, and psychological factors. It is a complex phenomenon, making its study and understanding challenging [5].

Among the non-motor functions affected by PD, sexual dysfunction (SD) has a negative impact on SH [6, 7], and can significantly reduce the quality of life for patients and their sex partners [8]. Unfortunately, SD is often underreported and receives little attention from health professionals [9, 10]. Studies have shown that SD is more prevalent in people with PD (PwPD) than in healthy individuals [11–13], and may be an early symptom of PD [14]. The prevalence ranges between 42% and 79% in men with PD (MwPD) and between 36 and 87% in women with PD (WwPD) [6, 15–17]. More than 50% of PwPD reported that their sex activity was affected by the disease [18] and decreased progressively over a two-year follow-up period [19].

Regarding age, studies show different results: some show that SD is worse in older PwPD [13, 20–23] while others show that younger people report more SD [24] or that SD is age-independent [22].

Regarding disease progression and disease severity, some studies showed that SD increases with disease progression [18, 26] and disease severity [15, 26–28], while others showed no correlation between disease progression [20, 30] or disease severity [16, 31]. In MwPD, disease severity was associated with libido loss [15].

Frequency of intercourse, sexual arousal, subjective abnormal sexual fantasies, or sexual satisfaction deteriorated in both genders, but especially in MwPD [23]. The main SD observed in MwPD were 1) hypoactive sexual desire disorder, reported by 83% of participants [17]; 2) erectile dysfunction (ED), reported between 42.6% and 79% of MwPD [6, 33]; 3) difficulty reaching orgasm, reported by 39.5% [6], premature ejaculation, reported between 40.6% and 79% of MwPD [6, 34]; 5) anejaculation, reported by 87% [17], and 6) hypersexuality, reported by 5.2% of MwPD [35].

Several alterations in sensory, motor, mental, and autonomic functions associated with PD and social aspects can directly or indirectly affect the SH [19, 36].

Regarding motor alterations associated with PD, rigidity, tremor, postural instability, immobility in bed, incoordination in fine movements of the hands, and facial hypomimia can make it difficult for patients to experience pleasure and sexual arousal, as well as be a barrier to full participation in sexual activity [6, 34]. In fact, PwPD who reported SD showed higher motor symptom severity than those without SD [18]. In MwPD, motor symptom severity was associated with ED [20] and decreased quality of SH of the sex partner [7]. Increased motor disability level in MwPD is associated with decreased SH [9, 34] and sexual satisfaction [37].

Among the non-motor alterations, depression and anxiety have been identified as the factors most correlated with SD [13, 37]. Depression is a predictor for libido loss and decreased sexual desire in PwPD [15]. For MwPD, lower depression is associated with higher sexual activity [19]. Few studies that have investigated the impact of cognitive changes on the SH of PwPD showed no correlation between cognitive status and SD [19, 24]. Particularly in MwPD, it was found an association between cognitive decline and libido loss [15]. Urinary, autonomic dysfunction, and fatigue have also been associated with SD complaints, such as loss of libido and decreased sexual satisfaction in PwPD [13, 15].

Among the social factors, the quality of the marital relationship has been bidirectionally related to SH [38]. Brown et al. (1990) showed that couples where one of the partners had PD who reported a better marital relationship were more satisfied with their sex life and vice versa [9]. However, satisfaction with the marital relationship varied between genders: dissatisfaction with the marital relationship and the sex life of both partners was more significant when the PwPD was a man. MwPD rejected sex less often and reported higher desire and more dissatisfaction with their sex life than women [6, 7].

SH is a multifaceted issue that can be attributed to not only organic causes, but also environmental and psychological factors. SD is a prevalent and disturbing non-motor symptom of PD, mainly for men. Although several studies have investigated SD in PD, there is a lack of complete and consistent data on SH in MwPD. This study aimed to investigate the impact of motor, non-motor, and social factors on SH of MwPD who reported having an active sex life.

MATERIALS AND METHODS

Study procedures

The study flow is shown in Fig. 1.

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Fig. 1

The schematic study designs.

After agreeing to take part in the study, participants were requested to specify their preferred day and time for the remote interview, considering the on-period of dopaminergic medication (40–120 min post the last intake). Then, the researchers applied the questionnaire, which included general information, information associated with PD, and the structured instruments selected for the study.

The interviews for this study were conducted by the same interviewer in two separate sessions, with a gap of less than 7 days between them. Each interview lasted around 30–35 min.

RESULTS

The participants’ demographic and clinical characteristics are shown in Table 1.

Out of all the participants, it was found that 31% were in Stage 1, 51% were in Stage 2, and 18% were in Stage 3, according to the H&Y classification [53]. Additionally, 68% of participants were less than 60 years old, and 64% presented EOPD. There was no statistically significant difference for IIEF and SQ-M scores between participants with EOPD and LOPD.

It is important to note that although 10 of the participants reported mild to moderate DDS according to item 1.6 of the MDS-UPDRS I (6 involving compulsion for shopping, 3 for games and 1 for candies), none of them reported hypersexuality.

DISCUSSION

SH is essential for maintaining overall well-being and health. Decreased SH has consequences that extend beyond the individual and can affect families and society [54]. However, there has been a lack of research on SH in people with PD. To the best of our knowledge, the present study was the first aiming to investigate the impact of the motor, non-motor, and social aspects on the short and long-term SH in MwPD by different but complementary instruments developed to assess SH.

Our results showed that despite several motor, non-motor, and social factors had a significant role in determining SH, only motor disability level in daily living was a predictor for short-term SH and EF, while depression severity was the unique predictor for long-term SH. Interestingly, we did not find any significant association between SH and factors such as age, disease onset, DDL, DDAL and DDS. These findings suggest that addressing motor disability and mental health may be crucial in improving the overall health of MwPD.

Taken together, several considerations can be made based on the results.

In the present study, we utilized two different instruments to evaluate SH in MwPD. The first tool, IIEF, assessed overall SH and specifically evaluated EF over the past four weeks. The second tool, SQ-M, based on a qualitative approach, evaluated SH over the past six months. We found that both IIEF and SQ-M were strongly correlated with each other and with the same variables, such as disease progression, disease duration, global cognitive capacity, depression, self-esteem, motor and non-motor disability in daily living, fatigue, and sleep. However, only SQ-M was correlated with the CRQ. Most importantly, different factors predicted IIEF and SQ-M scores. While previous studies have primarily used IIEF to evaluate SH in MwPD, our findings suggest that incorporating the SQ-M questionnaire can offer additional insights into how PD affects SH.

Based on our results, many MwPDs experience ED. Specifically, our findings show that 47% of MwPD reported ED based on IIEF, with 17% experiencing moderate to severe ED. Although age did not predict SH in the present study, it is important to note that 28% of participants under the age of 60 reported ED. Of these, 13% reported moderate to severe dysfunction. These findings are in line with previous studies that have identified ED as the most prevalent SD among MwPD, with prevalence rates ranging from 42.6% to 79% [6, 33].

Our results have demonstrated the importance of recognizing ED as a non-motor symptom in MwPD. We found that while several factors were associated with EF, it was only the motor disability in daily living that was able to predict the presence of ED and short-term SH. Previous research has also shown that individuals with PD who have more severe motor symptoms and disability tend to experience more SD [9, 37] and ED [20], which is consistent with our findings. Although the MDS-UPDRS Part II assesses various factors that may affect sexual performance, such as bed mobility, dressing ability, and hand coordination, it is not entirely clear how motor disability specifically impacts EF. Our findings emphasize the need for clinicians to consider the impact of motor disability on sexual health in individuals with PD and highlight the demand for more studies to understand the relationship between motor disability and EF.

Our findings showed that the severity of depression plays a critical role in predicting long-term SH. This is consistent with previous research emphasizing the close link between depression and sexual dysfunction. In fact, studies conducted by Kotková and Weiss (2013) [37], Vela-Desojo et al. (2020) [13], Raciti et al. (2020) [18], Özcan et al. (2015) [20], and Jitkritsadakul et al. (2015) [34] have also reported similar results. Additionally, our study identified depression severity as a significant predictor of SD in MwPD, which is consistent with the findings of Ferrucci et al. (2016) [33], Kotková and Weiss (2013) [37], and Kummer et al. (2009) [15] that showed depression as a predictor for SD in men and women with PD. Specifically, for MwPD, higher levels of depression symptoms were associated with decreased sexual activity, as reported by Picillo et al. (2019) [19]. Since depression is a common non-motor symptom that may even be present before a diagnosis is possible, interventions to prevent or reduce depression are crucial to avoid or minimize the decreased SH in MwPD.

Interestingly, it was found that the total score of SQ-M was significantly correlated only to the quality of marital relationships. This suggests that general aspects of long-term SH are influenced by the complex aspects of marital relationship assessment by DAS. Previous studies have shown that the quality of the marital relationship is closely related to SH in both directions [9, 55]. Our findings reinforce the importance of providing care not only for the patient but also for their partner.

Some previous studies have found associations between other non-motor symptoms and SD [56]. However, the MDS-UPDRS I, PDSS, and FSS, which assess general non-motor symptoms, sleep quality, and fatigue, respectively, although correlated with IIEF and SQ-M scores, had no predictive value for both in the present study. The same was observed for self-esteem: despite some features like drooling, excessive sweating, seborrhea, and hypomimia may decrease self-esteem [11], the RSES scores, although correlated with IIEF and SQ-M scores, had no predictive value for both.

Finally, although dopaminergic medication has been correlated with SD in MwPD [11], the DDL, DDAL, and DDS were not associated with SH in the present study.

The present study presents some strengths: using multidimensional generic instruments to assess SH, quality of couple relationships, depression, and cognition. Moreover, the use of disease-specific instruments that comprehensively assess motor and non-motor dysfunction in PD. The results obtained are promising and can serve as a foundation for further research in the field.

Our study has some limitations to be considered. One of the main limitations is that it was designed as cross-sectional, meaning that the information gathered was only based on data from a specific point in time. However, we tried to minimize this limitation by using different tools to assess the STSH and LTSH. Another limitation is that the sample size may not allow for large generalization to the PD population. However, we included participants from 5 different geographical areas with sizable sociocultural differences, which may have helped to minimize this limitation. Lastly, and importantly, we did not find men of advanced age and stage of PD who reported having an active sex life to be included in this study. This can be considered a study limitation. Further studies are needed to investigate SH in MwPD who are no longer sexually active.

In conclusion, various motor, non-motor, and social factors were found to be associated with SH in MwPD, regardless of their age, disease onset, and medication dosage. However, motor disability in daily living was the only factor that could predict short-term SH and ED, while the severity of depression was found to predict long-term SH. Therefore, to prevent the decline in SH, an interdisciplinary approach that addresses these factors should be made available to people with PD from the early stages of the disease.