Caregiver Experiences Across Three Neurodegenerative Diseases: Alzheimer’s,Parkinson’s,and Parkinson’s With Dementia

Abstract

Objective: This article asks whether distinct caregiver experiences of Alzheimer’s disease (AD), Parkinson’s disease (PD), and Parkinson’s disease with dementia (PDD) spouses are accounted for by disease diagnosis or by a unique combination of symptoms, demands, support, and quality of life (QOL) cross disease groups. Method: One hundred five live-in spouse caregivers (71.4 ± 7 years) were surveyed for persons with AD (39%), PD (41%), and PDD (20%). A hierarchical cluster analysis organized caregivers across disease diagnosis into clusters with similar symptom presentation, care demands, support, and QoL. Results: Four clusters cut across disease diagnosis. “Succeeding” cared for mild symptoms and had emotional support. “Coping” managed moderate stressors and utilized formal supports. “Getting by with support” and “Struggling” had the greatest stressors; available emotional support influenced whether burden/depression was moderate or severe. The results remain the same when diagnostic category is added to the cluster analysis. Discussion: This study supports going beyond disease diagnosis when examining caregiver experiences.

Keywords

dementia caregiving quality of life burden expressive support neurodegenerative disease

Introduction

The informal care system of family caregivers is a cornerstone of support and care for persons with neurodegenerative disease living in the community. A relationship exists between care experiences, such as health, duration of care and available resources, and the caregiver’s quality of life (QoL; Goldsworthy & Knowles, 2008). To better understand how these characteristics, care demands, and supports cluster together in the care experience, we need to study a range of neurodegenerative diseases whose experiences may overlap. For example, presenting symptoms may be shared between Alzheimer’s disease (AD), Parkinson’s disease (PD), and its associated dementia (PDD), and lead to similar care demands. Comparing experiences and moderating factors across neurodegenerative caregiver groups may be a richer source of information than examining the influence of disease-specific stressors based solely on diagnosis. However, comparative studies of caregiver experiences across AD, PD, and PDD are currently limited. Such a comparison among spouse caregivers is the focus of this investigation.

In North America, spouses are often the first in line to assume caregiving responsibilities (Brodaty & Donkin, 2009; Conde-Sala, Garre-Olmo, Turró-Garriga, Vilalta-Franch, & López-Pousa, 2010b; Pinquart & Sörensen, 2011). Caregivers to persons with neurodegeneration may be more burdened and depressed compared with other older adults, and spouses more so due to the increased amount of care related to shared household and relational closeness combined with the absence of alternate roles that buffer against stress (Clipp & George, 1993; Pinquart & Sörensen, 2003, 2011; Raschick & Ingersoll-Dayton, 2004). Although some research has found that spouses experience less burden and more satisfaction than other caregiving relational groups (Bookwala & Schulz, 2000; Chappell, Dujela, & Smith, 2014; Ott, Sanders, & Kelber, 2007; Williams, 2011), most studies agree spouses experience the greatest burden (Conde-Sala, Garre-Olmo, Turró-Garriga, Vilalta-Franch, & López-Pousa, 2010a; Kim, Chang, Rose, & Kim, 2012; Pinquart & Sörensen, 2011; Raschick & Ingersoll-Dayton, 2004). The QoL experience of spouses caring for a person with AD, PD, or PDD will be explored here. Understanding spousal caregiver experiences across disease groups has clinical and community relevance to support services that may improve QoL.

Disease Presentation

Providing care for a spouse with a neurodegenerative disease has a fourfold negative influence on mood compared with age-matched noncaregivers, mainly attributed to the impact of the disease on social isolation, physical health, and sleep (Richardson, Lee, Berg-Weger, & Grossberg, 2013). AD and PD are the two most common neurodegenerative diseases. AD is the most common type of dementia and accounts for 60% to 80% of all dementia diagnosis cases. AD presents mainly as cognitive impairment, with short-term memory difficulties (e.g., learning deficit, amnesia), sensory processing, and language impairment cited as the most common clinical presentations (Erder et al., 2012). PD, on the other hand, is considered primarily a movement disorder with a clinical presentation of tremor, rigidity, slowness of movement, and postural instability. While PD is defined by its motor features, nonmotor symptoms and cognition can also deteriorate. In comparison with changes to short-term memory, recognition, and language in AD, cognitive decline in PD presents mainly as executive dysfunction, fluctuations in attention, visuospatial deficits, and slow/difficulty with retrieval and word-finding (Kurtz & Kaufer, 2011; Watson & Leverenz, 2010). The decline in visuospatial and language retrieval are more rapid in PDD compared with AD (Svenningsson, Westman, Ballard, & Aarsland, 2012).

Changes to cognitive abilities occur in 30% to 80% of persons with PD and can range from mild to severe (Aarsland et al., 2007; Meireles & Massano, 2012; Svenningsson et al., 2012). It is estimated that one third of persons with PD develop cognitive impairment severe enough to be diagnosed as PDD over the course of the disease, which is three to six times greater than the general population (Aarsland et al., 2007; Meireles & Massano, 2012; Svenningsson et al., 2012). Despite its prevalence in PD, cognitive symptoms have only received attention in recent decades and continue to be underdiagnosed (Kudlicka, Clare, & Hindle, 2014). PDD cases are expected to rise because people with PD live longer, increasing the likelihood of developing dementia (Anderson, 2004).

Neurodegenerative Caregiving Experiences

Caregivers of persons with neurodegenerative disease face unique challenges because of the cognitive and physical disabilities specific to their care experience and the need to adapt to continuously changing and demanding situations (Zhu et al., 2015). There are very few comparative studies of spouse caregiver experiences across AD, PD, and PDD (Roland & Chappell, 2015). According to Davis and colleagues, PD caregivers were more likely than AD caregivers to describe tensions and care decision conflicts within the care relationship, leading to stress, disagreement, and relational loss (Davis, Gilliss, Deshefy-Longhi, Chestnutt, & Molloy, 2011). However, in a study with caregivers of persons with AD and PD with similar disease duration and neuropsychiatric inventory score, Cupidi et al. (2012) report that AD caregivers reported lower QoL than PD due to poorer sleep associated with nocturnal wandering. Other comparative studies between these groups exist but do not take relationship status into consideration. These studies reported that PDD caregivers care for more activities of daily living (ADL) dependence, falls, depression, and psychiatric problems compared with AD and PD (Giovannetti et al., 2012; Shin, Youn, Kim, Lee, & Cho, 2012), resulting in greater feelings of burden for the PDD caregiver. Furthermore, memory, apathy, psychosis and depression contributed to caregiver burden in PDD, while cognitive impairment and basic ADL ability contributed to caregiver burden in AD (Shin, Youn, et al., 2012). Shin, Youn and colleagues (2012) speculate that the worse QoL and greater burden in PDD is due to the combination of motor and neuropsychiatric symptoms which may result in more serious functional deficits and dependence compared with AD and PD, but that remains to be empirically tested.

In examining the caregiver burden literature, cognitive inefficiencies, problem behaviors (Cupidi et al., 2012; Gómez-Gallego, Gómez-Amor, & Gómez-García, 2012), time spent on instrumental activities of daily living (IADL; Conde-Sala et al., 2010a; Kim et al., 2012), and care recipient depression (Ornstein et al., 2012; Rowe, McCrae, Campbell, Pe Benito, & Cheng, 2008) are cited as the most relevant sources of AD caregiver burden. In PD, caregiver burden increases with greater motor disability, falls, mood (depression, apathy) and psychiatric complications, as well as with caregiver’s own depression and satisfaction with marital relationship (Aarsland, Larsen, Karlsen, Lim, & Tandberg, 1999; Carter, Stewart, Lyons, & Archbold, 2008; Schrag, Hovris, Morley, Quinn, & Jahanshahi, 2006; Shin, Lee, Youn, Kim, & Cho, 2012). However, cognitive impairment in persons with PD/PDD is still poorly understood as related to caregiver QoL and may be a more important contributor to negative caregiver experiences than the literature suggests (Aarsland et al., 1999; Watson & Leverenz, 2010). Even in the early stages of cognitive impairment (e.g., mild cognitive impairment), these PD caregivers already experience elevated distress compared with those with PD-normal cognition (Szeto et al., 2016). PDD caregivers care for debilitating cognitive decline in the presence of progressing motor, autonomic, sleep, and neuropsychiatric symptoms (Aarsland et al., 2007); therefore, a crucial question is how PDD caregiver QoL experiences compare with AD caregivers, who manage primarily cognitive and behavioral stressors, and PD caregiver, who manage greater mood and functional declines.

Theoretical Model

The Stress Process Model is a conceptual framework focused on the relationship between care experiences and the stress process (Pearlin, Mullan, Semple, & Skaff, 1990). Goldsworthy and Knowles (2008) extended the Stress Process theoretical framework for use with PD caregivers. In their model, caregiving experiences of burden, depression and/or life satisfaction are influenced by the interaction of caregiving background, stressors and supports (Austrom et al., 2014). According to this model, caregiver QoL experiences are influenced directly by health and sociodemographic characteristics, diagnosis, symptom presentation, and resulting care demands. QoL experiences are indirectly influenced by support (Figure 1). This model informed the selection of the study variables. Support can directly moderate burden in caregivers, as well as indirectly provide a buffer from the negative effects of stressors. The use of formal, informal, and/or emotional support influences quality of care and the ability of spouses to cope with care demands (Goldsworthy & Knowles, 2008), which leads to varying QoL experiences.

Figure 1.

The modified stress process model framework.

The aims of this study are to (a) compare QoL experiences of AD, PD, and PDD spouse caregivers, and to (b) cluster caregivers given their unique caregiving stressors, characteristics, and outcomes that contribute to QoL experiences. This adds to our understanding of the care experience across neurodegenerative disease groups. We hypothesize as follows:

Hypothesis 1: Spouse caregiver QoL experiences will be more negatively affected in PDD due to the combined motor and cognitive symptomatology that characterize the diagnosis.

Hypothesis 2: Among all caregivers, there are distinct subgroups given stressors, characteristics, and outcomes that cross disease diagnoses.

This analysis will add to current knowledge on the unique care experiences across dementia caregiving and further our understanding of PDD care. The goal is to inform health care professionals and community programs in assisting spouse caregivers to reduce their stress burden.

Method

Research Design

This article draws on hierarchical cluster analysis to better understand caregiver QoL profiles. A cluster analysis was performed on caregivers without taking disease diagnosis into consideration to explore whether it was meaningful to organize caregivers into subgroups (i.e., caregiver “types”) based on similar stressors, support, and QoL. Caregivers were English-speaking live-in spouses who provided at least 3 hr of care over 3 days per week for the past year to persons living in the community. This study restricts its sample to spouses to control the influence of relationship on caregiving experience; thus, “caregivers” in this study refer to “spouse caregivers.” No caregivers had paid employment outside the home. All care recipients had a physician diagnosis of AD, PD, and/or PDD as reported by the caregiver and different sources were used to identify the AD and PD/PDD samples used. The Ethics Committee at the University of Victoria approved the study and all participants provided informed consent.

Caregivers to individuals with PD and PDD were recruited through local health services, nonprofit organizations, and the voluntary sector between February 2014 and May 2015 from participants living in the province of British Columbia, Canada. Community flyers and advertisements were posted, and 93 interested participants contacted a member of the research team to express their interest. The researcher explained the study and requested their voluntary participation. Following agreement, a time was scheduled for the researcher to administer the interview (over the telephone) or the questionnaire was mailed to the interested participant at the home address; a stamped addressed return envelope was included. Sixty-four questionnaires were completed and included in the analysis: Three of these were administered over the phone (n = 2 PD, n = 1 PDD) and 61 distributed via mail (n = 41 PD, n = 20 PDD). Twenty-nine questionnaires were mailed out and not returned. The three interviews over the telephone took on average 91.3 min to complete. Characteristics of age, gender, self-rated health, age of onset, disease duration were compared between telephone and postal respondents using descriptive statistics; groups were similar (p > .05). Participants were not compensated for their involvement in the study.

A large provincial program of research, the Alzheimer’s Disease Therapy Initiative (ADTI), provided the AD sample for this study. Caregivers of persons diagnosed with dementia who were taking cholinesterase inhibitors (ChEI) covered by the British Columbia Pharmacare were recruited. Interested participants received a phone call 6 months after the initiation of ChEI therapy and arrangements were made for in-person interviews. Data similar to that collected in the PD and PDD samples included support and service use, aspects of caring, health, ADL abilities, behavioral issues, and sociodemographic characteristics. Of the total sample of 906 caregivers, 613 were spouses, of which 300 were caring for someone with AD and a further 158 of those with AD were living in the community (rather than residential care facilities). A sample of 41 of the 158 was randomly chosen. They were statistically similar in age, gender, self-rated health, age of onset and disease duration when compared with the PD/PDD sample (p > .05). The total sample of 105 in this analysis included 41 AD, 43 PD, and 21 PDD caregivers.

Caregiver Measures

Caregivers reported age, gender, and self-rated health. To assess care demand, caregivers reported the number of hours per week spent caring for the care recipient. To assess informal support, caregivers reported whether they received help from family members and or friends, without pay (Yes/No).

Whether caregivers received emotional support from family and/or friends was assessed using the eight-item Expressive Support Scale (ESS; Pearlin et al., 1990; Cronbach’s α = .87). Participants indicated how strongly they agreed from 1 (strongly disagree) to 4 (strongly agree) on statements about friends and family (other than their spouse) such as “have people in your life who make you feel good about yourself” and “at least one friend you can really confide in.”

Caregivers’ QoL experience was measured as life satisfaction, burden, and depression. Definitions of QoL vary; however, it is broadly conceptualized to include both positive and negative aspects of health, spirituality, activity, social support, resources, satisfaction with life situations, affect, cognition, and mood. Life satisfaction was quantified using The Life Satisfaction Scale (LSS), a measure of an individual’s subjective judgment of their own well-being (Cronbach’s = .79; Andrews & Withey, 1976). Participants were asked to rate how they feel about various life domains including health, finances, relationships, housing, transportation, recreation, activities, religion, and self-esteem on a scale of 1 (terrible) to 7 (delightful), with 4 (mixed) being neutral (Andrews & Withey, 1976).

Burden was measured with the Short Zarit Burden Interview (ZBI, 12 items); each item was scored on a scale from 0 (never) to 4 (nearly always), with 2 (sometimes) being neutral (Cronbach’s α = .93; Hébert, Bravo, & Préville, 2000). The instrument includes items on personal strain (n = 3; for example, “Do you feel that your health has suffered because you are caring for your relative?”) and role strain (n = 9; for example, “Do you feel stressed between caring for your relative and trying to meet other responsibilities—work/family?”).

Different measures of depression were available in the two data sets. PD and PDD caregivers were rated using the Centre for Epidemiologic Studies Depression Scale (CESD; Cronbach’s α = .92; Eaton, Muntaner, Smith, Tien, & Ganguli, 2004). Twenty items are included in the CESD scale: for example, being bothered, having a poor appetite, signs of depression, staying focused, feeling fearful, sleep quality, and loneliness. The CESD scores the frequency of how the participant might have felt or behaved in the past week on a scale from 0 (rarely or none, less than 1 day) to 3 (most of all of the time, 5-7 days). AD caregivers were rated using the depression scale in the Hospital Anxiety and Depression (HAD) scale (Cronbach’s α = .83; Zigmond & Snaith, 1983). The HAD consists of a seven-item depression scale that focuses on subjective and emotional aspects of the participants’ mood. Items are rated on frequency felt in the past week from 0 (occasionally/hardly) to 4 (often/very much). In this analysis, PD caregivers were rated at risk of clinical depression (Yes/No) if they scored 16 or greater on the CESD (Radloff, 1977), and AD caregivers were rated at risk of clinical depression (Yes/No) if they scored 8 or greater on the HAD (Zigmond & Snaith, 1983).

Care Recipient Measures

Caregivers reported on age, gender, age of disease onset, most recent primary diagnosis, and ChEI medication prescribed (Aricept®, Reminyl®, Exelon®) for the care recipient. Patient resource use was defined as the number of formal services used to assist with care chosen from a list of 18 items and an option for “other”; for example, adult day care, respite, therapies, meal services, bathing, counseling, and legal resources.

Caregivers reported care recipients’ cognition, ADL ability, and behavior. Cognitive impairment was measured by having caregivers rate the stage of memory loss/dementia as early/mild, middle/moderate, or late/severe.

Caregivers reported whether the care recipient needed no help (0) or partial/total help (1) on six items of basic ADL abilities (Katz & Akpom, 1976; bathing, dressing, toileting, transferring, continence, and feeding; when summed, Cronbach’s α = .91) and on a scale of 1 to 4 whether no (1), some (2-3) or total (4) help was needed on eight items of instrumental ADL abilities (Lawton & Brody, 1969; telephone, shopping, food preparation, housekeeping, laundry, transportation, medication, finances; when summed, Cronbach’s α = .89).

Caregivers reported presence of three behavior problems dealt with (a) verbally agitated behaviors, such as complaining, yelling, swearing, or arguing; (b) nonaggressive physical behaviors, such as wandering (day or night), repetitive mannerisms; and (c) physically aggressive behaviors, such as hitting, grabbing, or spitting that are dangerous to self or others (yes/no to each).

Analysis

Descriptive statistics relied on one-way ANOVA (Tukey–Kramer post hoc for unequal group sizes) for continuous variables and Cross Tabs chi-square tests for categorical variables to compare between disease groups (AD, PD, PDD). A cluster analysis on all participants examined whether it was meaningful to organize caregivers into subgroups (i.e., caregiver “types”) with similar stressors, support, and QoL. The variables used in the cluster analysis were the stressors and supports that were significantly correlated to one of the measures of QoL experience—burden, depression, life satisfaction—at the bivariate level in the entire sample. Correlations were conducted using Pearson (continuous) and Spearman Rank (categorical) coefficients. The variables used in the cluster analysis included caregiver measures of care hours, expressive support, burden, depression and life satisfaction; as well as care recipient measures of cognitive impairment, IADL assistance, and presence of problem behaviors. The cluster analysis was then rerun including disease diagnosis as a variable and the results compared.

Hierarchical cluster analysis using Ward’s method, and squared Euclidean distances, determined the optimal number of clusters. The cluster analysis was then rerun using k-means clustering with the selected number of clusters obtained from Ward’s method to allocate every case in the sample to only one cluster. One-way ANOVA with Tukey post hoc (continuous) and chi-square (categorical) with the dependent variable of cluster membership were run, provided means for each cluster on each variable and the magnitude of how well the variables discriminate between clusters (i.e., F-values). Statistical significance was set at .05. A sample size of 2^m, where m equals the number of clustering variables was used to ensure sufficient power (Formann, 1984).

Results

Sample Characteristics Across Disease Groups

One hundred five spouse caregivers were included in the sample (Table 1). Caregivers were on average 71.4 years of age and caring for 7.1 years; 74.3% were female. Age, gender, self-rated health, care recipient age, and disease duration were similar across disease group (p > .05, Table 1). As expected, persons with AD (56% mild, 34% moderate, 10% severe) had a similar level of cognitive impairment compared with persons with PDD (43% mild, 43% moderate, 14% severe; p > .05); both AD and PDD had more severe cognitive impairment than persons with PD (54% none, 33% mild, 14% moderate; p = .00). Persons with PD had the greatest impairment in ADL ability (4.58 ± 1.8), followed by persons with PDD (2.95 ± 2.4) and finally persons with AD (0.81 ± 1.5; p < .03). Persons with PDD had the greatest impairment in IADL ability (21.81 ± 2.7), followed by persons with AD (18.22 ± 4.75), and finally persons with PD (14.74 ± 4.6; p < .003). Half of caregivers in the entire sample (53.3%) reported at least one problem behavior. Interestingly, persons with PDD had more verbal, physical, and aggressive problem behaviors (76%) than AD (34.1%, p < .02) and were more physically aggressive (33.3%) than PD (9.3%, p = .01).

Table 1.

Descriptive Characteristics of the Sample (One-Way ANOVA, Chi-Square).

	All	AD	PD	PDD	Significance (p<)
Number (F)	105 (78)	41 (30)	43 (32)	21 (16)
^aCaregiver age (years)	71.43 ± 7.4	71.76 ± 6.4	69.97 ± 8.3	73.76 ± 7.4	.21
Self-rated health	2.04 ± 0.8	2.17 ± 0.7	1.93 ± 0.8	2.05 ± 0.7	.34
Care recipient age (years)	74.14 ± 6.9	73.71 ± 6.7	73.02 ± 7.9	77.29 ± 5.1	.12
Care recipient age at onset (years)	66.30 ± 9.5	63.51 ± 7.8	63.07 ± 10.5	65.71 ± 7.6	.11
Disease duration (years)	7.11 ± 6.5	8.06 ± 2.9	8.52 ± 6.6	11.84 ± 7.2	.09
^bAricept (%)	34.3	68.3^c,d	4.7	28.6	.001
Exelon (%)	13.3	17.0	9.5	23.8	.20
Reminyl (%)	15.2	29.2^c,d	0.0	9.5	.05
Cognitive impairment					.00
None (n/%)	23/21.9	0^c	23/53.5^d	0	.00
Mild (n/%)	46/43.8	23/56.1^c	14/32.6^d	9/42.9	.00
Moderate (n/%)	29/27.6	14/34.1^c	6/13.9^d	9/42.9	.00
Severe (n/%)	7/6.6	4/9.8^c	0^d	3/14.2	.00
ADL	3.75 ± 2.5	0.81 ± 1.5^c,d	4.58 ± 1.8^d	2.95 ± 2.4	.003
IADL	17.61 ± 5.0	18.22 ± 4.75^c,d	14.74 ± 4.6^d	21.81 ± 2.7	.008
^bVerbally agitating behavior (%)	36.2	22.0^d	39.5	57.1	.02
Physically nonaggressive behavior (%)	34.3	19.5^c,d	39.5	52.4	.01
Physically aggressive behavior (%)	12.4	4.9^d	9.3^d	33.3	.01
Caregiving hours	2.94 ± 2.09	3.05 ± 2.2	2.62 ± 1.67	3.42 ± 2.65	.35
Informal support (%)	51.4	46.3	46.5	71.4	.21
Formal support	3.24 ± 2.2	1.19 ± 1.6^c	2.40 ± 2.2^d	3.91 ± 2.4	.02
Expressive support	20.61 ± 8.1	13.22 ± 4.9^c	26.21 ± 5.2	23.95 ± 6.6	.01
Burden	13.4 ± 10.8	11.39 ± 11.8^d	12.37 ± 10.5^d	18.81 ± 8.1	.03
Depression (%)	21.9	14.6^d	16.3^d	47.7	.001
Life satisfaction	4.15 ± 1.6	4.39 ± 2.0^d	4.40 ± 1.2^d	3.19 ± 1.1	.02

M ± SD.

Percentage of the total number in disease group; AD = Alzheimer’s disease; PD = Parkinson’s disease; PDD = Parkinson’s disease dementia; F = female; ADL = basic activities of daily living; IADL = instrumental activities of daily living.

Significantly different from PD.

Significantly different from PDD.

Care hours and percentage of caregivers who received informal support from family and/or friends were similar across disease groups (Table 1). It was unexpected that care demands (care hours) would be similar, since stressors varied across groups. The entire sample of care recipients used on average three formal support services. PDD care recipients used the greatest number of formal support services (3.91 ± 2.4, p < .02), followed by PD (2.40 ± 2.2), and finally AD (1.19 ± 1.6). PD caregivers reported similar feelings of emotional support (26.21 ± 5.2) from family and/or friends as PDD caregivers (23.95 ± 6.6) and greater emotional support compared with AD caregivers (13.22 ± 4.9, p < .001). In the entire sample, caregivers were mildly satisfied with life (LSS = 4.15 ± 1.6), moderately burdened (ZBI = 13.4 ± 10.8), and 22% were considered depressed but PDD caregivers emerge as significantly more burdened (p < .003), depressed (p < .001) and experienced decreased life satisfaction (p < .02) compared with both PD and AD caregivers.

Cluster Analysis

Hierarchical cluster analysis conducted without disease group as a variable, revealed four types of caregiver experiences, supporting the notion of going beyond disease diagnosis when examining caregiver needs and experiences (Table 2). The negative outcomes of burden and depression varied; however, life satisfaction, a positive outcome of the caregiver experience, was similar across all four clusters (p = .10). This supports negative and positive outcomes as distinct caregiving constructs that are independently influenced. The clusters are presented from most positive (i.e., least burdened and depressed) to most negative (i.e., most burdened and/or depressed) experience: succeeding, coping, getting by with support and struggling (Figure 2).

Table 2.

Descriptive Characteristics of the Clusters (One-Way ANOVA, Chi-Square).

	Succeeding	Coping	Getting by with support	Struggling	Significance (p<)
Number	25	32	32	16
^aCaregiver age (years)	71.7 ± 7.5	71.8 ± 6.2	71.8 ± 8.3	69.6 ± 8.0	.78
Self-rated health	1.7 ± 0.6	2.1 ± 0.7	2.2 ± 0.8	2.2 ± 0.8	.06
Care recipient age (years)	71.6 ± 8.4^b	73.8 ± 6.4	76.8 ± 6.2	73.4 ± 6.1	.04
Care recipient age at onset (years)	63.9 ± 10.9	69.4 ± 9.4	64.7 ± 8.0	66.9 ± 9.2	.11
Disease duration (years)	6.2 ± 6.1^b	4.5 ± 5.9	10.9 ± 5.9^c	6.3 ± 6.4	.00
^dAricept (n)	0^c	23^e	7^c	6	.00
Exelon (n)	1	4	7	7	.18
Reminyl (n)	1	7	3	3	.19
Diagnosis					.00
AD (n)	1^c,e	28	2^c,e	10	.00
PD (n)	24^b,c,e	2	14^c,e	3	.00
PDD (n)	0^b	2	16^c,e	3	.00
Cognitive impairment					.00
None (n)	17^b,c,e	0	3	3	.00
Mild (n)	6^b,c	19	15	6	.00
Moderate (n)	1^b,c,e	12	10	6	.00
Severe (n)	1^b	1	4	1	.00
ADL	5.7 ± 2.0^c,e	1.8 ± 1.5^e	4.4 ± 2.2^c	3.5 ± 2.5	.00
IADL	13.2 ± 4.6^b,c,e	17.4 ± 4.9	20.3 ± 3.5^c	18.8 ± 4.5	.00
Verbally agitating behavior (n)	7^b	2	20^c	9	.00
Physical nonaggressive behavior (n)	7	5	17^c	7	.01
Physically aggressive behavior (n)	2	2	6	3	.35
Caregiving hours	2.2 ± 1.6^b	2.5 ± 1.9	4.5 ± 2.9^c	3.3 ± 1.8	.01
Informal support (n)	10	14	21	9	.19
Formal support	2.6 ± 1.7^b,e	1.9 ± 1.5^e	4.5 ± 2.5^c	4.3 ± 1.9	.00
Expressive support	27.7 ± 2.9^c,e	12.5 ± 3.0	26.9 ± 3.8^c,e	13.6 ± 5.2	.00
Burden	5.1 ± 4.1^b,e	5.8 ± 4.7^e	19.1 ± 5.4^c,e	30.1 ± 7.9	.00
Depression (n)	0^b,e	2^e	13^c	8	.00
Life satisfaction	4.04 ± 1.1	3.8 ± 1.9	3.8 ± 0.8	4.2 ± 2.3	.01

M ± SD.

Number; AD = Alzheimer’s disease; PD = Parkinson’s disease; PDD = Parkinson’s disease dementia; F = female; ADL = basic activities of daily living; IADL = instrumental activities of daily living.

Significantly different from getting by with support.

Significantly different from coping.

Significantly different from struggling.

Figure 2.

Dendogram using ward method.

Succeeding

This cluster comprised 24 PD (55.8% of all PD caregivers) and one AD caregiver. Care recipients in this cluster were the youngest (71.6 years) with moderate disease duration (6.2 years, p < .04). Caregivers were caring for none (68%) to mild (24%) cognitive impairment, high ADL ability, few IADL impairments, and reported 16 problem behavior. Caregivers provided 4 to 10 care hours per week, utilized close to three sources of formal support for the care recipient and received high levels of emotional support for themselves. Succeeding caregivers cared for less cognitive impairment (p = .00), more ADL and IADL impairment (p = .00) than the other clusters. They cared for less problem behaviors (p < .01) and their care recipients used less formal support (p = .00) than Getting by with Support and Struggling. Caregivers in this cluster reported higher emotional support than Coping and Struggling (p = .00) and had less burden than Getting by with support and Struggling (p = .00) and no depression.

Coping

This cluster comprised 28 AD (68.3% of all AD caregivers), two PD, and two PDD caregivers. Care recipients in this cluster were on average 73.8 years old and had the shortest disease duration (4.5 years, p = .00). Caregivers were caring for mild (59.3%) to moderate (37.5%) cognitive impairment, moderate ADL/IADL impairment, and reported nine problem behaviors. Coping had moderate cognitive and IADL declines, and low ADL and behavior stressors compared with the other clusters (p < .01). Caregivers provided 4 to 10 care hours per week and care recipients utilized two formal services. These care recipients used fewer formal services (p < .04) and caregivers cited fewer care hours and little emotional support (p < .002) compared with the other clusters. These caregivers had less burden and depression (6%) than Getting by with support (p < .02) and Struggling (p < .005).

Getting by with support

This cluster comprised 16 PDD (76.2% of all PDD caregivers), 14 PD (32.6% of all PD caregivers), and two AD caregivers. Care recipients were the oldest (76.8 years) and longest disease duration (10.9 years, p < .04). Caregivers cared mostly for persons with mild (46.9%) to moderate (31.3%) cognitive impairment, and included four caregivers of persons with severe dementia. Care recipients had moderate ADL ability, high IADL disability, and reported a total of 43 problem behaviors. Getting by with support cared for severe cognitive impairment (p = .00), greater IADL dependence (p = .00), and problem behaviors (p = .00) compared with Succeeding and Coping. Caregivers provided 21 to 25 hr care per week, care recipients utilized more formal services (n = 4) than Succeeding and Coping (p < .02), and caregivers had greater emotional support than Struggling (p = .00) and Coping (p = .00). These caregivers’ experienced moderate levels of burden (p = .00) and 40% were depressed.

Struggling

This cluster comprised 10 AD (24.4% of all AD caregivers), three PD, and three PDD caregivers. Care recipients in this cluster were on average 73.4 years old with moderate disease duration (6.3 years). Caregivers cared for persons with none (18%), mild (37.5%), moderate (37.5%), and severe (n = 1) dementia, moderate ADL ability, high IADL impairment, and reported a total of 19 problem behaviors. Struggling had moderate cognitive impairment (p = .00), greater IADL dependence than Succeeding (p < .02), and less problem behaviors (p < .004) compared with Getting by with Support. These caregivers provided 11 to 20 care hours per week, utilized five formal services and had little emotional support. These care recipients utilized more formal supports than Succeeding or Coping (p = .00) and caregivers had less emotional support than Succeeding and Getting by with support (p = .00). The greatest levels of burden (30.1 ± 7.9) and depression (50% met criteria for clinical depression) were seen in this group.

Comparing clusters, it is clear that when care stressors are mild-to-moderate, the amount of both formal and expressive support has little impact on caregiver experiences (i.e., Succeeding, Coping). However, as symptoms increase, the amount of formal support use also increases. More importantly, the amount of expressive support has the greatest impact when stressors are greater and influence whether caregiver negative experiences are moderate (Getting by with support) or severe (Struggling). For example, Getting by with support caregivers were utilizing available formal and emotional support to manage caring for considerable cognitive, functional, and behavioral stressors. Conversely, Struggling had similar stressors to Getting by with support but received less emotional support; as such, Struggling caregivers experienced greater burden and incidence of depression. Sixty-eight percent of all AD caregivers were clustered in Coping, that is, shorter care duration, care for mainly ADL stressors and little support; 56% of all PD caregivers clustered in Succeeding, that is, cared for mild stressors for moderate duration and received lots of emotional support; and 76% of all PDD caregivers clustered in Getting by, that is, cared for problematic behaviors for the longest duration and utilized lots of formal and expressive support. Struggling was composed mostly of AD caregivers (62.5% of cluster) who cared for persons with moderate-severe dementia and multiple behavior problems for a moderate duration. Moderate care hours, high formal support, and low emotional support were typified in this cluster.

The cluster analysis was rerun with the additional variable of “disease diagnosis.” The results were similar and produced the same four clusters. Only seven participants were allocated to different clusters based on this analysis; one AD caregiver moved from Coping to Succeeding, two PD caregivers moved from Getting by with support to Succeeding, and four PDD caregivers moved from Getting by with support to Struggling. These changes in caregiver allocation did not change the composition of the clusters and similar characteristics and comparisons between the groups were seen (full results of this analysis available from author by request).

Discussion

Exploration of comparative caregiver experiences across AD, PD, and PDD spouses has been limited although recently there is increased recognition of the prevalence, burden and management challenges of the nonmotor symptoms associated with PD. Understanding the relative importance of various demands on and supports for care needs and caregiver experiences can inform changes to current resources that ensure the person with AD, PD, or PDD and their spouse receive the type of assistance that will help them maintain a degree of independence for as long as possible. Our findings support the Stress Process model because access to increased support, especially emotional, in the presence of advanced symptoms moderated negative QoL experiences in these clusters.

Caregiver Profiles

The current study expands on knowledge of caregiver experiences across neurodegenerative groups by revealing different types of spousal caregiving experiences that go beyond disease diagnosis and take into consideration presenting stressors and use of available supports for caregiver health and well-being. Four clusters were typified based on mild, moderate, or severe stressors, the amount of support, especially emotional, and resulting burden and depression: Succeeding, Coping, Getting by with support, and Struggling. This has implications for clinicians and community organizations that serve these groups; notably, that not all caregivers for the same diagnostic group have the same needs for support. However, some diagnoses were more or less likely to fall in particular categories than others due to the nature of presenting stressors and support available; for example, PD in Succeeding, AD in Coping.

Bivariate results show group differences based on disease diagnosis. Among the caregivers in this study, AD caregivers cared for more persons with cognitive impairment and IADL dysfunction; PD caregivers managed more ADL dysfunction; and PDD caregivers cared for more persons with cognitive impairment, IADL dysfunction, and behavioral problems. PDD caregivers faced greater stressors; were significantly more burdened and depressed, experienced decreased life satisfaction; and were in most need of assistance compared with AD and PD caregiver groups (Table 1). While disease diagnosis may influence the presenting stressors and their impact on caregiver QoL experience, stressors cross diagnostic groups. In addition, the influence of expressive support from friends/family in moderating burden and depression in caregivers varies across disease groups. Thus, caregivers of persons with the same diagnosis may have very different experiences depending on the care demands and available support; more than disease diagnosis needs to be considered when addressing caregiver needs.

Group Differences

While we acknowledge the impact of disease diagnosis on caregiver outcomes, this study demonstrates that care demands, moderated by the amount/type of support received, have a greater contribution to caregiver subgroup differentiation. Caregivers managing the greatest symptoms had the greatest negative experiences (burden, depression), irrespective of diagnosis. The clusters Getting by with support and Struggling had the greatest symptom presentation, which necessitated greater care hours. Caregivers in the Getting by group cared for the greatest problem behaviors and IADL disability, yet the use of formal services and expressive support likely mitigated the negative impact on QoL in this group. The cluster Succeeding had the highest ADL impairment, least cognitive impairment and problem behaviors, and least burden and depression; while Struggling caregivers had less ADL impairment, more cognitive and behavioral issues, and the most negative QoL experience. This suggests the greater influence of cognition and behavior in the clustering of caregiver experience over basic ADL function. The importance of cognition and behavioral management to QoL reflects previous literature that shows an association between caregiver strain, behavior, and cognitive impairment (Allegri et al., 2006; Brodaty, Woodward, Boundy, Ames, & Balshaw, 2014; Conde-Sala et al., 2010a; Kim et al., 2012; Kudlicka et al., 2014; Lowery et al., 2000; Savundranayagam & Montgomery, 2010), while advancing motor symptoms have a lesser impact on caregiver strain in spouses compared with these nonmotor symptoms (Oguh, Kwasny, Carter, Stell, & Simuni, 2013). Left unmanaged, these symptoms affect QoL, care costs, and risk of institutionalization.

Getting by with support had high levels of expressive support and resource use, and also reduced levels of depression and burden compared with Struggling, who had similar behavior problems, greater cognitive impairment, and less support. Quality social support is linked to improved QoL among spouses and acts as a buffer among stressors that significantly influence caregiver experiences (Chappell & Reid, 2002; Pearlin et al., 1990; Savundranayagam, 2014). This study shows that the negative experience of caring for someone with behavior and cognitive impairment is lessened when the caregiver has support from family/friends and the care recipient utilizes available formal services. Increased social support is important in mitigating caregiver burden in spouse caregivers, as caring for a spouse with dementia is often accompanied by a perceived change in the spousal relationship (Paradise et al., 2015). Spouses who were once confidantes and sources of emotional support for one another may find their partner no longer fulfills that role. As such, the quality of support a spouse caregiver receives from others could become more relevant.

The clusters with more stressors and negative experience had greater care hours (Getting by, Struggling) than Succeeding and Coping. Increased care hours were related to increased caregiver burden in this study. Care hours did not differ between disease groups, but differed between clusters. The caregivers in the Coping cluster, with the shortest care duration, were able to manage the associated stressors more independently in fewer hours with little support and impact on their QoL experience. Studies show care experiences, burden and satisfaction may change as the disease progresses (Andrén & Elmståhl, 2005; Conde-Sala et al., 2010a; Contador, Fernández-Calvo, Palenzuela, Miguéis, & Ramos, 2012). Due to the progressive nature of neurodegeneration, a longitudinal analysis of how caregivers move between types of caregiving experiences is warranted.

Life satisfaction is a measure of caregivers’ well-being and may provide protection from the negative consequences associated with caring (Robertson, Zarit, Duncan, Rovine, & Femia, 2007). Life satisfaction was similar across all clusters; however, depression and burden changed with stressor type, severity, informal support, and service use. This supports caregiver burden and well-being as distinct constructs and they can be burdened without impact on satisfied they feel about life (Chappell & Reid, 2002).

Limitations

There are several limitations, although this is one of the few studies to compared AD, PD, and PDD spouse caregivers. The AD caregivers were recruited from the ADTI, specific to those prescribed ChEI; however, it was deemed an appropriate comparison group as the clinical effectiveness of ChEI is controversial at best and is currently prescribed for mild to moderate dementia, not targeted to any subgroup (Chappell et al., 2014). Although this study provides important findings, it was cross sectional and may be nonrepresentative of all AD, PD, or PDD spousal caregivers. Moreover, given relational distinctiveness that characterize spouse caregivers, the generalizability of findings cannot be assumed for adult children or other relationships. The difficulty finding caregivers of persons with a PDD diagnosis to participate resulted in a relatively small sample for this group. There is potential for type II error; however, unequal group sizes were accounted for in our analyses.

Clinical Implications

The present study has practical implications for supporting spouse neurodegenerative caregivers and theoretical implications concerning the impact of symptom and support on QoL. Identifying caregivers at highest risk for reduced QoL is of clinical relevance given that a number of influences, such as perceived social support, can help mitigate negative care experiences. Not all persons diagnosed with the same disease suffer from the same symptoms, and, as such, resources for caregivers must match needs. This study shows that going beyond disease diagnosis needs to be taken into consideration in the structure of the health care system, where disease diagnosis is the main mode of identification. It is essential for clinicians to communicate directly with spouses about their needs. A more complete understanding of the influences on caregiver experiences across diseases will improve management of burden by providing reliable knowledge to clinicians that can be used to assess caregivers’ situations and optimize care of patient and spouse caregiver. Improved evaluation of caregiver experiences can guide policy makers in the allocation of support services to this diverse and growing population.

Awareness of caregiver experiences can inform spouses for their unique needs and may result in the promotion of appropriate coping strategies that can reduce caregiver distress, behavioral disturbance, enhance care recipient function, delay institutionalization, and improve self-esteem (Brodaty & Arasaratnam, 2012; Brodaty, Mittelman, Gibson, Seeher, & Burns, 2009; Mittelman, Brodaty, Wallen, & Burns, 2008). Examples include informal help, relevant skill-training, peer support groups, stress management techniques, organizational resources, and informed care plans. Improved clinical care and targeted programming will result in the dual benefit of improving caregiver well-being and reducing the likelihood of care recipient institutionalization. Tailored health care services to help caregivers manage demands associated with neurodegenerative disease are critical for QoL.

Footnotes

Acknowledgements

The authors acknowledge the contribution of their participants and the support of their funders.

Author Contributions

The corresponding author accepts full responsibility for this work, has access to the data, and controlled the decision to publish. All coauthors have read the article and are aware of the submission. All named authors have made a substantial contribution:

• K.P.R.: (a) conception, design, recruitment/data collection (PD/PDD), analysis, and interpretation of data (ADTI/PD/PDD); (b) drafting of article, revising it critically; (c) approval of version to be published.

• N.L.C.: (a) conception, design, and interpretation of data (ADTI/PD/PDD); (b) revising the article critically for important intellectual content; (c) approval of version to be published.

Authors’ Note

All inferences, opinions, and conclusions drawn in this publication are those of the ADTI researchers, and do not reflect the opinions or policies of the BC Ministry of Health. The funding bodies had no involvement in the design, in the collection, analysis, and interpretation of data; in the writing of the manuscript; and in the decision to submit the manuscript for publication.

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: K.P.R. was supported by a postdoctoral fellowship award from the Canadian Institutes of Health Research (CIHR): Gender, Work and Health (2012-2014) and Michael Smith Foundation for Health Research (2013-2016). Part of this work was also supported by the Pharmaceutical Services Division, Ministry of Health, Provincial Government of British Columbia as part of the Alzheimer’s Drug Therapy Initiative (ADTI) for the purpose of developing evidence for the use of ChEI treatment in the community.

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