The prevalence and risk factors of apathy among the Canadian long-term care residents with Alzheimer's disease and related dementias

Abstract

Background

Apathy is a prevalent and debilitating neuropsychiatric symptom among persons living with Alzheimer's disease and related dementias, particularly those residing in long-term care facilities (LTCF). Despite its profound effects on the quality of life for both residents and their caregivers, apathy remains underrecognized and poorly understood in the context of dementia care.

Objective

To investigate the prevalence and biopsychosocial characteristics of apathy among newly admitted residents with dementia in Canadian LTCF using an Apathy Index derived from the interRAI Minimum Data Set (MDS) 2.0.

Methods

This cross-sectional study analyzed data from newly admitted residents with dementia from various LTCF (N = 97,789) across seven Canadian provinces between 2015 and 2019. Logistic regression analysis was performed to determine the relationship between apathy and multiple variables including sociodemographic and clinical variables. The biopsychosocial model of health was used to guide analysis.

Results

The prevalence rate of apathy among the Canadian long-term care residents with Alzheimer's disease and related dementias was 13.1%. Apathy was associated with various variables including male sex, pain, use of psychotropics, high Activity of Daily Living Self-Performance Hierarchy Scale scores, depression, aggression, severe cognitive impairment, and insomnia. Preferences for certain activities such as card games, art and craft, reading, music and exercise were inversely related to apathy while gardening was not.

Conclusions

By shedding light on this complex phenomenon within a Canadian context, we recommend that targeted interventions and improved care strategies to enhance the well-being of persons living with dementia should be prioritized in LTCF.

Keywords

Alzheimer's disease apathy biopsychosocial Canada cross-sectional study dementia interRAI MDS 2.0 nursing homes older adults prevalence

Introduction

Dementia, a chronic and progressive syndrome characterized by cognitive impairment and functional decline, poses a significant public health challenge in the twenty-first century. Dementia affects over 47 million people worldwide and as the global population ages, it is anticipated that the prevalence of dementia will triple by 2050.¹ This will have significant implications for healthcare systems worldwide. A report by the Alzheimer Society of Canada (2022)² estimated that 597,300 Canadians were living with dementia in 2020. This number is expected to increase to 1.7 million by 2050.² This escalating trend highlights the need for extensive research into the various facets of dementia, including its lesser known but equally debilitating symptom, apathy.³

Apathy, marked by a reduction in motivation or interest, goal-directed actions, affect and/or social interactions, is one of the most prevalent and clinically significant behavioral symptoms observed in people living with dementia, especially those in long term care facilities (LTCF).^4–7 The prevalence rates of apathy among people living with dementia range from 12% to 100%, varying greatly depending on methodologies for apathy assessment, the severity of dementia, and co-morbidities.^8–11 In a United States (US) study, for instance, it was observed that 84.1% of LTCFs’ residents with dementia had apathy.¹² A comprehensive review found that the frequency of apathy was 27% among community dwelling population of 329 individuals without dementia and 69% among 162 residents with dementia admitted to a specialized dementia unit.¹³ A German study also showed that 7% of cognitively intact residents, 8% of those with mild cognitive impairment, and 85% of residents with dementia exhibited apathetic behaviors.¹⁴ In a cross-sectional, observational study carried out in the Netherland which involved a sample of LTCF residents with stroke, the result demonstrated that apathy was prevalent in 28% of this population.¹⁵ Tagariello (2009)¹⁶ also reviewed the literature on apathy (but didn’t include the previous studies) in dementia and noted that it is the most common neuropsychiatric syndrome in Alzheimer's disease, affecting 19-76% of residents, and difficult to distinguish from depression.

Studies have investigated the association between apathy and various neuropsychiatric symptoms such as depression,^15,17,18 anhedonia,¹⁷ fatigue,^19,20 and agitation²¹ among LTCF residents with dementia but the results are mixed. For example, a study involving people with Alzheimer's disease found that apathy is strongly associated with depression.¹³ In contrast, another study reported that apathy is not clinically significantly associated with depression.¹⁵ Additionally, a study by Jao et al. (2019) examining the relationship among apathy, depression and agitation, no relationship was found between apathy and these disorders.³ Furthermore, certain contextual factors have been linked with apathy among LTCF residents with dementia. For example, Jao et al. (2015)²² found that care environments with clear and sufficient stimulation were significantly associated with lower resident apathy levels. Engagement in activities has also been inversely associated with apathy in dementia, indicating that increased activity participation among residents leads to reduced symptoms of apathy.²³ Vilalta-Franch (2012)²⁴ identified the use of antipsychotic medication as the sole risk factor for apathy in dementia. Moreover, persons living with dementia who resided with someone other than their spouses were found to be more susceptible to apathy compared to those living with their spouses.²⁵

Despite the significance of apathy among residents living with dementia, its associative characteristics are still not entirely understood.⁷ More importantly, research on apathy among the Canadian LTCF residents with dementia is limited. Further, while existing studies have primarily focused on the neurobiological underpinnings of apathy in dementia, including changes in specific brain regions and neurotransmitter systems,^26,27 a comprehensive study linking resident-related biological, psychological, and social characteristics that increase the risk of apathy is lacking. Additionally, most studies did not prioritize apathy as the focus, and research examining factors associated with apathy in dementia, distinct from depression or other behavioral issues, remains scarce.^28,29 These gaps underscore the need for a more holistic investigation into apathy in dementia among LTCF residents, particularly in the Canadian context given its diverse population and unique healthcare policies.³⁰ The purpose of this study was to examine through the lens of the biopsychosocial model of care,³¹ the prevalence and the associative biopsychosocial characteristics of apathy among the Canadian LTCF residents with dementia (Alzheimer's and non-Alzheimer's), drawing from the MDS 2.0 dataset. Such research is instrumental to inform design of targeted interventions and clinical practice guidelines to best identify, manage, and possibly prevent apathy in this population.

Methods

Settings and participants

This cross-sectional study used secondary data derived from MDS 2.0 dataset collected through the Continuing Care Reporting System (CCRS) at the Canadian Institute of Health Information (CIHI) across six provinces (Alberta, British Columbia, Manitoba, Nova Scotia, Saskatchewan, and Ontario) and one Territory (Yukon) in Canada (N = 97,786). The MDS 2.0 is a mandated standardized assessment instrument for use in most LTCF across Canada and provides comprehensive personal-level information about residents that informs decision-making in developing a care plan that reflects their needs, preferences, and strengths.³² The assessment is completed by trained healthcare staff (usually staff nurses) using information from multiple sources including observation, resident interview, medical records, and consultation with team members and other healthcare professionals, including attending physicians, social workers, physical, occupational, speech, or recreation therapists, dieticians, and pharmacists.^32,33

Embedded in the MDS 2.0 are the outcome scales, also known as clinical assessment protocols (CAPs). Included in this study are the Cognitive Performance Scale (CPS) which monitors changes in cognitive status³⁴ and consisted of five items including comatose, short-term memory, cognitive skills for daily decision making, express communication and eating.³⁵ The score ranges from 0–6. This score was recoded into three groupings: 0–1 (no/mild impairment), 2–3 (moderate impairment), and 4–6 (severe impairment);^36–40 the Depression Rating Scale (DRS) assesses mood and behavior.⁴¹ The DRS comprises of seven items including negative statements, persistent anger, expression of unrealistic fears, repetitive health complaints, repetitive anxious complaints, sad, pained, worried facial expression; and crying and tearfulness. The score on this scale ranges from 0–14. This was recoded into 3 levels: 0–2 (no/mild), 3–5 (moderate), and 6–14 (severe).⁴² A score of 3 or more on the DRS may indicate a potential or actual depression symptoms;³⁴ the Activity of Daily Living Self-Performance Hierarchy Scale (ADL-hierarchy) reflects the process of resident's disability by grouping ADL performance into different stages: early loss (personal hygiene), middle loss (toileting and locomotion), and late loss (eating).⁴³ The score ranges from 0 (independent) to 6 (total dependence). The score was recoded as 0–1 (no loss), 2–3 (moderate loss) and 4–6 (severe loss); the Aggressive Behavior Scale (ABS) measures aggression, and includes four items-verbally abusive, physically abusive, socially inappropriate/disruptive behavior and resists care.³⁴ The score ranges from 0–12.³³ This score was recoded into three categories: 0–2 (no/mild), 3–5 (moderate), and 6–12 (severe), and the pain scale which measures the frequency and intensity of pain among the residents. The scores range from 0 to 3 with higher values indicating severe pain.^44,45 The sample for this study included residents diagnosed with dementia who participated in the admission assessments of the MDS 2.0 between April 2015 and March 2019. Excluded from the study were residents with missing data, those in a comatose state, or those without dementia diagnosis. Selection of variables was based primarily on the definition of each component of the biopsychosocial model of care as proposed by Engel (1977),³¹ availability of variables, gaps identified in extant literature and co-morbidities of dementia such as depression, anxiety, and cognition.^13,46,47 In the MDS 2.0 assessment, the diagnosis of dementia and comorbidities is based on the International Statistical Classification of Diseases and Related Health Problems (ICD-10) as published by the World Health Organization (WHO).⁴⁸

Apathy measures

We used two items from the MDS 2.0, heretofore referred to as the Apathy Index to measure apathy. Each of these two items were originally scored by CCRS as follows: 0 = Indicator not exhibited in last 30 days; 1 = Indicator of this type exhibited up to 5 days a week; 2 = Indicator of this type exhibited daily or almost daily (6, 7 days a week). We converted these two items into a dichotomous variable. Thus, a score of 0 indicates non-apathetic and 1 is apathetic. This classification is based on the framework for apathy assessment proposed by Volicer et al. (2013)⁴⁹ which they referred to as the ‘Apathy Scale’. According to Volicer et al. (2013),⁴⁹ the Apathy Scale measures apathy by focusing on two specific items from the MDS 2.0 including withdrawal from activities of interest and reduced social interaction. In this study, apathy was conceptualized as the presence of one or both two items suggesting that a score of 0 is non-apathetic and 1 is apathetic. The study further cited the reliability of the apathy scale as alpha values of 0.88 to 0.89. These values suggest a high level of internal consistency for the items measuring apathy within the MDS 2.0 meaning that it measures the same underlying concept of apathy consistently across different assessments. Additionally, these two items are core symptoms of apathy included in the screening questions of the Neuropsychiatric Inventory and have also demonstrated a high degree of internal consistency.⁵⁰ Utilizing instruments that assess one or more domains of apathy can potentially enhance targeted treatment of apathy in dementia residents.⁷

Theoretical framework

Taking into account the combined effects of biological, psychological, and social factors on apathy, this study was grounded in the biopsychosocial model as its theoretical basis.^31,51–53 As highlighted by Engel (1977),³¹ biological factors encompass genetic influences, neurochemical processes, and other physiological aspects that contribute to the development and maintenance of health and disease; psychological factors relate to an individual's mental processes and behavior that influence health and disease, and social factors refer to the broad range of influences stemming from the societal and environmental context in which individuals live. Accordingly, variables were categorized as follows: biological (age, sex, pain, use of psychotropic medications and ADL-hierarchy), psychological (DRS, CPS, ABS, insomnia, and wandering), and social (language, marital status, and activity preferences) variables.

Statistical analyses

Analysis of data involved the use of SAS software version 9.4.⁵⁴ Descriptive statistics were conducted to describe the characteristics of the study sample. Bivariate analyses used chi-square to determine the significance of the relationship of apathy with various variables based on findings from existing literature or gaps identified in the literature. Logistic regression was conducted to determine the association between apathy and various variables that are associated with apathy in dementia. The prevalence of apathy was defined as the percentage of LTCF residents with dementia with an apathy score of 1. An alpha level of p < 0.05 was considered statistically significant.

Results

Table 1 shows the socio-demographics of the study sample. Out of the total sample of 97,786, most were residents with non-Alzheimer's dementia (82%, n = 80,170). More than half of the sample were female (64%) and 53% were aged 85 years and older, 64% were never married/widowed/divorced/separated, 14% lived alone before admission, 84% were English speakers, 70% lived in a large LTCF (over 100 beds), and the majority lived in Ontario (57%). Over two-thirds participated in the assessment (79%), 66% were prescribed psychotropic (anti-depressants, hypnotics, anti-anxiety, and anti-psychotics) medications and 24% experienced mild pain. Residents have various comorbidities of neuropsychiatric disorders including depression (24%), anxiety disorders (11.5%), Parkinson's disease (5.8%), multiple sclerosis (0.3%), Huntington's chorea (0.1%), amyotrophic lateral sclerosis (0.1%), manic depressive (1.4%), schizophrenia (1.3%) and traumatic brain injury (0.9%).

Table 1.

Socio-demographics of newly admitted residents with dementia assessed between 2015 and 2019 by status of apathy.

	Total sample 100% (N = 97,786)	Apathetic13.1% (n = 12,818)	Non-apathetic86.9% (n = 84,968)	*p
Dementia types
Alzheimer's	18 (17,616)	12.3 (2173)	87.7 (15,443)	0.0008
Non-Alzheimer's	82 (80,170)	13.3 (10,645)	86.7 (69,525)
Age at admission (y)
less than 65	2.7 (2652)	16.8 (445)	83.2 (2207)	<0.0001
65–74	10.1 (9859)	15.5 (1527)	84.5 (8332)
75–84	33.9 (33,119)	13.2 (4374)	86.8 (28,745)
85 and over	53.3 (52,156)	12.4 (6472)	87.6 (45,684)
Sex
Female	64.3 (62,861)	12.6 (7925)	87.4 (54,936)	<0.0001
Male	35.6 (34,838)	14 (4885)	86 (29,953)
Other	0.1 (87)	9.2 (8)	90.8 (79)
Marital status
Married	32.8 (27,913)	12.3 (3441)	87.7 (24,472)	<0.0001
Never married/widowed/ separated/divorced	63.9 (54,458)	12 (6555)	88 (47,903)
Not specified	3.4 (2851)	13.5 (385)	86.5 (385)
Lived alone before entry to LTCF
No	86.2 (79,231)	12.9 (10,238)	86.3 (68,993)	0.4014
Yes	13.8 (12,675)	13.2 (1672)	86.8 (11,003)
Province of LTCF
Alberta	12.1 (11,861)	19.5 (2309)	80.5 (9552)
British Columbia	19.2 (18,896)	17.6 (3319)	82.4 (15,677)	<0.0001
Manitoba	4.6 (4479)	14.5 (651)	85.5 (3828)
Newfoundland and Labrador	2 (1988)	19.7 (391)	80.3 (1597)
Ontario	57.2 (55,969)	8.9 (4977)	91.1 (50,992)
Saskatchewan	4.6 (4464)	26 (1160)	74 (3304)
Yukon	0.1 (129)	8.5 (11)	91.5 (118)
Language
English	84.4 (82,549)	13.7 (11,271)	86.4 (82,549)	<0.0001
French	2.4 (2345)	12.1 (284)	87.9 (2061)
Other	13.2 (12,892)	9.8 (1263)	90.2 (11,629)
Facility size
Large (100 + beds)	70.8 (69,244)	12.2 (8321)	88 (60,923)	<0.0001
Medium (30–99 beds)	27.2 (26,625)	15.5 (4115)	84.5 (22,510)
Small (1–29 beds)	2 (1917)	19.9 (382)	80.1 (1535)
Insomnia
Not exhibited in the last 30 days	83.9 (81,962)	11.5 (9429)	88.5 (72,533)	<0.0001
Exhibited up to 5 days per week	14.3 (13,983)	20.3 (2833)	79.7 (11,150)
Exhibited daily or almost daily	1.9 (1841)	30.2 (556)	69.8 (1285)
Wandering
No	86.1 (84,168)	13 (10,958))	87 (73,214)	0.0308
Yes	13.9 (13,618)	13.7 (1864)	86.3 (11,754)
PAIN
No pain (0)	67.9 (66,421)	12 (7989)	88 (58,432)	<0.0001
Mild (1)	23.7 (23,156)	13.7 (3179)	86.3 (19,977)
Moderate (2)	7.6 (7427)	19.5 (1451)	80.5 (5976)
Severe (3)	0.8 (782)	25.4 (199)	74.6 (583)
Use psychotropic medications
No	33.9 (33,163)	10.5 (3486)	89.5 (29,677)	<0.0001
Yes	66.1 (64,623)	14.4 (9332)	85.6 (55,291)
Resident's participation in assessment
No	22 (21,493)	18.5 (3977)	81.5 (17,516)	<0.0001
Yes	78 (76,293)	11.6 (8841)	86.4 (67,452)
Comorbidities
Depression
No	75.8 (74,119)	12.5 (9234)	87.5 (64,885)	<0.0001
Yes	24.2 (23,667)	15.1 (3584)	84.9 (20,083)
Anxiety disorders
No	88.5 (86,497)	12.9 (11,126)	87.1 (75,371)	<0.0001
Yes	11.5 (11,289)	15 (1692)	85 (9597)
Parkinson's disease
No	94.2 (92,099)	13.2 (12,116)	86.8 (79,983)	0.08
Yes	5.8 (5687)	12.3 (702)	87.7 (4985)
Multiple sclerosis
No	99.7 (97,481)	13.1 (12,779)	86.9 (84,702)	0.87
Yes	0.3 (305)	12.8 (39)	87.2 (266)
Amyotrophic lateral sclerosis
No	99.9 (97,721)	13.1 (12,810)	86.9 (84,911)	0.85
Yes	0.1 (65)	12.3 (8)	87.7 (57)
Huntington's chorea
No	99.9 (97,696)	13.1 (12,801)	86.9 (84,895)	0.10
Yes	0.1 (90)	18.9 (17)	81.1 (73)
Manic depressive
No	98.6 (96,461)	13.1 (12,623)	86.9 (83,838)	0.08
Yes	1.4 (1325)	14.7 (195)	85.3 (1130)
Schizophrenia
No	98.7 (96,525)	13.1 (12,613)	86.9 (83,912)	0.0009
Yes	1.3 (1261)	16.3 (205)	83.7 (1056)
Traumatic brain injury
No	99.1 (96,885)	13.1 (12,669)	86.9 (12,669)	0.0022
Yes	0.9 (901)	16.5 (149)	83.5 (752)

*chi-squared p value.

Figure 1 shows the activity preferences of the study sample. Majority of the residents preferred listening to music (79%) to other types of activities including talking (78%), watching TV (65%), exercise (43%), card games (36%), spiritual activities (36%), reading (31%), art and craft (23%), trips (15%), gardening (14%), helping others (13%), and walking (4%).

Figure 1.

Activity preferences of the Canadian LTCF newly admitted residents with dementia (N = 97,786) assessed between 2015 and 2019.

Prevalence of apathy

The prevalence of apathy among LTCF residents with dementia was 13.1% (n = 12,818). Apathy was more prevalent among residents who were younger than 65 years of age compared to those who were 85 years and over (17% versus 12%, p = < 0.0001). English speakers exhibited a higher prevalence of apathy compared to residents speaking other languages (14% versus 10%, p = < 0.0001). The prevalence rate of apathy was higher among residents living in small LTCF compared to those in large LTCF (20% versus 12%, p = < 0.0001). No significant difference was found in the prevalence of apathy between residents who lived alone before admission and those who lived with a spouse or family (13% versus 13%, p = 0.40). Apathy was slightly more frequent among residents who exhibited wandering behaviors compared to those who did not (14% versus 13%, p = 0.03). The prevalence of apathy was higher among residents who experienced severe pain compared to those with no pain symptoms (25% versus 12%), and residents who exhibited insomnia daily showed a higher prevalence of apathy compared to those who did not (30% versus 12%).

Those who indicated preferences for various types of activities have a lower frequency of apathy than those who did not (Figure 2). These activities included card games (10% versus 15%, p = < 0.0001), helping others (8% versus 14%, p = <0.0001), exercise (9% versus 14%, p = < 0.0001), trips (9% versus 14%, p = < 0.0001), art and craft (9% versus 14%, p = < 0.0001), spiritual activities (10% versus 15%, p = < 0.0001), gardening (10% versus 13%), reading (10% versus 14%, p = < 0.0001), walking (10% versus 15%, p = < 0.0001), talking (11% versus 19%, p = < 0.0001), music (11% versus 20%, p = < 0.0001), and watching TV (12% versus 17%, p = < 0.0001). When stratified by cognitive performance (Supplemental Table 1), apathy prevalence across different activities increases with the severity of cognitive impairment.

Figure 2.

Prevalence of apathy among newly admitted Canadian LTCF residents who indicated preferences for different activities compared to those who did not.

Residents who were diagnosed with co-morbid neuropsychiatric disorders showed a higher prevalence of apathy than those without these disorders including depression (15% versus 13%, p = < 0.0001), anxiety (15% versus 13%, p = < 0.0001), manic depressive (15% versus 13%, p = 0.08), schizophrenia (16% versus 13%, p = 0.0009), and traumatic brain injury (17% versus 13%, p = 0.02), and Huntington's chorea (19.3% versus 14.8%, p = 0.10). However, apathy was slightly less frequent among those with co-morbid certain types of neurodegenerative diseases than those without, but the results were statistically insignificant. These included multiple sclerosis (13% versus 13.1%, p = 0.87), Parkinson's disease (12% versus 13%, 0.08), and amyotrophic lateral sclerosis (12% versus 13%, p = 0.85).

Biopsychosocial characteristics of apathy in dementia

Table 2 displays the variables that were associated with apathy. Following the biopsychosocial model of care as a theoretical framework to guide analysis, biologically, the characteristics associated with apathy were male sex (odds ratio [OR] = 1.13, 95% confidence interval [CI]:1.09–1.18, p < 0.0001), pain (OR = 1.16, 95% CI: 1.11–1.21, p < 0.0001 for mild; OR = 1.72, 95% CI: 1.66–1.88, p < 0.0001 for moderate; OR = 2.44, 95% CI: 2.07–2.87, p < 0.0001 for severe), use of psychotropics (OR = 1.39, 95% CI: 1.00–1.14, p < 0.0001), and high ADL-hierarchy score (OR = 1.07, 95% C1: 1.00–1.114, p = 0.439) . Among the psychological variables, depression (OR = 2.05, 95% CI: 1.95–2.14, p < 0.0001 for moderate; OR = 3.24, 95% CI: 3.03–3.46, p < 0.0001 for severe), aggression (OR = 1.37, 95% CI: 1.30–1.44, p < 0.0001 for moderate; OR = 1.51, 95% CI: 1.41–1.62, p < 0.0001 for severe), severe cognitive impairment (OR = 1.15, 95% CI: 1.06–1.24, p = 0.0009), and insomnia (OR = 1.14, 95% CI: 1.34–1.48 for exhibited up to 5 days; OR = 2.0, 95% CI: 1.80–2.23 for exhibited daily, p < 0.0001). In relation to social variables, the analysis demonstrated that preferences for certain activities except gardening were inversely associated with apathy (all p < 0.0001).

Table 2.

Logistic regression modelling the biopsychosocial characteristics of apathy among the newly admitted Canadian LTCF residents with dementia (n = 97,786) assessed between 2015 and 2019.

Variables	OR	(95% CI)	p
Biological
Age group (y)
Under 65	Reference
65–74	0.92	0.82–1.03	0.14
75–84	0.78	0.70–0.86	<0.0001
85+	0.75	0.68–0.84	<0.0001
Sex
Female	Reference
Male	1.13	1.09–1.18	<0.0001
Other	0.71	0.34–1.47	0.36
Pain
No pain	Reference
Mild	1.16	1.11–1.21	<0.0001
Moderate	1.72	1.66–1.88	<0.0001
Severe	2.44	2.07–2.87	<0.0001
Use of psychotropics
No	Reference
Yes	1.39	1.33–1.45	<0.0001
ADL hierarchy
Low (0–1)	Reference
Medium (2–3)	0.98	0.92–1.04	0.54
High (4–6)	1.07	1.00–1.14	0.04
Psychological
DRS (Depression)
No/Mild (0–2)	Reference
Moderate (3–5)	2.05	1.95–2.14	<0.0001
Severe (6–14)	3.24	3.03–3.46	<0.0001
CPS (Cognitive impairment)
No/Mild (0 −1)	Reference
Moderate (2–3)	0.93	0.86–1.00	0.06
Severe (4–6)	1.15	1.06–1.24	0.0009
ABS (Aggression)
No/Mild (0–2)	Reference
Moderate (3–5)	1.37	1.30–1.44	<0.0001
Severe (6–12)	1.51	1.41–1.62	<0.0001
Insomnia
Not exhibited	Reference
Exhibited up to 5 days	1.41	1.34–1.48	<0.0001
Exhibited daily or almost daily	2.0	1.80–2.23	<0.0001
Wandering (Ref = No)	0.99	0.94–1.05	0.75
Social
Language
English	Reference
French	0.97	0.85–1.10	0.59
Other	0.63	0.59–0.68	<0.0001
Marital status
Married	Reference
Never married/widowed/ separated/divorced	1.01	0.97–1.06	0.62
Unspecified	1.08	0.98–1.21	0.19
Activity preferences (Reference = Yes)
Card games/other games	1.16	1.12–1.22	<0.0001
Art and Craft	1.11	1.04–1.15	0.0009
Exercise/sports	1.39	1.32–1.46	<0.0001
Music	1.43	1.36–1.50	<0.0001
Reading	1.08	1.03–1.13	0.0035
Spiritual activities	1.21	1.15–1.27	<0.0001
Trips	1.16	1.08–1.25	0.0013
Walking	1.08	1.03–1.13	0.0018
Watching TV	1.22	1.16–1.27	<0.0001
Gardening	0.88	0.82–0.96	0.0012
Talking	1.50	1.43–1.57	<0.0001
Helping others	1.17	1.08–1.26	<0.0001

OR: adjusted odds ratio; CI: confidence interval.

Discussion

The prevalence of apathy among newly admitted residents with dementia in Canadian LTCF was 13.1%. This prevalence is consistent with existing literature, which reports apathy prevalence rates ranging from 11% to 40% in dementia populations^13,55 but is lower than the frequencies (23.1% and 56%) observed in two Dutch studies^56,57 and a systematic review of 28 studies which demonstrated the prevalence rate of 36%.⁵⁸ These discrepancies could be due to differences in the stages of dementia of the participants, or the methodologies used to assess symptoms. The variation in prevalence rates across studies highlights the importance of standardized assessment tools and diagnostic criteria for apathy. Moreover, it could have been that apathy was perceived as a symptom of dementia, and therefore, under or overrated.^59,60

Consistent with studies examining apathy in young onset dementia^57,61 but in contrast to previous studies investigating apathy in late onset dementia,^13,62 a small percentage of our sample falls into the age group of less than 65 years (2.7%); however, they comprise a sizeable proportion exhibiting apathy in comparison with those who are 85 years and over (17% versus 12%). In addition, our analysis found that apathy prevalence was slightly higher in non-Alzheimer's dementia in comparison with Alzheimer's dementia (13% versus 12%). This may suggest the difference in neuroanatomical changes between these types of dementias and reflect the type of dementia common in this population.⁶³ These findings underscore the importance of age and disease specific interventions in mitigating apathy in this population.

Although females constitute most of the population, the proportion of individuals with apathy in this sex category is slightly lower than males. This is congruent with the findings reported by Holtta et al. (2012)⁵⁶ where apathy was observed to be more prevalent in males than females. Previous research has indicated that when compared to females, males with dementia often exhibit more severe neuropsychiatric symptoms, including apathy, potentially due to differences in diseases in disease progression.^21,24 In addition, we found that marital status does not have a significant impact on the likelihood of apathy among newly admitted Canadian LTCF residents with dementia. One possible explanation is that while marital status might traditionally be seen as a proxy for social support, residents in LTCF may receive various forms of social interaction and support from staff, other residents, and structured activities that mitigate the lack of a spouse or partner or it could be that residents may adapt to the structured environment, where regular interaction with care staff and communal activities provide substantial social support, potentially reducing differences between married and unmarried residents.

In congruence with previous research, our analysis showed that apathy was more prevalent among residents with co-morbid neuropsychiatric disorders, including depression, anxiety disorder, traumatic brain injury, and schizophrenia.^{13,15,16,47,64–66} This highlights the complex interplay between apathy and other neuropsychiatric conditions in residents with dementia and underscores the need for a multidisciplinary approach to dementia care. This may include the involvement of psychiatrists, psychologists, neurologists, and other healthcare professionals in developing and implementing care plans. It is also important to note that although depression often co-occurs with apathy in dementia, these two constructs can be differentiated.^16,67–69 Apathy is marked by a noticeable lack of effort and a dependency on others to organize activities. Individuals with apathy show little interest in learning new things or engaging in new experiences. They exhibit a marked indifference toward their personal problems and maintain an unchanging emotional affect.⁷⁰ In contrast, depression is characterized by persistent tearfulness, sadness, feelings of worthlessness and hopelessness.^70,71 Additionally, apathy is often related to neurodegenerative changes, particularly in areas of the brain associated with motivation and executive function, whereas depression involves a broader range of emotional and psychological symptoms that can sometimes be alleviated with antidepressants.²⁸

With regards to biological characteristics of apathy, our findings revealed that males have significantly higher odds of experiencing apathy compared to females (OR = 1.42, 95% CI = 1.25–1.62, p < 0.0001). Previous research has indicated that males with dementia often exhibit more severe neuropsychiatric symptoms, including apathy, potentially due to differences in disease progression.^21,24 In addition, the significant association between severe pain ad increased odds of apathy is consistent with existing literature.¹³ Effective pain management is crucial in dementia care to improve resident's outcome. The strong association between use of psychotropic medications and apathy highlights the importance of regular medication reviews to minimize adverse effects while managing neuropsychiatric symptoms.⁷² Evidence has shown that the use of psychotropics in dementia is complicated by increased risks of mortality, falls, and cardiovascular events.⁷³ Therefore, careful assessment and monitoring are needed to balance the potential benefits with these risks.

Among the psychological variables, our study demonstrates that moderate to severe depression, severe aggression and severe cognitive impairment significantly increased the odds of apathy. This aligns well with previous studies,^13,74,75 highlighting the influence of cognitive and behavioral health on the overall well-being of residents with dementia.⁷⁶ This finding further validates our current understanding of apathy as a distinct symptom requiring proper investigation and intervention.^27,77 Furthermore, the association between insomnia and increased apathy is consistent with previous research emphasizing the need for addressing sleep issues through careful monitoring using technologies such as ambulatory actigraphy.⁷⁸ Social factors, particularly activity preferences, play a notable role in the health outcomes of residents with dementia. Our study found that a lack of preference for activities significantly increases the odds of apathy among these residents. This finding supports existing literature which emphasizes the importance of social engagement and personalized activities in mitigating apathy.^23,79 Guidance and better activities of interest can lead to enhanced engagement time among residents with dementia.⁸⁰ Ensuring that residents have access to meaningful and engaging activities tailored to their interests can help mitigate apathy and improve their overall quality of life. The role of care staff in motivating residents experiencing apathy to participate in activities cannot be over-emphasized.⁸⁰

Strengths and limitations

To the best of the authors’ knowledge, this is the first Canadian study that used an apathy scale derived from the MDS 2.0 dataset to measure apathy and its associated biopsychosocial characteristics in a large sample within LTCF setting. The inclusion of several variables from the MDS 2.0 provides a robust and multidimensional understanding of the symptoms of apathy in the context of dementia and enhances the generalizability of the findings to this context. However, while this cross-sectional study provides valuable insights, it also has limitations, particularly the inability to establish causality due to the simultaneous measurement of exposures and outcomes. Longitudinal studies are necessary to confirm the temporal relationships and causative factors for apathy in dementia. Furthermore, future research should explore the effectiveness of specific interventions in reducing apathy and improving the quality of life of people living with dementia in LTCF. It is also of note that given the limitations of the MDS 2.0 dataset, some pertinent biological variables associated with apathy in dementia such as apolipoprotein epsilon 4 allele (APOE ε4) and PRND 3'UTR polymorphism⁸¹ were not considered in this current study.

Furthermore, the measurement instrument employed in this research solely assessed two dimensions of apathy: “reduced social interaction” and “withdrawal from activities of interest (e.g., lack of interest in long-standing activities or socializing with family and friends)” (Morris et al. 2012, p.2)⁴⁰ implying that the behavioral and social domains were adequately assessed while the emotional and cognitive domains of apathy were not accounted for. However, given the lack of a comprehensive apathy measurement instrument, the Apathy Index of the MDS 2.0 serves as a significant initial starting point towards enhancing the recognition of apathy within the Canadian LTCF.

Implications for practice

The findings of this study have several practical implications for improving dementia care in LTCF. First, routine screening for apathy should be integrated into the care plans for newly admitted residents, especially those with identified correlates such as young age, male sex, insomnia, functional decline and severe pain. Second, tailored interventions addressing co-morbidities of apathy in dementia could significantly reduce apathy symptoms. Third, enhancing meaningful engagement through personalized activity programs might serve as a crucial strategy in mitigating apathy and improving overall well-being. Finally, policymakers should consider these findings when developing healthcare policies and allocating resources for dementia care. This may involve funding for the development of more engaging care environments, support for technology-based interventions, and training programs for care staff in early recognition of apathy.

Conclusion

This study provides valuable insights into the prevalence and biopsychosocial characteristics of apathy among newly admitted residents with dementia in Canadian LTCF. The findings emphasize that apathy is more prevalent in younger residents and males, indicating the need for age-specific and sex-sensitive approaches. Biological characteristics such as severe pain and the use of psychotropic medications are strongly associated with apathy, suggesting that effective pain management and careful medication review are crucial. Psychological factors, particularly depression, can also play a significant role in the development of apathy as previously understood, underscoring the importance of addressing depressive symptoms to mitigate apathy. Preferences for social and recreational activities, such as music and exercise, is inversely associated with apathy, highlighting the value of providing meaningful activities for residents. The size and regional location of LTCF also influence apathy prevalence, indicating that facility resources and practices impact resident outcomes.

Taken together, our study calls for routine screening for apathy, effective pain and depression management, enhanced activity engagement, and careful medication management to improve quality of life for residents with dementia. Future longitudinal research is needed to better understand the causative factors of apathy and evaluate the effectiveness of targeted interventions. Ultimately, this current study underscores the need for a holistic and person-centered approach to dementia care that incorporates both pharmacological and non-pharmacological interventions. By recognizing the diverse factors influencing apathy, care staff can better support residents with dementia, enhancing their engagement, well-being, and overall quality of life.

Supplemental Material

sj-docx-1-alz-10.3233_JAD-240370 - Supplemental material for The prevalence and risk factors of apathy among the Canadian long-term care residents with Alzheimer's disease and related dementias

Supplemental material, sj-docx-1-alz-10.3233_JAD-240370 for The prevalence and risk factors of apathy among the Canadian long-term care residents with Alzheimer's disease and related dementias by Aderonke Agboji, Shannon Freeman, Davina Banner, Joshua Armstrong and Melinda Martin-Khan in Journal of Alzheimer's Disease

Footnotes

Acknowledgments

The authors have no acknowledgments to report.

ORCID iDs

Aderonke Agboji

Shannon Freeman

Author contributions

Aderonke Agboji (Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Writing – original draft; Writing – review & editing); Shannon Freeman (Conceptualization; Data curation; Formal analysis; Supervision; Writing – review & editing); Davina Banner (Conceptualization; Writing – review & editing); Joshua Armstrong (Conceptualization; Writing – review & editing); Melinda Martin-Khan (Conceptualization; Writing – review & editing).

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Declaration of conflicting interests

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

Data availability

The data supporting the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy and ethical restrictions.

Supplemental material

Supplemental material for this article is available online.

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