ABSTRACT Purpose: Many experiences in late-life may contribute to depression, but some older adults appear more vulnerable than others. We investigated the association of resilience, apathy, age and disability with late-life depression. Methods: Within an ongoing cohort study, we collected data on depression (Geriatric Depression Scale 15-item (GDS)), disability (NHIS 16 item scale), resilience (Hardy & Gill Resilience Scale), and apathy (Starkstein Apathy Scale). Resilience is an innate ability to remain well in the face of adversity. Apathy is a decrease in motivation and goal-related thought content and behavior. This sub-study uses cross sectional data and multiple regression analysis. Results: Subjects (n=114, mean age 80.3, 82.7% Caucasian, 81.8% female, 49.1% living alone) had a mean (SD) GDS score of 3.3 (3.4) and mean (SD) NHIS disability score of 12.0 (2.9). The group had moderate degrees of resilience (mean (SD) resilience score 9.6 (4.6), and moderate apathy

ABSTRACT (mean (SD) apathy score 13.5 (5.9)). Overall, independent functioning (β=-0.29; p=0.0023) and resilience (β=-0.28; p<0.0001) were associated with a lesser number of depressive symptoms, while apathy (β=0.25; p<0.0001) was associated with a greater number of depressive symptoms. Resilience explained most variability (18%) in the young-old (<80), while apathy explained the most variability (24%) in the old-old (80+). Conclusions: Within a sample of community-dwelling elders, resilience, apathy and level of disability appear to be associated with the number of depressive symptoms. Resilience plays the greatest role in the young-old (< 80), whereas apathy appears to be a more significant factor in the old-old. Apathy in the old-old, which may represent either organic brain disease or a general disengagement from society, is associated with depressed mood. Our findings suggest that age-related developmental factors may be correlated with late-life depression.

Introduction Late-life depression is a common occurrence in medically ill elderly Aging often involves increasing levels of physical disability and frailty, which may influence the development of late-life depression Risk factors for late-life depression may include how elders approach these age-related changes. Risk factors can include resilience, apathy, age.

Hypothesis Disability Depression (IADL/ADL) (GDS) Age Apathy: decrease in overt behavior and goal-directed thought content, along with shallow or unchanging emotion Resilience: the capacity to remain well, recover, or even thrive in the face of adversity.

Methods 159 community-dwelling older adults Parent Study: 159 community-dwelling older adults Recruited from 13 geriatric practices in the Pittsburgh area Participating in an 18 month study on frailty Interviewed in their homes at baseline, 6 mo, 12 mo, & 18 mo Cross-sectional sub-study: 114 subjects consented to our additional IRB approved assessments 31 subjects did not participate in this sub-study [1 lost to follow-up, 9 died, 15 changed PCP, 3 missed study appointment, 3 withdrew consent]

Methods - Subjects Inclusion Criteria: Age: 65 years or older Sex: Male or Female Short Physical Performance Battery (SPPB): 3-10, mild-moderate physical impairment Community Dwelling MMSE > 24 at baseline Exclusion Criteria: Known terminal condition Diagnosis of progressive dementing condition

Methods - Assessment Depression (dependent): 15-item Geriatric Depression Scale Physical Disability (independent): NHIS Activities of Daily Living scale (ADL & IADL). Resilience: Hardy & Gill et al. (JAGS, 2004) Apathy: Starkstein et al. (J Neuropsychiatry, 1992) Statistical Analysis: Linear Regression Models

Results – Demographics/Health Status Mean (SD) Range AGE (years, n = 110) 80.3 (7.0) 67-99 RACE (% Caucasian) 82.7% GENDER (% Female) 81.8% LIVING ALONE 49.1% MMSE 27.6 (2.1) 21-30 GDS (n = 110) 3.3 (3.4) 0-14 GDS > 5 24.8% ADL/IADL Score 12.0 (2.9) 3-16 Resilience (n = 104) 9.6 (4.6) 1-17 Resilience (% > 10) 46.9% Apathy Scale (n = 109) 13.5 (5.9) 3-29 Apathy Scale (% > 14) 48.1%

Results – all subjects (n=99) Depression (GDS) R2 = 0.47 Resilience Apathy β = 0.25 P < 0.0001 Partial R2 = 16% β = -0.28 P < 0.0001 Partial R2 = 13% IADL/ADL β = -0.29 P = 0.0023 Partial R2 = 6% β = the estimated change in the number of depressive symptoms corresponding to an additional increase of 1 point in disability, apathy and resilience scales.   Partial R2 = The proportions of variability explained by each factor

Results - Age Group: < 80 years (n=47) Depression (GDS) R2 = 0.52 Resilience Apathy β = -0.37 P = 0.0002 Partial R2 = 18% β = 0.21 P = 0.0027 Partial R2 = 11% IADL/ADL β = -0.35 P = 0.0128 Partial R2 = 8% β = the estimated change in the number of depressive symptoms corresponding to an additional increase of 1 point in disability, apathy and resilience scales.   Partial R2 = The proportions of variability explained by each factor

Results - Age Group: 80+ years (n=52) Depression (GDS) R2 = 0.45 Resilience Apathy β = -0.18 P = 0.0194 Partial R2 = 7% IADL/ADL β = 0.31 P < 0.0001 Partial R2 = 24% β = -0.20 P = 0.0995 Partial R2 = 3% β = the estimated change in the number of depressive symptoms corresponding to an additional increase of 1 point in disability, apathy and resilience scales.   Partial R2 = The proportions of variability explained by each factor

Conclusions Within a sample of community-dwelling elders, resilience, apathy and level of disability are associated with depressive symptoms. High levels of resilience are associated with fewer depressive symptom. High levels of disability and apathy are both associated with more depressive symptoms. Resilience appears to play a greater role in the young-old (< 80), whereas apathy appears to be a more significant factor in the old-old (80+).

Limitations & Strengths Small number of subjects (n = 114) Majority of subjects were females Selection Bias (e.g., who joins research studies) ___________________________________________________________________________ Community sample Well characterized in terms of health status and function Unique approach to conceptualizing depression via measurement of resilience and apathy.

Future Directions Additional studies are needed… to examine the role of age-related developmental factors in maintenance of mental health in the face of stressful events, and to better understand successful coping mechanisms for older adults.

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