Examining Differences between Homebound Older Adult Pet Owners and Non-pet Owners in Depression, Systemic Inflammation, and Executive Function

Abstract

ABSTRACTHomebound older adults are prone to depression, which is linked to systemic inflammation that promotes executive function decline. A companion animal may reduce the negative biobehavioral processes asso- ciated with depression, inflammation, and reduced executive function in homebound older adults. The primary aim of this study was to examine dif- ferences between homebound older adult pet owners and non-pet owners in depression, salivary C-reactive protein (CRP), and executive function. The secondary aim was to determine if the level of attachment to pets was as- sociated with depression, salivary CRP, and executive function. The study was cross-sectional and investigated homebound older adult pet owners and non-pet owners (n = 88) using psychometrically reliable and valid instru- ments (Geriatric Depression Scale Short Form and CLOX 1). Salivary CRP was assessed with immunoassay. Level of attachment to pets was measured using a Likert scale (0–10). Mean age for the total sample was 75 years (SD = 9). Forty-eight (55%) participants owned pets (56% dogs, 25% cats, 4% other pets, 15% both cats and dogs). Pet owners reported a high level of attachment to pets (Median = 10). Pet owners had significantly higher ex- ecutive function than non-pet owners (t = –2.07; p = 0.04) but there were no significant differences in executive function between cat owners and dog owners (t = 1.53; p = 0.14). Pet owners and non-pet owners were similar in depression (t = –1.80, p = 0.08) and salivary CRP levels (t = 0.27, p = 0.79). Level of attachment to pets was significantly and positively correlated with executive function (r = 0.30; p = 0.04) but was not significantly correlated with depression (r = 0.04, p = 0.77) or salivary CRP (r = –0.04, p = 0.80). Compared with non-pet owners, pet owners had better executive function but similar depression and salivary CRP levels. Reasons for these findings are unclear. Significant positive correlation be- tween pet attachment and executive function suggests further investigation in this area. Future studies with larger samples and a longitudinal design are needed to investigate the biobehavioral changes over time in relation to pet ownership, level of attachment to pets, and executive func- tion in homebound older adults.