The Positive Effects of Pet Ownership on Alzheimer's Disease

Human-animal interactions are known to have many beneficial psychosocial and psychophysiological effects on persons with and without medical health conditions. There are no previous prospective studies with long follow-up times on the effects of domestic pets on the persons with Alzheimer's disease (AD) living at home.

To investigate the effects of pets on the activities of daily living (ADL), disease progression, and neuropsychiatric symptoms (NPS) during a five-year follow-up on the persons with AD.

Altogether 223 home-dwelling persons (mean age 75.2 years) with very mild (CDR 0.5) or mild (CDR 1) AD at baseline were included for this study. ADCS-ADL, NPI, MMSE, and CDR-SOB were measured at baseline, annually for three years and after five years.

Totally 40 (17.9%) participants had a pet. At the baseline, pet owners and non-pet owners had no significant differences in age, gender, or the ADCS-ADL, NPS, and CDR-SOB scores, while MMSE was lower in pet owners than non-pet owners (20.2 versus 21.7; p = 0.009). Over the follow-up, pet owners had significantly better mean ADCS-ADL (57.5 versus 54.0; p = 0.031), NPI (9.3 versus 13.0; p = 0.038), and CDR-SOB scores (5.7 versus 6.6; p = 0.004) compared to non-pet owners. The differences in the MMSE scores between the groups detected at baseline attenuated over time.

Significant positive effects of the pets on ADL functions, NPS, and disease progression were detected over the whole follow-up suggesting that having a pet may support daily activity and slow the disease progression in AD.