Apathy and depressive symptoms are independently associated with incident dementia in community-dwelling older people, according to a study published in Neurology.
The research team, led by Jan Willem van Dalen, from the Department of Neurology at the Academic Medical Center in Amsterdam, assessed whether apathy and depressive symptoms are independently associated with incident dementia during a 6-year follow-up in a prospective observational population-based cohort study. Participants were community-dwelling people, aged 70 to 78 years, in the Prevention of Dementia by Intensive Vascular Care trial, without dementia at baseline. Apathy and depressive symptoms were measured using the 15-item Geriatric Depression Scale (GDS-15).
Dementia was defined as a clinical diagnosis according to DSM-IV criteria. Diagnoses of dementia were re-evaluated after 1 year of additional follow-up to avoid false-positive diagnoses. As a secondary end point, cognitive decline was the change in MMSE score during the study compared to baseline.
Of the 3,526 participants, 27 (0.7%) were excluded due to missing apathy or depression scores. At baseline, 693 participants (19.8%) had ≥2 apathy symptoms, 656 (18.7%) had ≥2 depression symptoms, and 322 (9.2%) concurrently had ≥2 apathy and ≥2 depression symptoms. Follow-up regarding dementia was complete for 3,427/3,499 (98%) participants: 232/3,427 (6.8%) were diagnosed with dementia a median of 60 months after baseline. In total, 577/3,492 (16.5%) participants died during follow-up after a median of 54 months.
After adjustment for age and sex, apathy symptoms (hazard ration [HR], 1.23) and depressive symptoms (HR, 1.11) were associated with an increased risk of dementia. Associations were similar for isolated apathy (HR, 1.20) and depressive symptoms (HR, 1.15). After additional adjustment for disability, MMSE score, history of cardiovascular disease (CVD), and history of stroke, only apathy (HR, 1.21) and isolated apathy symptoms (HR, 1.20) were associated with an increased risk of dementia.
“Our results suggest symptoms of apathy are associated with incident dementia in community-dwelling older people without cognitive impairment,” stated the authors. “This association is independent of depressive symptoms, age, sex, MMSE score, disability, and history of CVD or stroke. Depressive symptoms were also associated with dementia independent of age and sex but no longer when the symptom of subjective memory complaints was left out.”
van Dalen JW, Van Wanrooij LL, Moll van Charante EP, Richard E, van Gool WA. Apathy is associated with incident dementia in community-dwelling older people. Neurology. 2018 Jan 2;90(1). doi: 10.1212/WNL.0000000000004767