This article is more than 5 years old. Information may no longer be current.

Apathy, depressive symptoms may indicate onset of incident dementia

Apathy and depressive symptoms were independently linked to incident dementia in community-dwelling older adults, and may be an early sign of dementia onset among this population, according to data published in Neurology.

“Little is known about the relation between apathy and dementia in community-dwelling older people,” Jan Willem van Dalen, MSc, from the department of neurology at Academic Medical Center in Amsterdam, and colleagues wrote. “Several studies have linked symptoms of depression in community-dwelling older people to incident dementia. These studies, however, did not differentiate between apathy and depressive symptoms. Distinguishing the two is important since they may be independently and differentially associated with dementia.”

To determine whether apathy and depressive symptoms are independently linked to incident dementia, researchers conducted a prospective observational population-based cohort study with 6-year follow-up among community-dwelling older adults aged 70 to 78 years without dementia at baseline. They used the 15-item Geriatric Depression Scale (GDS-15) to measure apathy and depressive symptoms.

In exploratory analyses, they also examined whether apathy/depressive symptoms were associated with dementia risk in those with normal to high Mini-Mental State Examination (MMSE) scores, whether these symptoms were associated with short-term or long-term development of dementia and whether symptom stability altered their relationship with dementia.

Overall, 232 of 3,427 participants developed dementia. Apathy symptoms showed association with dementia (HR = 1.28; 95% CI, 1.12-1.45; P < .001) and in older adults without depressive symptoms (HR = 1.26; 95% CI, 1.06-1.49; P = .01). After adjusting for age and sex, both apathy symptoms (HR per symptom = 1.23; 95% CI, 1.08-1.4; P = .002) and depressive symptoms (HR = 1.11; 95% CI, 1.04-1.19; P = .002) were linked to heightened risk for dementia. Apathy (HR =1.21; 95% CI, 1.06-1.4; P = .007) and isolated apathy symptoms (HR = 1.2; 95% CI 1-1.45; P = .046) were associated with an increased risk of dementia after additional adjustment for disability, MMSE score and history of cardiovascular disease and stroke. In addition, the associations may be stronger for patients with short-term vs. long-term dementia and also may be attenuated in patients with remitting symptoms. Furthermore, researchers observed a cumulative relation between the number of apathy symptoms and mortality, with a more than twofold increase in mortality risk among participants with high apathy scores.

“Our findings suggest apathy symptoms may be prodromal to dementia and may be useful to consider when trying to identify persons at increased risk,” van Dalen and colleagues wrote. “Clinicians should be watchful of apathy symptoms. Although depression is a relatively well-known risk factor for health deterioration in old age, persons with apathy symptoms without dysphoric symptoms may easily be overlooked, especially since they may tend to withdraw from care.” – by Savannah Demko

Disclosures: The authors report no relevant financial disclosures.