Can loss of interest be sign of dementia risk? Study says people with severe apathy 80% more likely to get it
Older adults with severe apathy, or lack of interest in usual activities, may have a greater chance of developing dementia than people with few symptoms of apathy, according to researchers. After adjusting for age, education, cardiovascular risk factors and other factors that could affect dementia risk, they found that people with severe apathy were 80% more likely to develop dementia than people with low apathy.
“While depression has been studied more extensively as a predictor of dementia, our study adds to the research showing that apathy also deserves attention as an independent predictor of the disease. In fact, we believe that apathy may be a very early sign of dementia and it can be evaluated with a brief questionnaire,” says study author, Dr Meredith Bock, University of California, San Francisco. Dementia is the loss of cognitive functioning — thinking, remembering, and reasoning — and behavioral abilities to such an extent that it interferes with a person’s daily life and activities. According to the US Centers for Disease Control and Prevention (CDC), of those at least 65 years of age, there was an estimated 5 million adults with dementia in 2014 and the number is projected to be nearly 14 million by 2060.
The current analysis involved 2,018 adults with an average age of 74. None had dementia. At the start of the study, the team measured apathy using a survey with questions such as: “In the past four weeks, how often have you been interested in leaving your home and going out?” and “In the past 4 weeks, how often have you been interested in doing your usual activities?” Participants were then divided into three groups: those with low, moderate, and severe apathy. After nine years, the investigators determined who had dementia by looking at medication use, hospital records, and results on cognitive tests.
The analysis reveals that there were 768 (38%) participants in the low apathy group, 742 (37%) participants in the moderate apathy group, and 508 (25%) participants in the severe apathy group. Participants with greater apathy at baseline were significantly more likely to be male, black and less educated. They were also more likely to have a higher BMI and report a history of cigarette smoking. There were 255 participants in the cohort that met the criteria for clinically depressed mood. Half of these individuals (126 out of 255) reported symptoms of severe apathy, compared to 33% (85 out of 255) that reported moderate apathy and 17% (44 out of 255) that reported low apathy.
Severe apathy was associated with an increased risk of dementia compared to low apathy. By the end of the study, 381 participants, or almost 19%, developed dementia. In the low apathy group, 111 out of 768 people or 14% developed dementia, compared to 143 out of 742 people or 19% in the moderate apathy group. In the severe apathy group, 127 out of 508 people or 25% developed dementia. Greater apathy was also associated with worse cognitive score at the beginning of the study, but not the rate of change over time.
“In a diverse cohort of community-dwelling adults, apathy was associated with an increased risk of developing probable dementia. We found that community-dwelling older adults who report greater symptoms of apathy are approximately 80% more likely to develop probable dementia compared to those with few symptoms. This study provides novel evidence for apathy as a prodrome of dementia,” reveal findings published in Neurology, the medical journal of the American Academy of Neurology.
According to Dr Block, apathy can be very distressing for family members, when people no longer want to get together with family or friends or do not seem interested in what they used to enjoy. “More research is needed, but it's possible that these are signs that people may be at risk for Alzheimer’s disease and could benefit from early interventions and efforts to reduce other risk factors,” suggests Dr Block.