Apathy is associated with an increased risk for incident dementia in patients with mild cognitive impairment (MCI) and isolated subjective cognitive concerns, according to research published in JAMA Psychiatry. Researchers noted that, “Apathy deserves more attention as a relevant, cheap, noninvasive, and easily measurable marker of increased risk [for] incident dementia with high clinical relevance, particularly because these vulnerable patients may forgo health care.”
Researchers assessed 16 studies available through Medline, Embase, and PsychINFO databases in a systematic review and quantitative synthesis of evidence of an association between apathy in dementia-free older individuals and incident dementia. The studies included populations with subjective cognitive concerns, MCI, cognitive impairment with no dementia, and mixed cognitive impairment and no cognitive impairment. Apathy status was available for 7299 participants and apathy was present in 1470 (20.1%) participants.
The limitations included potential publication bias, significant attrition, the fact that odds ratios and risk ratios may give distorted results, and that the value of subgroup analyses is limited by small subgroups easily dominated by single studies.
Researchers found that the combined risk ratio for dementia in patients with apathy was 1.81, the hazard ratio was 2.39, and the odds ratio was 17.14. Apathy was associated with a 2-fold increase in the risk for dementia among memory clinic patients. Subgroup analyses, meta-regression, and individual study results suggested the association between apathy and dementia weakens with increased follow-up time, age, and cognitive impairment. Adjusting for apathy definition and follow-up time explained 95% of heterogeneity in MCI.
These findings have high clinical relevance because patients with apathy are likely to withdraw from care. The risk for dementia among patients with apathy appears to be independent of concurrent depression, greater in the short term, and less strong with higher age and greater cognitive impairment. Apathy may be a powerful marker of increased risk for incident dementia.
van Dalen JW, van Wanrooij LL, van Charante EPM, Brayne C, van Gool WA, Richard E. Association of apathy with risk of incident dementia: a systematic review and meta-analysis [published online July 18, 2018]. JAMA Psychiatry. doi:10.1001/jamapsychiatry.2018.1877