Among older adult patients in memory clinics, apathy was linked with an almost doubled risk for incident dementia, according to findings published in JAMA Psychiatry.
“Apathy has been associated with incident dementia and could be useful as an easily assessable, low-cost, noninvasive marker of increased risk, which is relatively common and specific for future cognitive decline compared with other neuropsychiatric symptoms,” Jan Willem van Dalen, MPhil, from the department of neurology, University of Amsterdam, and colleagues wrote. “However, evidence is fragmented, and apathy definitions vary greatly between studies.”
Researchers performed a systematic review of clinical databases and meta-analysis of relvant evidence to determine the link between apathy in dementia-free older adults and incident dementia in longitudinal studies. Prospective cohort studies that included general populations or memory clinic patients without dementia, had clear definitions of apathy and dementia, and reported on the relationship between apathy and incident dementia were included in this analysis.
In total, 16 studies comprising 7,299 participants with available apathy data met inclusion criteria. Two studies included patients with subjective cognitive concerns, 11 included patients with mild cognitive impairment, one included patients with cognitive impairment but no dementia and two included patients with mixed cognitive and no cognitive impairment. Follow-up was up to 5.4 years.
The results showed that apathy was consistently tied to an increased risk for incident dementia in patients with mild cognitive impairment and subjective cognitive concerns; however, heterogeneity was considerable.
Of 7,299 participants, apathy was present in 20% of 7,299 (n = 1,470). In the studies that used the validated definition of apathy, the overall risk ratio for developing dementia for patients with apathy was 1.81 (95% CI, 1.32-2.5) and the heterogeneity was high (I2 = 76%). The combined hazard ratio was 2.39 (95% CI, 1.27-4.51), with considerable heterogeneity (I2 = 90%). The overall OR estimate was 4.6 (95% CI, 0.26-80.2; I2 = 89%), with estimates ranging from 1.48 to 17.14 (95% CI, 1.91-153.98; I2 = 60%).
Results from further analyses suggest that the relationship between apathy and dementia weakened with increasing follow-up time, age and cognitive impairment.
“Results suggest apathy in older people deserves more attention as a prognostic factor,” Willem van Dalen and colleagues wrote.
“While much research is aimed at prognostic biomarkers based on advanced [MRI] techniques or cerebrospinal fluid analyses, relatively simple measurement of neuropsychiatric symptoms merits consideration because it is less invasive, cheaper and easier to implement on a broad scale,” they continued. “For population and health care systems under financial constraint, taking apathy as a marker should be explored as a possible alternative to invasive and relatively expensive investigations.” – by Savannah Demko
Disclosure: The authors report no relevant financial disclosures.