Anxiety symptoms and mild cognitive impairment among community-dwelling older adults from low- and middle-income countries

Aim: Anxiety may be a risk factor for mild cognitive impairment (MCI) but there is a scarcity of data on this association especially from low- and middle-income countries (LMICs). Thus, we investigated the association between anxiety and MCI among older adults residing in six LMICs (China, Ghana, India, Mexico, Russia, South Africa), and the mediational effect of sleep problems in this association. Methods: Cross-sectional, community-based, nationally representative data from the WHO Study on global AGEing and adult health (SAGE) were analyzed. The definition of MCI was based on the National Institute on Ageing-Alzheimer's Association criteria. Multivariable logistic regression analysis, meta-analysis, and mediation analysis were conducted to assess associations. Results: The final sample included 32,715 individuals aged ≥50 years with preservation in functional abilities [mean (standard deviation) age 62.1 (15.6) years; 48.3% males]. Country-wise analysis showed a positive association between anxiety and MCI in all countries (OR 1.35-14.33). The pooled estimate based on meta-analysis with random effects was OR=2.27 (95%CI=1.35-3.83). Sleep problems explained 41.1% of this association. Conclusions: Older adults with anxiety had higher odds for MCI in LMICs. Future studies should examine whether preventing anxiety or addressing anxiety among individuals with MCI can lead to lower risk for dementia onset in LMICs, while the role of sleep problems in this association should be investigated in detail.