Objective To investigate the association between sleep problems and MCI in a large sample of adults from six low-and middle-income countries (LMICs).
Setting Study on Global Ageing and Adult Health (SAGE).
Subjects 32,715 individuals aged ≥50 years with preservation in functional abilities [age range 50–114 years; 51.7% females].
Methods MCI was defined using the National Institute on Aging-Alzheimer's Association criteria. Sleep problems were assessed by the question “Overall in the last 30 days, how much of a problem did you have with sleeping, such as falling asleep, waking up frequently during the night or waking up too early in the morning?” and categorized as “None”, “Mild”, “Moderate”, “Severe/Extreme”. Multivariable logistic regression analysis and meta-analysis were conducted.
Results Compared to no sleep problems, mild, moderate, and severe/extreme sleep problems were associated with significant 1.40, 1.83, and 2.69 times higher odds for MCI with similar associations being observed between age groups and sex. Severe/extreme sleep problems were positively associated with MCI (i.e., OR > 1) in the six countries studied with the overall estimate being OR = 1.80 (95% CI = 1.50–2.16), and a low level of between-country heterogeneity was observed (I2 = 28.2%).
Conclusions Sleep problems were associated with higher odds for MCI. Interventions to improve sleep quality among middle-aged and older adults in LMICs may be an effective strategy in reducing risk of MCI and dementia.
- Mild cognitive impairment
- Sleep problems
- Low- and middle-income countries
- Middle-aged adults
- Older adults