Multimorbidity and perceived stress: a population-based cross-sectional study among older adults across six low- and middle-income countries

Background: Stress in chronic conditions or multimorbidity (>= 2 chronic conditions) has been reported to affect clinical outcomes but there are no studies on the association between stress and chronic conditions/multimorbidity among older adults in low- and middle-income countries (LMICs). Thus, we investigated this association among adults aged >= 50 years across six LMICs. Methods: A cross-sectional analysis using data from the World Health Organization's Study on Global Ageing and Adult Health (China, Ghana, India, Mexico, Russia, South Africa) was conducted. A perceived stress score [range 0 (lowest stress) -100 (highest stress)] was computed based on two questions from the Perceived Stress Scale. Thirteen chronic conditions were assessed. Multivariable linear regression analyses were conducted. Results: 34,129 adults with a mean age of 62.4 (SD = 16.0) years (52.1% females) were included. Overall, 56.6% (95% CI = 55.0%-58.2%) had multimorbidity. In the adjusted model including all countries, compared with those with no chronic conditions, higher numbers of chronic conditions were significantly associated with higher stress levels, dose dependently. In a countrywide meta-analysis, multimorbidity was associated with significantly higher stress levels in all countries (especially India and Ghana) although characterized by moderate heterogeneity (r(2) = 54.6%). For single chronic conditions, notably high stress scores were observed for depression, stroke, and hearing problems. Conclusion: Chronic conditions and multimorbidity are associated with higher levels of stress in older adults in LMICs. Given that perceived stress and chronic conditions are collectively associated with worse health outcomes, low-cost, population-level integrated interventions to address stress among those with chronic conditions are urgently needed.