Life-course socioeconomic position and cardiovascular diseases among older adults in low- and middle-income countries: A systematic review

BACKGROUND: In low- and middle-income countries (LMICs), economic instabilities may alter people's socioeconomic position (SEP) throughout their life course affecting their health. We conducted a systematic review to identify which life-course models link SEP over the lifespan and cardiovascular diseases (CVD) among older adults in LMICs. METHODS: Four databases were searched (PUBMED, EMBASE, SocINDEX, PsycInfo), yielding 3097 English articles after removing duplicates. Studies were graded using the Newcastle-Ottawa Quality Assessment Scale and results were reported through narrative synthesis and by life-course model. RESULTS: After screening the abstracts, 32 studies were included. After screening and grading the full text articles, six studies were included (four cross-sectional and two cohorts). Although the review aimed to capture evidence from LMICs, all eligible studies identified were conducted in middle-income countries. The results were reported based on the number of analyses conducted across six studies, which together included eleven countries. Results showed that three analyses supported the critical period model, two supported the accumulation model, while the remaining analyses did not support any of the life-course models. The social mobility model was not analyzed in any of the studies. Furthermore, our review showed inconsistent associations in both the critical period and the accumulation models. Some studies indicated that low childhood or adulthood SEP was associated with higher risk of CVD, while others reported lower risk. CONCLUSIONS: Findings varied across studies, with some evidence consistent with both the critical period and accumulation models, although relatively few studies examined the latter. No studies evaluated the social mobility model. Further longitudinal research, particularly in low-income countries, is needed to better understand life-course socioeconomic influences on CVD.