Urbanicity, Social Capital, and Depression in Older Adults: An Analysis of Two African Countries

Depression is a significant contributor to global morbidity and mortality and is the primary cause of disability worldwide. Older adults are an age group that may be more vulnerable to depression due to a higher prevalence of many known risk factors. Moreover, evidence also suggests that living in urban locations can increase the risk of depression and other mental illnesses. Thus, as the world’s population continues to age and urbanize, the burden of depression could increase. However, very few studies on the links between urbanicity and depression in older adults have been conducted in low- and middle-income settings such as sub-Saharan Africa, despite its rapid urbanization and substantial increases in the size of its aging population. Through quantitative analyses of secondary data from the Ghana and South Africa samples of the World Health Organization (WHO) Study on Global AGEing and Adult Health (SAGE), this dissertation therefore sought to explore the relationship between urbanicity and depression among older adults in an African context. The study specifically used multivariable logistic regression to examine the association between current urban residence and depression in Ghanaian and South African older adults as well as whether urbanicity of residence across the life course was associated with depression in these populations. It also assessed the influence of urbanicity on the relationship between depression and social capital—a purported protective factor—through structural equation modeling. Results indicated that there was no significant association between urbanicity and depression based on current residence or life-course residence in either country. Additionally, urbanicity did not substantially modify the effects of social capital on depression in either nation, but urban-rural differences in the level and composition of social capital were observed. Moreover, while trust was associated with a lower risk of depression in South Africa overall, sociability and trust were associated with an increased risk of depression in Ghana. These findings provide some insight into the socio-contextual determinants of depression in Ghanaian and South African older adults and may help to inform decisions on the allocation of mental health resources as well as policies and interventions to address later-life depression in these populations

Assessing urban-rural differences in the relationship between social capital and depression among Ghanaian and South African older adults.

IntroductionResearch has demonstrated benefits of social capital on depression, but variations in this relationship by geographic characteristics such as urbanicity have rarely been investigated.MethodsUsing survey data on 4,209 Ghanaian and 3,148 South African adults aged 50 and above from the World Health Organization (WHO) Study on Global AGEing and Adult Health (SAGE), exploratory and confirmatory factor analyses were conducted to extract dimensions of social capital from survey items. Structural equation models with the extracted factors were then used to estimate the associations between social capital and depression in each sample and assess differences between urban and rural settings with measurement and structural invariance tests.ResultsFactor analyses suggested three dimensions of social capital representing community engagement, sociability, and trust. Urbanicity did not substantially modify the effects of social capital on depression in either setting, but urban-rural differences in the measurement and level of social capital were observed. Urban Ghanaian older adults were less socially integrated and trusting than older rural residents (standardized mean difference: -0.28, -0.24, and -0.38 for community engagement, sociability, and trust, respectively) while urban South African older adults appeared less engaged in community activities but significantly more trusting and socially active informally than older rural residents (standardized mean difference: -0.33, 0.30, and 0.17 for community engagement, sociability, and trust, respectively). Moreover, while trust was associated with a lower risk of depression in South Africa overall, sociability and trust were associated with an increased risk of depression in Ghana.ConclusionsResults indicate that the composition and average levels of social capital differ between urban and rural older adult residents in Ghana and South Africa although urban-rural differences in the strength of the association between social capital and depression were not substantial. Furthermore, the associations between social capital and depression are context-specific and are not uniformly beneficial