The association between income inequality and adult mental health at the subnational level—a systematic review

Abstract

Purpose A systematic review was undertaken to determine whether research supports: (i) an association between income inequality and adult mental health when measured at the subnational level, and if so, (ii) in a way that supports the Income Inequality Hypothesis (i.e. between higher inequality and poorer mental health) or the Mixed Neighbourhood Hypothesis (higher inequality and better mental health). Methods Systematic searches of PsycINFO, Medline and Web of Science databases were undertaken from database inception to September 2020. Included studies appeared in English-language, peer-reviewed journals and incorporated measure/s of objective income inequality and adult mental illness. Papers were excluded if they focused on highly specialised population samples. Study quality was assessed using a custom-developed tool and data synthesised using the vote-count method. Results Forty-two studies met criteria for inclusion representing nearly eight million participants and more than 110,000 geographical units. Of these, 54.76% supported the Income Inequality Hypothesis and 11.9% supported the Mixed Neighbourhood Hypothesis. This held for highest quality studies and after controlling for absolute deprivation. The results were consistent across mental health conditions, size of geographical units, and held for low/middle and high income countries. Conclusions A number of limitations in the literature were identified, including a lack of appropriate (multi-level) analyses and modelling of relevant confounders (deprivation) in many studies. Nonetheless, the findings suggest that area-level income inequality is associated with poorer mental health, and provides support for the introduction of social, economic and public health policies that ameliorate the deleterious effects of income inequality. Clinical registration number PROSPERO 2020 CRD42020181507.

Predicting self-harm and suicide ideation during the COVID-19 pandemic in Indonesia: A nationwide survey report

“…The pressure as an economic-provider for these unemployed participants might be the reason for this psychological condition, as found in other countries with high unemployment rates (Chen et al, 2021). The self-harm and suicide ideation percentage was also found higher among participants with lower income, which is consistent with a systematic review on the association between economic inequity and poorer mental health, particularly in LMICs (Tibber et al, 2021).…”

“…Therefore, the results might be less relevant to LMICs like Indonesia due to incomparable factors such as socioeconomic, resources, and health infrastructure between the two groups (Pirkis et al, 2021;Tibber et al, 2021;Vijayakumar et al, 2021).…”

A Fresh Evidence of Income Inequality and Health Outcomes Asymmetric Linkages in Emerging Asian Economies

“…This finding is consistent with Qasim et al ( 16 ), who infers that income inequality adversely affects human development in Pakistan. This outcome is not surprising for emerging Asian economies because Tibber et al ( 15 ) found a similar conclusion in a systematic review. In general, we can say that income inequality is not good for the overall health status of nations.…”

“…Accordingly, studies on differences in health conditions amongst persons with diverse socioeconomic positions have exaggerated over the last few decades. Tibber et al ( 15 ) noted that income inequality is negatively associated with mental health and infers that income inequality contributes significantly to mental health problems. While Qasim et al ( 16 ) depicted that income inequality is adversely associated with human development.…”

The effects of U.S. county and state income inequality on self-reported happiness and health are equivalent to zero

“…As another example, an influential literature review used the (disputed) “vote-counting procedure” to conclude that income inequality undermines health [ 23 ], but also neither mentioned the issue of higher-level sample size, nor differentiated small- K from large- K studies (for literature reviews focused on mental health and well-being but having similar shortcomings, see refs. [ 24 , 25 ], respectively).…”