Inequalities in common mental health disorders: understanding the predictors of lifetime prevalence, treatment utilisation, and helpfulness across 113 countries

Socioeconomic inequalities in common mental health disorders (CMDs) cut across each step in the cascade of care: less affluent individuals have a higher lifetime prevalence of CMDs, are less likely to utilise treatment, and less likely to perceive the treatment as helpful when they do receive it. Here, I test whether such socioeconomic inequalities exist globally across 113 countries and, additionally, which psychological and country-level factors are associated with the three health outcomes (ie, CMD prevalence, treatment utilisation, and helpfulness).This study uses cross-sectional survey data from the Wellcome Global Monitor 2020 (n=119 088 from 113 countries) to test whether individual-level socioeconomic factors, individual-level psychological factors (stigma and trust), and country-level factors (GDP, GINI, and health expenditure) predict CMD lifetime prevalence, utilisation, and perceived helpfulness of talking to a mental health professional and taking prescribed medication. Multi-level logistic regression models were used, which included the three types of predictors (socioeconomic, psychological, and country-level factors) and controlled for age and gender.Individuals with higher household income are less likely to experience anxiety or depression (odds ratio [OR] 0·90 for each income quintile [95% CI 0·89-0·91]), more likely to talk to a mental health professional (1·05 [1·03-1·07]; 1·34 [1·22-1·46] for higher education), and more likely rate this treatment as very helpful (1·06 [1·03-1·10]) across countries. By contrast, income is not linked with utilisation (OR 0·99 [95% CI 0·97-1·01]) and helpfulness of taking prescribed medication for CMDs (1·02 [0·99-1·05]). Among the psychological predictors, stigma reduces utilisation (OR 0·95 [95 CI 0·92-0·99]) and helpfulness of talking therapy (0·77 [0·72-0·81]), whereas trust in health practitioners increases both (OR 1·07 [95% CI 1·04-1·10] for utilisation and 1·31 [1·24-1·39] for helpfulness). Country-level health expenditure is related to higher treatment utilisation (OR 1·11 [95% CI 1·04-1·18]), but not perceived treatment helpfulness (1·03 [0·97-1·09]).Across 113 countries, socioeconomic inequalities in the three mental health outcomes deepen disadvantages for less affluent individuals along the cascade of care. For pharmacological treatment, however, socioeconomic factors are not associated with treatment utilisation and helpfulness. Finally, psychological factors as well as structural country-level factors also determine utilisation and helpfulness.Economic and Social Research Council.