Relationship between psychological distress, health behaviours and future reports of hypertension among adults in East Zimbabwe: a cohort study

INTRODUCTION: Extensive cross-sectional evidence has demonstrated an association between psychological distress (PD) and hypertension. However, evidence on the temporal relationship is limited, especially in low-income and middle-income countries. The role of health risk behaviours including smoking and alcohol consumption in this relationship is also largely unknown. The aim of this study was to investigate the association between PD and later development of hypertension, and how this association may have been influenced by health risk behaviours, among adults in east Zimbabwe. METHODS: The analysis included 742 adults (aged 15–54 years) recruited by the Manicaland general population cohort study, who did not have hypertension at baseline in 2012–2013, and who were followed until 2018-2019. In 2012–2013, PD was measured using the Shona Symptom Questionnaire, a screening tool validated for use in Shona-speaking countries including Zimbabwe (cut-off point: 7). Smoking, alcohol consumption and use of drugs (health risk behaviours) were also self-reported. In 2018-2019, participants reported if they had diagnosed with hypertension by a doctor or nurse. Logistic regression was used to assess the association between PD and hypertension. RESULTS: In 2012, 10.4% of the participants had PD. The odds of new reports of hypertension were 2.04 times greater (95% CI 1.16 to 3.59) among those with PD at baseline, after adjusting for sociodemographic and health risk behaviour variables. Female gender (adjusted odds ratio, AOR 6.89, 95% CI 2.71 to 17.53), older age (AOR 2.67, 95% CI 1.63 to 4.42), and greater wealth (AOR 2.10, 95% CI 1.04 to 4.24 more wealthy, 2.88, 95% CI 1.24 to 6.67 most wealthy) were significant risk factors for hypertension. The AOR for the relationship between PD and hypertension did not differ substantially between models with and without health risk behaviours. CONCLUSION: PD was associated with an increased risk of later reports of hypertension in the Manicaland cohort. Integrating mental health and hypertension services within primary healthcare may reduce the dual burden of these non-communicable diseases.