Association between rural-to-urban migration and the onset of hypertension among middle-aged and older population: evidence from India.

Background: Rural-to-urban migration is a key contributor to urbanization in India and has potential implications for hypertension risk. Amidst the rising elderly population, the inequal burden of hypertension between migrants and non-migrants remains largely underexplored. This study examines the association between rural-to-urban migration and hypertension onset, focusing on rural-born individuals who have migrated to urban areas compared to those who have remained lifelong residents of rural areas.

Methods: Data from 27,270 participants aged 45 and above from the Longitudinal Ageing Study in India were analysed, including 18,855 non-migrant rural residents and 8,415 rural-to-urban migrants. The onset of hypertension was evaluated using bivariate statistics and the Cox proportional hazards model.

Results: Approximately 20% of rural non-migrants and 38% of rural-to-urban migrants were hypertensive. The median age of hypertension onset was 57 years for non-migrants and 54 years for migrants. Overall, migrants had a 1.22-fold (95% CI: 1.11-1.34) higher risk of hypertension onset. Regionally, migrants in the Northern (HR: 1.30, 95% CI: 1.10-1.53), Eastern (HR: 1.19, 95% CI: 0.99-1.44), and Southern regions (HR: 1.23, 95% CI: 1.07-1.43) were at a significantly higher risk of hypertension onset than their non-migrant peers.

Conclusion: These findings suggest that rural-to-urban migration may contribute to the early onset of hypertension in India, with notable variations across regions.