Are the Tribal Highlanders Protected from Hypertension? A Meta-Analysis on Prevalence of Hypertension among High Altitude Tribal Population of India

Background: The so-called protected tribal population are also facing burden of noncommunicable diseases. The high altitude tribes are thought to be genetically and environmentally protected from hypertension (HTN) like diseases. Objective: The objective is to estimate the prevalence of HTN among tribes residing at high altitudes (>6000 feet above sea level) of India. Methods: The meta-analysis was undertaken during March to August 2018. National Library of Medicine's PubMed database, and Google scholar were comprehensively searched including search terms such as "blood pressure, hypertension and prevalence" combined with "tribal, tribes, high altitude, India." Articles on the prevalence of HTN were searched first and then were segregated on the basis of high altitude (>6000 ft). Results: Initially, 69 references and a total of 16 abstracts were screened. After applying the inclusion and exclusion criteria on 16, eight studies were included. Meta-analysis of the prevalence of selected studies resulted in a pooled estimate mean prevalence of HTN among tribal population to be 11.43% (95% confidence interval: 6.72%-17.21%). Conclusion: The role of epidemiological transition needs to be read in the context of social anthropology to identify factors preventing HTN among high altitude tribes.