Association between Passive Smoking and Hypertension: A Panel Study with 621.506 Adults from Brazil

Abstract Background Passive smoking, which affects a large number of people, may create a predisposition to cardiovascular disease in a manner similar to active smoking. However, this relationship is poorly explored in the scientific literature. Objectives This study aimed to investigate the association between passive smoking and hypertension in an adult population in Brazil. Methods This panel study utilized data on the Brazilian population collected through a VIGITEL survey conducted between 2009 and 2021. The data were analyzed using Poisson regression with a 95% confidence interval (95%CI). Results The prevalence of hypertension in our population was 24.9% (95%CI 24.6-25.1), and passive smoking was observed in 16.3% (95%CI 16.0-16.5). The adjusted analysis revealed that passive smoking leads to a high risk of hypertension (PR=1.10; 95%CI 1.07 to 1.14), which was surprisingly close to the risk among heavy smokers (>1 pack or 20 cigarettes a day) (PR 1.09; 95%CI 1.06 to 1.13). Another noteworthy finding was the higher prevalence of hypertension among former smokers, highlighting associations that are poorly explained in the literature. Conclusion A significant association was found between passive smoking and hypertension, demonstrating that passive smokers are as prone to developing hypertension as heavy smokers. Therefore, we recommend a meta-analysis to consolidate the evidence on this subject and strengthen our findings.