Background: Mine workers face various health risks from occupational hazards, notably dust-related pulmonary dysfunction. This dysfunction is also attributed to diverse risk factors and health conditions. Despite the variety of underlying mechanisms, conflicting evidence persists regarding hypertension as a potential risk factor for such dysfunction.
Objective: To determine the predictors of pulmonary dysfunction vis-à-vis the hypertension status of mine workers.
Methods: We conducted a cross-sectional study among 444 mine workers from ten open-cast mines in Gujarat state (western part of India) from November 2020 to February 2022. We collected data on demographics, occupation, addiction, and comorbidities, including measurements like anthropometry, blood pressure, blood sugar, haemoglobin, and lipid levels. Hypertension was confirmed based on self-reported history and/or onsite blood pressure measurement, while pulmonary functions were assessed using a spirometer (expressed as forced expiratory volume in the first second FEV1 and forced vital capacity FVC). Multiple linear regression analysis was performed to determine the significant predictor of FEV1 or FVC vis-à-vis the hypertension status after adjusting for confounding variables. In addition, we assessed the effect of anti-hypertensive medications on pulmonary dysfunction.
Results: A total of 41% (95% CI: 36-45%) of mine workers were suffering from hypertension. On multiple linear regression, only being a male and work experience duration were the significant predictors of FEV1 [0.900 (0.475-1.092), p=<0.001; -0.029 (-0.034 - -0.021, p=<0.001] and FVC [1.088 (0.771-1.404), p=<0.001; -0.031 (-0.038 - -0.024, p = 0.001] respectively. While unadjusted analysis indicated hypertension led to FEV1 and FVC reduction, this effect lost significance after adjusting for confounders. Nevertheless, subgroup analysis revealed those on antihypertensive medications had reductions in FEV1 and FVC by -0.263 (95% CI: -0.449 - -0.078, p = 0.006) L and -0.271 (95% CI: -0.476 - -0.067, p = 0.009) L respectively.
Conclusion: In our study among mine workers, alterations in lung function (FEV1 and FVC) on spirometry were predicted by gender and duration of work experience, while hypertension did not serve as a predictor. It is noteworthy that antihypertensive drugs were found to reduce lung functions on spirometry, highlighting the need for further research.
Keywords: Blood pressure; India; antihypertensive agents; cross-sectional studies; miners; spirometry.