Cardiovascular risk factors and kidney function among automobile mechanic and their association with serum heavy metals in Southwest Nigeria: A cross-sectional study

INTRODUCTION: The burden of cardiovascular disease (CVD) is huge due to its associated morbidity, mortality and adverse socio-economic impact. Environmental pollution as a risk factor contributes significantly to the burden of CVD, especially in the low and middle income countries. One of the effective strategies to reduce CVD burden is to prevent or detect cardiovascular risk factors early in at-risk population. This study determined some cardiovascular risk factors, kidney function, and their association with heavy metals among automobile mechanics. METHOD: This was a cross-sectional study involving 162 automobile mechanics and 81 age and sex matched controls. Serum levels of lead, cadmium and some cardiovascular risks were assessed and compared in the two groups. Associations between serum lead, cadmium and some cardiovascular risks were determined using correlation analysis. P value of <0.05 was taken as significant. RESULTS: The mean ages of the automobile mechanics and controls were 47.27±9.99 years and 48.94±10.34 years, respectively. The prevalence of elevated serum cadmium was significantly higher in the automobile mechanics (25.9% vs 7.9%; p = <0.001). The significant cardiovascular risk factors in the automobile mechanics vs controls were elevated total cholesterol (32.1% vs 18.5%; p = 0.017), hyperuricemia (20.4% vs 1.2%; p = <0.001), elevated blood glucose (16.0% vs 4.9% p = 0.013); and alcohol use (55.1% vs 30.0%; p = 0.001). Among the automobile mechanics, there were significant positive correlations between serum cadmium, atherogenic index of plasma (AIP) (p = 0.024; r = 0.382) and triglyceride (p = 0.020; r = 0.391). Significant positive correlation was found between serum lead and neutrophil gelatinase associated lipocalin (NGAL) (p = <0.001; r = 0.329). There were significant positive correlation between serum cadmium level, AIP (p = 0.016; r = 0.373) and TG (p = 0.004; r = 0.439); between serum lead and NGAL in all the study participants (p = 0.005; r = 0.206). CONCLUSION: Automobile mechanics have notable exposure to heavy metals and a higher prevalence of some cardiovascular risk factors. Health education and sensitisation as well as policies that would regulate exposure of persons to heavy metals should be implemented in Nigeria.