Focusing on testosterone levels in male: A half-longitudinal study of polycyclic aromatic hydrocarbon exposure and diastolic blood pressure in coke oven workers

Polycyclic aromatic hydrocarbons (PAHs) can interfere with testosterone levels, and low levels of testosterone are associated with increased cardiovascular events. To explore the role of testosterone in PAHs exposure and cardiovascular health, we used data from the 2011-2016 National Health and Nutrition Examination Survey (NHANES) and a longitudinal database of 332 male coke oven workers from China. The urine PAHs, tobacco metabolites and plasma testosterone levels of coke oven workers were measured. There were inverse associations between serum (plasma) testosterone concentrations and the risk of dysarteriotony and dyslipidemia among the NHANES participants and coke oven workers. The results of the cross-lagged panel analysis among workers showed that the decrease in testosterone preceded the increase in diastolic blood pressure (DBP), and the absolute value of the path coefficient from baseline testosterone to follow-up DBP (β2 = -8.162, P = 0.077) was significantly larger than the absolute value of the path coefficient from baseline DBP to follow-up testosterone (β1 = -0.001, P = 0.781). Results from the half-longitudinal mediation analysis showed that baseline hydroxyfluorene predicted significant decreases in plasma testosterone from baseline to follow-up (path a: 0.71, 95% CI: 1.26, -0.16), whereas plasma testosterone at baseline also predicted significant increments in DBP from baseline to follow-up (path b: 9.22, 95% CI: 17.24, -1.19). The indirect effect of PAHs on DBP via plasma testosterone level was marginally significant (test for indirect effects a*b (P = 0.08)). In conclusion, testosterone level is a longitudinal precursor to increased DBP and plays an essential role in the association between PAHs exposure and damage to the cardiovascular system. Coke oven workers with low plasma testosterone levels are more likely to experience adverse changes in blood pressure and lipid levels after exposure to PAHs.