RESUMO
Background: The African Copperbelt is a site of intense artisanal and industrial mining and refining of copper and cobalt. Aim: We aimed to investigate factors that are possibly associated with erectile dysfunction (ED) in metal miners in the former Katanga province of the Democratic Republic of the Congo. Methods: In a cross-sectional study of 138 miners and 139 controls (bakers), we administered questionnaires to obtain sociodemographic and occupational data and to assess male sexual function (International Index of Erectile Function [IIEF]) and marital relation quality (Revised Dyadic Adjustment Scale). Furthermore, we measured trace metals in blood and urine, as well as testosterone and thyroid hormones in serum. Outcomes: Outcomes included the prevalence of questionnaire-derived ED and the relation of ED with individual characteristics, serum testosterone, and environmental factors. Results: Miners were on average 4 years older than bakers (mean ± SD, 37.5 ± 6.9 vs 33.3 ± 5.7 years). Miners had significantly lower scores than bakers on the IIEF (median [IQR], 66 [49-73] vs 73 [66-74]) and the 3 domains of the Revised Dyadic Adjustment Scale (consensus, satisfaction, cohesion). Free testosterone was significantly lower in miners than bakers (ng/dL; 8.11 [6.90-10.10] vs 10.52 [8.83-12.58]; P Ë .001). In miners, sex hormone-binding globulin correlated positively with blood Pb and urinary Cd. In a multivariable analysis, mild to moderate ED or moderate ED (IIEF-erectile function score ≤18) was significantly associated with having a mining-related job (adjusted odds ratio [aOR], 2.6; 95% CI, 1.3-5.3), work seniority Ë5 years (aOR, 2.3; 95% CI, 1.1-4.6), alcohol consumption (aOR, 2.8; 95% CI, 1.2-6.7), and aphrodisiacs use (aOR, 4.2; 95% CI, 2.2-8.0). Mediation analysis showed that marital relationship partially mediated the relation between work seniority >5 years in mining and ED. Clinical Implications: The high prevalence of ED found in artisanal mine workers indicates that work-related factors should be considered as possibly contributing, directly or indirectly, to sexual dysfunction in men. Strengths and Limitations: Strengths include being the first epidemiologic study documenting ED with validated questionnaires and its possible determinants, including exposure to toxic metals, among young artisanal miners vs a suitable control group. Limitations are the cross-sectional design with convenience sampling and absence of objective confirmation of ED. Conclusion: As compared with controls, miners reported poorer sexual function and lower quality of their marital relationship, and they had lower free testosterone levels, which may be due to their high exposure to trace metals.
RESUMO
BACKGROUND: Thousands of artisanal workers are exposed to mineral dusts from various origins in the African Copperbelt. We determined the prevalence of respiratory symptoms, pulmonary function, and urinary metals among artisanal stone-crushers in Lubumbashi. METHODS: We conducted a cross-sectional study of 48 male artisanal stone-crushers and 50 male taxi-drivers using a standardized questionnaire and spirometry. Concentrations of trace metals were measured by Inductively Coupled - Plasma Mass Spectrometry (ICP-MS) in urine spot samples. RESULTS: Urinary Co, Ni, As, and Se were higher in stone-crushers than in control participants. Wheezing was more prevalent (p = 0.021) among stone-crushers (23%) than among taxi-drivers (6%). In multiple logistic regression analysis, the job of a stone-crusher was associated to wheezing (adjusted Odds Ratio 4.45, 95% Confidence Interval 1.09-18.24). Stone-crushers had higher values (% predicted) than taxi-drivers for Forced Vital Capacity (105.4 ± 15.9 vs. 92.2 ± 17.8, p = 0.048), Forced Expiratory Volume in 1 Second (104.4 ± 13.7 vs. 88.0 ± 19.6, p = 0.052), and Maximum Expiratory Flow at 25% of the Forced Vital Capacity (79.0.1 ± 20.7 vs. 55.7 ± 30.1, p = 0.078). CONCLUSION: Stone-crushers were more heavily exposed to mineral dust and various trace elements than taxi-drivers, and they had a fourfold increased risk of reporting wheezing, but they did not have evidence of more respiratory impairment than taxi-drivers.
