RESUMO
The disparities in stroke mortality between blacks and whites, as well as the increased stroke mortality in the "stroke belt" have long been noted. The reasons for these disparities have yet to be fully explained. The association between trace element status and cardiovascular diseases, including stroke, has been suggested as a possible contributor to the disparities in stroke mortality but has not been fully explored. The purpose of this study is to investigate distributions of four trace elements (arsenic, mercury, magnesium, and selenium) in the environment in relation to stroke risk. The study population (N=27,770) is drawn from the Reasons for Geographic and Racial Disparities in Stroke (REGARDS) cohort. Environmental distribution of each trace element was determined using data from the United States Geological Survey (USGS) and was categorized in quartiles. A proportional hazards model, adjusted for demographic data and stroke risk factors, was used to examine the association of interest. The results showed that higher selenium levels in the environment were associated with increased stroke risk, and the hazard ratio for the 4th quartile compared to the 1st quartile was 1.33 (95% CI: 1.09, 1.62). However, there was no statistically significant relationship between environmental arsenic, mercury or magnesium and the risk of stroke. Because of dietary and non-dietary exposure as well as bioavailability, further research using biomarkers is warranted to examine the association between these trace elements and the risk of stroke.
Assuntos
Meio Ambiente , Geografia , Grupos Raciais , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Oligoelementos/efeitos adversos , Idoso , Demografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/etnologiaRESUMO
Objectives. We estimated seroprevalence and correlates of selected infections in pregnant women and blood donors in a resource-limited setting. Methods. We performed a cross-sectional analysis of laboratory seroprevalence data from pregnant women and voluntary blood donors from facilities in Cameroon in 2014. Rapid tests were performed to detect hepatitis B surface antigen, syphilis treponemal antibodies, and HIV-1/2 antibodies. Blood donations were also tested for hepatitis C and malaria. Results. The seroprevalence rates and ranges among 7069 pregnant women were hepatitis B 4.4% (1.1-9.6%), HIV 6% (3.0-10.2%), and syphilis 1.7% (1.3-3.8%) with significant variability among the sites. Correlates of infection in pregnancy in adjusted regression models included urban residence for hepatitis B (aOR 2.9, CI 1.6-5.4) and HIV (aOR 3.5, CI 1.9-6.7). Blood donor seroprevalence rates and ranges were hepatitis B 6.8% (5.0-8.8%), HIV 2.2% (1.4-2.8%), syphilis 4% (3.3-4.5%), malaria 1.9%, and hepatitis C 1.7% (0.5-2.5%). Conclusions. Hepatitis B, HIV, and syphilis infections are common among pregnant women and blood donors in Cameroon with higher rates in urban areas. Future interventions to reduce vertical transmission should include universal screening for these infections early in pregnancy and provision of effective prevention tools including the birth dose of univalent hepatitis B vaccine.