Showing papers by "Wen Qi Gan published in 2014"

Association between systemic inflammatory markers and serum prostate-specific antigen in men without prostatic disease - the 2001-2008 National Health and Nutrition Examination Survey.

Abstract: Background Serum prostate specific antigen (PSA) may be elevated in otherwise healthy men; systemic inflammation has been associated with cancer. The study of systemic inflammatory markers in men without clinical prostate disease, but with elevated PSA may characterize the subgroup of men at higher risk for subsequent prostate cancer. Methods We investigated the associations between systemic inflammatory markers and serum PSA in 3,164 healthy men without prostatic disease, aged >40 years, from the 2001 to 2008 U.S. National Health and Nutrition Examination Survey (NHANES). Serum total PSA levels and concentrations of serum C-reactive protein (CRP) and plasma fibrinogen, neutrophil count, lymphocyte count, and platelet count were recorded. Neutrophil-lymphocyte ratio (NLR) ratio and platelet-lymphocyte (PLR) ratio were calculated. PSA elevation was defined as levels equal or greater than 4 ng/ml. Results Elevated serum PSA (194 men, 6.1% of the total), was significantly associated with plasma fibrinogen (ORmultiv = 1.88; 95% CI, 1.09-3.25), and NLR (ORmultiv = 1.14; 95% CI, 1.03-1.26), after adjustment for age, smoking, body mass index, education, race, co-morbidities, and use of medications. Conclusions Markers of systemic inflammation were associated with elevated PSA in men without known prostatic disease. Future studies are needed to examine these markers' relationship with prostate cancer occurrence and progression.

Long-term exposure to traffic-related air pollution and progression of carotid artery atherosclerosis: a prospective cohort study

Abstract: Objectives Epidemiological studies have demonstrated associations between long-term exposure to traffic-related air pollution and coronary heart disease (CHD). Atherosclerosis is the principal pathological process responsible for CHD events, but effects of traffic-related air pollution on progression of atherosclerosis are not clear. This study aimed to investigate associations between long-term exposure to traffic-related air pollution and progression of carotid artery atherosclerosis. Setting Healthy volunteers in metropolitan Vancouver, Canada. Participants and outcome measures 509 participants aged 30–65 years were recruited and followed for approximately 5 years. At baseline and end of follow-up, participants underwent carotid artery ultrasound examinations to assess atherosclerosis severity, including carotid intima-media thickness, plaque area, plaque number and total area. Annual change of each atherosclerosis marker during the follow-up period was calculated as the difference between these two measurements divided by years of follow-up. Living close to major roads was defined as ≤150 m from a highway or ≤50 m from a major road. Residential exposures to traffic-related air pollutants including black carbon, fine particles, nitrogen dioxide and nitric oxide were estimated using high-resolution land-use regression models. The data were analysed using general linear models adjusting for various covariates. Results At baseline, there were no significant differences in any atherosclerosis markers between participants living close to and those living away from major roads. After follow-up, the differences in annual changes of these markers between these two groups were small and not statistically significant. Also, no significant associations were observed with concentrations of traffic-related air pollutants including black carbon, fine particles, nitrogen dioxide and nitric oxide. Conclusions This study did not find significant associations between traffic-related air pollution and progression of carotid artery atherosclerosis in a region with lower levels and smaller contrasts of ambient air pollution.