Biomedical subjects

Kristan J Aronson

Publications and source records attributed to Kristan J Aronson.

6 recordsLinked to original sources

PubMed2006

Pesticides and polychlorinated biphenyls as potential risk factors for erectile dysfunction.

While it is biologically plausible that environmental chemicals such as pesticides and polychlorinated biphenyls (PCBs) with suspected hormone disrupting properties may have an impact on risk of erectile dysfunction (ED), few epidemiologic studies have assessed this potential association. In a clinic-based case-control study in Kingston, Ontario, consenting subjects completed a questionnaire and donated 15 mL of blood for analysis of organochlorines and lipids by gas chromatography. Exposures were compared for 101 cases with ED and 234 comparable control subjects. For most PCB congeners and organochlorine pesticides, geometric mean levels are similar for cases and controls. Multivariate logistic regression results do not show an increased or decreased risk of ED associated with levels of most detectable environmental substances after adjustment for age, total lipids, and confounders. Levels of 2 of the ubiquitous chlorinated pesticides, oxychlordane and trans-nonachlor, which are highly correlated, appear to associate with a reduced risk of ED, but the role of chance cannot be ruled out. To our knowledge, this study is the first to investigate the possible relationship between plasma levels of organochlorines and ED risk, and results do not provide evidence of an association.

Aged↗

PubMed2005

Dietary patterns and risk of prostate cancer in Ontario, Canada.

Dietary patterns reflect combinations of dietary exposures, and here we examine these in relation to prostate cancer risk. In a case-control study, 80 incident primary prostate cancer cases and 334 urology clinic controls were enrolled from 1997 through 1999 in Kingston, Ontario, Canada. Food-frequency questionnaires were completed prior to diagnosis and assessed intake in the 1-year period 2-3 years prior to enrollment. Among controls, dietary intake was used in principal components analyses to identify patterns that were then evaluated with all subjects in relation to prostate cancer risk using unconditional logistic regression, controlling for age. Four dietary patterns were identified: Healthy Living, Traditional Western, Processed and Beverages. Increased prostate cancer risk is apparent in relation to the Processed pattern, composed of processed meats, red meats, organ meats, refined grains, white bread, onions and tomatoes, vegetable oil and juice, soft drinks and bottled water. The OR for the highest tertile compared to baseline is 2.75 (95% CI 1.40-5.39), with a dose-response pattern (trend test p < 0.0035). Our results suggest that a dietary pattern including refined grain products, processed meats and red and organ meats contributes to increased prostate cancer risk. Since dietary information was collected before subjects knew their diagnosis, recall bias was avoided.

Aged↗

PubMed2005

Twenty-four-hour light exposure and melatonin levels among shift workers.

OBJECTIVES: We sought to measure melatonin levels and 24-hour light intensity exposure in health care workers over a 7-day period in natural occupational and residential settings. METHODS: Five office workers and 17 nurses working either days or rotating night and day shifts wore a device to record light intensity exposure for one or two 7-day periods, completed a questionnaire, and provided three saliva samples for melatonin. RESULTS: Rotating shift workers had irregular light exposure patterns and abnormal melatonin levels compared with those working days. In addition to lower-than-normal melatonin levels during sleep periods, rotating shift workers exhibited higher-than-normal melatonin levels on arising and during work. Self-reported years of shift work were correlated with measured melatonin and light. CONCLUSIONS: Rotating shift work is supported as a surrogate for exposure to light-at-night and circadian disruption.

Adult↗

PubMed2005

Smoking and other lifestyle factors in relation to erectile dysfunction.

OBJECTIVE: To assess the association between erectile dysfunction (ED) and various lifestyle and medical factors, including smoking and cardiovascular disease (CVD) medications, among men attending urology clinics in Kingston, Canada. SUBJECTS AND METHODS: We conducted a case-control study of men aged 50-80 years in Kingston, Ontario who agreed to participate at visits to urology clinics during 1997-99. We compared 101 men with clinically diagnosed ED and 234 controls with various benign urological conditions. All men completed a questionnaire on lifestyle and medical factors. RESULTS: Men with ED were twice as likely to be former smokers (odds ratio 2.2, 95% confidence interval, 1.2-3.9), and cumulative smoking in pack-years suggests a dose-response pattern with the risk of ED. Having diabetes was associated with double the risk of ED, and increased alcohol intake appeared to increase the risk. CONCLUSION: There was a greater risk of ED among former smokers, and the suggestion of a dose-response relationship with cumulative smoking.

Age Distribution↗

PubMed2004

Breast tissue organochlorine levels and metabolic genotypes in relation to breast cancer risk Canada.

Genes that metabolize the rate of clearance of environmental carcinogens may be candidate genes for cancer susceptibility. There is some data to suggest that exposure to environmental pesticides and other organochlorine pollutants is a risk factor to breast cancer. It is therefore reasonable to ask if variants in the genes responsible for the metabolic activation of organochlorines are associated with different tissue burdens of organochlorines and if these variants modify the risk of breast cancer in the population. We conducted a case-control study of women who underwent an excision biopsy for suspected breast cancer in a Toronto hospital from 1995 to 1997. Patients are residents of the Greater Toronto Area and are primarily Caucasian of European descent. Cases were women with invasive breast cancer (n = 70) and controls (n = 69) were women diagnosed with benign disease, frequency matched by age to cases. Levels of organochlorines were measured in benign breast tissue and seven polymorphisms in five candidate genes were genotyped. In general, women who carried inactive alleles of the GSTM1 had higher levels of breast organochlorines, and were at modestly increased risk of breast cancer (odds ratio = 2.2; 95% CI = 1.1-4.4). However, multiple comparisons were made and generally our data do not support the hypothesis that organochlorines increase the risk of breast cancer among subgroups of women with specific metabolic genotypes.

Adult↗

PubMed2003

Dietary predictors of concentrations of polychlorinated biphenyls in breast adipose tissue of women living in Ontario, Canada.

The authors evaluated dietary predictors of concentrations of 11 polychlorinated biphenyls (PCBs) in breast adipose tissue from 190 women with benign breast disease who live in Ontario, Canada. Consumption of fish was positively correlated with, and the most consistent dietary predictor of, breast tissue PCB levels. Dietary predictors accounted for < 8% of the variation in breast adipose tissue PCB levels. Age was positively and most strongly associated with tissue PCB levels, perhaps representing long-term dietary intake and the complex interplay of absorption, metabolism, distribution, and excretion.

Adipose Tissue↗