Showing papers by "Saskatchewan Health published in 2006"

Use of antidepressants and risk of colorectal cancer: a nested case-control study

Abstract: Summary Background Animal studies suggest that selective serotonin reuptake inhibitors (SSRI) retard the growth of colorectal tumours, whereas tricyclic antidepressants increase the risk of colorectal cancer. We aimed to assess whether SSRI use was associated with a decreased risk of colorectal cancer, and tricyclic-antidepressant use with an increased risk of colorectal cancer. Methods We did a population-based nested case-control study from Jan 1, 1981, to Dec 31, 2000, of people aged 5–85 years who were registered with Saskatchewan Health and eligible for prescription-drug benefit. Between Jan 1, 1981, and Dec 31, 2000, 6544 cases with colorectal cancer were identified from the Saskatchewan Cancer Agency registry and analysed for use of tricyclic antidepressants; between Jan 1, 1991, and Dec 31, 2000, 3367 cases with colorectal cancer were identified from the Saskatchewan Cancer Agency registry and analysed for SSRI use. For every case, four eligible controls matched for age, sex, and calendar time (ie, free of any cancer in calendar month of case diagnosis) were selected randomly by a statistician who used incidence density sampling. By use of conditional logistic regression, we assessed incidence-rate ratios of having colorectal cancer in association with use of antidepressants, analysing dose and time of use. Findings A decreased risk of colorectal cancer was associated with high (ie, >6·0×10 −6 mol per day) daily SSRI dose during 0–5 years before diagnosis (incidence-rate ratio 0·70 [95% CI 0·50–0·96], p for trend=0·0172), adjusted for age, sex, use of non-steroidal anti-inflammatory drugs in the same period, and SSRI use during 6–10 years before index date (ie, date of diagnosis for a case and the same date for matched controls). No consistent relation was recorded for risk of colorectal cancer and use of tricyclic antidepressants. Interpretation SSRI use might inhibit the growth of colorectal tumours through an antipromoter effect or direct cytotoxic effect. Further investigation is needed, with more complete assessment of confounders such as lifestyle factors (eg, diet), use of drugs, and comorbidity (eg, diabetes or inflammatory bowel disease) that might affect the occurrence of colorectal cancer.

Chronic obstructive pulmonary disease severity and cardiovascular outcomes.

Abstract: To identify predictors of chronic obstructive pulmonary disease (COPD) severity and assess the relation between COPD severity and risk of cardiovascular outcomes A␣cohort of patients with diagnosed and treated COPD was compiled from the Saskatchewan Health longitudinal databases We used multivariate modeling to identify predictors of hospitalization for COPD as an indicator of COPD severity, and we used the model to characterize patients according to quintiles of COPD severity These severity levels were used as independent variables in multivariate models of cardiovascular outcomes Determinants of COPD severity included emphysema, recent nebulizer use, home oxygen services, corticosteroid use, frequent bronchodilator use, pneumonia and prior COPD exacerbation The 20% of patients with the highest COPD severity were 127 (CI: 107–150) times more likely to have arrhythmia, 125 (CI: 107–146) times more likely to have ischemic heart disease, 138 (CI: 111–171) times more likely to have angina, 228 (CI: 195–266) times more likely to have congestive heart failure, and 163 (CI: 122–216) times more likely to die of cardiovascular causes than the least severe 20% of patients Patients with more severe COPD, as defined by our model, had higher cardiovascular morbidity and mortality than patients with less severe COPD

Seroprevalence of West Nile virus in Saskatchewan's Five Hills Health Region, 2003.

Abstract: Background: The Five Hills Health Region of Saskatchewan reported the highest West Nile virus (WNV) case rates in the 2003 outbreak. A serologic and telephone survey was undertaken to assess the seroprevalence of the virus and the knowledge, attitudes and behaviours of the residents. Methods: Respondents had to be at least 18 years of age, and residents of the Five Hills Health Region between July 1 st and September 15 th , 2003. Blood samples of respondents were tested at the National Microbiology Laboratory for flavivirus immunoglobulin using a WNV IgG ELISA and plaque reduction neutralization test. Descriptive analyses performed related to respondents’ demographics, knowledge, attitudes, behaviours, and seropositivity. WNV infection risk was assessed using odds ratio. Results: There were 619 questionnaire respondents, of whom 501 donated a blood sample. The seroprevalence of WNV in the Five Hills Health Region was 9.98% (95% CI 7.37-12.59%). Seropositivity of rural areas was 16.8% and urban was 3.2%. Most (97%) of participants thought WNV was an important health issue. Forty-eight percent of the participants used insect repellents containing DEET most of the time. There was good knowledge regarding WNV transmission and prevention of the spread of WNV. Rural compared to urban residents were six times more likely to be positive for WNV (OR=6.13, 95% CI 2.82-13.34). Interpretation: This is the highest seroprevalence rate of West Nile virus recorded in North America thus far. Many factors could have influenced this outbreak, such as eco-region, early prolonged hot weather, level of mosquito control programs, urban and rural community differences, and personal protective behaviours. MeSH terms: West Nile virus; seroepidemiologic study; Saskatchewan; knowledge, attitude, behavior

Risk of breast cancer in association with exposure to two different groups of tricyclic antidepressants.

Abstract: Purpose In 2002, we reported an epidemiological study in which we found that some tricyclic antidepressants (identified as genotoxic in Drosophila Melanogaster) were associated with an increased risk of breast cancer, when exposure took place 11–15 years before the date of diagnosis. The implications of the results found lead us to carry out a separate case-control study, using the same source population, to validate the conclusions drawn from our previous study. Methods We accrued 7330 breast cancer cases, diagnosed between 1981 and 2000, and 29 320 controls matched on age and time. Results The association between exposure to genotoxic TCAs 11–15 years before diagnosis and the risk of breast cancer development was much weaker, as compared to what was reported in our previous study. The relative risk of breast cancer in women exposed to high doses of genotoxic TCAs 11–15 years before diagnosis was 1.17 (95%CI: 0.79–1.74), while in women exposed to high levels of non-genotoxic TCAs during the same period it was 0.95 (95%CI: 0.61–1.48). Conclusion In conclusion, we did not find supporting evidence for an increased risk of breast cancer among women exposed to TCAs up to 20 years in the past. Copyright © 2006 John Wiley & Sons, Ltd.