Objectives. We explored the effects of social determinants of health on pandemic H1N1 2009 influenza severity and the role of clinical risk factors in mediating such associations. Methods. We used multivariate logistic regression with generalized estimating equations to examine the associations between individual- and ecological-level social determinants of health and hospitalization for pandemic H1N1 2009 illness in a case-control study in Ontario, Canada. Results. During the first pandemic phase (April 23–July 20, 2009), hospitalization was associated with having a high school education or less and living in a neighborhood with high material or total deprivation. We also observed the association with education in the second phase (August 1–November 6, 2009). Clinical risk factors for severe pandemic H1N1 2009 illness mediated approximately 39% of the observed association. Conclusions. The main clinical risk factors for severe pandemic H1N1 2009 illness explain only a portion of the associations observed between social determinants of health and hospitalization, suggesting that the means by which the social determinants of health affect pandemic H1N1 2009 outcomes extend beyond clinically recognized risk factors.

Background: Cataract surgery is the most common operative procedure performed in Canada, and how patients are affected by wait times for this surgery has important clinical, public health and health policy considerations. We conducted a systematic review to understand the relation between wait time for cataract surgery and patient outcomes and the variables that modify this relation. Methods:We performed an electronic search of 11 databases and the proceedings of 4 conferences. The search was restricted to studies published after the transition to phacoemulsification (1990). We assessed the quality of the included studies using the Jadad Scale for randomized controlled trials and the Newcastle-Ottawa Scale for cohort and case-control studies. The data were found to be inappropriate for meta-analysis, thus we performed a qualitative synthesis. Results:We found a total of 27 studies that met our inclusion criteria. When these studies were reviewed, a dichotomy was observed for the wait time-outcome relation: outcomes associated with wait times of ≤ 6 weeks were better than outcomes associated with wait times of ≥ 6 months. Patients who waited more than 6 months to receive cataract surgery experienced more vision loss, a reduced quality of life and had an increased rate of falls compared with patients who had wait times of less than 6 weeks. The outcomes associated with wait times between 6 weeks and 6 months remain unclear. Interpretation:Patients who wait more than 6 months for cataract surgery may experience negative outcomes during the wait period, including vision loss, a reduced quality of life and an increased rate of falls. CMAJ 2007;176(9):1285-90 Abstract

Background Less than 10% of pancreatic cancer cases survive five years, yet its etiology is not well understood. Studies suggest allergies are associated with reduced pancreatic cancer risk. Our study collected additional information on allergies (including skin prick test results and differentiation of allergic/non-allergic asthma), and is the first to assess possible confounding by allergy medications. Methods A population-based case-control study was designed to comprehensively assess the association between allergy and pancreatic cancer risk. Pancreas cancer cases were diagnosed during 2011-2012, and identified through the Ontario Cancer Registry (345 cases). Population-based controls were identified using random digit dialing and age/sex frequency matched to cases (1285 controls). Questionnaires collected lifetime allergy history (type of allergy, age at onset, skin prick testing results), allergy medications, and established pancreas cancer risk factors. Logistic regression was used to estimate odd ratios and test potential confounders, including allergy medications. Results Hay fever was associated with a significant reduction in pancreatic cancer risk (AOR=0.68, 95% CI: 0.52-0.89), and reduction was greatest for those whose skin prick test was positive for hay fever allergens. No particular patterns were observed as regards age at onset and duration of allergy. Positive dust/mold allergy skin prick test and animal allergies were associated with a statistically significant reduced pancreatic cancer risk; AOR=0.49, 95% CI: 0.31-0.78 and AOR=0.68, 95% CI: 0.46-0.99, respectively. Asthma was not associated with pancreatic cancer risk. Conclusions/Impact These findings support the growing body of evidence that suggests certain allergies are associated with reduced pancreatic cancer risk.