For this assignment, which was first presented in Week 1, you are to find an article on epidemiology in the news and write a 250- to 350-word summary about the article. The article should not be from...

CMAJ Research Pneumococcal vaccination and risk of myocardial infarction François Lamontagne MD MSc, Marie-Pierre Garant PhD, Jean-Christophe Carvalho MD, Luc Lanthier MD MSc, Marek Smieja MD PhD, Danielle Pilon MD MSc @@ See related commentary by Madjid, page 749 Animal experiments have shown that pneumococcal vacci- Abstract 6 nation reduces the extent of atherosclerotic lesions. We Background: Based on promising results from laboratory hypothesized that antibodies directed against Streptococcus studies, we hypothesized that pneumococcal vaccination pneumoniae also recognize oxidized low-density lipoprotein would protect patients from myocardial infarction. (LDL) and impede the formation of foam cells. Interestingly, a retrospective cohort study involving World War II veterans Methods: We conducted a hospital-based case–control who had undergone splenectomy documented excess mortal- study that included patients considered to be at risk of 7 myocardial infarction. We used health databases to obtain ity rates from both pneumonia and ischemic heart disease. hospital diagnoses and vaccination status. We compared More recent data have suggested that acute pneumococcal patients who had been admitted for treatment of myocar- infections, but not vaccinations, increase the risk of vascular dial infarction with patients admitted to a surgical depart- 8 events; however, the duration of vaccination exposure con- ment in the same hospital for a reason other than myocar- sidered in that study was limited. dial infarction between 1997 and 2003. Our primary objective was to evaluate the association be- Results: We found a total of 43 209 patients who were at tween pneumococcal vaccination and the risk of myocardial risk; of these, we matched 999 cases and 3996 controls ac- infarction. We also explored whether any effect of vaccina- cording to age, sex and year of hospital admission. Cases tion on the risk of infarction waned over time. were less likely than controls to...