Grant: Fellowship - Priority Announcement: Drug Safety and Effectiveness

Even with the rigorous premarket approval process for medicines, adverse outcomes might not be recognized before a drug is in general use. Rare effects are likely to be identified only through the conduct of extremely large post market clinical trials or extensive monitoring efforts. Policy-makers are constantly seeking for updated analyses that can help further assess drug effectiveness and safety. Certain antidepressants, known as serotonin reuptake inhibitors (SSRIs) and serotonin/norepinephrine reuptake inhibitors (SNRIs), may be particularly harmful to bone and increase the risk of fractures, especially in the elderly population. The objective of this study is to compare the risk of fractures in SSRI users and SNRI users versus non-users of either of these medications. We will use data available on administrative health databases combined with clinical cohort datasets. Administrative databases are appropriate for this type of research because they provide large sample size. However, they usually lack detailed clinical information, which can be important to understand the complex relationship between antidepressants, current depression, and other factors that might themselves increase the risk of fractures. Thus, by linking the administrative data with clinical cohort, the benefits of both types of data can be maximized. To study the effect of these drugs in increasing the risk of fractures, we will first create 3 distinct groups based on exposure or not to (i) SSRIs; (ii) SNRIs; iii) other antidepressants. We will then measure and compare the frequency of fractures in each group, to see if there is an additional risk in individuals taking SSRI or/and SNRI. Our definition of fracture is intended to identify events likely to be related to osteoporosis. This study addresses important knowledge gaps, as identified by Health Canada and decision-makers responsible for provincial formularies, and will thus help shape effective policy and patient-centered care.