Variability in prescription medication coverage for children and youth across Canada: A scoping review.

BACKGROUND: Prescription medication coverage in Canada is provided by at least 14 public drug plans and thousands of private insurance plans. Previous literature suggests that public plan coverage varies, and little is known about private drug plans. OBJECTIVE: Undertake a scoping review of recent literature evaluating coverage of prescription medication for children and youth under 25 across Canada. METHODS: Bibliographic databases (Embase, CINAHL, Web of Science, Medline) and gray literature sources were screened. Papers published between January 2005 and July 2021, focusing on prescription medication coverage for Canadians under 25 years were identified. RESULTS: Of 562 titles and abstracts, 9 reports met our criteria. One report estimates 3.3% of children and youth in 10 provinces are uninsured (i.e. not eligible), with non-enrollment for those eligible for public plans ranging from 12% to 49%. Minimal information on private drug plan coverage was identified. Demographic- or income-based public drug plans report coverage in 12 of 14 jurisdictions. Those covered by a demographic- or income-based plan have access to jurisdictional formularies. 3 of 14 public plans report no cost sharing for children. CONCLUSION: There is less variability in who and what is covered and more in how much is covered (i.e., details of cost sharing). More research is needed to adequately understand the gaps in coverage and its impact on children and youth.

Drug-drug interactions with warfarin: A systematic review and meta-analysis.

AIMS: The objective of this paper is to systematically review the literature on drug-drug interactions with warfarin, with a focus on patient-important clinical outcomes. METHODS: MEDLINE, EMBASE and the International Pharmaceutical Abstract (IPA) databases were searched from January 2004 to August 2019. We included studies describing drug-drug interactions between warfarin and other drugs. Screening and data extraction were conducted independently and in duplicate. We synthesized pooled odds ratios (OR) with 95% confidence intervals (CIs), comparing warfarin plus another medication to warfarin alone. We assessed the risk of bias at the study level and evaluated the overall certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: Of 42 013 citations identified, a total of 72 studies reporting on 3 735 775 patients were considered eligible, including 11 randomized clinical trials and 61 observational studies. Increased risk of clinically relevant bleeding when added to warfarin therapy was observed for antiplatelet (AP) regimens (OR = 1.74; 95% CI 1.56-1.94), many antimicrobials (OR = 1.63; 95% CI 1.45-1.83), NSAIDs including COX-2 NSAIDs (OR = 1.83; 95% CI 1.29-2.59), SSRIs (OR = 1.62; 95% CI 1.42-1.85), mirtazapine (OR = 1.75; 95% CI 1.30-2.36), loop diuretics (OR = 1.92; 95% CI 1.29-2.86) among others. We found a protective effect of proton pump inhibitors (PPIs) against warfarin-related gastrointestinal (GI) bleeding (OR = 0.69; 95% CI 0.64-0.73). No significant effect on thromboembolic events or mortality of any drug group used with warfarin was found, including single or dual AP regimens. CONCLUSIONS: This review found low to moderate certainty evidence supporting the interaction between warfarin and a small group of medications, which result in increased bleeding risk. PPIs are associated with reduced hospitalization for upper GI bleeding for patients taking warfarin. Further studies are required to better understand drug-drug interactions leading to thromboembolic outcomes or death.