Denosumab and breast cancer risk in postmenopausal women: a population-based cohort study.

BACKGROUND: Denosumab inhibits the receptor activator of nuclear factor κB (RANK) pathway and is used to treat osteoporosis. Emerging evidence suggests RANK-blockade may play a role in mammary tumourigenesis. Thus, we undertook a population-based study of denosumab use and breast cancer risk in a large cohort of postmenopausal women. METHODS: We included women 67+ years with prior bisphosphonate use who filled a first prescription for denosumab. They were matched on age, date, cumulative prior use of and time since last use of a bisphosphonate to women with no history of denosumab. Cox proportional hazards was used to estimate the hazard ratio (HR) of breast cancer with denosumab use. RESULTS: A total of 100,368 women were included in the analysis with 1271 incident breast cancer events. Denosumab use was associated with a 13% decreased breast cancer risk (HR = 0.87; 95% CI 0.76-1.00). There was no relationship between increasing number of denosumab doses and breast cancer risk (P-trend = 0.15). CONCLUSION: These findings suggest a potential protective effect of ever denosumab use on breast cancer risk in a cohort of older women previously treated with bisphosphonates.

Adherence to oral antiretroviral therapy in Canada, 2010-2020.

OBJECTIVE: To assess antiretroviral therapy (ART) adherence among people with HIV (PWH) in Canada and identify baseline characteristics associated with suboptimal adherence (<95%). DESIGN: Retrospective observational study using data from the National Prescription Drug Utilization Information System and Régie de l'assurance maladie Quebec (RAMQ) Public Prescription Drug Insurance Plan. METHODS: This analysis included PWH aged 18 years or older who initiated an ART regimen and were followed for at least 12 months (2010-2020). Patient characteristics were summarized using medical/pharmacy claims data from seven provinces (Alberta, Manitoba, New Brunswick, Newfoundland and Labrador, Ontario, Saskatchewan, and Quebec). ART regimen at index date (first dispensing of a regimen including a core agent) was defined as a single-tablet or multitablet regimen (MTR). Adherence was calculated using a Proportion of Days Covered approach, based on ART dispensing, recorded between April 2010 and the last available date. Multivariate linear regression analysis was used to determine correlations between suboptimal adherence and baseline characteristics. RESULTS: We identified 19 322 eligible PWH, 44.7% of whom had suboptimal adherence (<95%). Among 12 594 PWH with evaluable baseline data, 10 673 (84.8%) were ART-naive, 74.2% were men, mean age was 42.9 years, and 54.1% received a MTR as their ART. Based on multivariate regression analysis, suboptimal adherence was significantly associated with multitablet ART ( P  < 0.001) and younger age ( P  < 0.001) but not sex. CONCLUSION: Almost half of adult PWH in Canada had suboptimal adherence to ART. Better understanding of factors influencing adherence may help address gaps in current care practices that may impact adherence.

History and publication trends in the diffusion and early uptake of indirect comparison meta-analytic methods to study drugs: animated coauthorship networks over time.

OBJECTIVE: To characterise the early diffusion of indirect comparison meta-analytic methods to study drugs. DESIGN: Systematic literature synthesis. DATA SOURCES: Cochrane Database of Systematic Reviews, EMBASE, MEDLINE, Scopus and Web of Science. STUDY SELECTION: English language papers that used indirect comparison meta-analytic methods to study the efficacy or safety of three or more interventions, where at least one was a drug. DATA EXTRACTION: The number of publications and authors was plotted by year and type: methodological contribution, review or empirical application. Author and methodological details were summarised for empirical applications, and animated coauthorship networks were created to visualise contributors by country and affiliation type (academia, industry, government or other) over time. RESULTS: We identified 477 papers (74 methodological contributions, 42 reviews and 361 empirical applications) by 1689 distinct authors from 1997 to 2013. Prior to 2002, only three applications were published, with contributions from the USA (n=2) and Canada (n=1). The number of applications gradually increased annually with rapid uptake between 2011 and 2013 (n=254, 71%). Early diffusion occurred primarily in Europe with the first application credited to the UK in 2003. Application spread to other European countries in 2005, and may have been supported by regulatory requirements for drug approval. By the end of 2013, contributions included 49% credited to Europe (22% UK, 27% other), 37% credited to North America (11% Canada, 26% USA) and 14% from other regions. CONCLUSION: Indirect comparison meta-analytic methods are an important innovation for health research. Although Canada and the USA were the first to apply these methods, Europe led their diffusion. The increase in uptake of these methods may have been facilitated by acceptance by regulatory agencies, which are calling for more comparative drug effect data to assist in drug accessibility and reimbursement decisions.

Diffusion of Innovations model helps interpret the comparative uptake of two methodological innovations: co-authorship network analysis and recommendations for the integration of novel methods in practice.

OBJECTIVE: The objective of this study was to characterize the diffusion of methodological innovation. STUDY DESIGN AND SETTING: Comparative case study analysis of the diffusion of two methods that summarize confounder information into a single score: disease risk score (DRS) and high-dimensional propensity score (hdPS). We completed systematic searches to identify DRS and hdPS papers in the field of pharmacoepidemiology through to the end of 2013, plotted the number of papers and unique authors over time, and created sociograms and animations to visualize co-authorship networks. First and last author affiliations were used to ascribe institutional contributions to each paper and network. RESULTS: We identified 43 DRS papers by 153 authors since 1981, reflecting slow uptake during initial periods of uncertainty and broader diffusion since 2001 linked to early adopters from Vanderbilt. We identified 44 hdPS papers by 147 authors since 2009, reflecting rapid and integrated diffusion, likely facilitated by opinion leaders, early presentation at conferences, easily accessible statistical code, and improvement in funding. Most contributions (87% DRS, 96% hdPS) were from North America. CONCLUSION: When proposing new methods, authors are encouraged to consider innovation attributes and early evaluation to improve knowledge translation of their innovations for integration into practice, and we provide recommendations for consideration.