1 Sun LY, et al. BMJ Open 2020;10:e044126. doi:10.1136/bmjopen-2020-044126 Open access Sex-specifc temporal trends in ambulatory heart failure incidence, mortality and hospitalisation in Ontario, Canada from 1994 to 2013: a population- based cohort study Louise Y Sun , 1,2,3 Lisa M Mielniczuk, 4 Peter P Liu, 4 Rob S Beanlands, 4 Sharon Chih, 4 Ross Davies, 4 Thais Coutinho, 4,5 Douglas S Lee, 2,6 Peter C Austin, 2 Anan Bader Eddeen, 2 Jack V Tu 2,7 To cite: Sun LY, Mielniczuk LM, Liu PP, et al. Sex-specifc temporal trends in ambulatory heart failure incidence, mortality and hospitalisation in Ontario, Canada from 1994 to 2013: a population-based cohort study. BMJ Open 2020;10:e044126. doi:10.1136/ bmjopen-2020-044126 ► Prepublication history and additional material for this paper are available online. To view these fles, please visit the journal online (http://dx.doi. org/10.1136/bmjopen-2020- 044126). Dr. Tu is deceased LYS and LMM are joint frst authors. Received 24 August 2020 Revised 07 October 2020 Accepted 06 November 2020 For numbered affliations see end of article. Correspondence to Dr Louise Y Sun; lsun@ottawaheart.ca Original research © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. ABSTRACT Objectives To examine the temporal trends in mortality and heart failure (HF) hospitalisation in ambulatory patients following a new diagnosis of HF. Design Retrospective cohort study Setting Outpatient Participants Ontario residents who were diagnosed with HF in an outpatient setting between 1994 and 2013. Primary and secondary outcome measures The primary outcome was all-cause mortality within 1 year of diagnosis and the secondary outcome was HF hospitalisation within 1 year. Risks of mortality and hospitalisation were calculated using the Kaplan-Meier method and the relative hazard of death was assessed using multivariable Cox proportional hazard models. Results A total of 352 329 patients were studied (50% female). During the study period, there was a greater decline in age standardised 1-year mortality rates (AMR) in men (33%) than in women (19%). Specifcally, female AMR at 1 year was 10.4% (95% CI 9.1% to 12.0%) in 1994 and 8.5% (95% CI 7.5% to 9.5%) in 2013, and male AMR at 1 year was 12.3% (95% CI 11.1% to 13.7%) in 1994 and 8.3% (95% CI 7.5% to 9.1%) in 2013. Conversely, age standardised HF hospitalisation rates declined in men (11.4% (95% CI 10.1% to 12.9%) in 1994 and 9.1% (95% CI 8.2% to 10.1%) in 2013) but remained unchanged in women (9.7% (95% CI 8.3% to 11.3%) in 1994 and 9.8% (95% CI 8.6% to 11.0%) in 2013). Conclusion Among patients with HF over a 20-year period, there was a greater improvement in the prognosis of men compared with women. Further research should focus on the determinants of this disparity and ways to reduce this gap in outcomes. INTRODUCTION Heart failure (HF) is a significant cause of morbidity and mortality for both women and men. 1 2 Despite the current era of guideline directed medical therapy, HF continues to be a leading cause of admis- sion to hospital. It is associated with a poor prognosis and contributes to 35% of cardio- vascular mortality in women. 3 Despite this, HF remains poorly understood in women, and women continue to be underrepre- sented in HF clinical trials. 4 The underlying mechanism of HF is often different in women and men, with women suffering more often from HF of a hypertensive rather than isch- aemic aetiology. 5 6 Important trends in the incidence and outcomes of hospitalised HF patients have been recently published 7 8 ; these studies suggest that the incidence of HF has declined in many inpatient cohorts, however, the prognosis of this disease remains poor. An in-depth understanding of the temporal trends in HF incidence and outcomes is also needed in the ambulatory setting, where the majority of HF cases are diagnosed and managed. Also, given the sex differences in comorbidities and outcomes in HF, it is not known if these temporal changes are modi- fied by sex. We, therefore, examined the sex differences in HF comorbidities, incidence, mortality and hospitalisation in a population- based ambulatory cohort from fiscal years 1994 to 2013. Strengths and limitations of this study ► First and largest population-based study to examine temporal, sex-specifc trends in heart failure (HF) outcomes in an ambulatory setting. ► The nature of our publicly funded healthcare system allowed for analysis of all patients diagnosed with HF in Ontario without selection bias. ► Information on ejection fraction was not available in the databases used. on February 19, 2022 by guest. Protected by copyright. http://bmjopen.bmj.com/ BMJ Open: first published as 10.1136/bmjopen-2020-044126 on 26 November 2020. Downloaded from