Platform Presentation The Joint Annual Meeting of the Stroke Society of Australasia (SSA) and Smartstrokes 2023

Sex Differences in Prescribing and Dispensing of Antihypertensive Medications After Stroke: A Linked Registry Study (#76)

Lachlan L Dalli 1 , Nadine E Andrew 2 3 , Joosup Kim 1 4 , Muideen T Olaiya 1 , Dominique A Cadilhac 1 4 , David Ung 2 3 , Hoang T Phan 5 , Amanda G Thrift 2 3 , Seana L Gall 5 , Mark R Nelson 5 , Monique F Kilkenny 1 4
  1. Stroke and Ageing Research, Department of Medicine, Monash University, Clayton, Victoria, Australia
  2. National Centre for Healthy Ageing, Frankston, Victoria, Australia
  3. Peninsula Clinical School, Central Clinical School, Monash University, Frankston, Victoria, Australia
  4. The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Heidelberg, Victoria, Australia
  5. Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia

Background: Antihypertensive medications are recommended for long-term secondary prevention of stroke, irrespective of sex.

Aims: To examine differences in prescribing and dispensing of antihypertensive medications after stroke between men and women.

Methods: Retrospective cohort study using patient-level data from the Australian Stroke Clinical Registry ([AuSCR] 2012-2016, Victoria and Queensland), linked with national pharmaceutical and death records until 2018 (PRECISE project). To minimise confounding by indication, the analysis was limited to people with first-ever stroke who were alive at 90 days. AuSCR data were used to determine patient characteristics (e.g. sex) and prescription of antihypertensive medications at hospital discharge. Linked pharmaceutical claims data were used to investigate dispensing of antihypertensive medications in the community within 90 days post-discharge. Sex differences in prescribing and dispensing were assessed using multivariable logistic regression models, adjusted for age, comorbidities, stroke severity, year, and hospital clustering.

Results: Of 13,448 people with first-ever stroke who survived to 90 days, 43% were women. Compared with men, women were older (74 vs 70 years; p=0.001) and more likely to have experienced a severe stroke (unable to walk on admission 54% vs 50%; p=0.001). In adjusted models, women were less often prescribed antihypertensive medications after stroke than men (adjusted odds ratio [aOR] 0.87 [95% CI: 0.80–0.95]). Within 90 days, women were also less often dispensed antihypertensive medications in the community than men (aOR 0.85 [95% CI: 0.79–0.92]). Of those dispensed antihypertensives within 90 days, women were more likely to receive dual or triple antihypertensive therapy than men (aOR 1.20 [95% CI: 1.10–1.30]).

Conclusion: Although women were less likely to be prescribed or dispensed antihypertensive medications after stroke, they were more likely to receive combination therapy. Efforts to reduce these sex disparities in prescribing and dispensing of antihypertensive medications are needed to ensure equitable secondary prevention of stroke.