Sex differences in stroke reperfusion therapy in Aotearoa (New Zealand)

Abstract

Background and aims: Stroke is a leading cause of death in Aotearoa (New Zealand), and stroke reperfusion therapy is a key intervention. Sex differences in stroke care have previously been asserted internationally. This study assessed potential differences in stroke reperfusion rates and quality metrics by sex in Aotearoa (New Zealand).

Methods: This study used data from three overlapping sources. The National Stroke Reperfusion Register provided 4-year reperfusion data from 2018 to 2021 on all patients treated with reperfusion therapy (intravenous thrombolysis and thrombectomy), including time delays, treatment rates, mortality and complications. Linkage to Ministry of Health administrative and REGIONS Care study data provided an opportunity to control for confounders and explore potential mechanisms. T-test and Wilcoxon rank-sum analyses were used for continuous variables, while the chi-squared test and logistic regression were used for comparing dichotomous variables.

Results: Fewer women presented with ischaemic stroke (12 186 vs 13 120) and were 4.2 years older than men (median (interquartile range (IQR)) 79 (68-86) vs 73 (63-82) years). Women were overall less likely to receive reperfusion therapy (13.9% (1704) vs 15.8% (2084), P < 0.001) with an adjusted odds ratio of 0.83 (0.77-0.90), P < 0.001. The adjusted odds ratio for thrombolysis was lower for women (0.82 (0.76-0.89), P < 0.001), but lower rates of thrombectomy fell just short of statistical significance ((0.89 (0.79-1.00), P = 0.05). There were no significant differences in complications, delays or documented reasons for non-thrombolysis.

Conclusions: Women were less likely to receive thrombolysis, even after adjusting for age and stroke severity. We found no definitive explanation for this disparity.

Keywords: clinical; health equity; ischaemic stroke; reperfusion; sex; stroke.