Sex-Specific Association Between Socioeconomic Status and Stroke Mortality

Socioeconomic status and sex each independently influence stroke outcomes. However, their intersectional effects remain unclear. Accordingly, we sought to assess whether the association between socioeconomic status and outcomes in stroke varied by sex.

We conducted a retrospective cohort study using the National Inpatient Sample (2016-2021). Patients with a primary diagnosis of acute ischemic stroke, intracerebral hemorrhage, or subarachnoid hemorrhage were analyzed in separate cohorts. The primary exposure was socioeconomic status (ZIP code income quartile). Multivariable logistic regression was used to assess the effect of socioeconomic status on stroke outcomes. Significant first-order sex-income interactions were observed across all stroke subtypes; accordingly, we built sex-stratified models.

A total of 2 836 254 acute ischemic stroke, 406 550 intracerebral hemorrhage, and 134 510 subarachnoid hemorrhage admissions were included. In male patients, patients from the lowest quartile of ZIP code income quartile had significantly increased odds of inpatient mortality across acute ischemic stroke (odds ratio [OR], 1.11 [95% CI, 1.03-1.21], P=0.009), intracerebral hemorrhage (OR, 1.15 [95% CI, 1.05-1.25], P=0.002), and subarachnoid hemorrhage (OR, 1.46 [95% CI, 1.22-1.74], P<0.001). In female patients, ZIP code income quartile was not associated with inpatient mortality for any stroke subtype: acute ischemic stroke (OR, 1.04 [95% CI, 0.96-1.12], P=0.361), intracerebral hemorrhage (OR, 1.09 [95% CI, 1.00-1.20], P=0.052), and subarachnoid hemorrhage (OR, 1.04 [95% CI, 0.90-1.20], P=0.601).

Socioeconomic disadvantage was associated with worse outcomes in stroke among male but not female patients. These findings highlight a sex-specific disparity in stroke outcomes and underscore the need for public health initiatives targeting male patients experiencing socioeconomic disadvantage.