Area-Level Income Disparities and the Timing of First Ischemic Stroke: Insights From the 2019 National Inpatient...

Socioeconomic status plays a crucial role in determining health outcomes, particularly the age at which individuals experience their first ischemic stroke. This study investigates the relationship between ZIP-code level median income and the age at the first ischemic stroke, considering various demographic and clinical characteristics.

We identified patients >18 years old from the 2019 National Inpatient Sample database with a primary diagnosis of ischemic stroke. Multivariate linear regression adjusted for sex, race, patient location, and comorbidities was used to estimate the impact of income on the age at the first ischemic stroke.

Among 94 074 patients, representing a national estimate of 470 370, the mean age at first stroke was 70.1±13.9 years, with 49.5% women. In the lowest (<$47 999) area-level income group, the average age of the first stroke was 4.3 years lower than the highest ($82 000+) income group (68.1±13.8 versus 72.4±13.8). After adjusting for sociodemographic factors and comorbidities, the highest-income individuals were 2.1 years older (95% CI, 2.3-2.5) at first ischemic stroke compared with those in the lowest-income category. Area-level income disparities also affected stroke age across racial groups and sexes. Specifically, first stroke occurred 2.6, 0.9, and 0.9 years earlier for White, Black, and Hispanic individuals, respectively. Women experienced a 2.3-year delay compared with a 1.9-year delay for men.

Lower income levels are associated with the first incidence of stroke at a younger age, especially among White individuals and women, highlighting socioeconomic status-related disparities in stroke incidence. Further studies to investigate the underlying factors are warranted.