Race, Changing eGFR Equations, and Risk of Stroke and Dementia

A prospective, observational study by Samuel R. Moen and colleagues assessed and compared risk of incident stroke and dementia between previous equations for estimated glomerular filtration rate (eGFR) and new, race-free equations. The study included both African American and non–African American participants.

Baseline values from 6,814 participants in the Multi-Ethnic Study of Atherosclerosis cohort were collected between 2000 and 2002, and the participants were followed up through 2018. Of that cohort, 6,646 participants were included in this analysis.

Mean (SD) participant age was 62 (10) years; 53% were women, 39% were White, 27% were African American, 12% were Chinese American, and 22% were Hispanic/Latino. Median follow-up was 17 years, during which 349 (5.3%) participants had an incident stroke event, and 574 (8.6%) participants experienced incident dementia.

The researchers used Cox proportional regression adjusting for demographic, lifestyle, and clinical variables to estimate associations between different eGFR measures and risk of incident stroke and dementia. In the fully adjusted model, participants with an eGFR of less than 60 mL/min/1.73 m² had a significantly increased risk of dementia when compared with participants with an eGFR greater than 90 mL/min/1.73 m² (hazard ratio [HR], 1.73; 95% CI, 1.21-2.45). However, a lower eGFR was not significantly associated with incident stroke (HR, 1.30; 95% CI, 0.75-2.24).

The new equations tended to reclassify African American participants to a lower eGFR group, while reclassifying non–African American participants to a higher eGFR group. However, the new and previous equations for calculating eGFR exhibited little difference regarding their association with incident stroke and dementia among both African American and non–African American participants.

In conclusion, the study demonstrated that both African American and non–African American patients with an eGFR less than 60 mL/min/1.73 m²  have a higher risk of dementia than those with an eGFR greater than 90 mL/min/1.73 m². However, the risk of stroke was not greater among patients with lower eGFR.

Source: Kidney Medicine