Incident Hypertension in Young Adults With a Mild Estimated Glomerular Filtration Rate Reduction

Hypertension is a common, modifiable risk factor for cardiovascular disease with an increasing occurrence in young adults. We examined the association of lower-than-normal kidney function with incident hypertension in young adults (aged 18-39 years) compared with middle-aged (aged 40-49 years) and older adults (aged 50-65 years).

We conducted a historical cohort study of 7.8 million individuals (3.7 million aged 18-39 years) using linked provincial health care data sets from Ontario, Canada, between 2008 and 2021. Cox models were used to examine the association of categorized estimated glomerular filtration rate (eGFR) (60-100 mL/min per 1.73 m²) and incident hypertension, stratified by age (18-39, 40-49, and 50-65 years).

Among our cohort (mean age, 40.4 years; mean eGFR, 104.9 mL/min), a total of 170 905 (4.6%) individuals developed hypertension among young adults, compared with 279 937 (15.3%) in those aged 40 to 49 years and 588 195 (25.2%) in those aged 50 to 65 years. The adjusted rates of hypertension increased with an eGFR of <100 mL/min, increasing step wise as eGFR declined, and occurred at a higher relative eGFR in young adults compared with older age groups. Among young adults who developed hypertension, cardiovascular events were 6- to 10-fold more common and were more likely with minor eGFR reductions.

Minor reductions in eGFR in younger adults are associated with new-onset hypertension and a higher risk of cardiovascular consequences, suggesting early identification, monitoring, and management may be beneficial.