Middle-aged adults with orthostatic hypotension experience greater kidney function decline than those without the condition, a new study finds.
Among 5905 adults aged 40-69 years in the Korean Genome and Epidemiology Study, 268 (4.5%) experienced classic orthostatic hypotension, defined as a drop in systolic blood pressure of 20 mm Hg or more or a drop in diastolic blood pressure of 10 mm Hg or more at 2 minutes after standing.
Over 12 years, estimated glomerular filtration rate (eGFR) declined at a faster rate (a beta coefficient of -1.74) in adults with than without classic orthostatic hypotension, Yu-Ji Lee, MD, PhD, and colleagues from Samsung Changwon Hospital, Sungkyunkwan University School of Medicine in Changwon, Republic of Korea, reported in Nephron. Classic orthostatic hypotension was significantly associated with a 27% increased risk of a 30% decline in kidney function in a fully adjusted model.
The investigators adjusted models for age, sex, comorbidities (eg, diabetes, hypertension, etc), antihypertensive drugs, body mass index, smoking, systolic blood pressure, diastolic blood pressure, eGFR, fasting blood glucose, cholesterol, hemoglobin, serum albumin, and albuminuria.
The initial hypotension episode was not solely responsible for kidney decline. The investigators suggested several plausible mechanisms. Orthostatic hypotension may decrease renal perfusion and intraglomerular pressure, resulting in kidney damage. Patients with the condition may experience greater blood pressure variability and supine hypertension linked to organ damage. In this study, a significantly greater proportion of those with and without orthostatic hypotension had supine hypertension (26.1% vs 11.7%). Lastly, autonomic dysfunction linked with the condition may contribute to kidney dysfunction.
According to Dr Lee’s team, “the assessment of classic OH is worth considering as a predictor of kidney dysfunction.”
Na JH, Kim SR, Lee YJ. Effect of orthostatic hypotension on kidney function. Nephron. Published online January 17, 2023. doi:10.1159/000528431