Clinical outcomes in patients with hypertension and renal artery stenosis across age categories

Renal artery stenosis (RAS) is a common cause of secondary hypertension (HTN) and chronic kidney disease (CKD). Studies have suggested that the prevalence of RAS increases with age. Data comparing the outcomes of RAS and concurrent HTN in different age groups is very limited. We investigated the clinical outcomes of RAS in hypertensive patients (RAS-HTN) and in different age categories.

National Inpatient Sample 2016-2020 was used to extract data with ICD-10 codes (International Classification of Diseases- Tenth Revision) for patients hospitalized with primary diagnosis of HTN and concurrent diagnosis of RAS. A multivariable logistic regression model was used to analyze the association between RAS and clinical outcomes in <30 years, 30-55 years, and >55 years age cohorts.

Among 5,647,220 nationwide admissions with primary diagnosis of HTN, a total of 39,235 were found to have RAS. Among RAS-HTN patients, 0.97% were <30 years, 11.9% were 30-55 years, and 87.13% were >55 years old. RAS-HTN was significantly associated with congestive heart failure (CHF) and pulmonary edema among all age groups. RAS-HTN had the strongest association with CHF in >55 years cohort (OR 4.89, CI 4.62-5.16, p < 0.001), followed by 30-55 (OR 3.56, CI 3.06-4.1, p < 0.001) and <30 (OR 3.45, CI 1.78-6.73, p < 0.001) years cohorts. RAS-HTN had strongest association with pulmonary edema in <30 years cohort (OR 3.82, CI 1.1-13.3, p = 0.035) followed by >55 (OR 1.87, CI 1.57-2.2, p ≤ 0.001) and 30-55 (OR 1.74, CI 1.09-2.78, p = 0.02) years cohorts. Furthermore, RAS-HTN had significant association with ischemic heart disease (IHD) and arrhythmia in >55 years cohort (OR 2.73, CI 2.59-2.89, p < 0.001 vs OR 1.26, CI 1.19-1.33, p < 0.001 respectively) and 30-55 years cohort (OR 2.35, CI 2-2.74. p < 0.001 vs OR 1.27, CI 1.04-1.55, p = 0.017 respectively). There was no association observed for RAS-HTN with IHD and arrhythmia in the <30 years cohort.

The proportion of patients with RAS-HTN increased with increasing age and 11.9% were between 30 and 55 years. The observed stronger association of increased CHF and pulmonary edema in patients < 30 years of age emphasizes the need for early screening for RAS in patients with resistant hypertension in this age group.