Diagnostic yield of hypertension evaluation in a nephrology day hospital

Abstract

Introduction: Secondary hypertension (HTN) accounts for 5–10% of HTN. The actual diagnostic yield of a comprehensive etiological work-up in nephrology-specialized centers remains poorly documented.

Materials and methods: We conducted a single-center retrospective study including all patients evaluated in the day hospital program of the ESH-accredited Hypertension and Nephrology Unit at Rouen University Hospital for suspected secondary HTN, between 2018 and 2019. The standardized protocol combined clinical assessment, laboratory testing, imaging, and multidisciplinary discussion.

Results: One hundred patients were included. The mean age was 46.8±14.1 years; 58% were women. The main referral reasons were young age (41%), severe HTN (30%), hypokalemia (23%), and resistant HTN (22%). A secondary cause was identified in 60% of cases: primary aldosteronism (20%), kidney disease (16%), obstructive sleep apnea (12%), obesity (12%), drug-induced HTN (9%), secondary hyperaldosteronism (5%), and pseudohyperaldosteronism (3%). Essential HTN accounted for 48% of cases. Multiple diagnoses were present in 21% of cases. Hypokalemia as a motive was associated with primary aldosteronism (48% vs. 10–17% for other motives, p=0.01). Antihypertensive treatment was modified in 72% of patients with secondary HTN vs. 65% with essential HTN (p=0.53), in accordance with current guidelines at that time. An interventional or surgical treatment was performed in 6% of cases, and 83% of patients with sleep apnea were treated with continuous positive airway pressure.

Conclusion: In a nephrology-specialized ESH-accredited center, the diagnostic yield of secondary hypertension evaluation is high, with significant therapeutic implications. This supports the role of specialized nephrology centers in hypertension work-up.