Effect of Steroid Replacement on Long-Term Kidney Function in Patients With Adrenal Insufficiency

Objective The prevalence of adrenal insufficiency (AI) is increasing with an increase in the elderly population. Steroid replacement therapy (SRT) is often required in patients with AI because of acute symptoms and complications. The long-term effects of SRT on kidney function have not been well elucidated. Methods Overall, 788 patients diagnosed with AI between 2010 and 2015 at Yonsei University Health System were retrospectively evaluated. SRT was defined when an equivalent dose of ≥5 mg/d of hydrocortisone was initiated within 30 days of AI diagnosis and maintained for >30 days. Those not included in the SRT group were identified as the no-SRT group. The primary outcome was 40% reduction in the estimated glomerular filtration rate compared with baseline sustained for ≥30 days or end-stage kidney disease development. Results The mean age of was 63.1 ± 15.4 years, and 43.0% were men. The SRT group comprised 387 patients. During a median follow-up duration of 4.1 years, the primary outcome occurred in 118 (15.0%) patients. The outcome incidence rate was higher in the SRT group (4.61/100 patient-years) than in the no-SRT group (2.76/100 patient-years). When the subdistribution hazard ratio for kidney outcome was assessed with death as a competing risk, the risk was 67% higher in the SRT group than in the no-SRT group (subdistribution hazard ratio, 1.67; 95% confidence interval, 1.16-2.45; P = .006). This association was maintained with inverse probability of treatment weighting and adjustment for confounding variables. Conclusion Kidney function decline was more prominent in patients with AI who received SRT. Further prospective evaluations are needed to confirm these findings.