Risk of Fracture in Primary Aldosteronism: A Population-Based Cohort Study

Primary aldosteronism (PA) is associated with increased urinary calcium excretion and osteoporosis prevalence. We studied the long-term effect of hyperaldosterone on fracture risk and possible risk mitigation via treatments, by comparing PA patients and their essential hypertension (EH) counterparts extracted by propensity score match. We used a longitudinal population database from the Taiwan National Health Insurance, and used a validated algorithm to identify PA patients diagnosed in 1997-2010. Our sample included 2533 PA patients, including 921 patients with aldosterone-producing adenoma (APA). Our methods for assessing excessive fracture risk included multivariable Cox regression and the competing risk regression. The incidence rate of fracture at any site was 14.4 per 1000 person-years for PA, and 11.2 per 1000 person-years for APA. In contrast, the incidence rate of fracture at any site was 8.3 per 1000 person-years in EH controls for PA, and 6.5 per 1000 person-years in EH controls for APA. Mineralocorticoid receptor antagonist (MRA) treatment might be associated with higher risk of osteoporotic fracture in the whole female PA cohort (subdistribution hazard ratio [SHR]=2.12, p=0.008) as well as female APA patients (SHR=1.15, p=0.049). As to fracture at any site, MRA treatment was also associated with higher risk; the SHR was 1.88 (p < 0.001) in the whole female PA cohort, and 2.17 (p=0.019) in female APA patients. PA is tightly associated with higher risk of bone fracture, even in the case where the competing risk of death was controlled. Particularly, female PA patients treated with MRA were confronted with significantly higher risk in bone fracture than their EH controls. (c) 2017 American Society for Bone and Mineral Research.