Primary hyperparathyroidism predicts hypertension: Results from the National Inpatient Sample.

INTRODUCTION: Primary hyperparathyroidism (pHPT), most commonly caused by solitary parathyroid adenomas, leads to mobilization of calcium and is known to result in nephrolithiasis and osteoporosis. To date, studies of pHPT and cardiovascular risk factors and events have produced discrepant findings, likely due to small sample sizes and enrolling populations with varying disease severity.

HYPOTHESIS: We utilized a national registry, hypothesizing an association between pHPT and cardiovascular risk factors and events.

METHODS: Patients >18years with a diagnosis of pHPT were identified in the Nationwide Inpatient Sample 2009-2010 database using the Ninth Revision of International Classification of Diseases code 252.01. Demographics, risk factors, and cardiovascular event rates were collected and compared to general population data.

RESULTS: pHPT was present in 0.1% (n=37,922) of hospital admissions. There was a significant increase in the prevalence of most cardiac risk factors including hypertension (HTN), diabetes mellitus, hyperlipidemia, obesity, and chronic kidney disease. The rates of heart failure (HF) and coronary artery disease (CAD) were higher in the pHPT population. However, after performing multivariate regression for age and cardiac risk factors, pHPT did not independently predict HF or CAD. The risk of HTN, however, was independently predicted by pHPT (OR 1.3; p<0.001).

CONCLUSIONS: Primary hyperparathyroidism independently predicted the risk of hypertension in a patient population from a large national database. Despite significant differences in univariate analysis of cardiac risk factors and events, pHPT did not independently predict risk of HF or CAD after multivariate regression analysis. Future studies should explore potential mechanisms relating hypertension to pHPT.