Evaluation of subclinical coronary atherosclerosis in mild asymptomatic primary hyperparathyroidism patients

Although there is sufficient data supporting the increased cardiovascular risk in patients with advanced stage of primary hyperparathyroidism (pHPT), it is not clear whether same is valid for patients with subclinical forms of this disease. In this study we aimed to evaluate coronary atherosclerosis burden of asymptomatic pHPT patients by using tomographic coronary calcification scoring.

Thirty-one mild asymptomatic pHPT patients (28 female, 3 male; mean age: 54.4 +/- 12.1 years) and 19 gender- and age-matched normotensive healthy controls (17 female, 2 male; mean age: 50.6 +/- 5.8) constituted our study population. Asymptomatic pHPT patients were subdivided according to presence of hypertension (19 hypertensive and 12 non-hypertensive patients). All subjects in study population underwent tomographic coronary calcification scoring by using 16-multidetector computed tomography (16-MDCT).

Median tomographic coronary calcification score was comparable between the whole group of pHPT patients [0.0 (Interquartile Range, IQR:18.70] and the controls [0.0 (IQR: 0.90). Median tomographic coronary calcification scores of pHPT patients with hypertension was 0.90 (IQR: 75.0) HU, whereas no calcification was noted in coronary arteries of normotensive pHPT patients. Calcification scores of hypertensive pHPT patients were significantly higher than both normotensive pHPT patients (P = 0.014) and controls (P = 0.046). There was no significant difference regarding calcification scores of normotensive pHPT patients versus controls. In the binary logistic regression model, only the presence of hyperlipidemia was found to be independently associated with presence of calcification on coronary arteries (relative risk 6.56, 95% CI 1.18-36.56, P = 0.032).

These results suggest that mild asymptomatic pHPT with serum calcium levels in the high-normal range does not constitute an independent risk factor for coronary atherosclerosis. The combined presence of classic cardiovascular risk factors determines the severity of coronary atherosclerosis in these patients.