Anthropometric Indices and Markers of Atherothrombotic Risk in Subjects with Primary Hyperparathyroidism

Background: Both primary hyperparathyroidism (PHPT) and chronic hypoparathyroidism (HypoPT) are associated with the onset and development of cardiovascular diseases (CVDs). In particular, PHPT is accompanied by the presence of elevated atherothrombotic risk, while the importance of traditional and new anthropometric indices to reflect the cardiovascular risk remains uncertain in this condition. This study aims to investigate whether novel and traditional anthropometric indices distinguish PHPT and whether these indices are correlated with atherothrombotic risk. Methods: A total of 40 subjects with HypoPT, 40 with PHPT and 40 age- and sex-matched control subjects were consecutively enrolled for the evaluation of flow-mediated vasodilation (FMD) and carotid intima-media thickness (IMT). A blood sample was collected for evaluation of calcium-phosphate metabolism, PTH, TSH and 25-hydroxy vitamin D. Physical examination was performed to obtain traditional anthropometric parameters and derived indices of adiposity and cardiometabolic risk (waist-to-height ratio (WHtR), waist-to-hip ratio (WHR) and conicity index (CI)). Results: The PHPT group showed higher central adiposity indices (WHtR p = 0.002, and CI p = 0.008). Among patients with parathyroid disorders, PHPT subjects displayed the highest reduction in FMD (p < 0.001) and a marked increase in IMT (p < 0.001). In the Ctrl group, WHtR showed a weak-to-moderate positive association with IMT (r = 0.381, p = 0.018). In the PHPT group, no anthropometric index was significantly correlated with IMT or FMD (all p > 0.05). Conclusions: WHtR and CI provide evidence of increased central fat adiposity in PHPT but do not account for impaired atherothrombotic risk, indicating that anthropometric indices may lack relevance to cardiovascular risk in this condition and emphasizing the importance of a specific assessment profile.