Effect of gender and geographic location on the expression of primary hyperparathyroidism

Background: The effect of gender on the expression of primary hyperparathyroidism (PHPT) is not well characterized. Aim: We therefore evaluated two Caucasian populations (US and Italian) of men and women with PHPT, matched for age and body mass index (BMI), in a cross-sectional retrospective observational study. Methods: We studied 74 US (23 men) and 126 Italian (42 men) patients evaluating main biochemical indices of the disease and bone mineral density (BMD) at the spine and proximal femur. Results: Mean serum calcium levels were higher both in Italian men compared to women (11.7 +/- 1.22 mg/dl and 11.1 +/- 0.83, p<0.01) and in Italian compared to US patients (11.3 +/- 1.01 and 10.8 +/- 0.58, p<0.001), with similar results for the serum ionized calcium. Mean serum PTH levels were not different either between the genders or between the countries. After controlling for BMI, the mean BMD at both the femoral neck and total hip in females US patients was significantly higher compared with Italian female patients. Conclusion: Despite similar levels of circulating PTH, Italian patients have more pronounced effects of the disease as assessed by serum calcium and a more significant cortical involvement in women as assessed by BMD. (C)2013, Editrice Kurtis