Gender differences in the presentation, course and outcomes of primary hyperparathyroidism.

Objective: To investigate gender-associated differences in the presentation, course, and outcomes of primary hyperparathyroidism (PHPT).

Study Design: A retrospective institutional cohort.

Methods: The database of a tertiary endocrine institute was retrospectively screened for patients treated for PHPT in 2010-2018. Clinical, biochemical, and imaging data were collected. Presentation, management, and outcome variables were compared by gender and by age at diagnosis (<50/≥50 years).

Results: The cohort included 182 women and 161 men diagnosed with PHPT at age 57.6 ± 12.8 and followed for 6.3 ± 5.5 years. There were no gender differences in age at detection of hypercalcemia and basal levels of serum and urinary calcium, serum PTH, and serum 25-hydroxyvitamin D. Men had a higher prevalence of nephrolithiasis (33 % vs 21 %, p = 0.01). Women had a higher frequency of osteoporosis (65 % vs 45 %, p < 0.001), and a lower mean lumbar spine T-score at PHPT diagnosis. At last follow-up, women had worse bone mineral density (BMD) results in all measured sites (lumbar spine, femoral neck, distal radius) and more fractures (34 % vs 20 %, p = 0.004), despite more frequent and longer pharmacological treatment of osteoporosis. On analysis by age, all these gender-associated differences were statistically significant only in patients diagnosed at age ≥50 years. Parathyroidectomy was performed in 52 % of women and 42 % of men (p = 0.06).

Conclusion: The main differences between male and female patients with PHPT are the higher prevalence, more intensive pharmacological treatment, and worse outcomes of osteoporosis in women. Tailoring the optimal medical and/or surgical treatment for fracture prevention in patients with PHPT remains a major challenge, especially in older women.