Endocrine Abstracts

Objective: Vitamin D deficiency is frequently encountered in patients with primary hyperparathyroidism (PHPT), a condition characterised by excessive parathyroid hormone (PTH) secretion and hypercalcemia. This systematic literature review and meta-analysis aimed to assess the management of vitamin D deficiency in PHPT by evaluating vitamin D supplementation regimens and their impact on vitamin D and PTH levels and calcium levels.

Methods: A comprehensive search of electronic databases, including Embase and Pubmed, was conducted to identify relevant studies. Inclusion criteria were predefined in select studies focusing on native vitamin D supplementation in patients with PHPT and reporting data on vitamin D, PTH, and calcium levels. A qualitative and quantitative data synthesis was performed using Review Manager 5.43 software, and a random effect model was employed to analyse pooled data.

Results: A total of 11 studies involving 434 patients met the inclusion criteria. The meta-analysis demonstrated a significant increase in vitamin D levels following vitamin D supplementation (Z = 5.0, P< 0.00001), indicating the efficacy of various regimens in addressing vitamin D deficiency in PHPT patients. Moreover, a significant reduction in PTH levels was observed after vitamin D supplementation (Z = 2.88, P= 0.004), suggesting its potential to modulate PTH secretion and improve calcium homeostasis. Our analysis also revealed a significant reduction in calcium levels with vitamin D supplementation (Z = 2.86, P 0.004), indicating its favourable effect on hypercalcemia associated with PHPT.

Conclusion: This systematic literature review and meta-analysis provide evidence supporting the positive impact of vitamin D supplementation on vitamin D and PTH levels in patients with PHPT. Additionally, our findings highlight its favourable effect on calcium levels, an aspect not extensively explored in previous meta-analyses. However, heterogeneity across studies and limitations in data availability necessitate cautious interpretation of the findings.