Epidemiology of chronic hypoparathyroidism in Italy: a systematic review and meta-analysis

Hypoparathyroidism (HPT) is an endocrine disease caused by insufficient levels of parathyroid hormone (PTH). PTH is the primary regulator of the calcium/phosphate balance, acting directly on bone and kidney, and indirectly on the intestine. Regarding the epidemiology of chronic HPT, there are limited data in Italy. This study aimed to establish incidence and prevalence of chronic HPT in Italy. A systematic literature review was conducted to identify the current knowledge regarding the epidemiology of chronic HPT in Italy, and a random effect meta-analysis was performed to estimate the pooled incidence. A subgroup analysis of non-surgical and postsurgical HPT estimates for patients was also conducted. We identified 4 studies eligible for inclusion reporting data from 15,412 patients with HPT. Considering a thyroidectomy rate of 57 per 100,000 and the incidence of post-surgical chronic HPT (≥ 6 months after surgery) at 1.2% (95% CI: 0.7%-1.8%), the number of incident post-surgical chronic HPT was estimated in 353 cases. Based on a mean time with chronic HPT after diagnosis of 17.4 years, a total of 6,142 prevalent post-surgical chronic HPT patients has been estimated for Italy. Findings from this analysis showed 4,383 prevalent non-surgical chronic HPT cases in Italy. The prevalence of chronic HPT, both surgical and non-surgical, in the adult population in Italy has been estimated to be 10,524 cases. This study provides a current estimate of the prevalence and incidence of chronic HPT in Italy. In this analysis, postsurgical chronic HPT accounted for the majority of prevalent cases. Epidemiological studies with appropriate study design are necessary to provide a validated estimation of the prevalence and incidence of HPT in Italy.