The Epidemiology of Hypoparathyroidism in Italy: An 8-Year Register-Based Study.

Hypoparathyroidism is a rare endocrine disorder, but few studies have focused on the epidemiology and hospital management of the disease and none has been performed in Italy. We investigated the prevalence of different forms of hypoparathyroidism among hospitalized patients in Italy during an 8-year period. This study is designed as a retrospective register-based study. We retrieved data from the "Record of Hospital Discharge" (SDO) of the Italian Health Ministry, from the year 2006 to 2013 and analyzed the codes corresponding to hypoparathyroidism-related diagnoses. The inpatient prevalence of the disease was also calculated after excluding repeated hospitalizations. Overall, 27,692 hospitalization episodes for hypoparathyroidism were identified during the entire period (72.2% in women and 27.8% in men; mean age 49.5 ± 22.9 years). The mean length of stay was 7.4 ± 9.8 days (25.9% of the episodes requiring less than 3 days of stay). The mean hospitalization rate for hypoparathyroidism was 5.9/100,000 inhabitants per year and there was a significant decrease during the period of 2006-2013 (p < 0.0001). The mean hospitalization rate for postsurgical hypoparathyroidism was 1.4/100,000 inhabitants per year and the trend showed a significant reduction during the years (p < 0.0001). The mean prevalence of hypoparathyroidism among inpatients was 5.3/100,000 inhabitants per year, and there was a significant decrease over the years (p < 0.0001). Hypoparathyroidism, particularly the postsurgical form of the disease, is not an uncommon condition among hospitalized patients in Italy. We observed a tendency to a decrease in the frequency of hospitalization during the period 2006-2013.