Primary hyperparathyroidism incidence in northeastern Italy: A large population-based study

Population-based studies of trends in the incidence of primary hyperparathyroidism (PHPT) in Italy were still lacking. Our aim was to estimate the incidence of PHPT in the Veneto region over the period 2012–2023. A retrospective, population-based study conducted in Veneto using the population registry and administrative health databases. Only subjects ≥ 18 years of age were included. We documented incident PHPT from 2013 to 2023 to exclude prevalent cases and calculated standardised incidence rates (IR) per 10,000 person-years by age and sex. We also made a sub analysis of only surgical cases. We identified 5,276 incident cases (IR: 1.17). Overall, the incidence of PHPT was stable from 2013 to 2023, although there was a declining trend in males, at the limits of statistical significance with the standardised IR decreasing from 0.77 (95% CI: 0.64;0.91) in 2013 to 0.67 in 2023 (95% CI: 0.55;0.78) (p = 0.056). The overall female-to-male incidence ratio was 2.55, with females predominating, and reached a peak in the 50–54 age group (ratio: 3.94) and a nadir in 25–29 age group (ratio: 0.54). Median age was 65 years (IQR: 56–76 years) and was lower among females than males (64 vs 68 years) (p < 0.0001). Among the surgical cases, the percentage distribution of incident cases by age was almost the same for females and males, median age was similar (61 years for females, 62 years for males), while the rates remained higher for females than for males. Our study shows that over the past decade there has been a general stability in the incidence of PHPT in our Region. A higher incidence was observed in postmenopausal females and a different pattern of incidence emerged from our analysis of surgical cases.