Increasing incidence of primary hyperparathyroidism in Denmark

Abstract

Introduction: Primary hyperparathyroidism is a common endocrine disorder with different epidemiological patterns among countries. In Denmark, the incidence of primary hyperparathyroidism was last described in 1999 when it was reported to follow an increasing trend. In the present study, we evaluated trends in the incidence of primary hyperparathyroidism in Denmark up to 2010.

Material and methods: All patients diagnosed with primary hyperparathyroidism from 1977 to 2010 were included. Annual incidence rates were calculated.

Results: The overall incidence was clearly increased at the end of 2010 with an annual rate of 16 per 100,000. Following a cyclic curve, year-to-year incidence rates were fluctuating. During the entire period, the incidence was higher in women than in men. Furthermore, in women above the age of 50 years, a five-fold increase in incidence was observed, while there was no difference in the increase among men above the age of 50 years compared with men under the age of 50 years.

Conclusion: The incidence of primary hyperparathyroidism in Denmark continues its remarkable rise. The overall increase in incidence may be the result of more frequent plasma calcium measurements as well as the prevailing obesity epidemic. The dramatic increase in incidence observed among women over the age of 50 years requires further studies. The causes of the cyclic trend observed are uncertain, as no seasonal variation was seen.

Funding: not relevant.

Trial registration: not relevant.