Endocrine Abstracts

Objective: The clinical presentation of primary hyperparathyroidism (PHPT) has changed dramatically over the last three decades. Previous epidemiological estimations of PHPT are mainly derived from highly selected populations. This paper systematically evaluates the prevalence and incidence of PHPT in Tayside, Scotland, using a real-world unselected population base.

Methods: All Tayside residents with an increased serum calcium concentration (>2.55 mmol/l) between 1997 and 2006 were included as potential participants. Using a unique patient identifier, data-linkage enabled a dataset of PHPT patients to be created from an algorithm of biochemistry records, nuclear scan records, histology records, hospital admission data and clinic letters. Persons having tertiary hyperparathyroidism (14%) were identified and excluded. Year-on-year age and sex adjusted incidence density and period prevalence were calculated. The trend of patients’ biochemical profile was also evaluated.

Results: We identified 2761 patients (70.4% female) diagnosed with PHPT. The mean age of women (67 S.D.=16) was older than that of men (62 S.D.=18) at baseline. The prevalence of PHPT in Tayside increased from 1.41 per 1000 population in 1997–5.28 in 2006 (P<0.001). Prevalence of PHPT is higher in females, and the female preponderance increases with age; the annual prevalence ratio between women and men is stable at around 2.5 each year. There was a 3-4-year cyclical incidence rate varying from 3.18 to 8.82 per 10 000 person-years.

Conclusion: We observed a general increase in the prevalence of PHPT in Tayside, Scotland. The incidence is greater in females and increases with age. The annual incidence followed an apparent cyclic curve during the study period and suggests further analysis study would be worthwhile.