Endocrine Abstracts

Introduction: Multiple adverse health outcomes are reported in response to low vitamin D and/or hyperparathyroidism.

Aim and methods: A cross-sectional study in a random sample of mainly non-vitamin D supplemented Danish women (N=1580) during winter-time. We investigated prevalence of vitamin D insufficiency, hyperparathyroidism, general health and quality of life (QoL) as assessed by a general health questionnaire and a validated hyperparathyroidism health-related quality of life questionnaire prior to blood sampling.

Results: Plasma PTH and 25(OH)D were inverse associated. In the total cohort, median 25(OH)D was 66 [50 to 83] nmol/l and PTH 5.2 [4.2 to 6.6] pmol/l. The prevalence of P-25(OH)D <50 and <25 nmol/l was 23.9% (N=376) and 2.8% (N=44), respectively. The prevalence of mild primary- (PHPT) and secondary hyperparathyroidism was 2.9% (N=46) and 6.9% (N=109) respectively. General health or QoL did not differ between women with normal biochemical findings and those with low 25(OH)D levels and/or SHPT. In 64% (N=29) of the 46 women with initial biochemical findings consistent with PHPT, the diagnosis was validated by consecutive measures of PTH and ionized-calcium. Among those, half (N=14) had a parathyroidectomy performed due to complications associated with the disease, including vertebral fractures (X-ray), low BMD (DXA) or renal calcifications (CT-scan). Women with PHPT complained more often of nocturia and had more often a history of kidney disease, whereas QoL did not differ from healthy women.

Discussion: Low 25(OH)D levels are prevalent during wintertime in Denmark, whereas elevated PTH levels occurs with a lower frequency. By itself, low 25(OH)D and/or high PTH levels are not associated with adverse health outcomes, as long as calcium are normal. However, even mild PHPT was associated with known complications to the disease.