This study uses data from the Nurses’ Health Study I to investigate whether calcium intake contributes to the risk of primary hyperparathyroidism in female patients.
During the course of the follow up, 277 women were diagnosed with primary hyperparathyroidism. When their calcium intake was analyzed, women who had the highest intake (median of 1070, mg per day) had a reduced risk of developing primary hyperparathyroidism. Compared to women who had the lowest calcium intake (443 mg per day), their relative risk was 0.48 (95% Confidence Interval 0.33–0.69, Ptrend<0.001) and their multivariable risk was 0.41 (95% CI 0.27–0.63, Ptrend<0.001).
The impact of calcium supplements was also assessed; women taking calcium supplements of at least 500 mg per day also had a significantly reduced risk of primary hyperparathyroidism. Women taking this dose compared with women taking no calcium supplements had a relative risk of 0.69 (95% CI 0.50–0.94, Ptrend<0.001).
Editor’s comment: In these days of great controversy about the benefits and risks of calcium supplements, this observational study provides arguments in favor of using calcium supplements to decrease the risk of developing primary hyperparathyroidism.