Endocrine Abstracts

Introduction: Dyslipidemia is a common finding in patients with primary hyperparathyroidism and together with hypertension and glucose intolerance seems to be responsible by the increased risk of cardiovascular disease in hyperparathyroid patients. In the present work we studied members of a family harboring a MEN1 gene mutation (type 1 multiple endocrine neoplasia syndrome). The penetrance of primary hyperparathyroidism in this condition is close to 100%, starting usually during the second decade of life.

Objective: To study the evolution of carbohydrate and lipid metabolism with the onset of primary hyperparathyroidism as well as with parathyroidectomy.

Patients and methods: All patients enrolled in the present study belong to the same family harboring a new MEN1 gene mutation located in the exon 2 (c124G>C), which leads to substitution of glycine by arginine (Gly42Arg). Three patients with symptomatic hyperparathyroidism exhibited severe combined dyslipidemia. Five young members without clinical and laboratorial evidence of the disease were followed at regular time intervals. Results are presented as the mean±S.D. of three consecutive determinations in each patient.

Results: Parathyroidectomy was followed by an immediate decline in total cholesterol (from 251±46 to 225±27 mg/dl) as well as in triglycerides (from 465±129 to 238±65 mg/dl). Fasting glycemia returned to values of <100 mg/dl. In young asymptomatic family members, the onset of hyperparathyroidism was closely followed by a twofold increase in insulinemia (from 9±6 to 21±7 mU/l) and in triglycerides (from 85±12 to 167±37 mg/dl), together with a decline of HDL cholesterol (from 67±9 to 52±5 mg/dl). None of these alterations was detected in non-affected family members.

Conclusion: In addition to normalization of serum calcium and PTH, parathyroidectomy corrected, at least partially, alterations in serum lipids as well as in the metabolism of carbohydrates. In previously asymptomatic patients, the onset of primary hyperparathyroidism was associated with an increase in insulin resistance and with the development of a more atherogenic lipid profile.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.