Insulin resistance and androgen levels in eugonadic and hypogonadic women with prolactinoma

BACKGROUND

Hyperprolactinemia is the most common endocrinologic disorder in causing menstrual irregularities. Although the correlation between hyperprolactinemia and menstrual dysfunction is widely known, the etiology of menstrual cycle disorders is not profoundly understood in patients with prolactinoma. We aimed to investigate the correlation between prolactin levels and insulin resistance and hyperandrogenism in patients with prolactinoma.

METHODS

Sixty-four patients with microprolactinoma and 33 healthy women were enrolled. Thirty-six of these patients with prolactinoma (group 1) had an estradiol (E2) level under 30 pg/mL, and 28 (group 2) had an E2 level greater than 30 pg/mL. Blood samples were drawn to measure the levels of the following hormones: Follicle stimulating hormone (FSH), luteinizing hormone (LH), E2, prolactin (PRL), total testosterone (TT), androstenedione (AS) and dehydroepiandrostenedione sulphate (DHEAS). Body Mass Index (BMI of ≥30 kg/m2) was excluded from the study. Insulin resistance (IR) was calculated by the HOMA-IR.

RESULTS

BMI was higher in patients with prolactinoma than the control group (P=0.02, P=0.025, respectively). IR and glucose intolerance existence were higher in patients with prolactinoma (P=0.007, P=0.097, respectively) than the healthy women, but these differences did not exist between eugonadic and hypogonadic women with prolactinoma (P=0.020, P=0.032, respectively, Bonferroni correction). TT and AS were higher in eugonadic women with prolactinoma than the control group (P=0.004, P=0.003, Bonferroni correction, respectively).

CONCLUSIONS

Our study revealed that the relationship between hyperprolactinemia and IR/glucose intolerance is irrespective of gonadal status in women with prolactinoma. Also, the study concluded that hyperandrogenism may be a cause of menstrual dysfunction in eugonadic women with prolactinoma.

Impaired endothelial function in patients with mild primary hyperparathyroidism improves after parathyroidectomy

BACKGROUND

Primary hyperparathyroidism (PHPT) is associated with cardiovascular morbidity; however, data on the reversibility of cardiovascular disease in mild primary hyperparathyroidism are conflicting. The aim of this study was to assess endothelial function in patients with mild PHPT before and after parathyroidectomy (Ptx).

METHODS

We prospectively evaluated 53 patients with mild PHPT (Group 1; 45 women, eight men; aged 52 ± 3·1 years) and 46 healthy control subjects (Group 2; 38 women, eight men; aged 46 ± 9·5 years). Endothelial function was measured as flow-mediated dilation (FMD) and carotid intima-media thickness (CIMT) using Doppler ultrasonography. Patients with diabetes mellitus, coronary heart disease, impaired renal function, hyperthyroidism, hypothyroidism and a history of smoking were excluded from the study. Patients were studied at baseline and 6-12 months after the first evaluation.

RESULTS

There were no differences with respect to age, gender and BMI between the two groups. Hypertension prevalence was three times higher in group 1 than in controls. % FMD was lower in group 1 than in group 2 (2·6 ± 1·2 vs 14·8 ± 9·6, P < 0·001). CIMT was higher in patients with PHPT than controls (0·69 ± 0·18 vs 0·61 ± 0·12, P = 0·045). This significance remained when hypertensive patients were excluded from the analysis. While FMD and CIMT improved significantly after Ptx, there were no differences in mild PHPT patients who followed without parathyroidectomy.

CONCLUSION

FMD and CIMT are impaired in patients with mild PHPT compared to controls and improved significantly after a successful Ptx. Ptx improves endothelial function in patients with mild PHPT that may lead to decreased cardiovascular morbidity and mortality.

Increased Risk of Unfavorable Metabolic Outcome in Patients with Clinically Nonfunctioning Pituitary Adenomas

The aim of this study was to investigate atherosclerotic risk markers in women with clinically nonfunctioning pituitary adenomas (CNFAs). Records of 47 women with CNFAs and 73 healthy women who were treated as outpatients between January 2010 and March 2014 were evaluated retrospectively. All study data were obtained from file records. Lipid parameters, mean platelet volume (MPV), total testosterone (TT), androstenedione (AS), and dehydroepiandrostenedione sulfate (DHEAS) were recorded. Insulin resistance (IR) was calculated with homeostatic model assessment-insulin resistance (HOMA-IR). Among the atherosclerotic risk markers, the HOMA-IR and AS levels were higher in patients with CNFAs than in healthy subjects (p=0.003, p=0.021, respectively). A positive correlation between AS and insulin/HOMA-IR levels was found among the metabolic parameters in the patients with CNFAs (p=0.001, r=0.550, p=0.004, r=0.498, respectively). The data showed that patients with CNFAs had high atherosclerotic risk markers such as insulin resistance and hyperandrogenemia. Insulin resistance may also cause hyperandrogenemia in patients with CNFAs.

Characterization of V804M-mutated RET proto-oncogene associated with familial medullary thyroid cancer, report of the largest Turkish family

PURPOSE

Analysis of the RET proto-oncogen is very important for diagnosis and prognosis of medullary thyroid cancer (MTC). Genotype-phenotype correlation is also well known. Here we report features of the largest known family in Turkey with the V804M-mutated RET proto-oncogene.

METHODS

Thirty members from three generations were evaluated. A RET proto-oncogen mutation, calcitonin (Ct) measurement and thyroid ultrasound were performed on all individuals. Seventeen members had V804M mutation. Fourteen of these patients underwent total thyroidectomy and additional central lymph node dissection for five subjects.

RESULTS

The mean age of patients with MTC was 46.5 (30-61) years. The mean calcitonin level of RET positive members was 13.27 pg/mL (1-49.8 pg/mL). Three had a basal Ct level above normal limits. Seven of the 14 patients were diagnosed with MTC, and two were diagnosed with papillary thyroid cancer without MTC. One patient had central neck metastasis. Hyperparathyroidism or pheochromocytoma was not detected in any case. Patients who were RET negative, had normal Ct levels and no suspected nodule on ultrasound examination.

CONCLUSIONS

Our study revealed a relatively good prognosis in patients with V804M mutation. Despite the surgery was performed in older age no advance disease was observed.