Body fat distribution by anthropometric and MRI-based techniques in relation to insulin secretion and action in men with diabetes.

AIM: Differences in fat accumulation and distribution might be responsible for the greater insulin resistance (IR) in type 2 diabetes. The study aims at examining the relationship between fat accumulation and distribution, and insulin secretion and action, by multilevel methodological approach. METHODS: Thirty-three diabetic men (D), and 28 sex, age and BMI-matched controls (C) were studied for glucose and insulin during OGTT, insulin resistance and sensitivity, employing HOMA and Matsuda index respectively, and, fat accumulation and distribution by anthropometrics, Bioimpendance Analysis (BIA), and multiple slices MRI of abdomen and hip. RESULTS: D exhibited higher HOMA compared to C (P<0.001), and lower Matsuda index (P=0.062). No differences in fat distribution by anthropometric or MRI measurements were observed; however, fat accumulation by BIA was higher in D (P=0.035). HOMA correlated to basal, AUC, and peak insulin in both groups (all P<0.001); with weight (r=0.415, P=0.031), hip circumference (HC) (r=0.482, P=0.011), %fat (r=0.400, P<0.05) in C; and with weight, BMI, total and %fat, and waist and HC when all subjects were considered as a group. Matsuda inversely correlated with basal, AUC, and peak insulin (all P<0.001), and HC (r=-0.406, P=0.032) in C. HOMA strongest correlated with L3-L4 subcutaneous (r=0.551, P=0.003) in C, and with L3-L4 visceral (r=0.456, P=0.022) in D. CONCLUSION: The greater IR in diabetic patients may not be interpreted by differences in fat distribution. IR correlates with different fat compartments in healthy and diabetic subjects of comparable fat distribution, suggesting differences in fat function.

The effect of L-thyroxine substitution on lipid profile, glucose homeostasis, inflammation and coagulation in patients with subclinical hypothyroidism.

AIMS: Subclinical hypothyroidism (SH) is associated with increased risk for atherosclerosis, mainly attributable to dyslipidaemia and hypercoagulability. However, conflicting data exist regarding the effect of L-thyroxine substitution on these parameters. The purpose of this study was to assess the effect of L-thyroxine therapy on lipidaemic profile, coagulation markers, high-sensitivity C-reactive protein (hsCRP) and glucose homoeostasis in SH patients. METHODS: It was a prospective open-label study. The following parameters were measured before and 6 months after intervention: anthropometric data, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), apolipoproteins B (apoB) and A1 (apoA1), lipoprotein (a) [Lp(a)], fasting plasma glucose and insulin, homoeostasis model assessment-insulin resistance (HOMA-IR), hsCRP, antithrombin III (AT-III), protein C (PC), protein S (PS), fibrinogen and homocysteine. RESULTS: Thirty-two patients (30 women) aged 52.1 ± 13.9 years with SH completed the study. Baseline mean TSH levels were 6.79 ± 2.58 mIU/ml. Achievement of euthyroidism significantly reduced systolic blood pressure (BP) in patients with SH (from 135.2 ± 18.5 to 129.7 ± 15.8 mmHg, p = 0.03) and diastolic BP only in those with baseline TSH levels > 7 mIU/ml (from 79.5 ± 9.8 to 72.1 ± 7.3 mmHg, p = 0.03). No significant changes in body weight, TC, LDL-C, HDL-C, TG, apoB, glucose, insulin, HOMA-IR, hsCRP, AT-III, PC, PS, fibrinogen or homocysteine levels were noticed after restoration of euthyroidism, except for a decrease in apoA1 (p = 0.04) and an increase in Lp(a) levels (p = 0.02). CONCLUSIONS: Except for a reduction in systolic and diastolic BP, thyroid substitution therapy does not affect lipidaemic profile, systematic inflammation, glucose homoeostasis or coagulation in patients with SH.

Acromegaly: presentation, morbidity and treatment outcomes at a single centre.

OBJECTIVE: Analysis of patients with acromegaly followed-up at a single centre, focusing on baseline characteristics, morbidity and efficacy of treatment. DESIGN AND METHODS: Retrospective review of electronic medical records of acromegalics from 1987 to 2009. RESULTS: One hundred and fifteen patients (45 men), aged 47 ± 14 years, with a mean follow-up of 8.8 ± 0.8 years were studied. Twenty-five per cent had micro- and 75% macroadenomas. Forty-three per cent presented with visual field defects, 49% had hypertension, 25% diabetes mellitus and 35% dyslipidaemia. At follow-up, 50% had myocardial hypertrophy, 55% colon polypodiasis, 74% nodular thyroid disease and 18% adrenal masses. Surgery was performed in 79% (8% twice), followed by conventional radiotherapy in 27%. Fifty-two per cent of the patients achieved remission. Disease control was reported in 65% of microadenomas and 41% of macroadenomas. Remission rates with surgery alone were 41%. Improvement of remission rates was achieved with subsequent treatment with somatostatin analogues (SSA) (53%), or conventional radiotherapy (63%). Nevertheless, pituitary reserve was compromised with the latter. SSA significantly improved outcomes in microadenomas, even as a monotherapy (remission in 89%), in contrast to macroadenomas (0%), although these agents were associated with impaired glucose metabolism and cholelithiasis in half of the patients. CONCLUSIONS: Acromegaly is associated with an increased morbidity. About half of the treated patients achieved remission (2/3 of microadenomas). The best outcomes were reported for the combination of surgery with radiotherapy, in spite of a higher risk of hypopituitarism. SSA led to remission in a significant percentage of microadenomas, but was associated with increased rates of cholelithiasis and impaired glucose homeostasis.