Mechanisms of action of metformin with special reference to cardiovascular protection.

Management guidelines continue to identify metformin as initial pharmacologic antidiabetic therapy of choice for people with type 2 diabetes without contraindications, despite recent randomized trials that have demonstrated significant improvements in cardiovascular outcomes with newer classes of antidiabetic therapies. The purpose of this review is to summarize the current state of knowledge of metformin's therapeutic actions on blood glucose and cardiovascular clinical evidence and to consider the mechanisms that underlie them. The effects of metformin on glycaemia occur mainly in the liver, but metformin-stimulated glucose disposal by the gut has emerged as an increasingly import site of action of metformin. Additionally, metformin induces increased secretion of GLP-1 from intestinal L-cells. Clinical cardiovascular protection with metformin is supported by three randomized outcomes trials (in newly diagnosed and late stage insulin-treated type 2 diabetes patients) and a wealth of observational data. Initial evidence suggests that cotreatment with metformin may enhance the impact of newer incretin-based therapies on cardiovascular outcomes, an important observation as metformin can be combined with any other antidiabetic agent. Multiple potential mechanisms support the concept of cardiovascular protection with metformin beyond those provided by reduced blood glucose, including weight loss, improvements in haemostatic function, reduced inflammation, and oxidative stress, and inhibition of key steps in the process of atherosclerosis. Accordingly, metformin remains well placed to support improvements in cardiovascular outcomes, from diagnosis and throughout the course of type 2 diabetes, even in this new age of improved outcomes in type 2 diabetes.

Treatment of hypovitaminosis D with pharmacologic doses of cholecalciferol, oral vs intramuscular; an open labeled RCT.

OBJECTIVE: Vitamin D deficiency is a worldwide health problem. Usual supplements are inadequate for prevention of hypovitaminosis D, and much higher doses are needed for its treatment. This study was designed to compare the efficacy and practicality of high-dose intramuscular and oral cholecalciferol in treatment of hypovitaminosis D and to evaluate durability of the effect of each remedy. DESIGN: Ninety-two patients with hypovitaminosis D [serum 25(OH) D level < 75 nmol/l] were enrolled in a randomised clinical trial. Participants were randomly assigned to receive 300 000 IU cholecalciferol, either intramuscularly as a single injection or orally in six divided doses during 3 months period. Serum 25(OH) D level was measured at baseline and at 3 and 6 months. RESULTS: Both treatment regimens significantly increased the serum 25(OH)D level. Delta change in serum 25(OH) D level from baseline (presented as mean ± SEM) at month 3 was significantly higher in oral than injection group (90 ± 11·2 and 58·8 ± 8·9 nmol/l, respectively, P = 0·03); but was similar at 6th month intervention (52·1 ± 7·6 and 62·2 ± 6·7 nmol/l, respectively, P = 0·32). There was a marginally significant trend in favour of oral group in the proportion of cases attained vitamin D adequacy at 6th month (P = 0·06); but still 15% of all patients remained at < 50 nmol/l. CONCLUSION: Both regimens were considerably effective, safe and practical in treating hypovitaminosis D. Although we revealed superiority of oral route, at least at early short time, the way of treatment may depend on the patient's choice, compliance and availability of various forms of the drug in any regions.

Role of Omega-3 fatty acids in preventing metabolic disturbances in patients on olanzapine plus either sodium valproate or lithium: a randomized double-blind placebo-controlled trial.

BACKGROUND: Metabolic and cardiovascular side effects have been noted with the use of second generation antipsychotics (SGAs) and mood stabilizers. Since Omega-3 fatty acids have been known to prevent some cardiovascular risks, this preliminary study was designed to evaluate the cardiovascular benefits of omega-3 when added to the combinations of olanzapine with mood stabilizers. METHODS: This study was a randomized, double-blind, placebo-controlled, within-subject trial in adult psychiatric patients who were receiving olanzapine combined with lithium (Li) or valproate sodium (VPA). Omega-3 as fish oil with less than 1 g/day of EPA/DHA or its placebo was added to patients' olanzapine and mood stabilizer regimens for 6 weeks. Metabolic parameters including anthropometric variables, lipid profile, metabolic syndrome indices, C-reactive protein, fibrinogen and lipoprotein (a) [(Lp) (a)] were assessed for participants. RESULTS: Forty one participants completed this study; 20 patients received omega-3 and 21 patients received placebo, added to their regimen of SGA and mood stabilizer. Omega-3 addition did not modulate anthropometric, metabolic syndrome and lipid parameter changes in 6 weeks. However, fibrinogen levels significantly decreased, Lp (a) did not increase and non-high-density lipoprotein cholesterol (non-HDL-C) did not go beyond its target level after omega-3 supplementation. Additionally, a significant inter-group effect was noted for Lp(a). CONCLUSIONS: This study suggests that use of short-term omega-3 supplementation added to a combined regimen of olanzapine and mood stabilizer may have a small modulating effect on some cardiovascular risk factors. Trials in longer periods of time and with larger number of patients are needed to further evaluate the effects of omega-3 supplements on preventing cardiovascular risk factors.This trial is registered at irct.ir and its Identifier is as following: IRCT138712231764N1.

Prediabetes management in the Middle East, Africa and Russia: Current status and call for action.

Most data on the burden of diabetes and prediabetes are from countries where local infrastructure can support reliable estimates of the burden of non-communicable diseases. Countries in the Middle East and Africa, together with Russia, have a total population of almost 2 billion, but have been relatively overlooked by authors in this field. We reviewed the prevalence and drivers of prediabetes and diabetes across this large region. A large, and variable, burden of dysglycaemia exists, especially in Middle Eastern and North African countries, associated with high levels of obesity and sedentariness, with a generally lower prevalence in most other parts of Africa. The design and size of studies are highly variable, and more research to quantify the scale of the problem is needed. Local barriers to care relating to issues concerned with gender, consanguinity, lack of understanding of diabetes, lack of understanding of obesity as a health issue, and limited resource at a national level for tracking and intervention for diabetes and other non-communicable diseases. Lifestyle interventions with proven local cost-effectiveness, enhanced access to pharmacologic intervention, and societal interventions to promote better diet and more activity will be an important element in strategies to combat these adverse trends.

Outbreak of exogenous Cushing's syndrome due to unlicensed medications.

OBJECTIVE: Despite the widespread medical use of glucocorticoids, reports of factitious administration of these hormones have been uncommon. We herein report an outbreak of Cushing's syndrome in Tehran among the addicts using Tamgesic (a brand of Buprenorphine) to help them through the narcotic withdrawal stage, without knowledge of the glucocorticoid content of the black-market drug. DESIGN AND MEASUREMENTS: Case histories of 19 patients with a final diagnosis of iatrogenic Cushing's syndrome were reviewed. Liquid chromatography/mass spectrometry (LC-Mass) method was used to evaluate glucocorticoid existence in the brand. High performance liquid chromatography was used to determine plasma dexamethasone level. RESULTS: No buprenorphine was present in the vials. Each Tamgesic vial contained 0.4 mg of Dexamethasone disodium phosphate; Heroin was also found in them. The duration of injection abuse and the total dexamethasone intake was 4.5 (1-18) months and 2.6 (0.8-8) mg/day, respectively. Median plasma dexamethasone concentration was 5.8 nmol/l, with a range of 5-8.7. Physical findings of the cases were not different from those of the classic endogenous Cushing's syndrome but their serum cortisol and urinary free cortisol were suppressed. Severe life-threatening complications were demonstrated in five cases. CONCLUSION: Surreptitious use of steroids resulting in Cushing's syndrome may be more common in opium addicts; a high degree of suspicion is needed to uncover this disorder. Whenever facing a cushingoid appearance in addicts, the possibility of using black market drugs with corticosteroid contents should be kept in mind.

Preoperative 99mTc-sestamibi scintigraphy in patients with primary hyperparathyroidism and concomitant nodular goiter: comparison of SPECT-CT, SPECT, and planar imaging.

BACKGROUND: Investigations using a hybrid single photon emission computed tomography/computed tomography (SPECT-CT) scanning technique have been carried out in limited studies and have shown mixed results. However, the assessment of this technique for the detection of parathyroid adenoma in patients with a nodular goiter was performed in only one study with a small sample size. The aim of this prospective study was to assess the role of 99mTc-sestamibi parathyroid SPECT-CT scans for localization of parathyroid adenomas with a concomitant nodular goiter using 99mTc-methoxyisobutyl isonitrile (MIBI) scintigraphy and to compare it with SPECT and planar imaging. METHODS: This study was conducted on 48 patients with primary hyperparathyroidism and nodular goiter, who were candidates for parathyroid surgery and had been referred for parathyroid scintigraphy. The patients underwent an early set of planar 99mTc-MIBI scanning procedures first, followed by SPECT and CT scannings, and finally a delayed set of planar 99mTc-MIBI scannings. Sensitivity, specificity, negative and positive predictive values, and accuracy were determined on a per-parathyroid-gland basis for each scanning method, as defined by histology and follow-up. RESULTS: The surgery was successful in 48 out of 50 patients with primary hyperparathyroidism concomitant with thyroid nodularity, and data were completed for 80 sites in 48 patients. The accuracy of SPECT-CT in correctly identifying a parathyroid adenoma was 85.00, versus 75.00% for SPECT (P=0.01, significant). The sensitivity and specificity for SPECT-CT were 77.55 and 96.77%, respectively, versus 67.34 and 87.09%, respectively, for SPECT (P=0.12 and 0.12, not significant). There were nine sites that showed better localization on SPECT-CT scans relative to SPECT images, of which five sites were located in the ectopic regions. CONCLUSION: The results of our study indicate that SPECT-CT is more accurate than sestamibi planar imaging and SPECT for the preoperative identification of parathyroid lesions in patients with primary hyperparathyroidism concomitant with thyroid nodularity. Also, we would recommend the use of SPECT-CT for a workup of all patients with ectopic glands who are scheduled for minimally invasive parathyroid surgery.