Effects of metformin on blood pressure in nondiabetic patients: a meta-analysis of randomized controlled trials

Defective natriuresis contributes to hyperkalemia in db/db mice during potassium supplementation

OBJECTIVES

Potassium supplementation reduces blood pressure and the occurrence of cardiovascular diseases, with K + -induced natriuresis playing a potential key role in this process. However, whether these beneficial effects occur in diabetes remains unknown.

METHODS

In this study, we examined the impact of high-K + intake on renal Na + /K + transport by determining the expression of major apical Na + transporters, diuretics responses (as a proxy for specific Na + transporter function), urinary Na + /K + excretion, and plasma Na + /K + concentrations in db/db mice, a model of type 2 diabetes mellitus.

RESULTS

Although db/m mice exhibited increased fractional excretion of sodium (FE Na ) and fractional excretion of potassium (FE K ) under high-K + intake, these responses were largely blunted in db/db mice, suggesting impaired K + -induced natriuresis and kaliuresis in diabetes. Consequently, high-K + intake increased plasma K + levels in db/db mice, which could be attributed to the abnormal activity of sodium-hydrogen exchanger 3 (NHE3), sodium-chloride cotransporter (NCC), and epithelial Na + channel (ENaC), as high-K + intake could not effectively decrease NHE3 and NCC and increase ENaC expression and activity in the diabetic group. Inhibition of NCC by hydrochlorothiazide could correct the hyperkalemia in db/db mice fed a high-K + diet, indicating a key role for NCC in K + -loaded diabetic mice. Treatment with metformin enhanced urinary Na + /K + excretion and normalized plasma K + levels in db/db mice with a high-K + diet, at least partially, by suppressing NCC activity.

CONCLUSION

Collectively, the impaired K + -induced natriuresis in diabetic mice under high-K + intake may be primarily attributed to impaired NCC-mediated renal K + excretion, despite the role of NHE3.

Metformin Monotherapy With and Without Lifestyle Changes Affects Anthropometric Parameters, Blood Pressure, Blood Glucose, and Lipid Profile in Indian Patients With Newly Diagnosed Type 2 Diabetes

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a consequence of insulin resistance, insulin deficiency, or both. It is usually seen in adults and is a consequence of genetic (polygenic inheritance), endogenous (obesity and or hormonal factors), and environmental factors (e.g., obesogenic environment, endocrine disrupting chemicals, stress, and medicines). The prevalence of T2DM has increased over the past few decades. South Asians, including Indians, are more prone to central adiposity and develop lifestyle diseases like T2DM at body mass index values lower than those considered normal for the Western population. Generally, the first line of treatment is metformin monotherapy with lifestyle changes in patients with T2DM. Most of the research conducted on this drug is on Western subjects. Since the Indian population has genetic differences in the site of deposition of adipose and is more prone to develop lifestyle diseases, the effect of metformin may be different in Indians.

METHODS

Seventy-one (34 female, non-pregnant, non-lactating) adults with newly diagnosed T2DM were recruited in this short-duration pilot study after obtaining written informed consent. Patients regularly taking any drug were excluded, as were patients with chronic comorbidities. Treatment was initiated with metformin 500 mg OD. Lifestyle changes were recommended according to the age and physical condition of the patients. Anthropometric parameters (age, weight, height, BMI, waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR)), blood pressure, glycemic status (fasting and 2 h PP glucose and HbA1c), and lipid profile of the subjects were recorded before initiating and six months after initiating metformin monotherapy with lifestyle changes.

RESULTS

Small but statistically significant improvements were observed in the WHR,WHtR, blood pressure, blood glucose, and glycated hemoglobin. Although improvement was also observed in weight and lipid profile, these changes were not statistically significant.

CONCLUSION

This study shows that metformin monotherapy with lifestyle changes is suitable for patients of Indian origin and results in improvement in the WHR, WHtR, blood pressure, plasma glucose, and glycated hemoglobin.

Genetically Proxied Therapeutic Effect of Metformin Use, Blood Pressure, and Hypertension's Risk: a Drug Target-Based Mendelian Randomization Study

In this work, we aim to evaluate the association of the genetically proxied effect of metformin on blood pressure (BP) and hypertension through a drug target-based Mendelian randomization (MR) analysis. Thirty-two instrumental variables for five metformin targets (i.e., AMP-activated protein kinase (AMPK), growth differentiation factor 15 (GDF15), mitochondrial glycerol 3 (MG3), mitochondrial complex I (MCI), and glucagon (GCG)) were introduced to the MR analysis on the datasets of hypertension, systolic and diastolic blood pressure (SBP and DBP). The MR analyses demonstrated that the MCI- and MG3-specific metformin's use would significantly reduce SBP, DBP, and hypertension risk. The meta-analyses showed that the genetically proxied metformin's use equivalent to a 6.75 mmol/mol reduction on HbA1c could decrease both the SBP (beta =  - 1.05, P < 0.001) and DBP (beta =  - 0.51, P = 0.096). Furthermore, metformin's use was also implied to reduce the hypertension risk. The MG3- and MCI-dependent metformin's effect may play key roles in the anti-hypertension function.

Metformin role in Parkinson's disease: a double-sword effect

Parkinson's disease (PD) is a common neurodegenerative disease developed due to the degeneration of dopaminergic neurons in the substantia nigra. There is no single effective treatment in the management of PD. Therefore, repurposing effective and approved drugs like metformin could be an effective strategy for managing PD. However, the mechanistic role of metformin in PD neuropathology was not fully elucidated. Metformin is an insulin-sensitizing agent used as a first-line therapy in the management of type 2 diabetes mellitus (T2DM) and has the ability to reduce insulin resistance (IR). Metformin may have a beneficial effect on PD neuropathology. The neuroprotective effect of metformin is mainly mediated by activating adenosine monophosphate protein kinase (AMPK), which reduces mitochondrial dysfunction, oxidative stress, and α-synuclein aggregation. As well, metformin mitigates brain IR a hallmark of PD and other neurodegenerative diseases. However, metformin may harm PD neuropathology by inducing hyperhomocysteinemia and deficiency of folate and B12. Therefore, this review aimed to find the potential role of metformin regarding its protective and detrimental effects on the pathogenesis of PD. The mechanistic role of metformin in PD neuropathology was not fully elucidated. Most studies regarding metformin and its effectiveness in PD neuropathology were observed in preclinical studies, which are not fully translated into clinical settings. In addition, metformin effect on PD neuropathology was previously clarified in T2DM, potentially linked to an increasing PD risk. These limitations hinder the conclusion concerning the therapeutic efficacy of metformin and its beneficial and detrimental role in PD. Therefore, as metformin does not cause hypoglycemia and is a safe drug, it should be evaluated in non-diabetic patients concerning PD risk.

Effects of pioglitazone and linagliptin on glycemic control, lipid profile and hs-CRP in metformin-treated patients with type 2 diabetes: a comparative study

OBJECTIVES

The purpose of this study was to compare the effects of pioglitazone and linagliptin on glycemic control, lipid profile and high-sensitivity C-reactive protein (hs-CRP) parameters in patients with type 2 diabetes treated with metformin.

METHODS

The present randomized clinical trial was conducted on 60 patients with type 2 diabetes treated with metformin in the age range of 30-60 years. The participants with informed consent were randomly assigned to receive pioglitazone or linagliptin. The first intervention group (n=30) received 30 mg of pioglitazone daily and the second intervention group (n=30) received 5 mg of linagliptin daily for 12 weeks. Fasting blood samples were taken from patients at the baseline and after 12 weeks to measure related variables. The current study was approved in Kashan University of Medical Sciences (with the code of ethics of IR.KAUMS.MEDNT.REC.1398.016), and the Iranian Registry of Clinical Trials (with the registration number of IRCT20170513033941N66).

RESULTS

The linagliptin administration significantly reduced serum levels of fasting blood sugar (p=0.03), blood sugar 2 h after a meal (p=0.02), glycosylated hemoglobin (p=0.02) and hs-CRP (p=0.005) after 12 weeks compared with pioglitazone. In contrast, the pioglitazone administration significantly decreased triglyceride levels (p=0.01) and increased HDL-cholesterol (p=0.002) compared to linagliptin. In addition, the administration of both linagliptin and pioglitazone drugs had no significant effect on LDL-cholesterol, total cholesterol, systolic and diastolic blood pressure, creatinine and blood urea.

CONCLUSIONS

The present study demonstrated the superiority of linagliptin over pioglitazone for glycemic control, although pioglitazone compared to linagliptin showed greater efficacy in reducing triglycerides and raising HDL-cholesterol.

Efficacy of metformin targets on cardiometabolic health in the general population and non-diabetic individuals: a Mendelian randomization study

BACKGROUND

Metformin shows beneficial effects on cardiometabolic health in diabetic individuals. However, the beneficial effects in the general population, especially in non-diabetic individuals are unclear. We aim to estimate the effects of perturbation of seven metformin targets on cardiometabolic health using Mendelian randomization (MR).

METHODS

Genetic variants close to metformin-targeted genes associated with expression of the corresponding genes and glycated haemoglobin (HbA1c) level were used to proxy therapeutic effects of seven metformin-related drug targets. Eight cardiometabolic phenotypes under metformin trials were selected as outcomes (average N = 466,947). MR estimates representing the weighted average effects of the seven effects of metformin targets on the eight outcomes were generated. One-sample MR was applied to estimate the averaged and target-specific effects in 338,425 non-diabetic individuals in UK Biobank.

FINDINGS

Genetically proxied averaged effects of five metformin targets, equivalent to a 0.62% reduction of HbA1c level, was associated with 37.8% lower risk of coronary artery disease (CAD) (odds ratio [OR] = 0.62, 95% confidence interval [CI] = 0.46-0.84), lower levels of body mass index (BMI) (β = -0.22, 95% CI = -0.35 to -0.09), systolic blood pressure (SBP) (β = -0.19, 95% CI = -0.28 to -0.09) and diastolic blood pressure (DBP) levels (β = -0.29, 95% CI = -0.39 to -0.19). One-sample MR suggested that the seven metformin targets showed averaged and target-specific beneficial effects on BMI, SBP and DBP in non-diabetic individuals.

INTERPRETATION

This study showed that perturbation of seven metformin targets has beneficial effects on BMI and blood pressure in non-diabetic individuals. Clinical trials are needed to investigate whether similar effects can be achieved with metformin medications.

FUNDING

Funding information is provided in the Acknowledgements.

Association of Metformin and Other Diabetes Medication Use and the Development of New-Onset Dry Age-Related Macular Degeneration: A Case-Control Study

Purpose

To investigate if metformin use is associated with decreased odds of developing new non-neovascular ("dry") age-related macular degeneration (AMD).

Methods

Case-control study examining 194,135 cases with diagnoses of new-onset AMD between 2008 and 2017 and 193,990 matched controls in the Merative MarketScan Research Databases. The diabetic subgroup included 49,988 cases and 49,460 controls. Multivariable conditional logistic regressions identified the risks of exposures on the development of dry AMD. Main outcome measures were odds ratios (ORs) of developing dry AMD with metformin use.

Results

In multivariable conditional logistic regression, any metformin use was associated with decreased odds of developing dry AMD (OR = 0.97; 95% confidence interval [CI], 0.95-0.99). This protective effect was noted for cumulative 2-year doses of metformin of 1 to 270 g (OR = 0.93; 95% CI, 0.90-0.97) and 271 to 600 g (OR = 0.92; 95% CI, 0.89-0.96). In a diabetic subgroup, metformin use below 601 g per 2 years decreased the odds of developing dry AMD (1-270 g: OR = 0.95; 95% CI, 0.91-0.99; 271-600 g: OR = 0.92; 95% CI, 0.89-0.96). Unlike in diabetic patients with diabetic retinopathy, diabetic patients without diabetic retinopathy had decreased odds of developing dry AMD with any metformin use (OR = 0.97; 95% CI, 0.94-0.998) and cumulative two-year doses of 1 to 270 g (OR 0.96; 95% CI, 0.91-0.998) and 271 to 600 g (OR = 0.92; 95% CI, 0.88-0.96).

Conclusions

Metformin use was associated with decreased odds of developing dry AMD. The protective effect was observed for cumulative 2-year doses below 601 g. In diabetics, this association persisted, specifically in those without diabetic retinopathy. Therefore, metformin may be a strategy to prevent development of dry AMD.

Metformin Suppresses Thioacetamide-Induced Chronic Kidney Disease in Association with the Upregulation of AMPK and Downregulation of Oxidative Stress and Inflammation as Well as Dyslipidemia and Hypertension

Toxic chemicals such as carbon tetrachloride and thioacetamide (TAA) are reported to induce hepato-nephrotoxicity. The potential protective outcome of the antidiabetic and pleiotropic drug metformin against TAA-induced chronic kidney disease in association with the modulation of AMP-activated protein kinase (AMPK), oxidative stress, inflammation, dyslipidemia, and systemic hypertension has not been investigated before. Therefore, 200 mg/kg TAA was injected (via the intraperitoneal route) in a model group of rats twice a week starting at week 3 for 8 weeks. The control rats were injected with the vehicle for the same period. The metformin-treated group received 200 mg/kg metformin daily for 10 weeks, beginning week 1, and received TAA injections with dosage and timing similar to those of the model group. All rats were culled at week 10. It was observed that TAA induced substantial renal injury, as demonstrated by significant kidney tissue damage and fibrosis, as well as augmented blood and kidney tissue levels of urea, creatinine, inflammation, oxidative stress, dyslipidemia, tissue inhibitor of metalloproteinases-1 (TIMP-1), and hypertension. TAA nephrotoxicity substantially inhibited the renal expression of phosphorylated AMPK. All these markers were significantly protected by metformin administration. In addition, a link between kidney fibrosis and these parameters was observed. Thus, metformin provides profound protection against TAA-induced kidney damage and fibrosis associated with the augmentation of the tissue protective enzyme AMPK and inhibition of oxidative stress, inflammation, the profibrogenic gene TIMP-1, dyslipidemia, and hypertension for a period of 10 weeks in rats.

[Obstructive sleep apnea syndrome and cardiovascular risk factors in the antihypertensive therapy "escape" phenomenon]

AIM

To assess the role of obstructive sleep apnea and other cardiovascular (CV) risk factors in the development of the antihypertensive therapy (AHT) efficacy "escape" phenomenon in patients with arterial hypertension (AH).

MATERIALS AND METHODS

The data of 75 patients with AH stage I-II, grades 1-3 were proceeded. All patients included in the study underwent night respiratory monitoring. After AHT prescription, blood pressure (BP) was monitored by three measurement methods (office, daily monitoring and self-control of blood pressure) - initially, in 1, 3 and 6 months after the inclusion - in order to confirm the initial therapy efficacy and to identify or exclude the "escape" phenomenon.

RESULTS

In 36.0% of patients, the "escape" phenomenon was diagnosed in 1 or 3 months of observation. When comparing the group with the "escape" phenomenon, an initially higher level of systolic BP was revealed according to office measurements, 24-hour monitoring and self-control BP monitoring (134.0±4.7 mmHg vs 126.0±8.5 mmHg; 129.0±2.3 mmHg vs 121.0±7.7 mmHg; 131.0±8.2 mmHg vs 121.5±6.2 mmHg resp.; р<0,05). There were no differences in sleep apnea and CV risk factors between the groups. However in patients with a minimal SpO₂≤85% during sleep, there were a higher levels of office systolic BP both before the AHT prescription, and during its use (157.6±10.4 mmHg vs 152.4±8.1 mmHg resp., р<0,05; 132.0±6.8 vs 127.1±8.9 mmHg resp.; р<0,05), and mean 24-hour systolic BP (125.7±5.9 vs 121.6±8.2 mmHg resp.; р<0,05) - compared with patients with a minimum SpO₂>85%.

CONCLUSION

The higher BP level in patients with lover nocturnal hypoxemia does not allow us to exclude the delayed negative impact of obstructive sleep apnea, especially severe, on the BP profile in case of initially successful AH control.

Pharmacotherapy of type 2 diabetes: An update and future directions

Type 2 diabetes (T2D) is a widely prevalent disease with substantial economic and social impact for which multiple conventional and novel pharmacotherapies are currently available; however, the landscape of T2D treatment is constantly changing as new therapies emerge and the understanding of currently available agents deepens. This review aims to provide an updated summary of the pharmacotherapeutic approach to T2D. Each class of agents is presented by mechanism of action, details of administration, side effect profile, cost, and use in certain populations including heart failure, non-alcoholic fatty liver disease, obesity, chronic kidney disease, and older individuals. We also review targets of novel therapeutic T2D agent development. Finally, we outline an up-to-date treatment approach that starts with identification of an individualized goal for glycemic control then selection, initiation, and further intensification of a personalized therapeutic plan for T2D.

Effect of metformin on left ventricular mass and functional parameters in non-diabetic patients: a meta-analysis of randomized clinical trials

BACKGROUND

Left ventricular hypertrophy is a common finding in patients with ischemic heart disease and is associated with mortality in patients with cardiovascular disease (CVD). Metformin, an antidiabetic drug, has been shown to reduce oxidative stress and left ventricular mass index (LVMI) in animal hypertrophy models. We summarized evidence regarding the effect of metformin on LVMI and LVEF.

METHODS

Electronic databases were searched for randomized clinical trials (RCTs) that used metformin in non-diabetic patients with or without pre-existing CVD. The standardized mean change using change score standardization (SMCC) was calculated for each study. The random-effects model was used to pool the SMCC across studies. Meta-regression analysis was used to assess the association of heart failure (HF), metformin dose, and duration with the SMCC.

RESULTS

Data synthesis from nine RCTs (754 patients) showed that metformin use resulted in higher reduction in LVMI after 12 months (SMCC = -0.63, 95% CI - 1.23; - 0.04, p = 0.04) and an overall higher reduction in LVMI (SMCC = -0.5, 95% CI - 0.84; - 0.16, p < 0.01). These values equate to absolute values of 11.3 (95% CI 22.1-0.72) and 8.97 (95% CI 15.06-2.87) g/m2, respectively. The overall improvement in LVEF was also higher in metformin users after excluding one outlier (SMCC = 0.26, 95% CI 0.03-0.49, P = 0.03) which translates to a higher absolute improvement of 2.99% (95% CI 0.34; 5.63). Subgroup analysis revealed a favorable effect for metformin on LVEF in patients who received > 1000 mg/day (SMCC = 0.28, 95% CI 0.04; 0.52, P = 0.04), and patients with HF (SMCC = 0.23; 95% CI 0.1; 0.36; P = 0.004). These values translate to a higher increase of 2.64% and 3.21%, respectively.

CONCLUSION

Results suggest a favorable effect for metformin on LVMI and LVEF in patients with or without pre-existing CVD. Additional trials are needed to address the long-term effect of metformin. Registration The study was registered on the PROSPERO database with the registration number CRD42021239368 ( https://www.crd.york.ac.uk/prospero ).

Cardiovascular Effects of Metformin

Type 2 diabetes mellitus is one of the most important independent risk factors for the development, progression and mortality from cardiovascular diseases (CVD). The world communities are faced with the question of developing the optimal management tactics for such comorbidity patients. Thus, the prescribed drug should not only have an adequate hypoglycemic effect, but also have a number of cardioprotective properties, be safe in patients with CVD, and possibly even improve the prognosis and reduce mortality rates. This review is devoted to a representative of the biguanide class - metformin, which is one of the earliest and most effective antihyperglycemic drugs, both as monotherapy and in combination with other antihyperglycemic drugs and insulin; while the evidence base for its cardiovascular profile is only gaining momentum. Thus, the purpose of this review is to highlight the cardiovascular effects of metformin in the context of recent research.

Effects of Metformin in Heart Failure: From Pathophysiological Rationale to Clinical Evidence

Type 2 diabetes mellitus (T2DM) is a worldwide major health burden and heart failure (HF) is the most common cardiovascular (CV) complication in affected patients. Therefore, identifying the best pharmacological approach for glycemic control, which is also useful to prevent and ameliorate the prognosis of HF, represents a crucial issue. Currently, the choice is between the new drugs sodium/glucose co-transporter 2 inhibitors that have consistently shown in large CV outcome trials (CVOTs) to reduce the risk of HF-related outcomes in T2DM, and metformin, an old medicament that might end up relegated to the background while exerting interesting protective effects on multiple organs among which include heart failure. When compared with other antihyperglycemic medications, metformin has been demonstrated to be safe and to lower morbidity and mortality for HF, even if these results are difficult to interpret as they emerged mainly from observational studies. Meta-analyses of randomized controlled clinical trials have not produced positive results on the risk or clinical course of HF and sadly, large CV outcome trials are lacking. The point of force of metformin with respect to new diabetic drugs is the amount of data from experimental investigations that, for more than twenty years, still continues to provide mechanistic explanations of the several favorable actions in heart failure such as, the improvement of the myocardial energy metabolic status by modulation of glucose and lipid metabolism, the attenuation of oxidative stress and inflammation, and the inhibition of myocardial cell apoptosis, leading to reduced cardiac remodeling and preserved left ventricular function. In the hope that specific large-scale trials will be carried out to definitively establish the metformin benefit in terms of HF failure outcomes, we reviewed the literature in this field, summarizing the available evidence from experimental and clinical studies reporting on effects in heart metabolism, function, and structure, and the prominent pathophysiological mechanisms involved.

Real-World Clinical Experience on the Usage of High-Dose Metformin (1500-2500 mg/day) in Type 2 Diabetes Management

Background:

To evaluate the clinical characteristics, treatment patterns, and clinical effectiveness and safety of high doses of metformin (1500-2500 mg/day) in Indian adults with type 2 diabetes mellitus (T2DM).

Materials and methods:

A retrospective, multicentric (n = 241), real-world study included patients with T2DM (aged >18 years) receiving high doses of metformin. Details were retrieved from patient’s medical records.

Results:

Out of 5695 patients, 62.7% were men with median age was 50.0 years. Hypertension (67.5%) and dyslipidemia (48.7%) were the prevalent comorbidities. Doses of 2000 mg (57.4%) and 1500 mg (29.1%) were the most commonly used doses of metformin and median duration of high-dose metformin therapy was 24.0 months. Metformin twice daily was the most frequently used dosage pattern (94.2%). Up-titration of doses was done in 96.8% of patients. The mean HbA1c levels were significantly decreased post-treatment (mean change: 1.08%; P < .001). The target glycemic control was achieved in 91.2% patients. A total of 83.0% had decreased weight. Adverse events were reported in 156 patients. Physician global evaluation of efficacy and tolerability showed majority of patients on a good to excellent scale (98.2% and 97.7%).

Conclusion:

Clinical effectiveness and safety of a high-dose metformin was demonstrated through significant improvement in HbA1c levels and weight reduction.

Cardiovascular Safety and Benefits of Noninsulin Antihyperglycemic Drugs for the Treatment of Type 2 Diabetes Mellitus-Part 1

Cardiovascular disease (CVD) is a major contributor to the morbidity and mortality associated with type 2 diabetes mellitus (T2DM). With T2DM growing in pandemic proportions, there will be profound healthcare implications of CVD in person with diabetes. The ideal drugs to improve outcomes in T2DM are those having antiglycemic efficacy in addition to cardiovascular (CV) safety, which has to be determined in appropriately designed CV outcome trials as mandated by regulatory agencies. Available evidence is largely supportive of metformin's CV safety and potential CVD risk reduction effects, whereas sulfonylureas are either CV risk neutral or are associated with variable CVD risk. Pioglitazone was also associated with improved CVD risk in patients with diabetes. The more recent antihyperglycemic medications have shown promise with regards to CVD risk reduction in T2DM patients at a high CV risk. Glucagon-like peptide-1 receptor agonists, a type of incretin-based therapy, were associated with better CV outcomes and mortality in T2DM patients, leading to the Food and Drug Administration approval of liraglutide to reduce CVD risk in high-risk T2DM patients. Ongoing and planned randomized controlled trials of the newer drugs should clarify the possibility of class effects, and of CVD risk reduction benefits in low-moderate CV risk patients. While metformin remains the first-line antiglycemic therapy in T2DM, glucagon-like peptide-1 receptor agonists should be appropriately prescribed in T2DM patients with baseline CVD or in those at a high CVD risk to improve CV outcomes. Dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter-2 inhibitors are discussed in the second part of this review.

A Comparison Between the Therapeutic Effect of Metformin Alone versus a Combination Therapy with Insulin in Uncontrolled, Non-Adherence Patients with Type 2 Diabetes: Six Months Follow-Up

PURPOSE

The study aimed to compare the metabolic effects of an intensive dose of metformin alone among non-adherence patients with type 2 diabetes versus in combination with insulin among adherence patients.

METHODS

The prospective cohort study was carried out on a sample of 140 patients above 18 years old, divided into two groups. The first group (n=70) was recommended metformin monotherapy in an intensive dose of 2-3 g/day, whereas the second group (n=70) was prescribed metformin (1-2g/day) in combination with insulin. FPG, HbA1c, BMI, blood pressure, TC, TG, HDL-C, LDL-C, creatinine, and eGFR were measured for each patient at baseline and after a follow-up of 6 months of active treatment.

RESULTS

After six months of active treatment using monotherapy with an intensive dose of metformin, only 11.43% of patients achieved the target levels of HBA1c below 7%. In the group of patients treated using a combination of metformin with insulin, after six months of active treatment, 45.72% achieved HBA1c levels below 7% (p<0.0001). Compared with an intensive dose of metformin alone, the combination of insulin and metformin was associated with improved glycemic control (change of fasting blood glucose: 2.49 mmol/l vs 1.30 mmol/l, p=0.0016). Metformin use alone, as compared with insulin, was associated with a significant increase in HDL-C (+0.03 mmol/l vs -0.14 mmol/l, p=0.0485). Increased baseline obesity and increased baseline glycemia were the factors related to the likelihood of failing to achieve the target levels for HbA1c.

CONCLUSION

Metformin proved to be more effective in controlling hyperglycemia when combined with insulin therapy. Our study shows how many health benefits loss patients who, despite systematic diabetes education, do not agree to change their treatment in the form of adding a second drug, including insulin.

The impact of glycated hemoglobin on risk of hypertension: a Mendelian randomization study using UK Biobank

BACKGROUND

Observational studies suggest higher glycated hemoglobin (HbA1c) associated with higher hypertension risk although these associations could be confounded. We examined the relation using a Mendelian randomization design in a large Biobank, the UK Biobank.

METHODS

We identified 38 single nucleotide polymorphisms (SNPs) strongly and independently related to HbA1c from a large genome wide association study (n = 123 665) and applied them to the UK Biobank (n = 376 644). We used inverse variance weighting (IVW) to assess the relation of HbA1c with risk of hypertension (defined using the American College of Cardiology/American Heart Association 2017 guidelines), and SBP and DBP. Sensitivity analyses included Mendelian randomization-Egger, weighted median, Mendelian randomization pleiotropy residual sum and outlier and exclusion of pleiotropic SNPs.

RESULTS

HbA1c was not clearly associated with hypertension risk using IVW (odds ratio 1.11, 95% confidence interval 0.76-1.62) in the main analysis. However, Mendelian randomization pleiotropy residual sum and outlier suggested potential horizontal pleiotropy. After excluding potentially invalid SNPs, HbA1c was associated with hypertension risk (IVW odds ratio 1.22 per %, 95% confidence interval 1.01-1.46), with consistent estimates from sensitivity analyses. HbA1c was positively associated with SBP in some, but not all analyses, albeit with directionally consistent estimates. The relation with DBP was unclear.

CONCLUSION

Our study suggests HbA1c may increase hypertension risk and could be one underlying mechanistic pathway between HbA1c and coronary artery disease risk.

A randomized controlled trial of metformin on left ventricular hypertrophy in patients with coronary artery disease without diabetes: the MET-REMODEL trial

Aim

We tested the hypothesis that metformin may regress left ventricular hypertrophy (LVH) in patients who have coronary artery disease (CAD), with insulin resistance (IR) and/or pre-diabetes.

Methods and results

We randomly assigned 68 patients (mean age 65 ± 8 years) without diabetes who have CAD with IR and/or pre-diabetes to receive either metformin XL (2000 mg daily dose) or placebo for 12 months. Primary endpoint was change in left ventricular mass indexed to height^1.7 (LVMI), assessed by magnetic resonance imaging. In the modified intention-to-treat analysis (n = 63), metformin treatment significantly reduced LVMI compared with placebo group (absolute mean difference −1.37 (95% confidence interval: −2.63 to −0.12, P = 0.033). Metformin also significantly reduced other secondary study endpoints such as: LVM (P = 0.032), body weight (P = 0.001), subcutaneous adipose tissue (P = 0.024), office systolic blood pressure (BP, P = 0.022) and concentration of thiobarbituric acid reactive substances, a biomarker for oxidative stress (P = 0.04). The glycated haemoglobin A1C concentration and fasting IR index did not differ between study groups at the end of the study.

Conclusion

Metformin treatment significantly reduced LVMI, LVM, office systolic BP, body weight, and oxidative stress. Although LVH is a good surrogate marker of cardiovascular (CV) outcome, conclusive evidence for the cardio-protective role of metformin is required from large CV outcomes trials.

Role of metformin in various pathologies: state-of-the-art microcapsules for improving its pharmacokinetics

Metformin was originally derived from a botanical ancestry and became the most prescribed, first-line therapy for Type 2 diabetes in most countries. In the last century, metformin was discovered twice for its antiglycemic properties in addition to its antimalarial and anti-influenza effects. Metformin exhibits flip-flop pharmacokinetics with limited oral bioavailability. This review outlines metformin pharmacokinetics, pharmacodynamics and recent advances in polymeric particulate delivery systems as a potential tool to target metformin delivery to specific tissues/organs. This interesting biguanide is being rediscovered this century for multiple clinical indications as anticancer, anti-aging, anti-inflammatory, anti-Alzheimer's and much more. Microparticulate delivery systems of metformin may improve its oral bioavailability and optimize the therapeutic goals expected.

Impact of thioctic acid on glycemic indices and associated inflammatory-induced endothelial dysfunction in patients with type 2 diabetes mellitus: A case control study

Objective

To evaluate the effects of thioctic acid (TA) add-on metformin therapy on glycemic indices and associated inflammatory reactions induced-endothelial dysfunction (ED) in patients with type 2 diabetes mellitus (T2DM).

Methods

In this case-control clinical study, a total number of 70 patients with T2DM compared with 30 healthy controls were divided into three groups: Group A (n = 30), healthy controls; Group B (n = 36), T2DM patients on metformin and Group C (n = 34), T2DM patients on metformin plus TA 600 mg/day. Anthropometric measurements, lipid profile, and routine biochemical variables were estimated. Serum human vascular cell adhesion molecule-1 (VCAM-1) and E-selectin were measured before and after 10 consecutive week's therapy with metformin and/or TA.

Results

Metformin therapy led to significant reduction of fasting insulin and insulin resistance (IR) with an increment in the insulin sensitivity (P < 0.01). Metformin therapy improved lipid profile compared to the baseline (P < 0.01) with significant reduction of atherogenic index. Metformin plus TA therapy reduced fasting blood glucose, glycated hemoglobin, and IR and showed increment in the insulin sensitivity (P < 0.01) with insignificant effect on fasting insulin (P = 0.09) compared with metformin monotherapy. sVCAM-1 level was high in patients with T2DM (3.74 ± 1.34 ng/ml) at baseline, which decreased by metformin monotherapy to 2.32 ± 0.67 ng/ml or metformin plus TA to 1.98 ± 0.31 ng/ml (P < 0.01), but metformin plus TA illustrated insignificant difference compared to metformin alone (P = 0.29).

Conclusion

TA add on metformin therapy improves glycemic indices and associated inflammatory mediators in patients with T2DM through modulation of IR , IS , and direct direct anti-inflammatory effect.

Antidiabetic drugs and blood pressure changes

New era antidiabetic drugs are characterized by cardiovascular safety, including specific outcome benefits observed in randomized clinical trials (RCTs). It has been postulated that the favorable effects of new antidiabetic agents are related both to better control of blood pressure (BP) levels and to activation of multiple anti-atherosclerotic properties. In this review, we aimed to assess whether antidiabetic drugs have a pressor effect in glucose control and outcome-oriented RCTs, and to summarize the activated pathophysiological mechanisms relevant to BP control following the use of different antidiabetic drug classes. We also tried to determine which, if any, are the BP-lowering effects of more intense vs less intense glucose-lowering strategy irrespectively of trial antidiabetic regimen. To provide more robust results and evidence-based argumentation, a meta-analysis of placebo-controlled antidiabetic drug RCTs was undertaken to estimate the ongoing BP reduction for all considered and each separate drug class alone. This quantitative synthesis might be helpful for the clinician 1) to select or avoid the use of some classes of antidiabetic agents with a potential favorable or adverse pressor effect, respectively 2) to organize the overall drug regimen in patients with diabetes mellitus and minimize side effects because of concomitant use of drugs with established pressor effect (i.e. antihypertensive agents). This review was also organized to indicate whether BP change associated with different antidiabetic treatments may explain the specific macrovascular outcome benefits. Between all antidiabetic drugs including exogenous insulin, only sodium-glucose cotransporter 2 inhibitors produce a clinically important BP-lowering effect, but this BP reduction alone cannot explain the observed cardiovascular benefit.

The Effect of Metformin on Thyroid-Associated Serum Hormone Levels and Physiological Indexes: A Meta-Analysis

BACKGROUND

Many diseases can be treated with metformin. People with serum thyrotropin (TSH) levels higher than 10 mIU/L are at a risk of cardiovascular events. Some studies have suggested that metformin can lower serum TSH levels to a subnormal level in patients with hyperthyrotropinaemia or hypothyroidism.

OBJECTIVE

The objective of this analysis is to evaluate the effect of metformin treatment on serum TSH, free triiodothyronine (FT3), and free thyroxine (FT4) levels and other associated physiological indices.

METHODS

A comprehensive search using the PubMed, EMBASE, Web of Science and Cochrane Central databases was undertaken for controlled trials on the effect of metformin on serum TSH, FT3, and FT4 levels and associated physiological indices. The primary outcome measures were serum TSH, FT3 and FT4 levels, thyroid size, thyroid nodule size, blood pressure, heart rate, body weight, and body mass index (BMI). The final search was conducted in April 2019.

RESULTS

Six RCTs were included. A total of 494 patients met the inclusion criteria. Metformin treatment did not significantly lower the serum TSH levels at 3 or 6 months but did at 12 months. Moreover, forest plots also suggested that metformin can significantly lower the serum TSH levels in patients with normal thyroid function but cannot statistically change the serum TSH levels in patients with abnormal thyroid function. In addition, metformin treatment clearly lowered the serum FT3 levels and had no significant effect on serum FT4 levels. Lastly, metformin cannot significantly change the systolic blood pressure (SBP) or BMI but can clearly increase the diastolic blood pressure (DBP).

CONCLUSION

Metformin treatment can significantly lower the serum TSH levels, and this effect was much clearer after a 12-month treatment duration and in people with normal thyroid function. However, metformin cannot significantly change the serum FT4 levels or lower serum FT3 levels in people with non-thyroid cancer diseases. In addition, metformin can significantly increase DBP, but it has no clear effect on SBP or BMI.

The Use of Metformin to Increase the Human Healthspan

Metformin is a safe, effective and useful drug for glucose management in patients with diabetes. However in recent years, more attention has been paid to the possibility of using metformin as an anti-aging drug. It was shown to significantly increase the lifespan in some model organisms and delay the onset of age-associated declines. The current review summarizes advances in clinical research on the potential role of metformin in the field of lifespan and healthspan extension. Growing amounts of evidence from clinical trials suggest that metformin can effectively reduce the risk of many age-related diseases and conditions, including cardiometabolic disorders, neurodegeneration, chronic inflammation and frailty. Metformin also holds promise as a drug that could be repurposed for chemoprevention or adjuvant therapy for certain types of cancer. Moreover, metformin induces autophagy by activation of AMPK and can thus be potentially used to promote heathspan by hormesis-like mechanisms. Although long-term intake of metformin is associated with low risk of adverse events, well-designed clinical trials are still required to uncover the potential use of this drug as a geroprotector.

Chronic metformin reduces systemic and local inflammatory proteins and improves hypertension-related cardiac autonomic dysfunction

BACKGROUND AND AIMS

Metformin has been known to promote cardiovascular benefits in humans and animal models, even in non-diabetic subjects. However, its chronic effects on hypertension-related autonomic dysfunction remain poorly understood. Therefore, we evaluate the cardiac autonomic effects of chronic metformin in hypertensive rats.

METHODS AND RESULTS

Twelve-week-old male SHR and Wistar rats were separated into 3 groups: WN (Wistar normotensive); SC (SHR hypertensive control); and SM (SHR: Metformin 300 mg/kg/day for 30 days). Spontaneous and induced (by phenylephrine and sodium nitroprusside) baroreflexes were analysed in catheterised rats. Next, cardiac autonomic tone was evaluated through heart rate shift by atropine (parasympathetic) or atenolol (sympathetic). Plasma TNFα was assessed by ELISA. Western blot analyses of inflammatory, oxidant and antioxidant proteins were performed. Cardiac parasympathetic tone and baroreflex function were lower in SC than in WN, whereas cardiac sympathetic tone was higher. Metformin treatment in non-diabetic hypertensive rats reduced the resting heart rate, attenuated the cardiac sympathetic tone and improved baroreflex (especially in the offsetting of rising BP), while blood pressure and glycaemia remained unchanged. Cardiac sympathetic tone correlated negatively with spontaneous baroreflex. Metformin reduced plasma TNFα levels and decreased tissue expression of COX2 and NOX2 (which were positively correlated), without affecting SOD1 and SOD2.

CONCLUSION

Chronic metformin presented anti-inflammatory and antioxidant effects and, independently of alterations in glycaemia, it improved cardiac autonomic parameters that are impaired in hypertension, being related to end-organ damage and mortality. These findings open up perspectives for future innovative uses of metformin in cardiovascular diseases, especially in hypertension.

Effects of metformin on blood lipid profiles in nondiabetic adults: a meta-analysis of randomized controlled trials

PURPOSE

To evaluate the effects of metformin on serum lipid profiles in nondiabetic adults through a comprehensive meta-analysis.

METHODS

In the present meta-analysis, randomized and controlled trials were collected by searching PubMed, Embase, and Cochrane Libraries from inception to April 2019. Compared with placebos, the effects of metformin treatment on lipid profiles in nondiabetic adults were evaluated.

RESULTS

Forty-seven studies from 45 articles including 5731 participants were enrolled. Pooled results showed that metformin had significant effects on total cholesterol (mean change -6.57 mg/dl; 95% CI -9.66, -3.47; P = 0.000) and LDL-c (mean change -4.69 mg/dl; 95% CI -7.38, -2.00; P = 0.001), but insignificant effects on HDL-c (mean change -4.33 mg/dl; 95% CI -9.62, 0.96; P = 0.109) and triglyceride (mean change -0.85 mg/dl; 95% CI -0.36, 2.06; P = 0.169). Significant heterogeneities were found for all lipid profiles (HDL-c = 85.5%; LDL-c = 59.9%; total cholesterol = 75.3% and triglyceride = 67.1%). Different from the pooled data, in a subgroup analysis, the effect of metformin on triglyceride in patients with polycystic ovarian syndrome (PCOS) was significant with a mean reduction of 8.15 mg/dl. In addition, sensitivity analysis showed that the pooled effects of metformin on serum lipid profiles were stable. Publication bias derived from funnel plots or Begg's tests (P = 0.933, 0.860, 0.904, and 0.567 for HDL-c, LDL-c, total cholesterol, and triglyceride, respectively) was not significant.

CONCLUSION

This meta-analysis revealed that metformin could reduce total cholesterol and LDL-c in nondiabetic adults. In addition, metformin might exert a triglyceride-lowering effect in nondiabetics with PCOS status.

Metformin: An old drug against old age and associated morbidities

Metformin represents a striking example of a "historical nemesis" of a drug. About 40 years after its marketing in Europe, once demonstrated its efficacy and safety, metformin was registered also in the U.S. A few years later, it has become a mainstay in T2DM treatment, according to all international Scientific Societies guidelines. Today, despite the advent of new innovative drugs, metformin still persists as a first-choice drug in T2DM. This success is largely justified. In fact, over the years, also positive effects on health increased. In particular, evidence has been accumulated on a beneficial impact against many other aging-related morbidities (obesity, metabolic syndrome, cardiovascular disease, cancer, cognitive decline and mortality). This literature review describes preclinical and clinical evidence favoring the "anti-aging" therapeutic potential of metformin outside of T2DM. The rationale to the use of metformin as part of a combined therapy in a variety of clinical settings, allowing for a reduction of the chemotherapy dose in cancer patients, has also been discussed. In particular, the focus was on metformin action on RAS/RAF/MAPK pathway. In the end, the real challenge for metformin could be to fully demonstrate beneficial effects on health even in non-diabetic subjects.

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.

Correlation between glycosylated hemoglobin level of patients with diabetes and cardiovascular disease

OBJECTIVE

To explore the clinical influence of the changes of glycosylated hemoglobin level of patients with diabetes on hypertension and coronary heart disease.

METHODS

One hundred and ninety-six patients between February 2015 and December 2016 were divided into a control group (96 non-diabetic patients) and an observation group (100 patients with diabetes) with or without diabetes. The biochemical indexes of patients in the two groups were compared. Moreover patients in the observation groups were divided into subgroups according to the presence of hypertension and coronary heart disease, and the level of HbA1c was compared between different subgroups.

RESULTS

The levels of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) of patients in the two groups had no significant differences (P>0.05). However, the level of high-density lipoprotein cholesterol (HDL-C) of patients in the observation group was significantly lower than that of the control group (P<0.05). The Systolic Blood Pressure (SBP) and diastolic blood pressure (DBP), fasting plasma glucose (FPG), fasting insulin (FINS) and levels of high-sensitivity C-reactive protein (hs-CRP) and HbA1c of patients in the observation group were apparently higher than those of the control group (P<0.05). The level of HbA1c of patients with hypertension was significantly higher than that without hypertension (P<0.05). The level of HbA1c of patients with coronary heart disease was apparently higher than that without coronary heart disease (P<0.05). The Pearson correlation analysis results demonstrated that the level of HbA1c of patients in the diabetes group was in a positive correlation with SBP, DBP and level of hs-CRP (P<0.05).

CONCLUSION

The level of HbA1c of patients with diabetes was in a positive correlation with blood pressure and level of hs-CRP. The level of HbA1c can effectively predict the occurrence of hypertension and coronary heart disease. Detecting level of glycosylated hemoglobin is of important significance in screening patients with hypertension and coronary heart disease.

Effect of metformin on blood pressure in patients with hypertension: a randomized clinical trial

OBJECTIVE

Part of the beneficial effects of metformin on the prevention of cardiovascular events in diabetes can be attributed to pleiotropic effects, including a blood pressure (BP)-lowering effect. In a double-blind parallel clinical trial (NCT02072382), the effect of metformin on BP evaluated by ambulatory blood pressure monitoring (ABPM) was measured.

METHODS

Ninety-seven patients with hypertension, but without diabetes mellitus, were randomized to receive 850-1700 mg of metformin (n = 48) or placebo (n = 49). Clinical, laboratory, and ABPM data were collected at the baseline and after 8 weeks of follow-up.

RESULTS

The sample consisted mainly of White overweight women. There was no difference in BP reduction measured by ABPM between both groups. There was no effect in BP measured in the different periods of ABP monitoring and office BP. Additionally, fasting plasma glucose, lipids, and C-reactive protein remained unchanged during the trial. There was a significant reduction in waist circumference with metformin (95.1 ± 10.4 to 89.3 ± 27.4 cm; p = 0.02).

CONCLUSION

In the present trial, metformin did not reduce BP, measured by ABP monitoring, in hypertensive patients without diabetes.

Metformin prevents vascular damage in hypertension through the AMPK/ER stress pathway

Metformin is an antidiabetic drug. However, the pleiotropic beneficial effects of metformin in nondiabetic models still need to be defined. The objective of this study is to investigate the effect of metformin on angiotensin II (Ang II)-induced hypertension and cardiovascular diseases. Mice were infused with Ang II (400 ng/kg per min) with or without metformin for 2 weeks. Mice infused with angiotensin II displayed an increase in blood pressure associated with enhanced vascular endoplasmic reticulum (ER) stress markers, which were blunted after metformin treatment. Moreover, hypertension-induced reduction in phosphorylated AMPK, endothelial nitric oxide synthase (eNOs) phosphorylation, and endothelium-dependent relaxation (EDR) in mesenteric resistance arteries (MRA) were rescued after metformin treatment. Infusion of ER stress inducer (tunicamycin, Tun) in control mice induced ER stress in MRA and reduced phosphorylation of AMPK, eNOS synthase phosphorylation, and EDR in MRA without affecting systolic blood pressure (SBP). All these factors were reversed subsequently with metformin treatment. ER stress inhibition by metformin improves vascular function in hypertension. Therefore, metformin could be a potential therapy for cardiovascular diseases in hypertension independent of its effects on diabetes.

Metformin as a geroprotector: experimental and clinical evidence

Apart from being a safe, effective and globally affordable glucose-lowering agent for the treatment of diabetes, metformin has earned much credit in recent years as a potential anti-aging formula. It has been shown to significantly increase lifespan and delay the onset of age-associated decline in several experimental models. The current review summarizes advances in clinical research on the potential role of metformin in the field of geroprotection, highlighting findings from pre-clinical studies on known and putative mechanisms behind its beneficial properties. A growing body of evidence from clinical trials demonstrates that metformin can effectively reduce the risk of many age-related diseases and conditions, including cardiometabolic disorders, neurodegeneration, cancer, chronic inflammation, and frailty. Metformin also holds promise as a drug that could be repurposed for chemoprevention or adjuvant therapy for certain cancer types. Moreover, due to the ability of metformin to induce autophagy by activation of AMPK, it is regarded as a potential hormesis-inducing agent with healthspan-promoting and pro-longevity properties. Long-term intake of metformin is associated with low risk of adverse events; however, well-designed clinical trials are still warranted to enable potential use of this therapeutic agent as a geroprotector.

Metformin increases urinary sodium excretion by reducing phosphorylation of the sodium-chloride cotransporter

OBJECTIVE

Metformin is an antidiabetic drug that is widely used to treat patients with diabetes mellitus. Recent studies have reported that treatment with metformin not only improved blood glucose levels but also reduced blood pressure. However, it remains unclear how metformin reduces blood pressure. We hypothesized that metformin affects sodium reabsorption in the kidneys.

METHODS

Urinary sodium excretion and expression of renal sodium transporters were examined in 8-week-old male C57BL/6 mice with acute and chronic treatment of metformin. In addition, we examined metformin effects using ex vivo preparations of mice kidney slices.

RESULTS

In this study, we demonstrated that metformin increased urinary sodium excretion by reducing phosphorylation of the thiazide-sensitive Na-Cl cotransporter (NCC) in acute and chronic metformin administration. We also confirmed reduction of phosphorylated NCC in an ex vivo study. The activity of other renal sodium transporters, such as NKCC2, ENaC, and NHE3 did not show significant changes. WNK-OSR1/SPAK kinase signals were not involved in this inactivation effect of metformin on NCC.

CONCLUSION

Metformin increased urinary sodium excretion by reducing phosphorylation of NCC, suggesting its role in improving hypertension.

Effects of Different Dietary and Lifestyle Modification Therapies on Metabolic Syndrome in Prediabetic Arab Patients: A 12-Month Longitudinal Study

This three-arm, randomized, controlled study aimed to determine the differences in the effects of general advice (GA) on lifestyle change, intensive lifestyle modification programme (ILMP) and GA + metformin (GA + Met) in reducing the prevalence of full metabolic syndrome (MetS) in subjects with prediabetes; 294 Saudis with prediabetes (fasting glucose 5.6–6.9 mmol/L) were initially randomized, 263 completed 6 months and 237 completed 12 months. They were allocated into three groups: GA group which received a standard lifestyle change education; ILMP which followed a rigorous lifestyle modification support on diet and physical activity; and a GA + Met group. Anthropometric and biochemical estimations were measured. Full MetS (primary endpoint) and its components (secondary endpoint) were screened at baseline, 6 and 12 months. Full MetS in the ILMP group decreased by 26% (p < 0.001); in GA + Met group by 22.4% (p = 0.01) and in GA group by 8.2% (p = 0.28). The number of MetS components decreased significantly in the ILMP and GA + Met groups (mean change 0.81, p < 0.001 and 0.35, p = 0.05, respectively). Between-group comparison revealed a clinically significant decrease in MetS components in favor of the ILMP group (−0.58 (−0.88–0.28), p < 0.001). This study highlights the clinical potency of ILMP versus other diabetes prevention options in reducing MetS in Saudi adults with elevated fasting glucose.

Pulse pressure and diabetes treatments: Blood pressure and pulse pressure difference among glucose lowering modality groups in type 2 diabetes

Type 2 diabetes is associated with higher pulse pressure. In this study, we assessed and compared effects of classic diabetes treatments on pulse pressure (PP), systolic blood pressure (SBP), and diastolic blood pressure (DBP) in patients with type 2 diabetes.In a retrospective cohort study, 718 non-hypertensive patients with type 2 diabetes were selected and divided into 4 groups including metformin, insulin, glibenclamide+metformin, and metformin+insulin. They were followed for 4 consecutive visits lasting about 45.5 months. Effects of drug regimens on pulse and blood pressure over time were assessed separately and compared in regression models with generalized estimating equation method and were adjusted for age, duration of diabetes, sex, smoking, and body mass index (BMI).Studied groups had no significant change in PP, SBP, and DBP over time. No significant difference in PP and DBP among studied groups was observed (PP:P = 0.090; DBP:P = 0.063). Pairwise comparisons of PP, SBP, and DBP showed no statistically significant contrast between any 2 studied groups. Interactions of time and treatment were not different among groups.Our results demonstrate patients using metformin got higher PP and SBP over time. Averagely, pulse and blood pressure among groups were not different. Trends of variation in pulse and blood pressure were not different among studied diabetes treatments.

Study of correlation between wall shear stress and elasticity in atherosclerotic carotid arteries

OBJECTIVE

This paper presents the use of the texture matching method to measure the rabbit carotid artery elasticity value of the experimental group and control group respectively. It compares the experimental rabbits, when they are prompted by pathological histology to be at the period of carotid atherosclerosis fatty streaks and fiber plaques, with the control group.

METHODS

We have used ultrasound linear array probe for scanning the rabbit carotid arteries. This allows us to obtain the wall shear stress (WSS) and the elasticity values in the atherosclerotic arteries. Using statistical analysis, we are able to clarify whether the texture matching method can diagnose atherosclerosis at the early stage. We also analyze the rabbit carotid artery elasticity and WSS values to make sure whether there is a correlation between both. Combining the texture matching method with the WSS quantitative analysis in the future can enable better prediction of the occurrence and development of atherosclerosis by using noninvasive medical imaging techniques.

RESULTS

This study has confirmed that from the 2nd to the 10th week, with the development of atherosclerosis, the arterial WSS reduction has a negative correlation with the increasing of artery wall elasticity, which means that as the arterial WSS decreases the arterial wall becomes less elastic. Correlating shear stress with atherosclerosis can clarify that WSS can be used as one of the effective parameters of early diagnosis of atherosclerosis.

CONCLUSION

In summary, we have found that the elasticity value can reflect the degree of atherosclerosis more objectively. Therefore, by using noninvasive imaging, the quantitative analysis of shear stress and combined with texture matching method can assist in the early diagnosis of atherosclerosis.

Hypertensive Disorders in Pregnant Women Receiving Fertility Treatments

Hypertensive disorders (HDs) as the most prevalent medical problem during pregnancy, predispose the patient to a lot of comorbidities and may even cause maternal or fetal death. The rate of infertility has been increasing in recent decades. So, we collected and summarized data about the co-existence of these two entities and found that HDs are somewhat more common in women receiving fertility treatments regardless of pathophysiologic correlation of infer- tility and hypertension or older age and chance of multiple pregnancies.

Correlation between quantitative analysis of wall shear stress and intima-media thickness in atherosclerosis development in carotid arteries

Background

This paper presents quantitative analysis of blood flow shear stress by measuring the carotid arterial wall shear stress (WSS) and the intima-media thickness (IMT) of experimental rabbits fed with high-fat feedstuff on a weekly basis in order to cause atherosclerosis.

Methods

This study is based on establishing an atherosclerosis model of high-fat rabbits, and measuring the rabbits’ common carotid arterial WSS of the experimental group and control group on a weekly basis. Detailed analysis was performed by using WSS quantification.

Results

We have demonstrated small significant difference of rabbit carotid artery WSS between the experimental group and the control group (P<0.01) from the 1st week onwards, while the IMT of experimental group had larger differences from 5th week compared with the control group (P<0.05). Next, we have shown that with increasing blood lipids, the rabbit carotid artery shear stress decreases and the rabbit carotid artery IMT goes up. The decrease of shear stress appears before the start of IMT growth. Furthermore, our receiver operator characteristic (ROC) curve analysis showed that when the mean value of shear stress is 1.198 dyne/cm², the rabbit common carotid atherosclerosis fatty streaks sensitivity is 89.8%, and the specificity is 81.3%. The area under the ROC curve is 0.9283.

Conclusions

All these data goes to show that WSS decreasing to 1.198 dyne/cm² can be used as an indicator that rabbit common carotid artery comes into the period of fibrous plaques. In conclusion, our study is able to find and confirm that the decrease of the arterial WSS can predict the occurrence of atherosclerosis earlier, and offer help for positive clinical intervention.

Metformin: a review of its potential indications

Metformin is the most commonly prescribed drug for type 2 diabetes mellitus. In recent years, in addition to glucose lowering, several studies have presented evidence suggesting some potential role for metformin, such as antitumor effect, antiaging effect, cardiovascular protective effect, neuroprotective effect or an optional treatment for polycystic ovary syndrome. This paper will critically review the role of metformin to provide reference for doctors and researchers.

Metformin effects on the heart and the cardiovascular system: A review of experimental and clinical data

BACKGROUND

Metformin, the eldest and most widely used glucose lowering drug, is likely to be effective also on cardiac and vascular disease prevention. Nonetheless, uncertainty still exists with regard to its effects on the cardiovascular system as a whole and specifically on the myocardium, both at the organ and cellular levels.

METHODS

We reviewed the available data on the cardiac and vascular effects of metformin, encompassing both in vitro, either tissue or isolated organ, and in vivo studies in experimental animals and humans, as well as the evidence generated by major clinical trials.

RESULTS

At the cellular level metformin's produces both AMP-activated kinase (AMPK) dependent and independent effects. At the systemic level, possibly also through other pathways, this drug improves endothelial function, protects from oxidative stress and inflammation, and from the negative effects of angiotensin II. On the myocardium it attenuates ischemia-reperfusion injury and prevents adverse remodeling induced by humoral and hemodynamic factors. The effects on myocardial cell metabolism and contractile function being not evident at rest or in more advanced stages of cardiac dysfunction, could be relevant during transient ischemia, during an acute increase in workload and in the early stages of diabetic/hypertensive cardiomyopathy as confirmed by few small clinical trials and some observational studies. The overall evidence emerging from both clinical trials and real world registry is in favor of a protective effect of metformin with respect to both coronary events and progression to heart failure.

CONCLUSIONS

Given this potential, its efficacy and its safety (and also its low cost) metformin remains the central pillar of the therapy of diabetes.