The adjunctive use of metformin to treat or prevent atypical antipsychotic-induced weight gain: a review

Metformin and insulin-resistant related diseases: Emphasis on the role of microRNAs

Metformin is one of the most prescribed drugs in type II diabetes (T2DM) which has recently found new applications in the prevention and treatment of various illnesses, from metabolic disorders to cardiovascular and age-related diseases. Metformin improves insulin resistance (IR) by modulating metabolic mechanisms and mitochondrial biogenesis. Alternation of microRNAs (miRs) in the treatment of IR-related illnesses has been observed by metformin therapy. MiRs are small non-coding RNAs that play important roles in RNA silencing, targeting the 3'untranslated region (3'UTR) of most mRNAs and inhibiting the translation of related proteins. As a result, their dysregulation is associated with many diseases. Metformin may alter miRs levels in the treatment of various diseases by AMPK-dependent or AMPK-independent mechanisms. Here, we summarized the therapeutic role of metformin by modifying the aberrant expression of miRs as potential biomarkers or therapeutic targets in diseases in which IR plays a key role.

New insight for metformin against bladder cancer

International Agency for Research on Cancer (IARC) estimated that bladder cancer is the ninth most common cancer in the world, with 430,000 new cases and 165,000 deaths in 2012. Bladder cancer represents the fourth most common cancer in men and ninth most common cancer in women. It is the second most prevalent cancer in men 60 years of age or older in United States. Looking further down, continuing advancements in cancer research could potentially offer more choices for clinician and patient with longer survival and better quality of life. Although, bladder cancer represents an ideal tumor model to test and apply cancer prevention strategies; there are limited studies about application of metformin in the management of bladder cancer. Here, I will shed light on the proposed mechanisms of anti-carcinogenic effects of metformin and cohort of these mechanisms with the novel application of metformin as therapy of bladder cancer.

Efficacy and safety of adjunctive topiramate for schizophrenia: a meta-analysis of randomized controlled trials

OBJECTIVE

To systematically examine the randomized controlled trial (RCT) evidence regarding efficacy and tolerability of topiramate cotreatment with antipsychotics in schizophrenia-spectrum disorders.

METHODS

Random-effects meta-analysis of RCTs of topiramate cotreatment with antipsychotics vs. placebo/ongoing antipsychotic treatment in schizophrenia-spectrum disorders. Standardized or weighted mean difference (SMD/WMD), risk ratio (RR) ±95% confidence intervals (CIs), and number needed to harm (NNH) were calculated.

RESULTS

Across 16 RCTs (n = 934, duration = 11.8 ± 5.6 weeks), topiramate outperformed the comparator regarding change/endpoint of total (SMD: -0.58, 95% CI: -0.82, -0.35, P < 0.00001), positive (SMD: -0.37, 95% CI: -0.61, -0.14, P = 0.002), negative (SMD: -0.58, 95% CI: -0.87, -0.29, P < 0.0001), and general symptoms (SMD: -0.68, 95% CI: -0.95, -0.40, P < 0.00001). Furthermore, topiramate was superior regarding body weight (WMD: -2.75 kg, 95% CI: -4.03, -1.47, P < 0.0001), body mass index (BMI) (WMD: -1.77, 95% CI: -2.38, -1.15, P < 0.00001), triglycerides (P = 0.006), and insulin levels (P < 0.00001). Superiority regarding psychopathology and body weight/BMI was consistent across Chinese/Asian and Western RCTs, double-blind and open designs, clozapine and non-clozapine cotreatment, augmentation and co-initiation RCTs, and higher and lower quality RCTs. In meta-regression analyses, topiramate's efficacy for total symptoms was moderated by shorter illness duration (P = 0.047), while weight loss was greater in prevention/co-initiation vs. intervention/augmentation RCTs (-4.11 kg, 95% CI: -6.70, -1.52 vs. -1.41 kg, 95% CI: -2.23, -0.59, P < 0.001). All-cause discontinuation was similar between topiramate and comparators (RR: 1.28, 95% CI: 0.91, 1.81, P = 0.16). While topiramate led to more concentration/attention difficulties (P = 0.03, NNH = 8, 95% CI=4-25), psychomotor slowing (P = 0.02, NNH = 7, 95% CI = 4-25), and paresthesia (P = 0.05, NNH = 2, 95% CI = 4-33), it led to less ≥7% weight gain (P = 0.0001, NNH = 2, 95% CI = 2-3) and constipation (P = 0.04, NNH = 9, 95% CI = 5-100) than the comparator.

CONCLUSIONS

These results indicate that adjunctive topiramate to antipsychotics is an effective and safe treatment choice for symptomatic improvement and weight reduction in patients with schizophrenia-spectrum disorders.

Phase II study of metformin for reduction of obesity-associated breast cancer risk: a randomized controlled trial protocol

Background

Two-thirds of U.S. adult women are overweight or obese. High body mass index (BMI) and adult weight gain are risk factors for a number of chronic diseases, including postmenopausal breast cancer. The higher postmenopausal breast cancer risk in women with elevated BMI is likely to be attributable to related metabolic disturbances including altered circulating sex steroid hormones and adipokines, elevated pro-inflammatory cytokines, and insulin resistance. Metformin is a widely used antidiabetic drug that has demonstrated favorable effects on metabolic disturbances and as such may lead to lower breast cancer risk in obese women. Further, the anti-proliferative effects of metformin suggest it may decrease breast density, an accepted biomarker of breast cancer risk.

Methods/design

This is a Phase II randomized, double-blind, placebo-controlled trial of metformin in overweight/obese premenopausal women who have elements of metabolic syndrome. Eligible participants will be randomized to receive metformin 850 mg BID (n = 75) or placebo (n = 75) for 12 months. The primary endpoint is change in breast density, based on magnetic resonance imaging (MRI) acquired fat-water features. Secondary outcomes include changes in serum insulin levels, serum insulin-like growth factor (IGF)-1 to insulin-like growth factor binding protein (IGFBP)-3 ratio, serum IGF-2 levels, serum testosterone levels, serum leptin to adiponectin ratio, body weight, and waist circumference. Exploratory outcomes include changes in metabolomic profiles in plasma and nipple aspirate fluid. Changes in tissue architecture as well as cellular and molecular targets in breast tissue collected in a subgroup of participants will also be explored.

Discussion

The study will evaluate whether metformin can result in favorable changes in breast density, select proteins and hormones, products of body metabolism, and body weight and composition. The study should help determine the potential breast cancer preventive activity of metformin in a growing population at risk for multiple diseases.

Trial registration

ClinicalTrials.gov Identifier: NCT02028221. Registered on January 2, 2014. Grant #: 1R01CA172444-01A1 awarded on Sept 11, 2013.

Cancer screening, prevention, and treatment in people with mental illness

People with mental illness die decades earlier in the United States compared with the general population. Most of this disparity is related to preventable and treatable chronic conditions, with many studies finding cancer as the second leading cause of death. Individual lifestyle factors, such as smoking or limited adherence to treatment, are often cited as highly significant issues in shaping risk among persons with mental illness. However, many contextual or systems-level factors exacerbate these individual factors and may fundamentally drive health disparities among people with mental illness. The authors conducted an integrative review to summarize the empirical literature on cancer prevention, screening, and treatment for people with mental illness. Although multiple interventions are being developed and tested to address tobacco dependence and obesity in these populations, the evidence for effectiveness is quite limited, and essentially all prevention interventions focus at the individual level. This review identified only one published article describing evidence-based interventions to promote cancer screening and improve cancer treatment in people with mental illness. On the basis of a literature review and the experience and expertise of the authors, each section in this article concludes with suggestions at the individual, interpersonal, organizational, community, and policy levels that may improve cancer prevention, screening, and treatment in people with mental illness.

Metformin for Weight Gain and Metabolic Abnormalities Associated With Antipsychotic Treatment: Meta-Analysis of Randomized Placebo-Controlled Trials

This meta-analysis examined the effectiveness and safety of metformin to prevent or treat weight gain and metabolic abnormalities associated with antipsychotic drugs. We systematically searched in both English- and Chinese-language databases for metformin randomized controlled clinical trials (RCTs) using placebo in patients taking antipsychotics. Twenty-one RCTs (11 published in English and 10 in Chinese) involving 1547 subjects (778 on metformin, 769 on placebo) were included in this meta-analysis. Metformin was significantly superior to placebo (standard mean differences, -0.69 to -0.51; P = 0.01-0.0001) in the primary outcome measures (body weight, body mass index, fasting glucose, fasting insulin, triglycerides, and total cholesterol). Metformin was significantly superior to placebo in some secondary outcome measures but not in others. Significantly higher frequencies of nausea/vomiting and diarrhea were found in the metformin group, but no differences were found in other adverse drug reactions. In the metformin group, the frequency of nausea/vomiting was 14%, and of diarrhea, 7%. Subgroup and sensitivity analyses demonstrated that primary outcomes were influenced by ethnicity, treatment style (intervention vs prevention), metformin dose, study duration, and mean age. Body weight standard mean difference was -0.91 (confidence interval [CI], -1.40 to -0.41) in 3 prevention RCTs in naive patients, -0.66 (CI, -1.02 to -0.30) in 5 intervention RCTs during the first year, and -0.50 (CI, -0.73 to -0.27) in 9 intervention RCTs in chronic patients. This meta-analysis suggests that adjunctive metformin is an effective, safe, and reasonable choice for antipsychotic-induced weight gain and metabolic abnormalities.

An overview of diabetes management in schizophrenia patients: office based strategies for primary care practitioners and endocrinologists

Diabetes is common and seen in one in five patients with schizophrenia. It is more prevalent than in the general population and contributes to the increased morbidity and shortened lifespan seen in this population. However, screening and treatment for diabetes and other metabolic conditions remain poor for these patients. Multiple factors including genetic risk, neurobiologic mechanisms, psychotropic medications, and environmental factors contribute to the increased prevalence of diabetes. Primary care physicians should be aware of adverse effects of psychotropic medications that can cause or exacerbate diabetes and its complications. Management of diabetes requires physicians to tailor treatment recommendations to address special needs of this population. In addition to behavioral interventions, medications such as metformin have shown promise in attenuating weight loss and preventing hyperglycemia in those patients being treated with antipsychotic medications. Targeted diabetes prevention and treatment is critical in patients with schizophrenia and evidence-based interventions should be considered early in the course of treatment. This paper reviews the prevalence, etiology, and treatment of diabetes in schizophrenia and outlines office based interventions for physicians treating this vulnerable population.

Investigation of molecular serum profiles associated with predisposition to antipsychotic-induced weight gain

OBJECTIVES

Metabolic disturbances are major adverse side effects in the treatment of schizophrenia patients with antipsychotics. A substantial proportion of patients discontinue treatment with second-generation antipsychotics due to weight gain. The objective of this study was to investigate molecular factors predisposing patients to the development of such metabolic disturbances.

METHODS

We investigated whether serum molecules measured before treatment initiation were associated with subsequent weight gain following a 6-week treatment with antipsychotics. The concentrations of 191 molecules were measured longitudinally in serum from 77 schizophrenia patients using multiplex immunoassays.

RESULTS

This showed that the levels of 10 serum molecules at T0 were significantly associated with ΔBMI, which included interleukin-6 receptor, epidermal growth factor and thyroid stimulating hormone.

CONCLUSIONS

Our results suggest that patients who experience antipsychotic-induced weight gain have specific molecular alterations already prior to treatment. Further studies are required to validate and evaluate current findings in the context of response and side-effect development. This may ultimately lead to molecular tests that can aid in the selection of antipsychotic treatments.

Obesity, cardiovascular disease and type 2 diabetes in people with a mental illness: a need for primary health care

People with a mental illness show a growing incidence of obesity, and higher rates of metabolic syndrome when compared with the general population. This paper reviews research on obesity, cardiovascular disease and type 2 diabetes, with the aim of directing clinical attention towards the improvement of patient physical health. A systematic search of cross-discipline databases and journals provided peer-reviewed research for analysis, and national statistics allowed for the investigation of differences in rates of occurrence between people experiencing a mental illness and the general population. Treatment effects via psychotropic medications and lifestyle factors such as poor diet and low levels of exercise suggest that ongoing monitoring is necessary to prevent major physical disorders in people experiencing a mental illness. To aid clinicians, a comprehensive set of clinical guidelines have been developed for the physical assessment and ongoing monitoring of mental health patients.

Metformin and its clinical use: new insights for an old drug in clinical practice

Metformin is generally recommended as first-line treatment in type 2 diabetes, especially in overweight patients, but in recent years new indications for its use have emerged. Metformin has been found to be safe and efficacious both as monotherapy and in combination with all oral antidiabetic agents and insulins. If metformin use during pregnancy and the lactation period is supported by few data, it could be indicated for women with polycystic ovary syndrome, since it could diminish circulating androgens and insulin resistance, thus ameliorating the ovulation rate. Metformin seems to reduce cancer risk, which appears to be increased in diabetics, and is a promising agent for oncoprevention and chemotherapy combinations. Moreover, metformin could find a place in the treatment of non-alcoholic fatty liver disease. Lactic acidosis could be decreased by avoiding metformin use in patients with hypovolemia, sepsis, renal impairment, hypoxic respiratory diseases and heart failure, in the preoperative period and before intravenous injection of contrast media.