Treatment of the metabolic disturbances caused by antipsychotic drugs: focus on potential drug interactions

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.

Cardiometabolic comorbidity in antipsychotic treated patients: need for systematic evaluation and treatment

OBJECTIVE

The aim of the study was to determine the prevalence of cardiometabolic dysregulations and their somatic treatment regimens in a group of psychiatric patients treated with antipsychotics.

METHODS

In a naturalistic cohort study, baseline cardiometabolic parameters were measured in 543 outpatients. After one year, a second assessment was performed in 220 patients out of the total sample. In addition, it was investigated whether in patients with somatic comorbidities adequate treatment was prescribed.

RESULTS

In this cohort, about half of the patients fulfilled the criteria for metabolic syndrome. Only a limited number of patients, however, received pharmacologic treatment for individual risk factors: About 19% for hypercholesterolemia, 26% for hypertension, and 52% for diabetes. Non-treated patients were significantly younger than treated patients. Follow-up data show that the course of the cardiometabolic parameters can be dynamic.

CONCLUSIONS

Cardiometabolic risk factors are highly prevalent in psychiatric patients treated with antipsychotic drugs. Unfortunately, adequate treatment of cardiometabolic comorbidity in these relatively young patients is seriously hampered. Thus, specific guidelines for psychiatric patients have to be developed taking into account the high cardiovascular risk at a relatively young age and potential pharmacokinetic interactions between psychotropics and somatic compounds. Moreover, integration of psychiatric and physical health care systems for patients with mental disorders is urgently needed.

Diabetes mellitus in patients with schizophrenia in West-Bank, Palestine

AIMS

The main aims of the study were to investigate the prevalence of pre-diabetes and diabetes mellitus (DM) in patients with schizophrenia, to compare it with those published in the general population, and to assess significant associations with dysglycemia defined as having either pre-DM or DM.

METHODS

A cross-sectional study carried out in 4 governmental primary psychiatric healthcare centers in Northern West-Bank, Palestine. Fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) were measured. The World Health Organization (WHO) criteria for defining pre-DM and DM were used. Dysglycemia was defined as FBG >110mg/dl.

RESULTS

Based on WHO criteria, 27 patients (10.8%) had diabetes and 34 (13.6%) had pre-diabetes. The prevalence of DM in patients with schizophrenia was not significantly higher than that reported in the general population of Palestine. However, the prevalence of pre-DM was significantly higher than that reported in the general population of Palestine. Regression analysis showed that advancing age and abnormal waist circumference were significant predictors of dysglycemia in patients with schizophrenia.

CONCLUSIONS

This study confirmed the high prevalence of dysglycemia in patients with schizophrenia, supporting the need for monitoring of blood glucose in this category of patients. The presence of primary risk factors is more important in the development of dysglycemia in patients with schizophrenia than exposure to antipsychotic drugs.

Pharmacological management of atypical antipsychotic-induced weight gain

Excessive bodyweight gain was reported during the 1950s as an adverse effect of typical antipsychotic drug treatment, but the magnitude of bodyweight gain was found to be higher with the atypical antipsychotic drugs that were introduced after 1990. Clozapine and olanzapine produce the greatest bodyweight gain, ziprasidone and aripiprazole have a neutral influence, and quetiapine and risperidone cause an intermediate effect. In the CATIE study, the percentage of patients with bodyweight gain of >7% compared with baseline differed significantly between the antipsychotic drugs, i.e. 30%, 16%, 14%, 12% and 7% for olanzapine, quetiapine, risperidone, perphenazine (a typical antipsychotic) and ziprasidone, respectively (p<0.001). Appetite stimulation is probably a key cause of bodyweight gain, but genetic polymorphisms modify the bodyweight response during treatment with atypical antipsychotics. In addition to nutritional advice, programmed physical activity, cognitive-behavioural training and atypical antipsychotic switching, pharmacological adjunctive treatments have been assessed to counteract excessive bodyweight gain. In some clinical trials, nizatidine, amantadine, reboxetine, topiramate, sibutramine and metformin proved effective in preventing or reversing atypical antipsychotic-induced bodyweight gain; however, the results are inconclusive since few randomized, placebo-controlled clinical trials have been conducted. Indeed, most studies were short-term trials without adequate statistical power and, in the case of metformin, nizatidine and sibutramine, the results are contradictory. The tolerability profile of these agents is adequate. More studies are needed before formal recommendations on the use of these drugs can be made. Meanwhile, clinicians are advised to use any of these adjunctive treatments according to their individual pharmacological and tolerability profiles, and the patient's personal and family history of bodyweight gain and metabolic dysfunction.

Metformin as an adjunctive treatment to control body weight and metabolic dysfunction during olanzapine administration: a multicentric, double-blind, placebo-controlled trial

BACKGROUND

Excessive body weight gain (BWG) is a clinically relevant side effect of olanzapine administration. The primary objective of this study was to assess whether metformin prevents or reverses BWG in patients with schizophrenia or bipolar disorder under olanzapine administration. Secondarily we evaluated diverse metabolic variables.

METHODS

Eighty patients taking olanzapine (5-20 mg daily for more than 4 consecutive months) were randomly allocated to metformin (n=40; 850 to 2550 mg daily) or placebo (n=40) group in a 12-week double-blind protocol. Waist circumference (WC) body weight (BW), body mass index (BMI) fasting glucose, glycated hemoglobin (Hb1c), insulin, an insulin resistance index (HOMA-IR) lipids, leptin, c-reactive protein, fibrinogen, cortisol and the growth hormone (GH) were evaluated at baseline and at week 12 of treatment.

RESULTS

The metformin group lost 1.4+/-3.2 kg (p=0.01) and tended to decrease its leptin levels, whereas the placebo group maintained a stable weight: -0.18+/-2.8 kg (p=0.7). The HOMA-IR significantly increased after placebo (p=0.006) and did not change after metformin (p=0.8). No ostensible differences were observed in the other variables, even though metformin did not improve the lipid profile and the Hb1c levels.

CONCLUSIONS

Metformin may safely assist olanzapine-treated patients in body weight and carbohydrate metabolism control.