Obesity in Schizophrenia

Over the last three decades, an epidemic of obesity has markedly affected patients suffering from mental illnesses such as schizophrenia. Antipsychotic medications used to treat schizophrenia are considered as major culprits. The aim of this review is to first consider risk factors, to then outline negative sequelae of obesity for this population, and finally to address timing and content of recommended clinical interventions. Medical databases were searched with the terms “”weight,” “obesity,” and “schizophrenia.” Selection of articles was guided by date of publication; recent papers are preferentially cited. The main findings were that, in addition to antipsychotic medications, socio-economics, lifestyle, immune factors, and circadian rhythms also contribute to obesity risk. A barrier to effective health promotion within psychiatry has been the concern that fears about gaining weight might stop individuals with schizophrenia from taking needed antipsychotic medication. Recommendations, therefore, are to keep the dose of antipsychotic medication as low as possible, avoid polypharmacy, encourage healthy eating and physical activity, address sleep problems and substance use, monitor weight, blood pressure, and metabolic parameters regularly, utilize motivational interviewing techniques and peer support, pay special attention to special needs such as those of women during pregnancy, and include bariatric surgery as a potential intervention. Conclusion: Besides careful attention to medication regimens, the literature supports the active encouragement and support of patient self-management strategies to both prevent and manage obesity in schizophrenia. DOI : 10.14302/issn.2574-450X.jom-16-1039 Corresponding Author: Mary V. Seeman, Professor Emerita, Department of Psychiatry, University of Toronto, 260 Heath Street W. Toronto, Ontario, Canada M5P 3L6. 1 416 486 3456 mary.seeman@utoronto.ca


Introduction
Historically, schizophrenia, the diagnostic term for a severe, but treatable, brain disorder that affects 1% of the world's population and is characterized by hallucinations, delusions, disordered thinking, apathy, and cognitive deterioration, has always been linked to an asthenic (slender) body build (1). As a recent example, in a population-based cohort study of men born in Sweden between 1952 and 1982, those who subsequently developed schizophrenia had an initially lower body mass index than their peers. In fact, the men who were underweight (under 18.5 BMI) had a 30% increased risk of developing schizophrenia compared to their peers (2). And yet, today, in developed countries, schizophrenia has become closely associated with obesity, most markedly so since the 1990s, the time at which second-generation

Method
The multidisciplinary Google Scholar database was searched with the terms ""weight," "obesity," and "schizophrenia." The literature on this topic is voluminous. Selection of articles was guided by date of publication; recent papers are preferentially cited.

Prevalence
Individuals diagnosed with schizophrenia have a 2.8 to 3.5 increased likelihood over that of the general population of being obese (body mass index of 30 or higher) (6). Both women and men with schizophrenia develop a central form of obesity with enlarged waist circumferences (7).

Lifestyle
Because the spike in obesity in this population correlates in time with the introduction of secondgeneration antipsychotic drugs, these agents are rightly considered to be major causal contributors to the phenomenon. During the same time period, however, obesity rates also rose in the general population not because of drugs but because of the proliferation and ready availability of calorie-rich foods and an increasingly sedentary urban lifestyle (8,9)  This is an interesting association between schizophrenia and asthenic build and suggests that it is probably not genetics that makes individuals with schizophrenia tend toward obesity but, rather, lifestyle and the medication they take. Antipsychotics are not the only psychotropic medications that induce weight gain. As mentioned earlier, many people with schizophrenia suffer from comorbid depression (18) for which they are commonly treated with antidepressants and mood stabilizers, which also have weight-inducing potential (37).

Other Potential Risks for Obesity in Schizophrenia
Circadian Rhythm Impairment

Sequelae of Obesity
The negative health consequences of high BMI are mediated by raised blood pressure, disturbances in glucose metabolism, and adverse lipid profiles (48).
Obesity constitutes a major risk factor for type 2 diabetes, to which people with schizophrenia seem particularly prone (see genetic factors above). It has been found that, even in first-episode, drug-naïve patients with schizophrenia, 15% show impaired fasting glucose tolerance, are more insulin resistant and have higher levels of plasma glucose, insulin, and cortisol than healthy comparison subjects. This may be due to shared predisposing genes between schizophrenia and diabetes, or to the stress inherent in this illness (49).
Obesity is a major factor in the metabolic syndrome (50,51) and in cardiovascular problems (52)

Management of Obesity in Schizophrenia
The management of weight gain and obesity in patients with schizophrenia frequent monitoring, early recognition, and multidisciplinary treatment (63).
The strategies are essentially the same as they are in the general population (64)