It is of note that two of these R428 studies referred to drug-naïve patients who had been medicated for only 6 weeks with antipsychotic agents, and they developed MetS in response to this [Saddichha et al. 2007, 2008], and the third study referred to a very rare population of drug-naïve, unmedicated patients with an extremely low prevalence of MetS, as discussed above [Padmavati et al. 2010]. A German study explored the prevalence of MetS in patients

with treated or untreated Inhibitors,research,lifescience,medical schizophrenia at baseline and at 3 months after initiation or switch of antipsychotic treatment. The authors reported an increase from 44.3% to 49.6%, and also described the lowest Inhibitors,research,lifescience,medical baseline MetS prevalence (24.7%) in previously unmedicated patients [Kraemer et al. 2011]. The lack of further studies on drug-naïve patients is an anticipated source of

bias in any effort to explore the role of antipsychotic medication in the development of MetS. However, numerous studies attempted to compare various antipsychotics or groups of antipsychotics (FGAs versus SGAs) in terms of their contribution to MetS [Almeras et al. 2004; Kato et al. 2004; Straker et al. 2005; Correll et al. 2006, 2007; Hagg et al. 2006; L’Italien et al. 2007; Suvisaari et al. 2007; Tirupati et al. 2007; Inhibitors,research,lifescience,medical Cerit et al. 2008; De Hert et al. 2008b; Meyer et al. 2008; Saddichha et al. 2008; Huang et al. 2009; Rezaei et al. 2009; Schorr et al. 2009; Lee et al. 2011]. Consistent findings across these studies found that MetS was more likely with SGAs over FGAs, polypharmacy over monopharmacy and high-potency over low-potency agents. Inhibitors,research,lifescience,medical For individual antipsychotics, clozapine

and olanzapine appeared to be related to higher MetS rates than other antipsychotic agents. Metabolic syndrome and ethnicity Inhibitors,research,lifescience,medical Very few studies attempted to address the issue of ethnicity when MetS rates are calculated [Basu et al. 2004; Kato et al. 2004; McEvoy et al. 2005; Straker et al. 2005; Correll et al. 2006; Lamberti et al. 2006]. Black African and Hispanic patients appeared to present with higher rates of MetS, however some studies found rates to be similar to white populations. However, outcomes appeared to be quite inconsistent. It is of note that despite Indian and Asian populations having a predisposition to develop diabetes, studies of patients with schizophrenia nearly originating from these populations usually reported lower prevalence rates of MetS compared with white and black patients. Of course this observation can also reflect the lower rates of prescribing atypical antipsychotics in developing versus developed countries. Metabolic syndrome and duration of pscyhotic illness or type of psychiatric setting Only three studies were identified which looked at duration of psychotic illness in the calculation of MetS rates.