Table of Contents  
Year : 2013  |  Volume : 4  |  Issue : 3  |  Page : 174-175  

The metabolic syndrome and schizophrenia: A comorbidity or an association?

Department of Psychiatry, Saint Joseph University, Beirut, Psychiatric Hospital of the Cross, Jalledib, Lebanon

Date of Web Publication5-Jul-2013

Correspondence Address:
Rami Bou khalil
Psychiatric Hospital of the Cross, Jalledib (P.O. box: 60096)
Rami Bou khalil
Psychiatric Hospital of the Cross, Jalledib (P.O. box: 60096)
Login to access the Email id

Source of Support: None, Conflict of Interest: None

PMID: 23960421

Rights and PermissionsRights and Permissions

How to cite this article:
khalil RB, khalil RB. The metabolic syndrome and schizophrenia: A comorbidity or an association?. J Pharmacol Pharmacother 2013;4:174-5

How to cite this URL:
khalil RB, khalil RB. The metabolic syndrome and schizophrenia: A comorbidity or an association?. J Pharmacol Pharmacother [serial online] 2013 [cited 2022 Jan 21];4:174-5. Available from:

Individuals with schizophrenia have 2-3 times higher rates of mortality than the general population. Causes of excessive mortality are increased suicide rates and mortality of natural causes such as cardiovascular events. [1] During the last two decades, there has been an increase in the schizophrenia literature discussing the high prevalence of type II diabetes mellitus and pre-diabetic states such as the metabolic syndrome with a consistent pattern of increased metabolic syndrome prevalence in patients suffering from chronic schizophrenia. [2] Patients suffering from schizophrenia seem to be more prone to have an abdominal obesity, an excess of circulating cortisol as a consequence of their central obesity, and an increased risk of developing insulin resistance. In addition, their reaction to continuous stress hyper-activates their hypothalamo-pituitary-adrenal axis. Moreover, some genetic features might be commonly shared by both schizophrenia and metabolic syndrome. Nevertheless, the lifestyle of patients with schizophrenia is accompanied with risk factors that may increase the risk of development of a metabolic syndrome or aggravate its evolution. Those lifestyle components are excessive sedentarism, excessive smoking, low socio-economic status, low adherence to medical care, etc. [3]

According to a large number of studies, patients suffering from schizophrenia for which they receive antipsychotic drugs are at an increased risk of developing a metabolic syndrome than the general population as well as than other drug-naïve schizophrenia patients. The overall prevalence of metabolic syndrome in those patients is 32.5%. [4] The exact mechanism of metabolic syndrome's risk augmentation, because of antipsychotic drugs intake, is still not well elucidated despite some hypotheses regarding their central and peripheral antagonism of some receptors such as the histaminergic, serotoninergic, and muscarinic ones. [5] The risk of metabolic syndrome induction in patients with schizophrenia seems to be increased by every class of antipsychotic drugs administered, with atypical drugs being more risky than typical antipsychotic drugs. Among atypical antipsychotic drugs, clozapine and olanzapine seem to impose the highest risk of metabolic syndrome induction. The combination of several antipsychotic drugs or any other form of psychopharmacologic drugs combination seems to impose a higher risk as well. Despite expected controversies, some patient-related risk factors for the development of metabolic syndrome in patients with schizophrenia receiving atypical antipsychotic drugs are found in the literature. These, non-exhaustively, include: Age (whether higher or lower), body mass index, family history of obesity, cannabis abuse, gender (whether male or female), ethnicity and socio-cultural lifestyle aspects, etc. [6],[7]

The severity of schizophrenia symptoms especially when it concerns negative and cognitive symptoms might hypothetically be related to an increase in metabolic syndrome's risk under antipsychotic drugs, since the persistence of these symptoms alters patients' adherence to any medical recommendations while also aggravating the patient's metabolic syndrome-predisposing lifestyle. The clinical severity of schizophrenia as a risk factor of metabolic syndrome in patients receiving antipsychotic drugs has not been sufficiently investigated in the medical literature. In this regard, the benefit residing behind the administration of any type of antipsychotic drugs seems to remain superior to the cardio-metabolic risk imposed by these drugs not only because of the risk reduction of other schizophrenia-related causes of mortality such as completed suicide, but also, speculatively because of improvement in the clinical severity of the mental disorder. [8]

To date, the nature of the relationship between schizophrenia and the metabolic syndrome consists of an association between both diseases although many arguments are in favor of comorbidity. In order to clearly determine whether the metabolic syndrome is a comorbidity of schizophrenia, in other words, whether patients with schizophrenia are predisposed after years of development of their mental disorder (since theoretically schizophrenia has the lower age of onset) to develop a metabolic syndrome despite being treated or not with antipsychotic drugs, prospective studies considering patients with schizophrenia not treated with any antipsychotic drug, need to be designed. Intuitively, this kind of study design is challenged by some serious ethical considerations.

In this issue of the "Journal of Pharmacology and Pharmacotherapeutics", Chadda et al. [9] present a comprehensive review of the literature concerning studies related to the domain of metabolic syndrome or any of its components, in drug-naïve and antipsychotic drug-treated patients suffering from schizophrenia. The most important finding of this review resides in the fact that it clearly demonstrates how the metabolic syndrome prevalence increases between drug-naïve patients and antipsychotic treated patients [see metabolic syndrome prevalence in Table 1 in the review of Chadda et al. and compare it with post-treatment prevalence available in the same table and in Table 2 of the same review]. This finding highlights the fact that any patient suffering from schizophrenia and receiving an antipsychotic drug should be considered as a patient who is at risk for the development of a cardiovascular disease or a type II diabetes mellitus unless proven otherwise, that is, until his metabolic profile has been determined and found to be reassuring.

   References Top

1.Auquier P, Lançon C, Rouillon F, Lader M, Holmes C. Mortality in schizophrenia. Pharmacoepidemiol Drug Saf 2006;15:873-9.  Back to cited text no. 1
2.Meyer JM, Stahl SM. The metabolic syndrome and schizophrenia. Acta Psychiatr Scand 2009;119:4-14.  Back to cited text no. 2
3.Bou Khalil R. Metabolic syndrome in patients with schizophrenia independently from atypical antipsychotics intake. Presse Med 2012;41:e238-43.  Back to cited text no. 3
4.Mitchell AJ, Vancampfort D, Sweers K, van Winkel R, Yu W, De Hert M.Prevalence of Metabolic Syndrome and Metabolic Abnormalities in Schizophrenia and Related Disorders: A Systematic Review and Meta-Analysis.Schizophr Bull2011; Dec 29. [Epub ahead of print].  Back to cited text no. 4
5.O'Neill MF. Study focuses in on potential cause of antipsychotic-induced diabetes. Drug News Perspect 2005;18:481-2.  Back to cited text no. 5
6.De Hert M, Dekker JM, Wood D, Kahl KG, Holt RI, Möller HJ. Cardiovascular disease and diabetes in people with severe mental illness position statement from the European Psychiatric Association (EPA), supported by the European Association for the Study of Diabetes (EASD) and the European Society of Cardiology (ESC). Eur Psychiatry 2009;24:412-24.  Back to cited text no. 6
7.Bou Khalil R. Atypical antipsychotic drugs, schizophrenia, and metabolic syndrome in non-Euro-American societies. Clin Neuropharmacol 2012;35:141-7.  Back to cited text no. 7
8.Tiihonen J, Lönnqvist J, Wahlbeck K, Klaukka T, Niskanen L, Tanskanen A, et al. 11-year follow-up of mortality in patients with schizophrenia: A population-based cohort study (FIN11 study). Lancet 2009;374:620-7.  Back to cited text no. 8
9.Chadda RK, Ramshankar P, Deb KS, Sood M. Metabolic syndrome in schizophrenia: Differences between antipsychotic-naïve and treated patients. J Pharmacol Pharmacother 2013;4:174-84  Back to cited text no. 9

This article has been cited by
1 The metabolic syndrome and schizophrenia: A comorbidity or an association?
Khalil, R.
Journal of Pharmacology and Pharmacotherapeutics. 2013; 4(3): 190-191


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article

 Article Access Statistics
    PDF Downloaded308    
    Comments [Add]    
    Cited by others 1    

Recommend this journal