Diabetes and Mental Illness: How Are They Linked?
Diagnoses included schizophrenic or schizoaffective disorders, mood disorders, or substance abuse disorders.
Diabetes appears to be more prevalent in the psychiatric setting than in the general population, according to the results of a recent meta-analysis from the United Kingdom published earlier this year in General Hospital Psychiatry.1 Both inpatients and outpatients with psychiatric conditions were more likely to have a diagnosis of diabetes, or to have impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) than patients without a psychiatric condition.2,3
The investigators evaluated 36 studies from Europe, Asia, and North America involving 42 psychiatric cohorts for the prevalence of multiple impairments of glucose metabolism. Unspecified diabetes was reported in 10% of all patients evaluated from 31 studies (95% CI, range 9-12), while the prevalence of type 1 diabetes was 1% (0-1) and type 2 diabetes was 9% (613) reported in 5 and 13 studies, respectively. The prevalence of IFG was 18% (8-28, 7 studies), and of IGT 22% (16-28, 3 studies). This meant that 1 of every 10 psychiatric patients studied was diagnosed with diabetes, 1 in 5 with IFG, and 1 in 5 with IPG. The prevalence rates did not vary by continent or by type of inpatient setting.
The range of psychiatric diagnoses included schizophrenic or schizoaffective disorders, mood disorders, and substance abuse disorders, with little variation in prevalence of unspecified diabetes by psychiatric category (11% across all inpatient disorders, 95% CI, 10-12).
The etiology of this increased prevalence was not clear, although the investigators suggested that links to antipsychotic medication use in these patients could be a factor.4,5 “The study did not set out to examine the etiology of abnormal glucose metabolism in these patients, but to document its prevalence in these settings,” study co-investigator, Emmert Roberts, MA, BMBCh, MRCP (UK), MRCPsych, DFSRH, of the Institute of Psychiatry, Psychology and Neuroscience at King's College London, in the United Kingdom, told Psychiatry Advisor.
The study findings indicated a need for psychiatrists to give attention to their patients' glucose metabolism status. “We would recommend that routine screening take place in psychiatric inpatient settings for not only diabetes but also pre-diabetic states of abnormal glucose metabolism,” Dr. Roberts said. The researchers contend that such screening would present opportunities for timely intervention with metabolic issues that might be contributing to psychiatric illnesses. “A prevalence of 1 in 5 for IFG or IGT is higher than estimates for number of inpatients with bipolar affective disorder and some personality disorders across all inpatient settings, suggesting that abnormal glucose metabolism should be an essential part of psychiatric postgraduate examination, training and expertise,” they concluded.
- Roberts E, Jones L, Blackman A, et al. The prevalence of diabetes mellitus and abnormal glucose metabolism in the inpatient setting: a systematic review and meta-analysis [published online January 11, 2017]. Gen Hosp Psychiatry doi:10.1016/j.genhosppsych.2017.01.003.
- Global status report on noncommunicable diseases 2014. Geneva:World Health Organization; 2012. www.who.int/nmh/publications/ncd-status-report-2014/en/. Accessed June 30, 2017.
- Vancampfort D, Correll CU, Galling B, et al. Diabetes mellitus in people with schizophrenia, bipolar disorder and major depressive disorder: a systematic review and large scale meta-analysis. World Psychiatry. 2016;15(2):166-174. doi:10.1002/wps.20309
- Galling B, Roldán A, Nielsen RE, et al. Type 2 diabetes mellitus in youth exposed to antipsychotics: a systematic review and meta-analysis. JAMA Psychiat 2016;73(3):247-259. doi:10.1001/jamapsychiatry.2015.2923.
- Leslie DL, Rosenheck RA. Incidence of newly diagnosed diabetes attributable to atypical antipsychotic medications. Am J Psychiatry 2004;161(9):1709-1711. doi:10.1001/jamapsychiatry.2015.2923.