Prevalence of diabetes mellitus in persons with SMI (ages 18 years or older)
Individuals with diabetes (numerator) among individuals with SMI 18 years or older (denominator)
Severe mental illness (SMI) includes schizophrenia, schizoaffective disorders, and bi-polar disorders. Individuals with SMI are at a higher risk of poor physical health and of premature death. It is estimated that for people with SMI, two out of three deaths are from physical illnesses that can be prevented . Cardiovascular disease and cardiovascular risk factors are more common in people with SMI compared with the general population. For instance, the prevalence of obesity is 1.5-2 fold higher in persons with SMI compared with the general population, and the prevalence of diabetes is 2-3 times higher. Additionally, the age of diabetes onset is earlier in persons with SMI, and the incidence and severity of complications are higher as well, including micro- and macro-vascular complications, acute metabolic dysregulation, and diabetes-associated mortality. The underlying mechanisms relating cardiovascular risk factors and SMI are complex, and include genetic, environmental, and behavioral aspects, as well as aspects related to anti-psychotic drug therapy .
Individuals in the denominator with diabetes according to one or more of the following criteria: (a) Plasma glucose level >200 mg% in at least two tests in the year prior to the measurement year (minimal 30-day interval is required between tests); (b) HbA1c >6.5% at least once in the year prior to the measurement year; (c) at least three prescriptions of diabetes medications being dispensed during the year prior to the measurement year.
Individuals with SMI 18 years or older
 Severe mental illness (SMI) and physical health inequalities: briefing. Public Heath England, September 2018. Available at: https://www.gov.uk/government/publications/severe-mental-illness-smi-physical-health-inequalities/severe-mental-illness-and-physical-health-inequalities-briefing
 Holt RI, Mitchell AJ, Diabetes mellitus and severe mental illness: mechanisms and clinical implications. Nat Rev Endocrinol. 2015 Feb;11(2):79-89