T2D with earlier onset linked to mental illness, more hospital stays
Hong Kong researchers have identified “a previously unknown burden” of mental illness among those with young-onset type 2 diabetes (YOD), with a study suggesting more than one-third of days those patients spend in the hospital before age 40 can be attributed to mental health.
Previous reports have linked type 2 diabetes (T2D) and depression, but the magnitude of serious mental illness in individuals with early onset of the condition hadn’t previously been described.
In this study, Calvin Ke, MD, and colleagues followed two T2D diabetes cohorts using Hong Kong health records databases. A population-based cohort of 422,908 individuals was followed for a median of 6.1 years, while a registry-based cohort of 20,866 people was followed for a median of 10.6 years. The authors sought to analyze all-cause and cause-specific hospitalization rates among both YOD—those diagnosed before age 40—and type 2 diabetics who developed the condition later, defined as usual-onset T2D.
In the registry-based cohort, 36.8 percent of hospital bed days among YOD before age 40 were linked to mental illness. Psychotic and mood disorders accounted for 55.1 percent and 31.4 percent of hospital days related to mental illness, respectively.
“Hyperglycemia, which is worse in YOD, may cause neuroinflammation, which in turn increases risk for depression, schizophrenia, and other psychiatric disorders,” Ke, with the Chinese University of Hong Kong and the University of Toronto, and co-authors wrote in the Annals of Internal Medicine. “Diabetes may alter brain connectivity and cause cognitive dysfunction, which may worsen schizophrenia.”
After the age of 60, cardiovascular disease caused the most hospitalizations both in patients with YOD (25.8 percent of bed days) and usual-onset T2D (20 percent).
Based on the observed hospitalization rates, the researchers estimated people with YOD would spend 97 days in the hospital before reaching age 75. However, a model estimated they could reduce that figure by about one-third—to 65 days—by stopping smoking and keeping their blood glucose, systolic blood pressure, LDL cholesterol and triglyceride levels in check. Delaying onset of T2D until after age 40 further reduced the cumulative hospital days to 47.
“We found a previously unknown burden of serious mental illness before age 40 years, and understanding its causes is imperative to improving mental health care in young adults,” Ke et al. wrote. “Compared with patients with usual-onset T2D, those with YOD had, on average, double the hospitalization rate by age 60 years for any cause, including cardiovascular events, renal complications (for which the rate was 7 times higher), diabetes, and infections.
“These increased rates reveal the disproportionate effects of increased disease duration and glycemic burden in YOD and challenge the perception that youth protects against hospitalization.”
The researchers called for comprehensive assessments of YOD patients’ physical and psychological health, as well as the optimization of risk factors that could limit their future hospital days and reduce the costly effects of diabetes-related complications on patients, their employers and the health system.
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.