Diabetes, prediabetes, and suicide deaths in a Japanese working population

Association between suicidal behavior and impaired glucose metabolism in first-episode drug-naïve patients with schizophrenia

BACKGROUND

Schizophrenia (SZ) patients have been reported to have comorbid suicidal behavior (SB) and impaired glucose metabolism in early psychosis, but it is unclear whether impaired glucose metabolism plays a role in the occurrence of SB in patients with first-episode drug-naïve (FEDN) SZ. Therefore, our main aim was to examine the relationship between SB and glucose metabolism in FEDN SZ patients.

METHODS

We recruited 319 FEDN SZ patients and collected information on their sociodemographic characteristics, clinical data, and glucose metabolism parameters. Participants' psychotic and depressive symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Hamilton Depression Rating Scale (HAMD), respectively. Fasting plasma glucose and insulin levels were also measured.

RESULTS

The percentage of FEDN SZ patients with SB was 45.5% (145/319). Compared to SZ patients without SB, SZ patients with SB exhibited higher scores on HAMD, PANSS positive subscale, as well as higher levels of fasting plasma glucose, fasting plasma insulin, and homeostasis model assessment of insulin resistance index (all p<0.05). Logistic regression analysis indicated that increased levels of insulin resistance (adjusted OR = 1.920), body mass index (adjusted OR = 0.931), and PANSS general psychopathology (adjusted OR = 1.041) were independently associated with SB. The Receiver Operating Characteristic Curve showed an Area Under Curve value of 0.732 for the combination of three factors in regression model to distinguish between SB and non-SB.

CONCLUSIONS

Our results indicate that fasting glucose, fasting insulin, and insulin resistance are strongly associated with SB in FEDN SZ patients, suggesting that glucose metabolism abnormalities may be potential biomarkers of SB in SZ patients. Regular monitoring of glucose metabolism variables is essential for suicide prevention.

Prevention of suicidal behavior in diabetes: the role of primary care

Studies in different countries suggest that the rates of suicide ideation, attempts and death are increased in patients with diabetes in comparison to the general population. Suicidal behavior in patients with diabetes is a significant but underappreciated problem. Elevated suicide risk in individuals with diabetes may be related to comorbid psychiatric disorders, particularly depression. Considerable evidence suggests a bidirectional relationship between diabetes and depression: individuals with diabetes are at elevated risk of developing depression and patients with depression are more likely to develop diabetes. Frequent comorbidity of diabetes and depression may be related to psychosocial and neurobiological factors. Other comorbid psychiatric conditions including anxiety and alcohol use disorders may also increase suicide risk in diabetes. Primary care physicians are likely the key to suicide prevention efforts in individuals with diabetes since they see almost half of individuals who die by suicide within 1 month of their suicide. The management of potentially suicidal patients with diabetes in primary care comprises six major components: management of diabetes and its complications, especially conditions associated with pain; diagnosis and treatment of comorbid psychiatric disorders; frequent assessment of suicide risk; restricting access to the means of suicide; specific treatments to reduce the predisposition to attempt suicide; and referral to psychiatric care. Suicide prevention in individuals with diabetes and other medical disorders is a difficult but critically important task.