A recent study from Canada finds an elevated risk for diabetes when a person has both depression and metabolic syndrome; the diabetes risk is higher when the two disorders are combined than when only one or the other disorder is present. A second study, from Europe, finds similarly elevated risk for diabetes and other cardiovascular diseases when depression or other psychiatric disorders are present. Both studies suggest the importance of managing risk factors for metabolic disease when mental health suffers.

While depression and other psychiatric disorders aren’t necessarily preventable, metabolic syndrome can be. An effective way to minimize the increased risk for diabetes in middle age, as were the study participants in the Canadian study, is to minimize risk factors for metabolic syndrome in younger adulthood.

Diabetes + Depression
McGill University assistant professor Norbert Schmitz led the Canadian study that involved 2,525 study participants (40 to 69 years old) followed for 4.5 years. The participants were divided into four groups:

  1. With depression plus three or more risk factors for metabolic syndrome.
  2. With depression only.
  3. With metabolic syndrome risk factors only.
  4. Without any symptoms of diabetes or metabolic syndrome risk factors (the reference group).

Risk factors for metabolic syndrome (sometimes called pre-diabetes) include excess weight, especially when it is distributed in the abdominal area; high blood pressure; high blood levels of triglycerides; elevated fasting glucose levels; insulin resistance; and low high-density lipoprotein (HDL, or “good” cholesterol). An estimated 34% of the adult population in the US has metabolic syndrome, which increases the risk of diabetes and cardiovascular diseases.

The Canadian study revealed:

  1. Depression alone produced no more than a slightly increased risk of diabetes than the reference group.
  2. Diabetes is four times more likely (than the reference group) when metabolic syndrome exists.
  3. Diabetes is six times more likely when depression and metabolic syndrome are combined.

In some cases, depression changes the metabolic function to make excess weight, hypertension, and problems with glucose metabolism more likely to develop. A side effect of some antidepressants is weight gain. These factors may contribute to the elevated risk for diabetes when depression and metabolic syndrome are combined but the two disorders may work against each other in a vicious cycle suggested by the findings of both studies.

Mental Health and Physical Well-Being
The European study compared the risk for diabetes, hyperlipidemia (high levels of cholesterol, triglycerides, and other fatty substances in the blood), and obesity between people 30 and older with and without previous diagnoses of psychiatric disorders (depression, bipolar disorder, anxiety, schizophrenia, and personality disorders). The study involved 524,952 patients treated at 140 primary care facilities in London between 2005 and 2015.

This study revealed:

Patients with psychiatric disorders were at increased risk for cardiovascular disease, especially diabetes.
They are also at increased risk for hyperlipidemia and obesity.
Antidepressant use increased the risk for all three metabolic disorders.
Antipsychotic medications increased the risk of diabetes.
Cardiovascular disease is diagnosed later in patients with psychiatric disorders.
In addition to the use of antidepressants and/or antipsychotics as risk factors, the researchers evaluated social deprivation as a risk factor, too, but found no association unless the patient was also a smoker with a sedentary lifestyle.

Vicious Cycle in Play?
People suffering from depression and other mental disorders aren’t always willing or motivated to follow medical advice or maintain lifestyles that promote optimum health. These two studies emphasize the need for increased awareness of diabetes and cardiovascular risk factors associated with psychiatric disorders to reduce the chance of a vicious cycle coming into play between the two disorders. Patients seeking treatment for mental health issues may benefit from education and counseling services that include the importance of taking medications as prescribed, smoking cessation programs, healthy dietary practices, and daily physical exercise.

Sources:

Schmitz, N, et al. "Depression and risk of type 2 diabetes: the potential role of metabolic factors." Nature. Molecular Psychiatry / Nature Publishing Group, Macmillan Publishers Limited, 23 Feb. 2016. Nature.com. Web. 14 Apr. 2016.

Pérez-Piñar, M, et al. "Cardiovascular risk factors among patients with schizophrenia, bipolar, depressive, anxiety, and personality disorders." PubMed. European Psychiatry / European Psychiatric Association (Elsevier), 7 Apr. 2016. US National Library of Medicine / National Institutes of Health. Web. 14 Apr. 2016.