Insulin Resistance May Increase Risk of Depressive Disorder, Research Shows

The negative impacts of insulin resistance on physical health have long been discussed. A study published in the American Journal of Psychiatry found that insulin resistance was associated with more than double the risk of major depressive disorder.

Research continues to demonstrate how chronic physical health conditions are associated with depression, so mental health support is needed.

Understanding the Research

This longitudinal study was conducted in the Netherlands with 601 participants between the ages of 18 and 65, without any prior history of depression or anxiety, based on the DSM-IV criteria.

Researchers found that the development of insulin resistance, based on fasting glucose levels over 2 years was predictive of new major depressive disorder, while the high triglyceride-HDL ratio for cholesterol levels and high waist circumference did not have a significant impact on depression.

These findings support the value of checking the insulin sensitivity of patients but a limitation of this study is that it was restricted to participants who spoke Dutch, so more diverse samples may yield further insights.

Managing the Risk of Depression

Licensed psychologist, clinical researcher, and vice-president of behavioral science at One Drop, Harpreet Nagra, PhD, says, “It’s well-established in the literature that people living with diabetes, including prediabetes, T1D, T2D, and [gestational diabetes] are at higher risk for depression and anxiety.”

Nagra explains that such research helps to underscore the need for better mental health support among people navigating insulin resistance, as it requires time, energy, and attention. Upon receiving a diabetes diagnosis due to insulin resistance, Nagra highlights how they may experience diabetes distress and diabetes burnout. “Understanding the reasons behind the increased risk for mental health challenges are critical to understanding how to effectively treat the mental health of people with diabetes,” she says.

Nagra explains, “While a person may be at higher risk for depression, adequate but ‘not perfect’ management can curb that risk. This means that as long as efforts to improve lifestyle behaviors that would reduce diabetes-related distress (e.g., physical activity, proper nutrition, and ongoing diabetes self-management) are made, depressive disorders can be managed. Genetic factors, however, play a more distinct role. It is still possible to give a person, who is at higher genetic risk to develop depressive disorders with diabetes, the tools they need to combat the condition as long as they are willing to practice them on an ongoing basis.”

Since management of a chronic condition can include burnout, Nagra describes it as a journey that is unique for each person. Given challenges with insulin resistance, Nagra says it is imperative for individuals to be armed with robust resources to manage the mental health risks. “With the proper array of resources for people with diabetes, we can help to manage, and even prevent mental health challenges from escalating,” she says.

Nagra highlights how such research can prompt discussions with individuals navigating insulin resistance about using stress management tools, as well as working with a health coach or therapist if they are interested in referrals. “It’s important to give people with diabetes hope that studies like this indicate higher risk. Risk is different from a definitive outcome that depressive disorder will occur,” she says.

Addressing Insulin Resistance

Adult and geriatric psychiatrist and director of the Pacific Neuroscience Institute’s Pacific Brain Health Center at Providence Saint John’s Health Center, David A. Merrill, MD, PhD, says, “Readers should take away that their physical health significantly impacts their mental well-being over time. Developing insulin resistance more than doubles the odds of having depression in the years ahead.”

Dr. Merrill highlights that insulin resistance is preventable, and also reversible once recognized, which is why he recommends that physicians should be checking their patients’ insulin sensitivity to prevent depression. “When patients are found to have insulin resistance, we need to make it a priority to reverse this condition to prevent not only diabetes but also depression,” he says.

Dr. Merrill explains, “Diabetes is known to increase the risk for depression, dementia, cardiovascular and cerebrovascular disorders, neuropathy, kidney disease, limb amputations, and other detrimental health outcomes. Diabetes, and even pre-diabetes conditions like insulin resistance, have significant negative health impacts on both body and brain.”

When patients address their physical health needs through better self-care, Dr. Merrill says that their mental health improves, as regular exercise, a healthy diet, good sleep, and stress reduction can improve mood as much as anti-depressant medications. “These healthy lifestyle strategies are the same recommendations given to reverse insulin resistance,” he says.