Much of what I have learned about living with and recovering from a mental disorder I discovered on my own. I remain grateful, however, to the physician at the district health facility who spoke with me a decade ago about mental illness as a predictor of Type 2 diabetes mellitus (T2DM).
I discovered back then that for a while research had been ongoing on the link between psychiatric illnesses and the incidence of diabetes, and the correlation of the former with a higher prevalence of T2DM.
A diagnosis of T2DM means that the body is not using insulin properly and this type is the most common form of diabetes.
Researchers have long found bidirectional associations where people living with depression are more likely to develop T2DM, and people with diabetes are more likely to develop depression than those who live without either of those conditions.
The present and future global danger of these as comorbid illnesses, however, lies in the high prevalence of both mental illnesses and T2DM as individual conditions.
The World Health Organization (WHO, 2021) says that one billion people (one in eight) globally live with a mental disorder. The International Diabetes Federation (IDF, 2022), reports that worldwide 537 million (one in ten) adults aged 20-79 were living with diabetes in 2021, with an expected rise to 643 million and 783 million in 2030 and 2045, respectively.
By themselves, both psychiatric illnesses and T2DM are responsible for high morbidity and mortality; both contribute to premature deaths. Severe mental illnesses are known to shorten people’s life by about 17 years as compared to the general population.
Diabetes, the fifth most common cause of death in the world, accounted for 6.7 million deaths in 2021 (IDF). And, life expectancy, according to UK researchers (2010) is reduced on average by up to ten years in people with T2DM. They estimated in people with Type 1 diabetes life could be shortened by more than 20 years.
Researchers worldwide also agree that myocardial infarction (heart attack) is the most common cause of death in diabetic patients. Without proper intervention, a diabetic patient can develop physical health issues such as cardiovascular disease, cerebrovascular disease (strokes), hypertension, neuropathy (nerve damage), and retinopathy (eye nerve damage) which can lead to blindness and other conditions which impair health and shorten life expectancy. Being diagnosed and managing any of these also impacts a person’s mental health.
Studies have been done to show that T2DM is more consequential among people with serious mental illnesses than in those without these conditions, and as well, to show how death in those living with these conditions as comorbid occurrences are higher than when they are not combined.
A 2022 Time Magazine article titled, The Link Between Type 2 Diabetes and Psychiatric Disorders, quotes Anne Doherty, a University College Dublin associate professor of psychiatry saying, “When people who have pre-existing mental illnesses develop diabetes, their outcomes are much worse. Compared to people with Type 2 diabetes who don’t have mental illnesses, they are more likely to develop complications, and they’re significantly more likely to die younger.
“The relationship goes both ways; people with diabetes also tend to have higher rates of psychiatric disorders and face worse outcomes than people without diabetes.”
What explains the nexus to some extent is that both mental disorders and diabetes have overlapping risk factors, especially those of diet and exercise.
A person living with a mental illness can be faced with symptoms of fatigue, low energy, social withdrawal, and a general lack of desire for physical activity. They may not be motivated to eat properly and may experience weight gain (from other factors related to the mental disorder, too). Binge or disordered eating, which further exacerbate the diabetic condition, may also be a factor.
Inactivity, poor nutrition, and weight gain are among the highest risk factors for developing T2DM.
Seena Fazel, an Oxford University forensic psychiatry professor who was also quoted in Time Magazine says, “Depression can make it harder to exercise, eat healthy, or adhere to a medication regimen, all of which can increase diabetes risk.”
Fazel said a person with a mental disorder often may “self-medicate with alcohol and drugs”, and that sleep disruption, which is common with psychiatric illnesses, presents as a risk factor.
When diagnosed with T2DM, an individual may be emotionally affected and may struggle with issues of denial, fear, anger, irritation and other emotions that can prompt depression, anxiety, and stress.
Added to the dilemma is the fact that often patients with chronic health conditions such as T2DM do not receive care, interventions or counselling about their mental health. Very often clinical interventions may ignore the fact that an integrated approach to treatment of multiple illnesses is necessary to promote patients’ overall well-being.
Risk factors
What explains the nexus to some extent is that both mental disorders and diabetes have overlapping risk factors, especially those of diet and exercise.
A person living with a mental illness can be faced with symptoms of fatigue, low energy, social withdrawal, and a general lack of desire for physical activity. They may not be motivated to eat properly and may experience weight gain (from other factors related to the mental disorder, too). Binge or disordered eating, which further exacerbate the diabetic condition, may also be a factor.
Inactivity, poor nutrition, and weight gain are among the highest risk factors for developing T2DM.
Seena Fazel, an Oxford University forensic psychiatry professor who was also quoted in Time Magazine says, “Depression can make it harder to exercise, eat healthy, or adhere to a medication regimen, all of which can increase diabetes risk.”
Fazel said a person with a mental disorder often may “self-medicate with alcohol and drugs”, and that sleep disruption, which is common with psychiatric illnesses, presents as a risk factor.
When diagnosed with T2DM, an individual may be emotionally affected and may struggle with issues of denial, fear, anger, irritation and other emotions that can prompt depression, anxiety, and stress.
Added to the dilemma is the fact that often patients with chronic health conditions such as T2DM do not receive care, interventions or counselling about their mental health. Very often clinical interventions may ignore the fact that an integrated approach to treatment of multiple illnesses is necessary to promote patients’ overall well-being.
