Sanjoy Paul, PhD: Depression, Antidepressant Use Among Diabetes Patients

A recent study of more than 1.7 million type 2 diabetes (t2d) patients from the US and UK has found a high prevalence rate of depression and antidepressant use in incident t2d, regardless of a clinical diagnosis of a mental illness.

Investigators presented the findings of their study at the American Diabetes Association (ADA) 2019 Scientific Sessions in San Francisco, CA.

Using Centricity Electronic Medical Records to identify 1,395,572 million patients from the US and The Health Improvement Network database to identify 343,714 from the UK to include in the study. Investigators analyzed records to evaluate trends and risk of developing depression in young t2d patients in real world settings from 2010 to 2016.

Upon analyses, investigators found that at the time of t2d diagnosis that 2% of US patients had depression but were not using antidepressants, 16% were on antidepressants without a diagnosis of depression, and 9% were using antidepressants with a diagnosis of depression. Conversely, 8% of the UK cohort had depression but were not using antidepressants, 10% were using antidepressants without a diagnosis of depression, and 15% were using antidepressants with a diagnosis of depression.

Investigators noted that, over the study period, the prevalence of depression, mental illness and antidepressant use in the UK increased — while prevalence of antidepressant use and mental illness increased in the US. From 2010 to 2016, use of antidepressants without a diagnosis of depression or mental illness increased from 16% to 26% in the US cohort and from 5% to 41% in the UK cohort.

Rates of depression and antidepressant use were significantly higher in the US cohort. Additionally, in patients with a co-morbid condition at time of t2d diagnosis, those 50 years or younger had higher risks of developing depression compared to those 60 and older. Those increases were 28% in the US cohort and 18% in the UK.

Study author Sanjoy Paul, PhD, professor at University of Melbourne, sat down with MD Magazine® at ADA 2019 to discuss the impact of those findings and what it means for doctors treating patients with t2d.

MD Mag: What did you find when examining prevalence and incidence rates of depression among patients with type 2 diabetes?

Paul: Both diabetes and mental illness is a big global burden and we also know that the prevalence of mental health issues including depression is pretty high in patients with diabetes, however no study to date has evaluated the temporal changes in the pattern of prevalence and incidence of depression and use of antidepressants in any mental illness at the time of diagnosis of diabetes. So, it's in newly diagnosed type 2 diabetes people. So, what we have done is using nationally representative patient level electronic medical records from USA, which is the current date is about 4 to 6 million patients, and the primary care electronic medical records arguably the world's largest EMR from primary care system in United Kingdom we have evaluated the prevalence and the temporal changes in the prevalence of clinical diagnosis of depression, any mental illness, and also the prevalence of the use of antidepressants with or without clinical diagnosis of depression at the time of diagnosis of diabetes from 2000 till 2016.

What we have observed is that, especially United Kingdom, starting from around 15% prevalence of clinical diagnosis of depression and use of antidepressants irrespective of having or not having a clinical diagnosis of depression there is an exponential rise in the prevalence from 15% to up to about 35% and this is really striking over the last decade. In the proportion of people who are taking antidepressants of any kind is indeed exponentially increasing without the clinical diagnosis of any dire depression exponentially — for both countries UK as well as USA.

This is striking what we have also observed that the prevalence of depression as well as the incidence rate of depression in patients with new diagnosis of diabetes is 1.5 to 2 times higher in women compared to men and if you look at the whole spectrum of the last decade the incidence of depression irrespective of whether you're having a clinical diagnosis of depression or using antidepressants without a clinical diagnosis of depression the risk is significantly high from 24 to 45% over the whole spectrum of the last decade in younger people especially those who are below the age of 50 compared to the older people.

Indeed, the use of antidepressants has exponentially increased in both countries among people who are young within the age of 30 or 40 from 18 at the time of diagnosis of diabetes and it is also true at the same time that the incidence of young onset diabetes is also significantly increasing over the period of time. So, this is very striking and what this clinically — and also at the public health level — it means is that we need to have a proactive, very focused policy of evaluating mental health issues in people with metabolic diseases especially in people with diabetes and cardiovascular diseases.