This article is more than 5 years old. Information may no longer be current.
Diabetes and depression: Understanding the overlap
The connection between diabetes and depression has been clearly established, with depression found to be twice as prevalent in patients with diabetes as in the general population. The mechanism behind this comorbidity is not fully understood, and data regarding screening for and treatment of depression in diabetes is not yet adequate to address the problem. In the following three studies, from a series published in The Lancet Diabetes and Endocrinology, researchers explore the bidirectional association and possible shared origins of the two conditions, and treatments that might successfully treat these interrelated diseases.
Depression vs. diabetes distress
In one study, Frank J. Snoek, PhD, a professor specializing in psychosocial diabetology at VU University Medical Center Amsterdam, and colleagues, sought to differentiate between depression in diabetic patients and diabetes-distress, a related but distinct condition. According to the researchers, depression is a heterogeneous condition, defined by distinct symptoms of specific severity and duration. Depression in diabetes may be partly attributed to psychological distress related to living with a chronic, self-managed disease, but may not be limited to this relationship. Diabetes-distress, however, is an emotional response specific to living with diabetes, its management, and its complications. While these two psychological conditions do partly overlap, they are not synonymous, the researchers wrote. Both conditions are related to poor treatment compliance and poor glycemic outcomes, but do not appear to stem from the same underlying cause. Data-driven depression research has identified three discrete depression profiles: the metabolic-atypical profile, the chronodysregulated profile, and the melancholic anxious profile. According to the researchers, future studies should seek to better understand these profiles to establish targeted treatments.
Calum D. Moulton
Common origins?
In another study from the series, Calum D. Moulton, MRCPsych, of the department of psychological medicine, King’s College London, and colleagues, explored the growing body of evidence that type 2 diabetes and depression share common biological origins. According to the researchers, both conditions may originate from an overactivation of innate immunity, which in turn leads to a cytokine-mediated inflammatory response through impaired regulation of the hypothalamic-pituitary-adrenal axis. These pathways, according to the researchers, can lead to insulin resistance, cardiovascular disease, depression, and an increased risk of type 2 diabetes or mortality. Depression may occur in response to a direct effect of proinflammatory cytokines on the brain. The mediators of depression in type 1 diabetes are not as well researched or understood.
According to the researchers, a better understanding of the common origins of type 2 diabetes and depression could facilitate the simultaneous treatment of these conditions.
“Most excitingly, identification and modification of upstream biomarkers of both depression and type 2 diabetes could, in some cases, wholly prevent development of these two chronic and debilitating disorders,” the researchers wrote.
Optimizing treatment
According to a third study in the series by Frank Petrak, PhD, of the department of psychosomatic medicine and psychotherapy, Ruhr University Bochum, Germany, and colleagues, the current knowledge on screening and treatment for depression in diabetes is as yet insufficient. While validated instruments for the detection of depression in diabetes are readily available, these diagnostic tools are limited in their efficacy unless subsequent appropriate treatments are available. According to the researchers, this is frequently not the case. The researchers noted that because coexisting diabetes and depression have established adverse effects, treatment strategies for these patients should seek to manage the diabetes as well as glycemic control as a marker for the diabetes outcome. The researchers cited evidence showing that depression in type 1 and type 2 diabetes can be effectively treated through psychological and pharmacological approaches. In terms of improvements in glycemic control, the evidence is inconclusive: in some studies, small to moderate improvements in glycemic control have been achieved through the use of selective serotonin reuptake inhibitors or psychological treatment. – by Jennifer Byrne
References:
Snoek FJ.Lancet Diabetes Endocrinol.2015;doi:10.1016/S2213-8587(15)00135-7.
Moulton C. Lancet Diabetes Endocrinol. 2015;doi:10.1016/S2213-8587(15)00134-5.
Petrak F. Lancet Diabetes Endocrinol. 2015;doi:10.1016/S2213-8587(15)00045-5.
Disclosures: Moulton, Petrak and Snoek report no relevant financial disclosures. Please see the full studies for lists of all authors’ relevant financial disclosures.