Neurocognitive impairment in patients with comorbid diabetes mellitus and depression

Abstract Background Treatment of depression for individuals with type 2 diabetes improves depressive symptoms, but not glycemic control. For patients with depression and cognitive deficits, adherence to diabetes self-management goals may be especially challenging. Objective We sought to examine whether neurocognitive dysfunction is associated with impaired diabetes adherence and control, examine the effect of and determine if treatments of neurocognitive dysfunction improved glycemic control and perhaps even depression. Methods Electronic data searches of PubMed, Medline, and the Cochrane Library (years 2000–2016) were performed using keywords: depression, diabetes, cognition, and dementia. The authors, in consensus, selected pivotal studies and conducted a narrative review of twenty clinical studies. Results Depression is a risk factor for greater morbidity in individuals with type 2 diabetes. Deficits in cognition and functional capacity are also risk factors and it is likely the case that they have separable influences upon diabetes-relevant outcomes. Support of both provider management, i.e., intensification of antidepressant or hypoglycemic medication dosing, and patient medication adherence, respectively, is associated with both improved glycemic control and depressive symptoms. To date, no studies have systematically identified the cognitive deficits of individuals with diabetes and utilized neuropsychological interventions to surmount such deficits in order to achieve improved glycemic control. Conclusions Cognitive dysfunction, an important covariate in the relationship between depression and impaired diabetes self-management, can be precisely targeted. Randomized, controlled treatments of neurocognitive dysfunction in patients with diabetes should assess for improved glycemic control, and perhaps even depression.