Study explores mental health issues in patients with diabetic retinopathy

August 1, 2020

Rates of anxiety and depression increased but were not necessarily tied to disease severity

This article was reviewed by Daniel Olson, MD, and Alice Yang Zhang, MD.

It is reasonable to expect that the burdens associated with having diabetes and diabetic eye disease could affect mental health. A study conducted by researchers at the University of North Carolina investigating associations between anxiety, depression, and diabetic retinopathy (DR) provides evidence supporting this hypothesis.

The research was led by Alice Yang Zhang, MD, Assistant Professor of Ophthalmology, University of North Carolina, Chapel Hill, and reported by Daniel Olson, MD, ophthalmology resident, at ARVO 2020.

The results showed that patients with DR were at increased risk of having psychiatric comorbidities compared with the general population. Further analyses stratifying patients by DR severity, however, did not identify consistent correlations between the risk of the psychiatric comorbidities and stage of DR.

“The chronicity of diabetes, adherence to lifestyle changes that are recommended for controlling blood glucose and blood pressure to prevent diabetes-related complications, and the prospects of potential vision loss and interventions to treat diabetic eye disease can take a psychological toll on patients,” Olson said. “The findings from our study are consistent with that idea and support the importance of interdisciplinary coordination in patient care as ophthalmologists and primary care providers work together to manage diabetes, DR, and mental illness comorbidities in our patients.”

Subjects included in the retrospective cohort study were identified using the Carolina Data Warehouse, which is a statewide, de-identified repository for all patients seen through the University of North Carolina Health Care System. The database was searched to identify individuals aged ≥18 years who had a documented eye exam between July 2008 and July 2018. Diagnoses of DR, anxiety, and depression were determined based on ICD-9/ICD-10 codes.
Odds ratios for having anxiety, depression, and both comorbidities were calculated using multiple regression models controlling for age and sex and also stratifying patients with DR into four severity subgroups: mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR, and proliferative DR (PDR).

A total of 95,575 subjects were included in the study, of which 4,315 (4.5%) had DR, 18.8% had anxiety, and 21% had depression. Comparisons of groups with and without DR showed that the prevalence of both anxiety and depression were higher in the subjects with DR, although only the difference in the rate of depression was statistically significant, Olson noted.

“The prevalence rates of anxiety and depression in our overall population and in the group without DR were consistent with rates that are reported in the literature for the general population,” he said.

The multiple regression analyses showed that the patients with DR had a significantly increased risk of having anxiety, depression, and both diagnoses. In the analyses of severity subgroups, the risk of having depression was increased regardless of DR severity, but was lowest in the group with PDR. The risk of having both anxiety and depression was increased in all DR subgroups except those with moderate NPDR, but only patients with mild NPDR had an increased risk of having anxiety.

Olson proposed two explanations for the finding that the risk of having comorbid depression was lowest in the PDR subgroup.

“One possibility considers that diabetes is often a slowly progressing disease. Over time, patients may become depressed as they begin to lose vision from their DR and anticipate the need for treatment. Once they reach the PDR stage, however, they may have become resigned to their disease or discover that the necessary treatments are not as onerous as they originally thought,” he said.

“Alternatively, patients with PDR may be less likely to be diagnosed with depression based on the idea that they are less active participants in their healthcare and not following up with their primary care physician who would be more likely than the ophthalmologist to be administering mental health screening questionnaires,” he added.

Other sub-analyses investigated demographic-related influences on rates of depression and anxiety in patients with DR. The results showed that patients aged <65 years were significantly more likely than their older counterparts to have comorbid anxiety.

In addition, the odds of having comorbid depression were consistently increased among men while most groups of women also had increased risk of having a concurrent diagnosis of depression, with the exception of women with severe NPDR, where no significant relationship exists.

“Further studies are merited to better understand these findings pertaining to age and sex,” Olson said.

Daniel Olson, MD
E: daniel.olson@unchealth.unc.edu
Alice Yang Zhang, MD
E: alice_zhang@med.unc.edu
None of the investigators has any relevant financial interests to disclose.