Retinal vascular metric changes may be observed in individuals with diabetes who have a history of COVID-19, according to research published in Photodiagnosis and Photodynamic Therapy.
Researchers included 83 participants in the investigation and stratified them into 1 of 4 groups according to diabetes and COVID-19 status. The team included individuals without a history of COVID-19 or diabetes (n=21; mean age, 48.8 years), patients with diabetes and no history of COVID-19 (n=21; mean age, 54.0 years), participants with no diabetes and a history of COVID-19 (n=21; mean age, 44.6 years), and individuals with both diabetes and a history of COVID-19 (n=20; mean age, 55.4 years).
Participants underwent macular optical coherence tomography-angiography (OCT-A) scans in a 6×6 mm area. Using these scans, the team assessed retinal vascular metric changes of the superficial and deep capillary plexuses (SCP and DCP, respectively) and foveal avascular zone (FAZ) area and perimeter.
An analysis of the retinal vascular metric changes revealed that COVID-19 history affected FAZ area (P =.016), but diabetes status did not (P =.100). Individuals who had had COVID-19 demonstrated a larger FAZ area (with diabetes, 0.303 mm2; without diabetes, 0.259 mm2) compared with participants without a history of COVID-19 (with diabetes, 0.245 mm2; without diabetes, 0.217 mm2).
Both diabetes and COVID-19 status affected foveal SCP (P <.001 for both) and DCP (P =.006 and P <.001, respectively) densities. The effect size of Covid-19 (ƞ2=0.180) was greater than that of diabetes (ƞ2=0.158) for the SCP, while the effect size of diabetes (ƞ2=0.159) was greater than that of Covid-19 (ƞ2=0.091) on the DCP, according to the report.
In the cohorts without diabetes, retinal vascular metric changes among individuals who recovered from COVID-19 included significantly lower foveal SCP (mean difference [MD], -6.44%; P <.001) and DCP densities (MD, -4.65%; P =.023) compared with those who did not have COVID-19. Among participants with diabetes, COVID-19 history was associated with a significantly lower foveal SCP density (MD, -3.84%; P =.033) and increased FAZ area (MD, 0.058 mm2; P =.049).
“Although we could not establish causality, observational results showed that percentages of [vessel density were] lower in foveal SCP and DCP,” according to the study authors. “FAZ area enlarged in the diabetic patients who recovered from COVID-19. Retinal microvascular findings in these patients may be a manifestation of potential systemic vascular involvement and may be a predictor of the long-term consequences of COVID-19 in diabetic patients.”
Study limitations include a small sample size, short duration, and failure to assess retinal vascular metric changes among individuals with COVID-19 who were hospitalized.
Horozoglu F, Sener H, Evereklioglu C, Polat OA. Macular optical coherence tomography angiography analysis in diabetes mellitus patients with a history of Covid-19. Photodiagnosis Photodyn Ther. Published online March 12, 2023. doi:10.1016/j.pdpdt.2023.103513