Accelerated progression of diabetic retinopathy following severe COVID-19 infection.

Purpose: The impact of SARS-CoV-2 infection on pre-existing retinal pathology is currently unknown. Observations: We present a unique case of rapidly progressing diabetic retinopathy (DR) following severe COVID-19 infection requiring supplemental oxygen and subsequent long-COVID. Conclusions and importance: Following infection with SARS-CoV-2, the associated acute and possible long-term hypoxia has the potential to affect the retina and accelerate the natural course of diabetic retinopathy.

The Relationship of Current Cognitive Activity to Brain Amyloid Burden and Glucose Metabolism.

Several studies have investigated how lifetime cognitive engagement affects levels of amyloid-beta (Aß) deposition in the brain. However, there has been some disagreement, leaving the relationship of cognitive activity (CA) to Aß a largely open question. The present study investigated the relationship between CA, Aß deposition, and glucose metabolism. One hundred nine cognitively normal participants underwent Pittsburgh Compound-B (PiB) and [18F]fluorodeoxyglucose-positron emission tomography and completed a questionnaire designed to measure current CA. Statistical analyses revealed significant differences in PiB retention between those in the high and low CA groups. Linear regression models revealed a significant negative relationship between PiB retention and CA and a significant positive relationship between glucose metabolism and CA. These data suggest that CA may have a direct beneficial effect on the pathophysiology of AD or reflect another underlying process that results in both higher CA and lower AD pathophysiology.