Metformin therapy as a strategy to compensate anti-VEGF resistance in patients with diabetic macular edema.

Diabetic macular edema (DME) is the complication of diabetic retinopathy, the leading cause of vision loss among diabetic patients. Metformin is the main antidiabetic treatment. It is preferable for its great anti-angiogenic and anti-inflammatory effects. Anti-vascular endothelial growth factor (VEGF) therapy is the preferable treatment for DME despite its lack of convincing results in some patients. To assess whether the combination of metformin and anti-VEGF drugs may decrease the risk of anti-VEGF resistance among DME patients. We included DME patients with a central retinal thickness (CRT) ≥ 250 µm who consecutively underwent at least 3 anti-VEGF therapies from January 1, 2020, to December 30, 2021. Anti-VEGF resistance was defined as persistent macular edema with decreased CRT ≤ 25% after 3 anti-VEGF injections. 109 patients were considered for this research, of whom 65 (59.6%) were resistant to anti-VEGF therapy. The mean CRT of the non-metformin group decreased from 344.88 ± 129.48 to 318.29 ± 123.23 (20.85%) and from 415.64 ± 144.26 to 277.11 ± 99.25 (31.51%) (P = .031) in the metformin group. Moreover, the metformin group had fewer resistant patients than the non-metformin, 24 (45.3%) versus 41 (73.2%). Furthermore, a considerable gain in visual acuity was observed in both groups, with a BCVA gain of 40.41% in the metformin group and 39.9% in the non-metformin group. Metformin may be combined with an anti-VEGF drug to minimize the risk of anti-VEGF resistance among DME patients. Moreover, it can serve to design effective therapeutic deliveries.

Concurrent Rising of Dry Eye and Eye Strain Symptoms Among University Students During the COVID-19 Pandemic Era: A Cross-Sectional Study.

Purpose: Students spend extended hours using electronic devices due to online teaching. Digital eye strain (DES) and dry eye disease (DED) symptoms are both associated with prolonged screen exposure time and may co-occur. This study aimed to evaluate the correlation between DES and DED symptoms and determine the prevalence of DED according to the severity of DES. Patients and Methods: This cross-sectional study was conducted among international students in Chinese universities. The survey was built using Wenjuan Mini Program and distributed using the WeChat platform. The questionnaire assessed participants' screen exposure, the 20-20-20 rule, ED practices, and DED awareness. Computer Vision Syndrome Questionnaire (CVS-Q) and Dry Eye Questionnaire (DEQ-5) were used to diagnose DES and DED symptoms, respectively. Results: 498 students completed the survey, but 452 were considered for the study. Predictors of DES and DED symptoms were conjunctivitis, eye allergy, glares, tired eye, neck pain, back pain, PhD students, and daily spending > 9h on screen (P < 0.05 for all). We observed that an increase in DES scores also exponentially increases DED scores. Among students diagnosed with DES symptoms, 26.5% had mild to moderate DED symptoms, and 8.2% had severe DED symptoms. In contrast, only 8.4% and 0.9% of those with asymptomatic DES had mild to moderate and severe DED symptoms, respectively (P < 0.000). A strong and significant positive correlation (r = 0.695, P < 0.000) between DES and DED scores was found. Conclusion: We found an extremely high prevalence of DES and DED symptoms compared to the previous studies with a similar population group. We believe that the prevalence of DED may be underestimated in the young population. Training about proper ED practices is mandatory to prevent these deleterious ocular surface conditions.