With input from Dr Monica Vasudev

1314:   Metformin use is associated with reduced mortality in COVID-19 diabetics

Diabetes is an independent risk factor for COVID-19-related mortality; however, the risk is reported to be considerably reduced in patients taking metformin before the diagnosis of COVID-19. This raises the possibility that metformin may be protective in this high-risk population, suggest findings published in Frontiers in Endocrinology.

The study noted that metformin use prior to the diagnosis of COVID-19 was linked with nearly 3-fold reduction in mortality and significantly lower unadjusted and adjusted odds ratios in subjects with diabetes. The effect persisted even after correcting for age, sex, race, obesity, and hypertension or chronic kidney disease and heart failure. The mechanisms through which metformin might improve prognosis in COVID-19 go beyond any expected improvement in glycemic control or obesity as blood glucose, hemoglobin A1C, or body mass index were not lower in COVID-19 survivors on metformin.

Investigators retrospectively analyzed electronic health records of 25,326 individuals tested for COVID-19 from February 25 to June 22, 2020 at the University of Alabama at Birmingham Hospital. The primary outcome was mortality in COVID-19-positive patients. A total of 604 individuals had a confirmed positive COVID-19 test and 239 (39.6%) had diabetes. In all, 67 (11%) deaths were reported. Age of 50 and above, male sex, and hypertension were found to be associated with a significantly raised risk of death. Diabetes was associated with a “dramatic” increase in mortality and was an independent risk factor even after correcting for age, race, sex, obesity, and hypertension. Of the deaths reported, 67% occurred in patients with diabetes. 

Looking into the effects of diabetes treatment on adverse COVID-19 outcome, researchers noted that prior metformin use significantly reduced the odds of dying while prior insulin use was not found to affect mortality risk. The mortality rate of 11% among patients taking metformin was comparable to that of the general COVID-19-positive population and was considerably lower than the 24% mortality rate observed in patients with diabetes not taking metformin. Metformin treatment prior to diagnosis of COVID-19 was thus found to have an independent association with a significant reduction in mortality in patients with diabetes and COVID-19.(SOURCE: DG Alerts)

1315: High-titre plasma reduces mortality risk in non-ventilated hospitalized COVID-19 patients

Among hospitalized COVID-19 patients not receiving mechanical ventilation, transfusion of plasma with higher anti- SARS-CoV-2 immunoglobulin (Ig)G antibody levels was found to be associated with a lower risk of death compared to transfusion of plasma with lower antibody levels in a study published in The New England Journal of Medicine.

Patients who were administered plasma within 3 days after a diagnosis of COVID-19 had a lower risk of death in comparison with those who received transfusion later during the disease course.

This retrospective study included 3,082 patients hospitalized with COVID-19 from 680 acute care facilities across the US. Overall, 61% of the patients were men, and 69% were below 70 years of age. The cohort was stratified into three groups depending on anti-SARS-CoV-2 IgG antibody levels based on signal-to-cutoff ratios: low (<4.62), medium (4.62 to 18.45), or high (>18.45). Patients in the three groups were generally similar in terms of demographic characteristics, risk factors associated with severe COVID-19, and concomitant use of therapeutic agents for COVID-19. The primary outcome was death within 30 days following transfusion of convalescent plasma.

Death within 30 days after plasma transfusion was reported in 115 of 515 patients (22.3%) in the high-titre group, 549 of 2,006 patients (27.4%) in the medium-titre group, and 166 of 561 patients (29.6%) in the low-titre group. Patients in the high-titre group had a lower relative risk of death within 30 days after transfusion compared to those in the low-titre group (relative risk, 0.75; 95% confidence interval [CI], 0.61-0.93). Additional analyses with adjustment for patient demographic characteristics (age, weight status, and race) and clinical characteristics (receipt of invasive mechanical ventilation, use of concomitant therapeutics, and hypoxemia) exhibited a similar association. 

Among patients who were not receiving mechanical ventilation, death within 30 days after plasma transfusion occurred in 22.2% in the low-titre group, 19.4% in the medium-titre group, and 14.2% in the high-titre group. Among patients who were receiving mechanical ventilation, death within 30 days following plasma transfusion was reported in 43.7% in the low-titre group, 41.6% in the medium-titre group, and 40.5% in the high-titre group.

In the fully adjusted relative risk regression model, the lower risk of death within 30 days after plasma transfusion in the high-titre group was evident among patients who were not receiving mechanical ventilation before transfusion (relative risk, 0.66; 95% CI, 0.48-0.91). There appeared to be no effect on mortality among patients who received mechanical ventilation prior to transfusion (relative risk, 1.02; 95% CI, 0.78-1.32).

The unadjusted mortality within 30 days following transfusion was lower among patients who received a transfusion within 3 days after receiving a diagnosis of COVID-19 (point estimate, 22.2%; 95% CI, 19.9-24.8) compared to those who received a transfusion 4 or more days after the diagnosis of COVID-19 (point estimate, 29.5%; 95% CI, 27.6-31.6). (SOURCE: DG Alerts)

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA