Novel Risk Factors for Coronavirus Disease-Associated Mucormycosis (CAM): A Case Control Study During the Outbreak in India

Background: The epidemiology of the Coronavirus-disease associated mucormycosis (CAM) syndemic is poorly elucidated. In this study, we aimed to analyse the risk factors for CAM, in addition to those established for mucormycosis prior to COVID-19 pandemic. Methods: We performed a case-control study comparing patients diagnosed with CAM with those who had recovered from COVID-19 without developing mucormycosis. Information on comorbidities, glycaemic control, and practices related to COVID-19 prevention and management was recorded. Findings: One hundred fifty-two cases of CAM and 200 controls diagnosed with COVID-19 during April–May 2021 were included. In the CAM group, symptoms of mucormycosis began a mean 18·9 ± 9·1 days after the symptom onset of COVID-19. All, but one patient, carried either of the conventional risk factors: diabetes and steroid use. On multivariate regression analysis, risk factors associated with increased odds of CAM included presence of diabetes (aOR 3·5, 95%CI 1·1–11), poor glycaemic control (p 200 mg/dL), use of systemic steroids (aOR 7·7,95% CI 2·4–24·7), prolonged use of cloth and surgical masks (vs N95 masks, aOR 17·5, 95% CI 4·6-66·7), and repeated nasopharyngeal swab testing (aOR 1·6,95% CI 1·2–2·2). Interpretation: CAM is strongly associated with diabetes, poor glycaemic control, and systemic steroid use. Novel risk factors identified in our study include prolonged use of cloth and surgical masks vis-a-vis N95 masks, and repeated nasopharyngeal swab testing. Oxygen therapy and need for hospitalization for COVID-19 did not affect the risk of CAM. Funding Information: This was an investigator-initiated non-funded study. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: The study was approved by the Institute Ethics Committee, AIIMS, Delhi, India. [IECPG-353/28.05.21].