Low levels of plasma zinc are associated with poorer survival outcomes in patients hospitalized with COVID-19, according to new research presented at the 2020 ESCMID Conference on Coronavirus Disease.
The study involved a retrospective analysis of symptomatic COVID-19 patients admitted to a tertiary university hospital in Barcelona, Spain, between March 15 and April 30, according to Medscape. Fasting plasma zinc levels were measured at admission in patients in the COVID-19 unit and computer modelling and statistical analyses were used to assess the impact of zinc on mortality.
The average baseline zinc levels, among the 249 patients used in the study, was 61 mcg/dl. Among the 21 patients who died, baseline zinc levels were significantly lower, at 43 mcg/dl versus 63.1 mcg/dl in survivors, Medscape reports. Having a plasma zinc level lower than 50 mcg/dl at admission was associated with a 2.3 times increased risk of in-hospital death compared with the patients who had a plasma zinc level of 50 mcg/dl or higher.
Author Dr. Roberto Güerri-Fernández, who works at Hospital Del Mar in Barcelona, Spain, told Medscape: “We have submitted a paper with this work and some in vitro studies that demonstrate that zinc has some clinical implications in virus control. I believe that if these results are confirmed further studies with zinc supplementation could be done. Moreover, some studies have already been done with zinc and respiratory infections. Probably those patients with lower levels are the ones that would benefit the most.”
Jacob Teitelbaum, MD, noted in a separate statement that viral reproduction often results in “massive urinary zinc losses,” while zinc is critical for thymulin, a hormone that regulates immunity. “Therefore,” he said, “it’s not surprising that low zinc is associated with poor outcomes. Meanwhile, the low zinc is likely what is triggering the loss of taste and smell, a key symptom of zinc deficiency. In other viruses, the loss of smell usually comes from swelling in the nerve cleft for the olfactory nerve. But this is not seen as the cause in COVID-19, suggesting the zinc deficiency caused by early viral reproduction is playing a key role.”
Dr. Teitelbaum’s takeaway: “As the cost and risk of this simple nutritional support is negligible and the potential benefit is so high, I recommend that everyone I treat take 50 mg of zinc daily for one month to optimize zinc status, and then take a multivitamin with 15 mg of zinc daily to maintain optimal levels.”