Overall reduced lymphocyte subsets worsening disease severity and prognosis in COVID 19 severe cases with diabetes mellitus in Chengdu, China

Background The outbreak of coronavirus disease 2019 (COVID-19) is widespread throughout China and the world. Methods Demographic, clinical data of 95 confirmed cases with COVID-19 on admission at the Public and Health Clinic Centre of Chengdu from January 16 to March 16, 2020, were retrospectively collected and analyzed. Of them 76, 19 cases were enrolled in non-DM group (without DM), DM group (with DM), respectively; according to the disease severity 57, 19, 8, 11 cases were further divided into non-severe non-DM subgroup (light and common type and without DM), severe non-DM subgroup (severe and critical illness type and without DM), non-severe DM subgroup (light and common type and with DM), severe DM subgroup (severe and critical illness type and with DM), respectively. The severe rate and the prognosis was compared between two groups. The data of peripheral lymphocyte and subsets, age, glucose metabolism parameters were compared between four subgroups, and its relationship to the disease severity, the viral negative conversion time, and the prognosis were analyzed.Results In this COVID-19 cohort the proportion of DM was 20%. Patients with DM had significantly higher severe rate and worse prognosis than those without DM, the difference was significant (severe rate ,cured, unhealed and death in DM and non-DM groups:61.11%vs.25.00%,26.32%,68.42%;5.26%vs.71.05%,26.32%,2.68%,х2=2.940, 3.394,P=0.003,0.001,respectively),simultaneously the proportion of DM in severe cases was higher than that in non-severe cases, the obvious difference was found (36.67% vs.12.31%,х2=2.744,P=0.006).Severe cases with DM tended to have the lowest lymphocytes count levels and percentage values, as well as the lowest T cells count levels and percentage values, helper T cells count levels and percentage values, suppressor T cells count levels, B cells count levels and percentage values compared with those severe cases without DM and non-severe cases with or without DM. The important influencing factors were that age, DM, lymphocyte percentage values and helper T cells percentage values for the disease severity, lymphocyte percentage values and B cell percentage values for the viral negative conversion time, and age, the disease severity and the viral negative conversion time for the prognosis.Conclusions The COVID-19 severe cases with DM had the lowest lymphocytes count level and percentage value, especially T and B lymphocytes count levels and percentage value. Overall decreased lymphocytes subsets and DM maybe worsen prognosis by worsening the disease severity and prolonging the viral negative conversion time. Combination immunomodulatory therapy based on comprehensive treatment might improve prognosis of the COVID-19 severe cases with DM.