CST3 and COVID-19: Among baseline comorbidities, general long standing illness (RR 1.59), baseline diabetes (RR 2.16), baseline CVD (RR 1.93), sleep apnoea (RR 3.32), statin use (RR 1.80), higher inflammatory markers (particularly white blood cell count; RR 1.17 per SD increase) and higher cystatin C (RR 1.34 per SD increase) were also associated with confirmed COVID-19 (table 1).