ASSESSEMENT OF OUTCOMES FOLLOWING IMPLEMENTATION OF ANTIVIRAL TREATMENT GUIDELINES FOR COVID-19 DURING THE FIRST WAVE IN THAILAND

Thailand encountered its first coronavirus disease 2019 (COVID-19) outbreak in March 2020 and the Thailand Ministry of Public Health rapidly developed COVID-19 treatment guidelines. In this study we aimed to describe the outcomes among patients treated following those initial guidelines and determine factors significantly associated with poor outcomes in order to inform efforts to improve COVID-19 treatment guidelines for Thailand. Nine hospitals in Bangkok submitted data from their COVID-19 patients using standardized case record forms. A poor outcome was defined as death, ICU admission, requiring intubation or requiring high-flow oxygen. Factors associated with these outcomes were assessed. A total of 744 patients (48.8% male) were included in the study. The median (interquartile range) age of study subjects was 37 (27-48) years; 8.4% were aged >60 years, 5.6% of subjects were obese and 16.5% had underlying conditions: obesity, immunocompromised status, diabetes, chronic conditions of lungs, kidneys, liver, cardiovascular or cerebrovascular systems or had an absolute lymphocyte count <1,000 cells/mm 3 . Among symptomatic patients, factors significantly independently associated with a poor outcome were: age >60 years (adjusted odds ratio (aOR): 2.50, 95% confidence interval (CI): 1.17-5.36, p = 0.018), having an underlying risk condition (aOR: 2.36, 95%CI: 1.27-4.39, p = 0.007), presenting with pneumonia (aOR: 6.60, 95%CI: 3.48-12.49, p <0.001) and azithromycin use (aOR: 2.36, 95%CI: 1.30-4.31, p = 0.005). Among symptomatic patients, the factor significantly associated with lower odds of having a poor outcome was hospital admission within 4 days of symptom onset (aOR: 0.44, 95%CI: 0.24-0.82, p = 0.009). Subgroup analysis revealed hospital admission within 4 days of symptom onset was significantly associated with a lower risk of a poor outcome only among patients who received treatment that included favipiravir (crude odds ratio (cOR): 0.320, 95%CI: 0.152-0.662, p = 0.003), but not among those who received a ritonavir boosted protease inhibitor (lopinavir or darunavir) or hydroxychloroquine (or chloroquine) without favipiravir (cOR: 0.58, 95%CI: 0.18-1.91, p = 0.372). In summary, the factors significantly associated with greater odds of having a poorer outcome were: age >60 years, having an underlying risk condition, presenting with pneumonia and azithromycin use; and with lower odds of having a poor outcome was being treated with favipiravir within 4 days of symptom onset. Thai guidelines have been updated to include early initiation of favipiravir, particularly among those with underlying risk conditions. Further studies are needed to determine if implementation of guidelines taking into account of all these factors will result in improved outcomes.