Association between underlying health conditions and long COVID among non-hospitalized and hospitalized individuals as modified by health literacy: A multi-center study

We investigated the effect modification of health literacy (HL) in ameliorating the negative impact of underlying health conditions (UHC) on long COVID among non-hospitalized and hospitalized survivors. An online cross-sectional study was conducted in Vietnam from December 2021 to October 2022. A sample of 4,507 participants recruited from 18 hospitals and health centers were those aged 18 or older, had contracted COVID-19 for at least 28 days, and were not in the acute phase of reinfection. Participants reported their long COVID symptoms, UHC, health literacy, socio-demographics, clinical parameters, the COVID-19 impact battery disability scale, and health-related behaviors. The logistic regression models were used to examine the associations and interactions. Underlying health conditions were associated with a higher likelihood of long COVID in non-hospitalized participants (adjusted odds ratio, aOR= 2.10 [1.61, 2.61]; p