The importance of handwashing beyond COVID-19

Abstract

Background: Handwashing is recognized as effective in preventing infectious diseases. We hypothesized that handwashing may have a broader role on health. This study aimed to investigate the association between handwashing behaviours and systemic inflammation. Methods: Participants in this cross-sectional study were evaluated at 13 years old as part of the EPITeen cohort (n=1332). A global handwashing score was calculated based on the frequency of handwashing in six different situations assessed through self-completion questionnaires, with higher scores indicating poor handwashing. Serum high-sensitivity C-reactive protein (hs-CRP) was used as a measure of systemic inflammation. β coefficients (95% confidence interval) were computed using linear regression models to estimate the association between handwashing and hs-CRP concentration. Findings: Median (25th, 75th percentile) hs-CRP was 0·30 (0·10,0·80). Levels of hs-CRP significantly increased with body mass index (BMI) and male sex and decreased with parents' educational level. After adjustment for sex, BMI and parents' education, global handwashing score was positively and significantly correlated with hs-CRP levels [β 0·019, 95%CI (0·003,0·036)]. Interpretation: Low adherence to handwashing among adolescents is associated with increased systemic inflammation. These results support that handwashing behaviours may also contribute to the development of non-infectious diseases. Funding: This study was funded by the national Foundation for Science and Technology - FCT (POCI-01-0145-FEDER-016829), under the Epidemiology Research Unit - Institute of Public Health, University of Porto, grant number (UIDB/04750/2020) and under the scientific project PTDC/DTP‐EPI/6506/2014.