Prevalence of sick building syndrome and its association with perceived indoor environmental quality in an Asian multi-ethnic working population

Abstract

BackgroundSick building syndrome (SBS) is a condition affecting occupants of a building from which they may experience a series of non-specific symptoms from being in that building. We aimed to (1) estimate the prevalence of SBS (2), assess the association between perceived indoor environmental quality (IEQ) in aboveground and underground workspaces, and to what extent workspace location modifies these associations. MethodsA total of 329 workers in aboveground and underground workspaces were followed-up in three assessments for 12 months in Singapore. Data on socio-demographic characteristics, lifestyle/health-related factors, and workplace factors were collected through self-administered questionnaires. Perceived IEQ satisfaction score of air, temperature, noise, and light were collected using the OFFICAIR questionnaire. We used generalised estimating equation models to assess the association between perceived IEQ and SBS, adjusting for potential confounders. SBS was defined as having two or more symptoms at least twice per week. ResultsThe prevalence of SBS declined significantly from 17.9% to 8.5% over the assessments. The odds ratio for SBS associated with 1-unit increase in perceived air quality score was 0.93 (95% CI: 0.89–0.97) in both workspaces combined and 0.91 (0.86–0.97) in aboveground workspaces. The odd ratio associated with 1-unit increase in perceived temperature comfort score was 0.94 (0.89–1.00) in both workspaces combined and 0.87 (0.78–0.96) in underground workspaces. No modification effect of workspace location was observed. ConclusionPerceived indoor environmental quality can provide a useful tool for environmental health impact assessments. Our findings have potential implications for the development of healthy building policies.