A comparative assessment of dry eye disease among outdoor street sweepers and indoor office cleaners

Abstract

Background: Occupational predisposition to dry eye disease is known. Simultaneous exposure to multiple factors may pose more risk. Street sweepers are exposed to sunlight in addition to dust which all sweepers are exposed to. Tropical climate predisposes to significant exposure to sunlight. Combined exposure to dust and sunlight may lead to a synergy of factors. This study aims to assess the prevalence of dry eye disease (DED) amongst Street sweepers and Office cleaners in Calabar metropolis.

Methods: A cross-sectional study was conducted among street sweepers and office cleaners. A systematic random sampling and multi-stage sampling method were used to select street sweepers (n = 115) and office cleaners (n = 115) respectively for the study. A pretested semi-structured interviewer-administered questionnaire was used to obtain information after which the respondents had an ophthalmic examination. An assessment of DED was done with Ocular Surface Disease Index (OSDI) questionnaire, Schirmer's test, and tear break up time (TBUT). OSDI scores of 33 and above; Schirmer's test readings of < 10 mm wetting in 5 min and a TBUT of less than 10s in either eye were considered as positive dry eye disease. Results The majority of respondents were females 215(93.5%) compared to males 15 (6.5%). The overall mean age of respondents was 40.96 ± 9.8 years. The average OSDI score, Schirmer's test as well as TBUT among participants was 26.4 ± 16.0, 16.44 ± 9.52 mm, and 12.38 ± 4.53 s respectively. The prevalence of DED among Street sweepers was 35.7% compared to 20% among office cleaners using the OSDI questionnaire (p = 0.352). The prevalence of DED among street sweepers was 32.2% compared to 30.4% among Office cleaners using the Schirmer's test. (p = 0.73) The TBUT reported a prevalence of 38.3% of DED among Street sweepers compared to 32.2% in office cleaners. (p = 0.48) Overall; the prevalence of dry eye disease among Street sweepers and office cleaners using OSDI score, Schirmers test, as well as TBUT were not statistically significant (> 0.05) Street Sweepers had higher odds of developing dry eye disease compared to office cleaners (OR = 2.085; C.I. =1.106-3.929; p = 0.02). Negative correlation coefficient was observed between TBUT and OSDI (r_s = - 0.102; p = 0.125). This was not statistically significant.

Conclusion: Street sweepers had a higher prevalence of dry eye disease compared to office cleaners due to a higher risk of increased exposure to environmental factors such as dust, smoke, and sunlight. This effect is possibly due to a synergy of factors. Studies on dose-response are warranted.

Keywords: Dry eye disease; Ocular surface disorder, occupational health.