Night-shift work disturbs sleep and is associated with poor health conditions among workers. We aimed to investigate the association between night-shift work and gambling among workers and the association between night-shift work and problem gambling in working and gambling participants.

This cross-sectional study used data from an online survey conducted between February 6 and 27, 2023 in Japan. A total of 21,134 workers participated in this study, including 9,739 respondents who had gambled in the past year. We estimated the association between night-shift work and gambling among workers and the association between night-shift work and problem gambling among those who gambled at the survey. We defined problem gambling as a score ≥ 8 on the Problem Gambling Severity Index. All estimates were weighted using a nationally representative survey in Japan. We fitted multivariable weighted logistic regression models after adjusting for 14 confounders.

The weighted prevalence of gambling among non-night and night-shift workers was 42.1 % and 55.4 %, respectively. When focusing on workers gambling in the survey, the prevalence of problem gambling among non-night and night-shift workers was 8.8 % and 24.2 %, respectively. The weighted multivariable logistic regression analyses showed that night-shift work was associated with gambling participation among workers (adjusted odds ratio [aOR], 1.39, 95 % confidence interval [CI] 1.25–1.53, p < 0.001). In addition, night-shift work was associated with problem gambling among those who gambled (aOR 1.94, 95 % CI 1.57–2.40, p < 0.001).

Night-shift work was associated with gambling among workers and with problem gambling among those who gambled.