EMPLOYMENT STATUS, NON-DAYTIME WORK AND GASTRIC-ULCER IN MEN

Background. An excess risk of gastric ulcer (GU) (ICD-8: 531) has form erly been found in shift workers and ex-shiftworkers but little is kno wn about the risk of GU associated with other forms of non-daytime wor k. This study deals with associations between non-daytime work and GU. Methods. A fixed cohort of 122116 men in occupations in which at leas t 20% had non-daytime work and a reference group of 593281 men in occu pations with daytime work only, was followed in the National Inpatient Register for first discharges with GU as the principal diagnosis. Res ults. For men with daytime work only we found a steep inverse associat ion between GU and employment status. Men in occupational groups with late evening work had a standardized hospitalization ratio (SHR) of 23 6 (90% confidence interval [Cl]: 184-299), groups working in rosters c overing 24-hour services had an SHR of 147 (90% Cl. 116-183). A slight ly raised risk of 114 (90% CI: 101-128) was found in groups having oth er forms of non-daytime work. For all men in groups with non-daytime w ork we found a significant SHR of 130 (90% Cl. 118-142). Conclusion. W e conclude that both low employment status and non-daytime work are as sociated with an increased risk of GU.