Weight change and sickness absence--a prospective study among middle-aged employees.

BACKGROUND Obesity is associated with an increased risk of work disability, but studies concerning weight change are few. We examined the associations of weight change with subsequent sickness absence. METHODS Weight status data of 4164 (83% women) employees of the City of Helsinki were gathered from the Helsinki Health Study baseline survey in 2000-2002 and follow-up survey in 2007. Data were linked prospectively with the employer's sickness absence registers. Employees were categorized according to their baseline Body Mass Index (normal weight, overweight, obese) as well as weight change (weight gainer, weight loser, weight maintainer) between the two surveys. The association of weight change with sickness absence spells was analysed with Poisson regression. RESULTS Among women, those who maintained normal weight had the lowest risk for sickness absence. Weight loss, weight gain and stable obesity increased the risk for sickness absence spells of all lengths. Adjustments for covariates attenuated the association only slightly. Among men, the achieved results were mostly not statistically significant. CONCLUSIONS Preventing obesity and weight gain is important for employee well-being and work ability. Early support measures in occupational health care could benefit obese employees and those with weight gain to maintain work ability. The association between weight loss and sickness absence should be corroborated in further studies.