Sickness Absence and Disability Pension in the Very Long Term: A Finnish Register-Based Study With 20 Years Follow-Up.

Sickness allowance is paid for short-term sickness absence and is thus an indicator of temporary ill health, but it is also associated with a heightened risk of receiving disability pension. Using event history analysis, we examined the long-term risk for disability pension receipt after first observed receipt of medically certified sickness allowance in each single year after sickness allowance was first recorded. Utilizing longitudinal data from the Finnish population register, covering the period 1989-2010, we observed 110,675 individuals aged 16-40 years at baseline. Using discrete-time hazard models, we estimated how the first observed receipt of sickness allowance was related to the risk of receiving disability pension, with an average follow-up time of 20.6 years. In this population, about 40 percent received sickness allowance and 10 percent received disability pension. In the first years after sickness allowance receipt, there was a substantial difference between long-term and short-term sickness allowance recipients in the hazard of becoming a disability pensioner. This difference levelled out over time, but even 20 years after the first observed sickness allowance receipt, the hazard of disability retirement was more than 15 times higher than that of non-recipients of sickness allowance. Patterns were similar for men and women. First observed receipt of sickness allowance is a powerful predictor for disability pension receipt, also in the very distant future. Thus, it can be used to monitor people with heightened risk of becoming more permanently ill and falling outside the labour market.