Objective: To study whether having ever had local low back pain (LBP), sciatica, neck pain (NP), or some combination of LBP and NP, predicts sickness absence among municipal employees.
Methods: The study sample (n=6911, 80% women, response rate 67%) included employees of the City of Helsinki who reached the age of 40, 45, 50, 55, or 60 years between 2000-02. Survey data on pain, working conditions, and health behaviours were linked to register data on sickness absence for three subsequent years. Sickness absence was categorised as self-certified (lasting for 1-3 days) and medically certified (lasting for 4 days or more) and the number of spells during the follow up was analysed using Poisson regression analysis.
Results: In women, medically certified sickness absence was predicted by sciatica (rate ratio, RR, 1.3, 95% CI 1.1-1.6), NP (RR 1.3, 95% CI 1.2-1.5) and the combination of sciatica and NP (RR 1.8, 95% CI 1.6-2.1), allowing for working conditions, body mass index, and smoking. In men, the corresponding RRs were 1.5 (95% CI 1.0-2.1), 1.7 (95% CI 1.2-2.4), and 2.2 (95% CI 1.6-2.9). Local LBP did not predict medically certified sickness absence. Self-certified sickness absence was modestly predicted by all pain categories in women (RRs between 1.2 and 1.5) and by NP alone and with local LBP or sciatica in men (RRs between 1.4 and 1.6).
Conclusions: Medically certified sickness absence was predicted by sciatica and NP, but not by local LBP. The association was accentuated in those with both sciatica and NP. Pain combinations may have a stronger effect on work ability than pain in one location.