Risk factors of sciatic pain: a prospective study among middle-aged employees

Objective: To study the effects of occupational class, physical and psychosocial working conditions, health behaviours, and pain in the low back and the neck on sciatic pain among middle-aged employees.

Methods: The participants were municipal employees without previous sciatica, aged 40, 45, 50, 55, and 60 years at baseline (n=5261, 80% women). Sciatica was defined as low back pain radiating to the calf or the foot. Data on occupational class, physical and psychosocial working conditions, body mass index, smoking, leisure-time physical activity, neck pain, local low back pain, and sciatica were obtained from baseline questionnaire surveys in 2000-2002. The question on sciatica was repeated in a follow-up survey in 2007. Logistic regression analysis was used.

Results: In women, manual occupational class (OR 1.3; 95% CI 1.0-1.6 compared with managers/professionals), overweight (1.3; 1.1-1.5), obesity (1.4; 1.1-1.7), smoking (1.5; 1.2-1.7), low leisure-time physical activity (1.3; 1.0-1.7), previous acute (1.5; 1.3-1.7) and chronic (1.5; 1.1-2.0) local low back pain, and acute (1.20; 1.0-1.4) and chronic (1.5;1.2-1.9) neck pain predicted the onset of sciatica in a multivariable model. In men, semi-professionals (1.5; 1.1-2.1) and manual workers (2.0; 1.4-2.8) had an increased risk compared with managers/professionals; also acute (1.5; 1.2-2.0) and chronic (2.1; 1.2-3.9) local low back pain predicted sciatica.

Conclusions: Manual occupational class in both genders and semi-professional occupations in men, unhealthy behaviours and previous pain both in the neck and the lower back predicted sciatica, while physical and psychosocial working conditions had no independent effect.