Associations of socioeconomic and lifestyle characteristics, psychological symptoms, multimorbidity, and multisite pain with sciatica - a 15-year longitudinal study.

ABSTRACT

BACKGROUND CONTEXT Sciatica is defined as pain radiating from the low back to the leg, usually below the knee. It is a disabling condition that causes a major burden to health care and society. Previous evidence of the multifactorial etiology of sciatica comes mostly from cross-sectional studies. Larger, longitudinal studies with a multidimensional set of variables are needed. PURPOSE: To examine how socioeconomic and lifestyle characteristics, psychological symptoms, multimorbidity, and multisite pain are associated with sciatica. STUDY DESIGN: A longitudinal study of the Northern Finland Birth Cohort 1966. PATIENT SAMPLE In total 6,683 working-aged members of the Northern Finland Birth Cohort 1966. OUTCOME MEASURES: Self-reported sciatic pain status over a 15-year study period. METHODS: We conducted a 15-year longitudinal study from the age of 31 to 46. We used multivariable generalized estimation equations analysis to examine how socioeconomic characteristics (low education, unemployment, and living alone), lifestyle characteristics (overweight, obesity, current smoking, and physical inactivity), psychological symptoms (depression, anxiety), multimorbidity, and multisite pain were associated with sciatica. RESULTS: At the age of 31, 21.1% of the study population reported sciatic pain and at the age of 46, 36.7%. Multisite pain was clearly the strongest factor associated with sciatica (odds ratio [OR] 2.61, 95% confidence interval [CI] 2.34‒2.92). In descending order of effect size, older age, low education, psychological symptoms, multimorbidity, overweight, obesity, physical inactivity and current smoking were positively associated with sciatica. Their ORs varied between 1.17 and 2.18. Living alone was negatively associated with sciatica (OR 0.81, 95% CI 0.72‒0.90). CONCLUSIONS: Multisite pain had the strongest association with sciatica. The effect sizes of the other factors were clearly smaller. To our knowledge this is the first study to evaluate the association of multisite pain with sciatica. This finding may have considerable implications for clinical work treating patients with sciatica.