The association between carotid intima-media thickness and sciatica

Both clinical and epidemiologic studies have shown an association between atherosclerotic changes in the aorta or lumbar arteries and lumbar disc degeneration. However, the association between atherosclerosis and sciatica remains unknown. The aim of this study was to investigate the association between carotid intima-media thickness and sciatica.

The target population consisted of people aged 45 to 74 years, who had participated in a Finnish nationwide population study during the period 2000 to 2001 and lived within 200 km of the 6 study clinics. Of the 1867 eligible subjects, 1386 (74%) were included in the study. We used high-resolution B-mode ultrasound imaging to measure intima-media thickness, and local or radiating low back pain was determined by a standard interview and clinical signs of sciatica through a physician's clinical examination.

Carotid intima-media thickness was associated with continuous radiating low back pain and with a positive unilateral clinical sign of sciatica among men only. After adjustment for potential confounders, each standard deviation (0.23 mm) increment in carotid intima-media thickness showed an odds ratio of 1.6 (95% confidence interval 1.1-2.3) for continuous radiating low back pain and 1.7 (95% confidence interval 1.3-2.1) for a positive unilateral clinical sign of sciatica. Carotid intima-media thickness was not associated with local low back pain.

Sciatica may be a manifestation of atherosclerosis, or both conditions may share common risk factors.