Caffeine and chronic low back pain.

OBJECTIVE

Although caffeine apparently plays a role in the modulation of pain perception in a variety of acute pain states, little is known about its effects on the experience of chronic pain. This exploratory study examined the relationship between dietary caffeine consumption and the symptoms reported by patients with chronic low back pain.

DESIGN AND PATIENTS

A retrospective chart review was conducted of 131 patients with chronic low back pain (64 men and 67 women; mean age = 42.1 years; mean duration of pain = 6.1 years) referred to a multidisciplinary pain clinic over a 2-year period. Patients were classified as low (less than 100 mg; n = 34), moderate (100-400 mg; n = 68) or high (more than 400 mg; n = 29) caffeine users based on their self-reports of daily coffee, tea, and cola consumption.

RESULTS

There were no significant differences among the low, medium, and high caffeine consumer groups on any self-report measure of pain severity, affective distress, anxiety-related symptoms, or sleeping behavior. High caffeine users were more likely to be tobacco smokers than low caffeine users (79% and 27%, respectively, p < 0.001).

CONCLUSIONS

Our findings indicate that dietary caffeine consumption is not related to the global experience of pain and disability in patients with chronic low back pain, although high caffeine use may be embedded in a context of other unhealthy life-style behaviors.