RESUMO
OBJECTIVE: To determine whether obesity or blood pressure relate to the level of pain experienced by persons with chronic back pain. DESIGN: Retrospective Study. SETTING: University spine program. PATIENTS (OR PARTICIPANTS): Adults seeking care for back pain of more than 3 months duration. METHODS OR INTERVENTIONS (OR ASSESSMENT OF RISK FACTORS): Measurement of weight, blood pressure, and pain on a numeric scale. MAIN OUTCOME MEASUREMENTS: Relationships between body mass index (BMI) and pain, blood pressure and pain. RESULTS: 198 subjects had a mean BMI of 29.50 ± 7.12, with 33.3% obese. The relationship between pain as a continuous variable and BMI approached significance (r= 0.125, n= 175, p= 0.098). The BMI of persons with lower pain scores of 0-3 was significantly different from those with high pain scores of 7-10. No significant relationship was found between pain and systolic (r=0.126, p=0.078) or diastolic (r= 0.099, p=0.165) blood pressure. CONCLUSIONS: Contrary to assumptions about acute pain, increased chronic pain does not appear to relate to increased blood pressure. The relationship of obesity with increased pain level among persons who have chronic pain raises the possibility that psychological or physiological mechanisms may be important above and beyond the biomechanical impact of obesity.