Hours of tolerable pain: predictors among adults with sickle cell disease

Adults with sickle cell disease experience pain that often is unpredictable in its onset and duration, but little is known about the number of hours during the 24-hour day that they experience pain greater than their tolerable level (hours of tolerable pain). We determined the predictors of hours of tolerable pain from a set of 11 demographic and pain variables reported by outpatients with SCD. 218 adult outpatients (mean age 33.7±11.3 years; 39% male; 98% African American; 73% SS, 18% SC, 9% other genotype) completed a computerized tool with items for current and past pain variables. The mean average pain intensity was 4.5±2.9, tolerable pain intensity was 3.5±2.2, and worst stomachache was 7.7±2.5. 29% of patients reported that they endured small amounts of pain before taking medication, 47% tolerated moderate pain, and 24% tolerated a large amount of pain. For 55%, their pain was tolerable for only 0-6 hours, 17% for 7-12 hours, 6% for 13-18 hours, and 23% for 19-24 hours. Using regression analysis, more time with tolerable pain was found to be associated with lower pain intensity (Est = -0.255, Z = -4.387, p<.001), higher tolerance for pain (Est=0.167, Z=2.423, p<.02), past experience with enduring moderate pain without medicine (Est=0.918, Z=2.579, p<.01), and higher level of past worst stomachache (Est=0.164, Z=2.269, p<.023). Average pain intensity appears to be a clinically significant indicator of hours of tolerable pain Helping patients with SCD to take their pain medicine with the onset of mild pain intensity may be an option for improving SCD pain control by increasing the number of hours that pain is less than the level reported tolerable by the patient.