Pain site frequency and location in sickle cell disease: The PiSCES project

Treatment options for sickle cell disease (SCD) pain could be tailored to pain locations. But few epidemiologic descriptions of SCD pain location exist; these are based on few subjects over short time periods. We examined whether SCD pain locations vary by disease genotype, gender, age, frequency of pain, depression, pain crisis or healthcare utilization. We enrolled 308 adults with SCD in 2002-2004. Subjects kept daily pain diaries for up to 6months, including a body chart. Mixed model and generalized estimating equations were employed for analyses. Two hundred and sixty subjects completed at least one body chart. An average of 3.3/16 sites (25%) were painful. The number of pain sites varied by age, depression, frequent pain days, crisis and unplanned hospital/ED utilization. Lower back, knee/shin and hip, hurt on average more than a third of pain days, while jaw and pelvis hurt on fewer than 10% of days. Odds of a crisis were increased substantially when pain was in the arm, shoulder, upper back, sternum, clavicle, chest or pelvis (OR>1.5) while the odds of unplanned utilization were substantially increased for the sternum, clavicle and chest (OR>2.0). Pain in SCD varies considerably both within and between subjects, although it occurs most commonly in the lower back and lower extremities. The number and location of pain sites vary significantly by age, frequent pain, crisis and utilization. Identification and understanding of combinations of pain location and intensity may help to understand the etiology of SCD and improve SCD management.