A Novel Measure of Pain Location in Adults with Sickle Cell Disease.

Background: Pain intensity remains a primary focus clinically for sickle cell disease pain assessment despite the fact that pain quality and pain location and distribution are critical for clinical diagnosis and treatment of its etiology. However, in part because of measurement issues, scant evidence is available about pain location or its relationship to intensity and quality in adults with SCD.

Aim: Our study aim was to examine sickle cell disease pain location for relationships with pain quality and intensity measured in outpatient and inpatient settings.

Methods: We used an existing longitudinal dataset prospectively collected with the valid and reliable tablet-based PAINReportIt. Adults with sickle cell disease (n = 99) reported pain location, intensity, and quality during a routine outpatient clinic visit and again during a subsequent hospitalization. From their digital body outline drawings and using the ImageJ software, we computed the pain-affected body surface area. With Pearson's correlations and paired t tests, we examined relationships between pain-affected body surface area and other pain variables across outpatient and inpatient visits.

Results: The mean pain-affected body surface area was 14.4% ± 15.0% of the total body surface area for outpatient visits (min-max: 0.0%-90.2%) and 13.5% ± 14.7% (min-max: 0.0%-73.0%) for inpatient stay. Pain-affected body surface area was positively correlated with pain quality scores for both visits but not significantly correlated with pain intensity at either visit. Compared with the outpatient visit, mean pain intensity for inpatient stay was higher (p < .001); pain quality (p = .12) and pain-affected body surface area (p = .60) did not differ significantly between visits.

Conclusions: Unknown is the explanation for pain-affected body surface area association with SCD pain quality but not pain intensity at outpatient and inpatient visits. Additional research is warranted to explore these findings and examine the clinical utility of pain-affected body surface area for chronic sickle cell disease pain and acute sickle cell disease crisis pain.