Chronic pain is one of several debilitating complications that arises in patients suffering from sickle cell disease with many patients reporting concurrent sleep disturbance. It is widely recognized that pain disrupts sleep, however little is known about how sleep affects pain in this population. The current analyses examined SCD patients’ calculated Insomnia Severity Index (ISI) scores and its prospective relationship to self-reported clinical pain over a 90 day electronic diary period, 3 months of weekly telephone calls, and one year of monthly telephone calls. Seventy-two African American SCD patients rated their average daily clinical pain (x=26.60/100, SD=20.84) and 64 of them remained in the study and completed the weekly and monthly calls (average clinical pain x=2.5/10, SD=1.7 and x=3.5/10, SD=1.9, respectively). Multivariate models predicting clinical pain at each time period controlled for education, sex, age, central sensitization (CS), depression, and chronic opioid therapy (COT). ISI independently predicted 7.5 % of the variance in clinical pain during the diary period. The overall model accounted for 76% of the total variance, with COT, CS, and ISI significant covariates in the model. ISI independently predicted 7.6% of the variance in clinical pain over the 3 months of weekly calls. Both COT and ISI were significant in this model, for which 65% of the total variance was accounted. Lastly, in the twelve month period of monthly calls, ISI independently predicted 9.2% of the variance in clinical pain during the final 12 months of observation, accounting for 66% of the variance. COT, ISI, and depression were significant for this final model. These data suggest that sleep has a significant and long-lasting influence on SCD pain and deserves further, in-depth investigation.
© 2017 Published by Elsevier Inc.