Change in pain status in children with cerebral palsy.

AIM: To identify factors associated with a change in pain over time in children with cerebral palsy (CP).

METHOD: Pain was assessed at two time-points by physicians and caregiver-rated Health Utilities Index 3 (HUI3) pain scores.

RESULTS: One hundred and forty-eight children out of 179 approached from outpatient clinics (83% response; 104 males, 44 females mean age 8y 8mo, range 3y-16y) across all Gross Motor Function Classification System (GMFCS) levels were included. Fifty-five percent had changes in caregiver-reported HUI3 pain. A backward stepwise multiple linear regression retained HUI3 pain score at visit 1 and GMFCS level (F[2,144] =23.40, R2 =0.35; p<0.001) as variables associated with a change in pain status (HUI3 pain at visit 1: β=0.61, p<0.001; GMFCS level: β=-0.17, p<0.015). The association between HUI3 pain at visit 1 and GMFCS level was significant (β=-0.15, p<0.036). There was an association between pain etiology and pain trajectory (F[3,144] =5.39, p=0.002). Post-hoc testing revealed musculoskeletal pain had the greatest improvements compared with the no pain group (p=0.006).

INTERPRETATION: Children with CP with more severe initial pain and higher gross motor function have lower pain at follow-up indicating an improvement in pain status over time.