Incorporating patient-centered quality-of-life measures for outcome assessment after Chiari malformation type I decompression in a pediatric population: a pilot study

Abstract

Objective: Optimal management of pediatric Chiari malformation type I (CM-I) is much debated, chiefly due to the lack of validated tools for outcome assessment, with very few tools incorporating patient-centered measures of health-related quality of life (HRQOL). Although posterior fossa decompression (PFD) benefits a subset of patients, prediction of its impact across patients is challenging. The primary aim of this study was to investigate the role of patient-centered HRQOL measures in the assessment and prediction of outcomes after PFD.

Methods: The authors collected HRQOL data from a cohort of 20 pediatric CM-I patients before and after PFD. The surveys included assessments of selected Patient-Reported Outcomes Measurement Information System (PROMIS) health domains and were used to generate the PROMIS preference (PROPr) score, which is a measure of HRQOL. PROMIS is a reliable standardized measure of HRQOL domains such as pain, fatigue, depression, and physical function, which are all relevant to CM-I. The authors then compared the PROPr scores with Chicago Chiari Outcome Scale (CCOS) scores derived from time-matched clinical documentation. Finally, the authors used the PROPr scores as an outcome measure to predict postsurgical HRQOL improvement at 1 year on the basis of patient demographic characteristics, comorbidities, and radiological and physical findings. The Wilcoxon signed-rank test, Mann-Whitney U-test, and Kendall's correlation were used for statistical analysis.

Results: Aggregate analysis revealed improvement of pain severity after PFD (p = 0.007) in anatomical patterns characteristic of CM-I. Most PROMIS domain scores trended toward improvement after surgery, with anxiety and pain interference reaching statistical significance (p < 0.002 and p < 0.03, respectively). PROPr scores also significantly improved after PFD (p < 0.008). Of the baseline patient characteristics, preexisting scoliosis was the most accurate negative predictor of HRQOL improvement after PFD (median -0.095 vs 0.106, p < 0.001). A correlation with modest magnitude (Kendall's tau range 0.19-0.47) was detected between the patient-centered measures and CCOS score.

Conclusions: The authors observed moderate improvement of HRQOL, when measured using a modified panel of PROMIS question banks, in this pilot cohort of pediatric CM-I patients after PFD. Further investigations are necessary to validate this tool for children with CM-I and to determine whether these scores correlate with clinical and radiographic findings.

Keywords: Chiari I malformation; health-related quality of life; outcome assessment; pediatric; posterior fossa decompression.

FIG. 1.

Flowchart representing the patient recruitment process.

FIG. 2.

Patient-reported HRQOL measures. A: Box-and-whisker plot of patient-reported average pain intensity during the month prior to assessment (n = 19 at pre-PFD assessment and n = 18 at post-PFD assessment). Median (middle line), interquartile range (box), and minimum and maximum (whiskers) are shown. Dotted lines represent the responses of individual patients traced from before to 1 year after PFD. **p = 0.007 (Wilcoxon signed-rank test). B: Body maps with color intensity representing the percent of the cohort that reported pain in the specified regions, derived by asking the patients to tap the regions of the map where they experienced pain during the month prior to assessment (n = 19 for preoperative survey and n = 20 for 1-year post-PFD survey). *p < 0.05 and **p < 0.01 (unadjusted, partially overlapping samples z-test for dichotomous variables). C: Box-and-whisker plot of pre- and post-PFD theta scores for the PROMIS domains, including functions (mobility, cognitive, and peer relationships; higher score reflects higher HRQOL) and symptoms (anxiety, fatigue, pain interference, and sleep disturbances; lower score reflects higher HRQOL). Median (middle line), interquartile range (box), and minimum and maximum (whiskers) are shown. The horizontal band at theta = 0 represents the mean of the reference population. Dotted lines represent the responses of individual patients traced from before to 1 year after PFD. •p < 0.1, *p < 0.05, and **p < 0.01 (unadjusted, Wilcoxon signed-rank test). D: Box-and-whisker plot of PROPr scores, derived from patient responses before and after PFD (n = 17 at both pre- and post-PFD assessments). A PROPr score of 1 is defined as perfect health, and a PROPr score of 0 is equivalent to death. Median (middle line), interquartile range (box), and minimum and maximum (whiskers) are shown. Dotted lines represent the responses of individual patients traced from before to 1 year after PFD. **p = 0.008 (Wilcoxon signed-rank test).

FIG. 3.

Associations between selected baseline patient characteristics and PROPr scores. Box-and-whisker plots reflecting change in PROPr scores from before to after PFD, stratified according to diagnosis of scoliosis (***p ≤ 0.001, Mann-Whitney U-test) (left) and the presence of thoracic syrinx on preoperative MRI (*p = 0.02, Mann-Whitney U-test) (right). The horizontal bar at delta PROPr = 0 represents no change in PROPr scores from before to after PFD assessment; positive delta PROPr reflects improvement of HRQOL. Median (middle line), interquartile range (box), and minimum and maximum (whiskers) are shown. Dots represent the scores of individual patients; box width is representative of the sample size.

FIG. 4.

Associations between PCS score and HRQOL outcomes. Scatterplots illustrate the direction of correlation between 1-year post-PFD PCS score and 1-year post-PFD PROPr score (left) and CCOS score (right).

FIG. 5.

Comparison of patient-centered HRQOL measures with Chiari-specific post-PFD outcome measures based on clinical impressions. A: Scatterplot of 1-year post-PFD PROPr score (left) and change in PROPr score between before and after PFD assessment (right) versus CCOS. CCOS score ranges from 4 to 16, with a higher value indicating better outcome after PFD. Raw PROPr scores range from 0 to 1, with a higher value reflecting higher HRQOL; positive delta PROPr reflects HRQOL improvement. B: Scatterplot of the pain component of CCOS versus change in patient-reported pain intensity. Higher CCOS pain component score and negative change in pain intensity reflect improvement or resolution of pain symptoms; pain intensity refers to the average pain level on a scale of 0 to 10 during the month preceding the assessment.