Demographic and Clinical Characteristics Associated With the Failure of Nonoperative Management of Uncomplicated Appendicitis in Children: Secondary Analysis of a Nonrandomized Clinical Trial

Abstract

Importance: The factors associated with the failure of nonoperative management of appendicitis and the differences in patient-reported outcomes between successful and unsuccessful nonoperative management remain unknown.

Objectives: To investigate factors associated with the failure of nonoperative management of appendicitis and compare patient-reported outcomes between patients whose treatment succeeded and those whose treatment failed.

Design, setting, and participants: This study was a planned subgroup secondary analysis conducted in 10 children's hospitals that included 370 children aged 7 to 17 years with uncomplicated appendicitis enrolled in a prospective, nonrandomized clinical trial between May 1, 2015, and October 31, 2018, with 1-year follow-up comparing nonoperative management with antibiotics vs surgery for uncomplicated appendicitis. Statistical analysis was performed from November 1, 2019, to February 12, 2022.

Interventions: Nonoperative management with antibiotics vs surgery.

Main outcomes and measures: Failure of nonoperative management and patient-reported outcomes. The relative risk (RR) of failure based on sociodemographic and clinical characteristics was calculated. Patient-reported outcomes were compared based on the success or failure of nonoperative management.

Results: Of 370 patients (34.6% of 1068 total patients; 229 boys [61.9%]; median age, 12.3 years [IQR, 10.0-14.6 years]) enrolled in the nonoperative group, treatment failure occurred for 125 patients (33.8%) at 1 year, with 53 patients (14.3%) undergoing appendectomy during initial hospitalization and 72 patients (19.5%) experiencing delayed treatment failure after hospital discharge. Higher patient-reported pain at presentation was associated with increased risk of in-hospital treatment failure (RR, 2.1 [95% CI, 1.0-4.4]) but not delayed treatment failure (RR, 1.3 [95% CI, 0.7-2.3]) or overall treatment failure at 1 year (RR, 1.5 [95% CI, 1.0-2.2]). Pain duration greater than 24 hours was associated with decreased risk of delayed treatment failure (RR, 0.3 [95% CI, 0.1-1.0]) but not in-hospital treatment failure (RR, 1.2 [95% CI, 0.5-2.7]) or treatment failure at 1 year (RR, 0.7 [95% CI, 0.4-1.2]). There was no increased risk of treatment failure associated with age, white blood cell count, sex, race, ethnicity, primary language, insurance status, transfer status, symptoms at presentation, or imaging results. Health care satisfaction at 30 days and patient-reported, health-related quality of life at 30 days and 1 year were not different. Satisfaction with the decision was higher with successful nonoperative management at 30 days (28.0 vs 27.0; difference, 1.0 [95% CI, 0.01-2.0]) and 1 year (28.1 vs 27.0; difference, 1.1 [95% CI, 0.2-2.0]).

Conclusions and relevance: This analysis suggests that a higher pain level at presentation was associated with a higher risk of initial failure of nonoperative management and that a longer duration of pain was associated with lower risk of delayed treatment failure. Although satisfaction was high in both groups, satisfaction with the treatment decision was higher among patients with successful nonoperative management at 1 year.

Trial registration: ClinicalTrials.gov Identifier: NCT02271932.

Conflict of interest statement

Conflict of Interest Disclosures: Drs Minneci, Cooper, and Deans reported receiving funding from the Patient-Centered Outcomes Research Institute for other projects. Dr Saito reported receiving grants from the Agency for Healthcare Research and Quality outside the submitted work. Dr Mak reported receiving grants from Thrasher outside the submitted work. No other disclosures were reported.

Figures

Figure.. Study Flow of Initial Prospective, Nonrandomized, Clinical Multi-institutional Study Investigating Nonoperative Management and Surgery for Uncomplicated Appendicitis

WBC indicates white blood cell. aAlthough the nonoperative management success rate can be assessed only in the nonoperative management group, the data from all 698 patients in the surgery group were used to perform the inverse probability of treatment weighting analysis for the nonoperative management success rate. bSample sizes for secondary patient-reported outcomes vary based on availability of completed surveys for each measure. The sample size for each secondary patient-reported outcome is specified throughout the article and in Tables 1 to 4.