Nonoperative Management of Uncomplicated Appendicitis Among Privately Insured Patients

Abstract

Importance: Health care professionals have shown significant interest in nonoperative management for uncomplicated appendicitis, but long-term population-level data are lacking.

Objective: To compare the outcomes of nonoperatively managed appendicitis against appendectomy.

Design, setting, and participants: This national retrospective cohort study used claims data from a private insurance database to compare patients admitted with uncomplicated appendicitis from January 1, 2008, through December 31, 2014, undergoing appendectomy vs nonoperative management. Coarsened exact matching was applied before multivariate analysis to reduce imbalance between groups. Data were analyzed from February 12 through May 1, 2018.

Exposures: Appendectomy (control arm) or nonoperative management (treatment arm).

Main outcomes and measures: Short-term primary clinical outcomes included emergency department visits, hospital readmission, abdominal abscess, and Clostridium difficile infections. Long-term primary clinical outcomes were small-bowel obstructions, incisional hernias, and appendiceal cancers. Nonoperative management failure was defined by hospital readmission with appendicitis diagnosis and an appendicitis-associated operation or procedure. Secondary outcomes included number of follow-up visits, length and cost of index hospitalization, and total cost of appendicitis-associated care. Covariates included age, sex, region, insurance plan type, admission year, and Charlson comorbidity index.

Results: Of 58 329 patients with uncomplicated appendicitis (52.7% men; mean [SD] age, 31.9 [16.5] years), 55 709 (95.5%) underwent appendectomy and 2620 (4.5%) underwent nonoperative management. Patients in the nonoperative management group were more likely to have appendicitis-associated readmissions (adjusted odds ratio, 2.13; 95% CI, 1.63-2.77; P < .001) and to develop an abscess (adjusted odds ratio, 1.42; 95% CI, 1.05-1.92; P = .02). Patients in the nonoperative management group required more follow-up visits in the year after index admission (unadjusted mean [SD], 1.6 [6.3] vs 0.3 [1.4] visits; adjusted +1.11 visits; P < .001) and had lower index hospitalization cost (unadjusted mean [SD], $11 502 [$9287] vs $13 551 [$10 160]; adjusted -$2117, P < .001), but total cost of appendicitis care was higher when follow-up care was considered (unadjusted, $14 934 [$31 122] vs $14 186 [$10 889]; adjusted +$785; P = .003). During a mean (SD) of 3.2 (1.7) years of follow-up, failure of nonoperative management occurred in 101 patients (3.9%); median time to recurrence was 42 days (interquartile range, 8-125 days). Among the patients who experienced treatment failure, 44 did so within 30 days.

Conclusions and relevance: According to results of this study, nonoperative management failure rates were lower than previously reported. Nonoperative management was associated with higher rates of abscess, readmission, and higher overall cost of care. These data suggest that nonoperative management may not be the preferred first-line therapy for all patients with uncomplicated appendicitis.

Figure 1.. Cohort Enrollment Criteria

NOM indicates nonoperative management.

Figure 2.. Variation in Appendicitis Treatment by Year of Diagnosis

P values represent the results of a nonparametric test for trend across ordered groups.

Figure 3.. Timing of Overall Failure of Nonoperative Management of Appendicitis by Kaplan-Meier Time-to-Event Analysis

The overall failure rate of nonoperative management (failure or recurrence leading to operative or procedural intervention) was 3.9%.