Deconstructing 30-day readmission after bariatric surgery into severity-graded phenotypes: a national analysis

Area of Science:

• Metabolic and bariatric surgery outcomes
• Surgical quality metrics
• Patient safety in bariatric procedures

Background:

• Thirty-day readmission is a standard bariatric quality metric.
• Current metrics do not differentiate readmission severity, equating minor issues with major complications.

Purpose of the Study:

• To classify 30-day bariatric readmissions by severity.
• To assess if conversion operations increase the risk of higher-acuity readmissions.

Main Methods:

• Analysis of 949,507 bariatric operations from 2020-2024 using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database.
• Readmissions graded hierarchically (Grade A: minor, Grade B: reintervention, Grade C: major complications).
• Multinomial logistic regression and inverse probability of treatment weighting used to compare conversion vs. primary operations.

Main Results:

• 3.3% of operations (30,978) had 30-day readmissions, with conversion surgery having double the rate (6.1% vs. 2.9%).
• Readmissions after conversion were shifted towards higher acuity (Grades B and C).
• Reverse conversions showed a sevenfold increased risk of Grade C readmissions, with leak rates near 5%.

Conclusions:

• Conversion operations are linked to higher readmission frequency and severity.
• Reverse conversion procedures require specific consent discussions due to high complication rates.
• A severity-aware readmission metric is proposed to more accurately reflect bariatric surgery quality.