EP337 - Frailty and Hypoalbuminemia as Complementary Predictors of Outcomes in Patients >70 Undergoing Elective Colectomy for Diverticulitis: An ACS-NSQIP Analysis

Purpose/Background: Frailty reflects physiological vulnerability, while hypoalbuminemia captures nutritional and inflammatory status; two distinct but complementary domains of surgical risk. Although each factor independently predicts poor outcomes, their combined assessment may offer superior risk stratification in elderly diverticulitis patients undergoing elective colectomy for a population with higher risk for post-operative morbidity and mortality.

Methods/Interventions: We analyzed 11,617 patients >70 years undergoing elective colectomy for diverticulitis in NSQIP (2016-2023). Frailty was assessed with the modified Frailty Index-5 (mFI-5, range 0-≥4) and hypoalbuminemia classified as mild (3.0-3.5 g/dL), moderate (2.5-3.0 g/dL), or severe ( < 2.5 g/dL). The mFI-5 score was calculated based on the presence of the 5 co-morbidities: congestive heart failure within 30 days prior to surgery, insulin-dependent or noninsulin-dependent diabetes mellitus, chronic obstructive pulmonary disease or pneumonia, partially dependent or totally dependent functional health status at time of surgery, and hypertension requiring medication. Primary outcomes included 30-day mortality and readmission and secondary included reoperation and length of stay (LOS). Multivariable logistic regression identified predictors, presented as odds ratios (ORs) in forest plots.

Results/Outcomes: In our cohort (median age 75 [IQR 72-78], 73.9% female), the frailty distribution was mFI=0: 27.7%, mFI=1: 51.6%, mFI=2: 18.0%, mFI=3: 2.3%, and mFI≥4: 0.3%. Increasing frailty was associated with older age (median 76 vs 74 years, p< 0.001), higher BMI (34.2 vs 25.6 kg/m², p< 0.001), greater ASA III-IV burden (ASA IV 21.2% vs 1.6%) and preoperative sepsis (15.2% mFI≥4 vs 2.7% mFI=0). Postoperatively, length of stay increased (4 vs 13.5 days, p< 0.001), with LOS >14 days in 43.8% of mFI≥4 vs 5.3% of mFI=0. On multivariable regression, odds of mortality increased stepwise with frailty (mFI=0 OR1.03 (ns), mFI=2 OR 2.33; mFI=3 OR 3.0; mFI≥4 OR 21.93; all p< 0.05) and hypoalbuminemia (mild OR 2.75; moderate OR 4.45; severe OR 9.53; all p< 0.05). Age, postoperative septic shock, and reoperation were additional mortality predictors. For readmission, frailty remained the dominant independent predictor (mFI=2 OR 1.65; mFI=3 OR 1.98, p< 0.001). Other readmission drivers included reoperation (OR 7.19, p< 0.001), diverting loop ileostomy (OR 2.29, p< 0.001), hartmann procedure (OR 1.34, p=0.039), and hospital stay 7-14 days (OR 1.44, p=0.002).

Conclusion/Discussion: In elderly patients undergoing elective colectomy for diverticulitis, frailty and hypoalbuminemia independently predict mortality, whereas readmission is primarily frailty driven. Frailty exerts the strongest effect at higher levels, while hypoalbuminemia adds complementary risk. Joint assessment of both domains provides a practical, clinically relevant framework for perioperative decision-making, targeting frailty-focused prehabilitation, nutritional optimization, and tailored discharge planning in this vulnerable population.

Figure 1. Multivariable Logistic Regression Forest Plot Showing Adjusted Odds of Mortality and Readmission