M. Montgomery1, H. Baselice1, C. Collins1, J. Loftus1, W. Wahl1, J. Wisler1, A.D. Jalilvand1 1Ohio State University, Trauma, Critical Care, And Burns, Columbus, OH, USA
Introduction: We have previously shown that obesity is an independent predictor of mortality for septic surgical patients. It is unclear how pre-admission frailty using the modified 5-Item Frailty Index (mFI-5) modulates these data. The first objective of this study was to compare the prevalence of frailty in obese and non-obese septic surgical patients. The second goal was to define the implications of frailty on mortality for obese and non-obese surgical patients with sepsis.
Methods: We conducted a single-center retrospective review of patients admitted to the surgical ICU with sepsis (SOFA≥2, n=1401). The mFI-5 score (0-5) was calculated for each patient (hypertension requiring medication, chronic obstructive pulmonary disease, dependent functional status, congestive heart failure, and type II diabetes). Frailty (mFI-5 >2) was compared between non-obese (BMI 18.5-29.9 kg/m2, n=766) and obese patients (BMI >30 kg/m2, n=574). A multiple logistic regression was performed to determine baseline characteristics associated with a high frailty score using demographic, socioeconomic, and comorbidity data. Finally, we compared in-hospital, cumulative 90-day, and 90-day survival between obese and non-obese septic surgical patients based on frailty scores. A p <0.05 was considered significant.
Results: Using an mFI-5>2, 351 patients (25.1%) were considered severely frail. There was a higher prevalence of frailty in the obese versus non-obese cohort (30% vs 19%, p <0.001). Obesity was independently associated with a 90% increase in the odds of being frail (OR 1.92, 95th CI: 1.4-2.7), after adjusting for transfer status, socioeconomic distress, sex, age, race, and Charlson Comorbidity Index. Next, we compared in-hospital and 90-day mortality by obesity and frailty status. Within frail patients, there was no difference in in-hospital and 90-day mortality between obese and non-obese cohorts (35% vs 29%, p =0.22; 41% vs 38%, p=0.55). For non-frail patients, obesity was significantly associated with higher mortality at both time points (26% vs 15%, p <0.001; 31.5% vs 24%, p <0.001). Finally, 90-day Kaplan-Meier curves demonstrated comparable survival between the frail obese and non-obese cohorts. Within non-frail patients, obesity was associated with reduced 90-day survival compared to the non-obese patients (Figure 1).
Conclusion: Obesity is highly associated with frailty as measured by the mFI-5, underlining its implications on physiologic reserve. The impact of obesity on survival was magnified in non-frail patients, while the presence of frailty had a more dominant impact on mortality regardless of BMI. Future studies should evaluate the impact of malnutrition and clinical frailty scores in these populations