. 2020 Feb 10;12(2):e6929. doi: 10.7759/cureus.6929

Table 2. Summary of Select Studies Evaluating Obesity Effect on Mortality in Sepsis.

BMI = body mass index; CI = confidence interval; LOS = length of stay; N/A = not applicable/not reported; NS = not significant; OR = odds ratio.

Study	No. of patients Study Design	Definitions/ Comparator	Mortality Benefit Yes/No/NS and OR	Mean Length of Stay in Hospital Increased (days)	Length of Intubation	Comments/Notes
Arabi et al¹⁷(2013)	8670 patients with septic shock Retrospective, nested cohort	Comparator: Normal weight Normal weight: 18.5-24.99 kg/m2 Obese: BMI 30-39.99 kg/m2 Very Obese: BMI >40 kg/m2	Crude: YES Obese- OR 0.80, 95% CI 0.66 to 0.97; p=0.02 Very obese- OR 0.61, 95% CI 0.44 to 0.85; p=0.003 Adjusting for baseline characteristics and sepsis interventions: NS Obese- OR 0.80, 95% CI 0.62 to 1.02; p=0.07 Very obese- OR 0.69, 95% CI 0.45 to 1.04; p=0.08	ICU LOS: NS; p=0.30 Obese- 14.7 vs. 12.5 Very obese- 14.3 vs. 12.5 Hospital LOS: YES; p=0.02 Obese- 27.8 vs. 31.8 Very obese- 34.8 vs. 31.8	N/A	There were different approaches to sepsis for obese and normal weight patients
Gaulton et al¹⁸ (2014)	1,779 patients with presumed sepsis Retrospective cohort	Comparator: Non-obese Non-obese: BMI >18.5 and <30 kg/m2 Obese: BMI >30 kg/m2	NS OR 1.11, 95 % CI 0.85-1.41, p=0.47	Hospital LOS: NS 3.1 vs. 3.83; p=0.45	N/A	ICU location at time of presumed sepsis: Obese 74.2% vs. 69.4% non-obese p=0.04
Kuperman et al¹⁹ (2013)	792 patients with sepsis Retrospective chart review	Comparator: Normal weight Underweight: BMI <18.5 Normal: BMI 18.5-24.9 kg/m2 Overweight: BMI 25.0-29.9 kg/m2 Obese: BMI 30.0-39.9 kg/m2 Morbidly obese: BMI 40.0-49.9 kg/m2	Underweight: NS OR 1.5, 95% CI 0.67-6.3 Obese: NS OR 0.72 95% CI and p value not reported Morbid obesity: NS OR 0.7, 95% CI 0.12 – 4.2; p = 0.19	NS; p=0.64 Obese: 9.0 ± 8.1 vs. 9.3 ± 8.5 Overweight: 8.8 ± 7.8 vs. 9.3 ± 8.5 Morbidly Obese: 10.2 ± 9.6 vs. 9.3 ± 8.5	N/A	BMI of 27.6 for survivors vs. 26.3 kg/m2 among non-survivors (p=0.03)
Pepper et al²³ (2019)	55,038 adults with sepsis	Comparator: Normal Weight Normal weight: BMI 18.5-24.9 kg/m2 Overweight: 25.0-29.9 kg/m2 Obese class 1: 30.0-34.9 kg/m2 Obese class II: 35.0-39.9 kg/m2 Obese class III: > 40 kg/m2	YES Adjusted odds ratio (95% CI) Underweight: 1.62 (1.50-1.74) Overweight: 0.73 (0.70-077) Obese class I: 0.61 (0.57-0.66) Obese class II: 0.61 (0.55-0.67) Obese class III: 0.65 (0.59-0.71)	Similar between groups ICU length of stay: 9 days; interquartile range, 6–15 days Hospital length of stay: 8 days; interquartile range, 6–13 days	N/A	Sepsis defined with Sepsis-3 criteria BMI calculated from data on or preceding day of sepsis diagnosis (did not include the weight change after fluid administration) Included death or hospice in mortality outcome Confounders included demographic factors, admission year, hospital-level factors, infection factors, and severity of illness
Prescott et al¹⁷ (2014)	1404 patients with severe sepsis Prospective, cohort Medicare study Followed patients for 1 year	Comparator: Normal Weight Normal weight: BMI 18.5-24.9 kg/m2 Overweight: BMI 25-29.9 kg/m2 Obese: BMI 30.0-34.9 kg/m2 Severely Obese: BMI >35 kg/m2	YES Obese: OR 0.59; 95% CI, 0.39-0.88 Severely Obese: OR 0.46; 95% CI, 0.26-0.80	Hospital LOS: NS Obese: 11.5 vs. 12.5 Severely Obese: 12.5 vs. 11.5	N/A	Total days in a healthcare facility and Medicare expenditures greater for obese (p< 0.01 for both comparisons) Average daily utilization NS (p=0.44) for overweight and obese survivors Medicare spending NS (p=0.65) for overweight and obese survivors Total function limitations following severe sepsis NS (p=0.64) Increased healthcare use concluded to be due to longer survival
Wacharasint et al 20 (2013)	778 patients with septic shock Retrospective cohort analysis	Comparator: Normal weight Normal weight: BMI <25 kg/m2 Overweight: BMI 25-29.9 kg/m2 Obese: BMI >30.0	28-day mortality: YES Overweight: BMI <25 kg/m2 vs. overweight, p=0.10 Obese: BMI <25 kg/m2 vs. obese, p=0.01 Overweight versus Obese, p=0.2	N/A	No difference in days alive and free of mechanical ventilation (obese 11, overweight 10, BMI <25 kg/m2 6 days; p=0.36	Amount of fluid per body weight significantly lower in overweight and obese patients Day 1 through Day 4; p<0.0001 Days alive and free of renal replacement therapy (obese 25, overweight 24, BMI<25 kg/m2 24 days; p=0.93) Norepinephrine: Obese 0.14, IQR 0.09-0.25 Overweight 0.21, IQR 0.12-0.34 BMI <25 kg/m2 0.26, IQR 0.15-0.44 μg/kg/minute; p< 0.0001 IL-6 significantly lower in obese and overweight compared to <25kg/m2 in early phase of septic shock; p=0.046
Wurzinger et al²¹(2010)	301 patients with septic shock Retrospective analysis on prospectively collected database	Comparator: Normal weight Normal weight: BMI 18.5-24.9 kg/m2 Overweight: BMI 25-29.9 kg/m2 Obese: BMI 30.0-39.9 kg/m2 Morbidly Obese: BMI >40 kg/m2	YES Overweight: OR 0.43; 95% CI 0.19-0.98; p=0.04 Obese: OR 0.28; 95% CI 0.08-0.93; p=0.04	ICU LOS: NS; Regression coefficient 0.03, 95% CI -0.15 to 0.21; p=0.74	NS Regression coefficient 0.05 days, 95% CI -0.1 to 0.2; p=0.49	BMI for survivors vs. nonsurvivors: 27 vs. 24; p=0.001 Elevated BMI independently associated with lower frequency of acute delirium (p=0.04) and lower need for ICU re-admission (p=0.001) Elevated BMI associated with higher rate of ICU-acquired urinary tract infections (p=0.02) Need for mechanical ventilation OR 1.02, 95% CI 0.95-1.09; p=0.66