Table 3.
Differences in potential confounders among BMI categories
| Variable | Underweight (n = 88) | Normal (n = 544) | Overweight (n = 399) | Obese (n = 326) | Severely Obese (n = 131) | p Valuea |
|---|---|---|---|---|---|---|
| SAPS II probability of survival | 0.53 (0.29) | 0.58 (0.28) | 0.59 (0.29) | 0.59 (0.28) | 0.68 (0.29) | <.001 |
| Age, yrs | 62.4 (16.2) | 61.0 (17.8) | 59.4 (16.7) | 58.0 (16.3) | 53.6 (14.9) | <.001 |
| Male | 41 (46.6%) | 307 (56.4%) | 223 (55.9%) | 152 (46.6%) | 44 (33.6%) | <.001 |
| Diabetes diagnosis | 10 (11.4%) | 87 (16.0%) | 98 (24.6%) | 113 (34.7%) | 52 (39.7%) | <.001 |
| Hypertension diagnosis | 23 (26.1%) | 207 (38.0%) | 172 (43.1%) | 166 (50.9%) | 66 (50.4%) | <.001 |
| Pulmonary disease diagnosis | 38 (43.2%) | 215 (39.5%) | 129 (32.3%) | 109 (33.4%) | 60 (45.8%) | .012 |
| Cancer diagnosis | 14 (15.9%) | 110 (20.2%) | 67 (16.8%) | 49 (15.0%) | 14 (10.7%) | .071 |
| Cardiovascular disease diagnosis | 42 (47.7%) | 325 (59.7%) | 239 (59.9%) | 209 (64.1%) | 83 (63.4%) | .078 |
BMI, body mass index; SAPS, Simplified Acute Physiology Score.
a
Kruskal-Wallis test for continuous variables; Pearson’s chi-square test for categorical variables. Body mass categories are defined as follows: Underweight BMI, <18.5 kg/m2; Normal BMI, 18.5–24.9 kg/m2; Overweight BMI, 25–29.9 kg/m2; Obese BMI, 30–39.9 kg/m2; Severely Obese BMI, ≥40 kg/m2. Continuous variables are presented as mean (SD). Categorical variables are presented as frequency (%).