Ann Clin Microbiol 2026;29(3):13. Risk factors for severe Clostridioides difficile infection in Korea: a retrospective cohort study
| Variable | Non-severe CDI (Control, n = 423) | Severe CDI (Case, n = 485) | Unadjusted OR (95% CI) | P-value |
|---|---|---|---|---|
| Demographics and setting | ||||
| Age (yr), median (IQR) | 78.0 (68.0–83.0) | 77.0 (68.0–83.0) | 1.00 (0.99–1.01)a) | 0.994 |
| Age (yr), mean (SD) | 73.6 (14.6) | 74.1 (13.7) | — | 0.629 |
| Male sex, n (%) | 181 (42.8) | 260 (53.6) | 1.54 (1.19–2.01) | 0.001 |
| Healthcare-associated acquisition, n (%) | 293 (69.3) | 367 (75.7) | 1.38 (1.03–1.85) | 0.037 |
| Clinical history and prior exposures | ||||
| History of prior recurrent CDI, n (%) | 7 (1.7) | 20 (4.1) | 2.56 (1.07–6.11) | 0.047 |
| Proton pump inhibitor use, n (%) | 119 (28.1) | 117 (24.1) | 0.81 (0.60–1.09) | 0.194 |
| Prior antibiotic exposure (any, within 12 weeks), n (%) | 280 (66.2) | 387 (79.8) | 2.02 (1.49–2.72) | < 0.001 |
| Narrow-spectrum cephalosporin, n (%) | 21 (5.0) | 44 (9.1) | 1.91 (1.12–3.27) | 0.023 |
| Extended-spectrum cephalosporin, n (%) | 141 (33.3) | 186 (38.4) | 1.24 (0.95–1.63) | 0.133 |
| β-lactamase inhibitor combination, n (%) | 119 (28.1) | 220 (45.4) | 2.12 (1.61–2.80) | < 0.001 |
| Carbapenem, n (%) | 54 (12.8) | 81 (16.7) | 1.37 (0.94–1.99) | 0.117 |
| Fluoroquinolone, n (%) | 80 (18.9) | 126 (26.0) | 1.50 (1.10–2.07) | 0.014 |
| Teicoplanin, n (%) | 22 (5.2) | 64 (13.2) | 2.77 (1.68–4.58) | < 0.001 |
| Penicillin, n (%) | 5 (1.2) | 3 (0.6) | 0.52 (0.12–2.19) | 0.582 |
| Underlying comorbidities | ||||
| Charlson comorbidity index, median (IQR) | 1.0 (0.0–3.0) | 2.0 (0.0–3.0) | 1.08 (1.01–1.16)a) | 0.003 |
| Pneumonia, n (%) | 82 (19.4) | 148 (30.5) | 1.83 (1.34–2.49) | < 0.001 |
| Chronic renal disease, n (%) | 71 (16.8) | 117 (24.1) | 1.58 (1.13–2.19) | 0.008 |
| Cerebrovascular disease, n (%) | 45 (10.6) | 77 (15.9) | 1.59 (1.07–2.35) | 0.027 |
| Nutritional deficiency, n (%) | 19 (4.5) | 36 (7.4) | 1.70 (0.96–3.02) | 0.088 |
| Heart failure, n (%) | 16 (3.8) | 31 (6.4) | 1.74 (0.94–3.22) | 0.105 |
| Diabetes mellitus, n (%) | 111 (26.2) | 133 (27.4) | 1.06 (0.79–1.43) | 0.745 |
| Malignancy, n (%) | 61 (14.4) | 72 (14.8) | 1.03 (0.72–1.50) | 0.931 |
| Chronic respiratory disease, n (%) | 18 (4.3) | 17 (3.5) | 0.82 (0.42–1.61) | 0.680 |
| Atherosclerosis, n (%) | 13 (3.1) | 21 (4.3) | 1.43 (0.71–2.89) | 0.412 |
| Biliary tract disease, n (%) | 9 (2.1) | 17 (3.5) | 1.67 (0.74–3.79) | 0.297 |
| Liver cirrhosis, n (%) | 10 (2.4) | 10 (2.1) | 0.87 (0.36–2.11) | 0.934 |
| Gastric ulcer, n (%) | 11 (2.6) | 8 (1.6) | 0.63 (0.25–1.58) | 0.444 |
| Alcohol disorder, n (%) | 7 (1.7) | 10 (2.1) | 1.25 (0.47–3.32) | 0.837 |
| Inflammatory bowel disease, n (%) | 5 (1.2) | 3 (0.6) | 0.52 (0.12–2.19) | 0.582 |
| CDI treatment | ||||
| Oral vancomycin, n (%) | 257 (60.8) | 333 (68.7) | 1.42 (1.08–1.86) | 0.015 |
| Metronidazole, n (%) | 190 (44.9) | 221 (45.6) | 1.03 (0.79–1.33) | 0.897 |
| Post-infection clinical course and outcomesb) | ||||
| In-hospital death, n (%) | 34 (8.0) | 128 (26.4) | 4.10 (2.74–6.15) | < 0.001 |
| Clinical recovery, n (%) | 356 (84.2) | 331 (68.2) | 0.40 (0.29–0.56) | < 0.001 |
| Hospital transfer, n (%) | 12 (2.8) | 22 (4.5) | 1.63 (0.80–3.33) | 0.242 |
| Total hospital stay (days), median (IQR) | 17.0 (9.0–35.0) | 29.0 (16.0–57.0) | 1.01 (1.01–1.01)a) | < 0.001 |
| ICU stay (days), median (IQR) | 0.0 (0.0–0.0) | 1.0 (0.0–9.0) | 1.87 (1.55–2.26)a) | < 0.001 |
a)Odds ratios for continuous variables (age, Charlson comorbidity index, hospital stay, ICU stay) are presented per 1-unit increase.
b)Intermediate clinical course and post-infection outcomes (hospital stay, ICU stay, in-hospital death) are presented for descriptive characterization but were strictly excluded from multivariable prediction models to prevent circular logic and reverse causality.
Abbreviations: CDI, Clostridioides difficile infection; OR, odds ratio; CI, confidence interval; IQR, interquartile range; SD, standard deviation; ICU, intensive care unit.