Table 1.
Risk of sARF associated with selected co-morbidities among adult residents of the Calgary Health Region, Canada
| Underlying condition | Number of patients with sARF (n = 240) | Estimated number with underlying condition at risk in CHR | Annual incidence (per 100,000 population) | Relative riska (Exact 95% CI) |
| Heart disease | 120 | 85,576 | 140 | 24.0 (18.5–31.2)b |
| Stroke | 44 | 21,394 | 206 | 22.0 (15.6–31.0)b |
| Chronic pulmonary disease | 83 | 68,461 | 121 | 16.0 (12.1–21.0)b |
| Diabetes mellitus | 72 | 85,576 | 84 | 10.3 (7.7–13.6)b |
| Cancer | 38 | 42,788 | 89 | 9.2 (6.3–13.1)b |
| Connective tissue disease | 12 | 21,394 | 56 | 5.2 (2.7–9.3)b |
| Chronic kidney disease | 45 | 96,273 | 47 | 4.9 (3.5–6.8)b |
| Alcohol abuse | 57 | 145,480 | 39 | 4.3 (3.1–5.8)b |
aRelative risk calculated by ((Number of sARF patients with underlying condition/Number at-risk with underlying condition in CHR)/(Number of sARF patients without underlying condition/Number at-risk without underlying condition in CHR)). bp value < 0.0001 for each underlying condition relative risk. Underlying conditions were defined by using the Charlson Co-morbidity Index [25]. The presence of alcohol abuse was defined by documentation in patient medical record or by history. CHR, Calgary Health Region; CI, confidence interval; sARF, severe acute renal failure.