Characteristics of patients with evidence of injection drug use, comparing those with and without infective endocarditis
| Characteristic | No. (%) of patients* | Standardized difference,† % | |
|---|---|---|---|
| Injection drug use without infective endocarditis n = 59 796 | Injection drug use with infective endocarditis n = 733 | ||
| Demographic data | |||
| Age at cohort entry, yr | |||
| Mean ± SD, yr | 40.18 ± 10.79 | 36.33 ± 9.45 | 38 |
| Median (IQR), yr | 42 (31–50) | 36 (28–44) | 42 |
| 18–25 | 7701 (12.9) | 99 (13.5) | 2 |
| 26–35 | 13 014 (21.8) | 256 (34.9) | 30 |
| 36–45 | 14 892 (24.9) | 230 (31.4) | 14 |
| 46–55 | 24 189 (40.5) | 148 (20.2) | 45 |
| Sex, female | 26 324 (44.0) | 390 (53.2) | 18 |
| Residential status | |||
| Urban | 51 756 (86.6) | 640 (87.3) | 2 |
| Rural | 8011 (13.4) | 93 (12.7) | 2 |
| Missing | 29 (0.0) | 0 (0.0) | 3 |
| Socioeconomic status | |||
| 1 (lowest) | 23 187 (38.8) | 320 (43.7) | 10 |
| 2 | 12 876 (21.5) | 162 (22.1) | 1 |
| 3 | 10 365 (17.3) | 113 (15.4) | 5 |
| 4 | 7531 (12.6) | 77 (10.5) | 7 |
| 5 (highest) | 5837 (9.8) | 61 (8.3) | 5 |
| Comorbidities | |||
| Alcohol abuse | 3658 (6.1) | 15 (2.0) | 21 |
| Bipolar disorder | 733 (1.2) | < 6‡ | 7 |
| Chronic liver disease | 4220 (7.1) | 22 (3.0) | 19 |
| Depression and/or anxiety | 11 770 (19.7) | 120 (16.4) | 9 |
| Hepatitis B | 165 (0.3) | 0 (0.0) | 7 |
| Hepatitis C | 8609 (14.4) | 135 (18.4) | 11 |
| HIV | 2209 (3.7) | 46 (6.3) | 12 |
| Schizophrenia | 1065 (1.8) | < 6‡ | 10 |
| Self-harm | 8244 (13.8) | 94 (12.8) | 3 |
| Medication use | |||
| Antibiotics | 14 544 (24.3) | 223 (30.4) | 14 |
| Anticoagulants | 590 (1.0) | 15 (2.0) | 9 |
| Antipsychotics | 9239 (15.5) | 94 (12.8) | 8 |
| Benzodiazepines | 12 909 (21.6) | 144 (19.6) | 5 |
| Lithium | 613 (1.0) | < 6‡ | 7 |
| Opioids | 23 006 (38.5) | 366 (49.9) | 23 |
| General measures of comorbidity | |||
| No. of unique drug prescriptions filled in 1 year | |||
| Mean ± SD | 4.08 ± 5.59 | 3.85 ± 4.80 | 4 |
| Median (IQR) | 1 (0–7) | 2 (0–6) | 7 |
| No. of hospital admissions in 1 year | |||
| Mean ± SD | 1.17 ± 2.29 | 1.10 ± 1.95 | 3 |
| Median (IQR) | 0 (0–1) | 0 (−1) | 1 |
| No. of emergency department visits in 1 year | |||
| Mean ± SD | 4.58 ± 8.43 | 5.01 ± 6.43 | 6 |
| Median (IQR) | 2 (1–5) | 3 (1–7) | 29 |
| No. of family physician visits in 1 year | |||
| Mean ± SD | 21.05 ± 25.07 | 22.78 ± 24.76 | 7 |
| Median (IQR) | 11 (5–27) | 13 (5–33) | 7 |
Note: HIV = human immunodeficiency virus, IQR = interquartile range, SD = standard deviation.
↵* Unless stated otherwise.
↵† The standardized difference is the difference between group means expressed as a percentage of the pooled standard deviation. Standardized differences greater than 10% represent meaningful imbalances.
↵‡ In accordance with ICES privacy policies, cell sizes ≤ 5 cannot be reported, and are instead expressed here as < 6.