Table 3.
Number of hospital admissions for accidental opioid overdose and outcomes evaluated during overdose admission, by year
| 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2006–2015 | |
| Overdose hospitalisations (n): | |||||||||||
| Admission | ~178 | 166 | ~200 | 211 | 207 | 251 | 274 | 284 | 290 | 372 | 2433 |
| Readmission | <5 | 6 | <5 | 15 | 8 | 17 | 15 | 18 | 16 | 21 | 121 |
| All | 180 | 172 | 203 | 226 | 215 | 268 | 289 | 302 | 306 | 393 | 2554 |
| Type of opioid overdose * (n): | |||||||||||
| Heroin | 28 | 27 | 34 | 28 | 28 | 35 | 35 | 56 | 67 | 96 | 434 |
| Methadone | 30 | 26 | 36 | 32 | 31 | 36 | 54 | 47 | 65 | 70 | 427 |
| Synthetic opioid† | 9 | <7 | <7 | 8 | 11 | 10 | 14 | 12 | 19 | 37 | 130 |
| Other opioid‡ | 80 | 82 | 81 | 109 | 101 | 135 | 143 | 147 | 121 | 148 | 1147 |
| Unspecified/other | 46 | 41 | 52 | 57 | 53 | 60 | 55 | 56 | 53 | 76 | 549 |
| Number of outcomes * (n): | |||||||||||
| Encephalopathy | 7 | <5 | <5 | <5 | <5 | 8 | 14 | 11 | 8 | 17 | 77 |
| Respiratory failure | <6 | <6 | 7 | 8 | 7 | 10 | 24 | 16 | 17 | 37 | 134 |
| Aspiration pneumonia | 20 | 17 | 18 | 21 | 33 | 31 | 38 | 30 | 36 | 44 | 288 |
| Rhabdomyolysis | 7 | 6 | 10 | 11 | 12 | 10 | 17 | 12 | 19 | 20 | 124 |
| Acute renal failure | 13 | 15 | 9 | 16 | 20 | 25 | 30 | 24 | 34 | 51 | 237 |
| Death in hospital | 8 | <5 | 7 | 7 | <5 | 7 | 9 | 9 | 12 | 13 | 80 |
| Composite outcome§ | |||||||||||
| Admission with ≥1 event | 42 | 37 | 36 | 50 | 54 | 68 | 87 | 72 | 82 | 109 | 637 |
| Total events | 69 | 55 | 62 | 76 | 83 | 108 | 150 | 111 | 142 | 199 | 1055 |
| Incidence proportion¶ (%): | |||||||||||
| Encephalopathy | 3.9 | n/a | n/a | n/a | n/a | 3.0 | 4.8 | 3.6 | 2.6 | 4.3 | 3.0 |
| Respiratory failure | n/a | n/a | 3.4 | 3.5 | 3.3 | 3.7 | 8.3 | 5.3 | 5.6 | 9.4 | 5.3 |
| Aspiration pneumonia | 11.1 | 9.9 | 8.9 | 9.3 | 15.3 | 11.6 | 13.1 | 9.9 | 11.8 | 11.2 | 11.3 |
| Rhabdomyolysis | 3.9 | 3.5 | 4.9 | 4.9 | 5.6 | 3.7 | 5.9 | 4.0 | 6.2 | 5.1 | 4.9 |
| Acute renal failure | 7.2 | 8.7 | 4.4 | 7.1 | 9.3 | 9.3 | 10.4 | 7.9 | 11.1 | 13.0 | 9.3 |
| Death in hospital | 4.4 | n/a | 3.4 | 3.1 | n/a | 2.6 | 3.1 | 3.0 | 3.9 | 3.3 | 3.1 |
| Composite outcome† | |||||||||||
| Admission with ≥1 event | 23.3 | 21.5 | 17.7 | 22.1 | 25.1 | 25.4 | 30.1 | 23.8 | 26.8 | 27.7 | 24.9 |
*To avoid small cell sizes, less common types of overdose (opium) and outcome (eg, cardiac outcomes) have been omitted, or a value of '<5' was entered for counts and corresponding proportions were listed as ’n/a'. Where counts <5 could be deduced, values of '<6' or '<7' have been used or a tilde (~) was used for approximate values.
†Includes buprenorphine, fentanyl, pethidine and tramadol.
‡Includes codeine, hydromorphone, morphine and oxycodone.
§The ‘composite outcome’ included encephalopathy, ARDS, respiratory failure, pulmonary haemorrhage, aspiration pneumonia, cardiac arrest, ventricular arrhythmia, heart failure, rhabdomyolysis, acute renal failure or death (‘total events’ does not equal the sum of the other events reported, because some outcomes included in the composite outcome were not reported separately).
¶Incidence proportion describes the percentage of hospital admissions for accidental opioid overdose in which patients were diagnosed with each type of outcome in each period.
ARDS, adult respiratory distress syndrome.