Table 5

Risk of neurological, respiratory, cardiac and other outcomes in 1 year following hospital admission for accidental opioid overdose in comparison to controls among patients with long-term prescription opioid use (≥180 days)

EventsOdds ratios
Overdose patients
(n=11 040)
(95% CI)
Primary outcome
Secondary outcome
Respiratory outcomes:
  Respiratory failure142312.466.21 (2.24 to 17.21)
  Aspiration pneumonia5195.302.96 (0.90 to 9.71)
  Pulmonary haemorrhage00n/an/a
Cardiac outcomes:
  Cardiac arrest05n/an/a
  Ventricular arrhythmia05n/an/a
  Heart failure9951.930.99 (0.45 to 2.15)
Other outcomes:
  Rhabdomyolysis5195.303.08 (0.87 to 10.88)
  Acute renal failure161033.181.66 (0.90 to 3.05)
  Paraplegia or tetraplegia<56n/an/a
All-cause mortality22964.732.13 (1.18 to 3.86)
Composite outcome*593094.142.15 (1.48 to 3.12)
Serious adverse events†31534892.841.97 (1.62 to 2.39)
  • OR estimates have been omitted, and replaced with ‘n/a’ for ‘not available’, for outcomes where estimation was not possible due to a small number of events in one or more exposure groups. 

  • *The ‘composite outcome’ was defined as an inpatient hospital diagnosis of one or more of the following: encephalopathy, ARDS, respiratory failure, pulmonary haemorrhage, aspiration pneumonia, cardiac arrest, ventricular arrhythmia, heart failure, rhabdomyolysis, acute renal failure or death. 

  • †Serious adverse events were defined as all-cause hospitalisation or death.

  • ARDS, adult respiratory distress syndrome.