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)

	Events		Odds ratios
	Overdose patients (n=552)	Controls (n=11 040)	Crude	Adjusted (95% CI)
Primary outcome
Neurological:
Encephalopathy	<5	<5	n/a	n/a
Secondary outcome
Respiratory outcomes:
Respiratory failure	14	23	12.46	6.21 (2.24 to 17.21)
Aspiration pneumonia	5	19	5.30	2.96 (0.90 to 9.71)
ARDS	<5	9	n/a	n/a
Pulmonary haemorrhage	0	0	n/a	n/a
Cardiac outcomes:
Cardiac arrest	0	5	n/a	n/a
Ventricular arrhythmia	0	5	n/a	n/a
Heart failure	9	95	1.93	0.99 (0.45 to 2.15)
Other outcomes:
Rhabdomyolysis	5	19	5.30	3.08 (0.87 to 10.88)
Acute renal failure	16	103	3.18	1.66 (0.90 to 3.05)
Paraplegia or tetraplegia	<5	6	n/a	n/a
All-cause mortality	22	96	4.73	2.13 (1.18 to 3.86)
Composite outcome*	59	309	4.14	2.15 (1.48 to 3.12)
Serious adverse events†	315	3489	2.84	1.97 (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.