Table 4.

Odds ratios, risk ratios, absolute risk increase, and relative risk increase for revision surgery for selected outcomes.

	Odds ratio (95% CI)	P value	Risk ratio (95% CI)	Absolute risk increase, %	Relative risk increase (%)
Complications within 30 days of surgery
Deep vein thrombosis	1.17 (0.79-1.73)	.43	1.03 (0.95-1.11)	0.06	12.5
Pulmonary embolism	1.47 (0.93-2.34)	.10	1.08 (0.96-1.21)	0.11	31.4
Surgical site infection	1.27 (0.97-1.66)	.07	1.08 (1.01-1.14)	0.31	27.4
New neurological disorder	1.58 (91.21-2.08)	<.01	1.13 (1.05-1.21)	0.48	40
Urinary tract infection	1.07 (0.82-1.42)	.60	1.00 (0.95-1.06)	0.02	2.2
Cerebral vascular Accident	1.51 (0.60-3.46)	.33	1.14 (0.93-1.40)	0.07	46.6
Myocardial infarction	2.79 (1.52-5.10)	<.01	1.29 (1.04-1.63)	0.14	60.8
Incidental durotomy	2.02 (1.72-2.38)	<.01	1.17 (1.12-1.23)	1.65	48.5
Hematoma	1.04 (0.72-1.51)	.80	1.01 (0.94-1.09)	0.04	8
Pneumonia	2.14 (1.43-3.19)	<.01	1.27 (1.11-1.45)	0.38	61.2
Destination
30-day readmission to hospital	1.16 (1.04-1.30)	<.01	1.05 (1.02-1.07)	1.22	18.3
30-day return to OR	1.34 (1.14-1.58)	<.01	1.07 (1.03-1.11)	0.78	25.5
Revision surgery within 3 mo	1.46 (1.20-1.78)	<.01	1.09 (1.05-1.15)	0.93	32.7

Control variables for odds ratio analyses include age, gender, race, ethnicity, educational status, employment status, ASA grade, dominant symptoms, baseline disability score, baseline pain intensity score for back and leg, baseline quality of life score, diabetes, coronary artery disease, peripheral vascular disease, anxiety, depression, osteoarthritis, chronic renal disorder, chronic obstructive pulmonary disease, osteoporosis, Parkinson disease, weakness, and numbness.

CI confidence interval, OR operating room, ASA American Society of Anesthesiologists.