Table 2.

Unadjusted Bivariate Differences Using Poisson Analysis Overall and by Subsets Based on Disability Scores

Pharmacology Prescription Variables After Index Date	Opioid Naïve (mean and 95% CI/Proportions) (n = 224)	Prior Opioid Users (mean and 95% CI/Proportions) (n = 485)	P value
Total opioid prescriptions	2.16 (1.97, 2.36)	10.06 (9.78, 10.34)	< 0.01
Total NSAID prescriptions	4.04 (3.79, 4.31)	6.19 (5.97, 6.42)	< 0.01
Total muscle relaxer prescriptions	1.57 (1.41, 1.74)	3.22 (3.07, 3.39)	< 0.01
Total prescriptions for any other pain medication	33.62 (32.87, 34.39)	72.22 (71.47, 72.98)	< 0.01
Proportion still taking opioids at 1 year after index date*
Yes	101	290	< 0.01
No	123	195
Oswestry Score of 16 or less (n = 358)
Total opioid prescriptions	1.78 (0.04, 3.52)	5.43 (4.04, 6.82)	< 0.01
Total NSAID prescriptions	3.86 (3.13, 4.59)	4.97 (4.39, 5.55)	0.02
Total muscle relaxer prescriptions	1.50 (1.04, 1.97)	1.91 (1.54, 2.28)	0.18
Total prescriptions for any other pain medication	31.69 (24.17, 39.21)	47.74 (41.75, 53.73)	< 0.01
Proportion still taking opioids at 1 year after index date*
Yes	60	117	0.06
No	79	102
Oswestry score of 17 or greater (n = 351)
Total opioid prescriptions	2.76 (−1.96, 7.49)	13.87 (11.20, 16.54)	< 0.01
Total NSAID prescriptions	4.33 (3.00, 5.66)	7.20 (6.44, 7.95)	< 0.01
Total muscle relaxer prescriptions	1.67 (0.41, 2.93)	4.30 (3.59, 5.02)	< 0.01
Total prescriptions for any other pain medication	36.78 (17.18, 56.37)	92.37 (81.29, 103.44)	< 0.01
Proportion still taking opioids at 1 year after index date*
Yes	41	173	< 0.01
No	44	93

^*No statistical control for covariates. CI, confidence interval; NSAID, nonsteroidal anti-inflammatory drug; ODI, Oswestry Disability Index.

Of those with ODI scores of 16 or less (n = 358), 139 were opioid naïve and 219 used opioids previously. Of those with ODI scores of 17 or greater (n = 351), 85 were opioid naïve and 266 used opioids previously.

Bolded P values reflect statistical significance < 0.05.