Table 2

Preoperative univariate associations by chronic kidney disease stage.

	Stage 1 (n = 76,137)			Stage 2 (n = 92,698)			Stage 3a (n = 20,926)			Stage 3b (n = 7551)			Stage 4 (n = 1552)			Stage 5 (n = 869)
Variable	Steroid (n = 3413)	No Steroid (n = 72,724)	P Value	Steroid (n = 4351)	No Steroid (n = 88,347)	P Value	Steroid (n = 1368)	No Steroid (n = 19,558)	P Value	Steroid (n = 593)	No Steroid (n = 6958)	P Value	Steroid (n = 155)	No Steroid (n = 1397)	P Value	Steroid (n = 45)	No Steroid (n = 824)	P Value
Sex (women)	1931	35,978	4.65E−16	2786	46,801	<2.2e−16	916	11,455	7.49E−10	372	4411	0.756	90	799	0.864	13	299	0.343
Diabetes	625	11,349	3.13E−05	810	16,171	0.602	335	5642	0.00052	236	2620	0.3104	65	709	0.042	12	339	0.0612
Smoker	768	21,263	<2.2E−16	571	13,854	4.06E−06	123	2327	0.00094	39	694	0.0059	11	191	0.0227	12	149	0.1665
Dyspnea	318	3378	<2.2E−16	445	5474	<2.2E−16	203	1848	1.055E−09	79	794	0.1604	28	177	0.07879	4	84	1
Independent functional status	3114	70,062	<2.2E−16	4074	85,548	<2.2E−16	1297	18,725	0.03438	534	6528	0.0002586	135	1266	0.1427	37	687	1
COPD	344	3050	<2.2E−16	483	4446	<2.2E−16	172	1323	1.274E−13	40	569	0.2388	17	90	0.04377	5	64	0.3936
CHF	15	127	0.001853	44	322	1.48E−08	12	158	0.7545	9	113	1	6	47	0.6451	2	47	1
Hypertension	1878	33,571	<2.2E−16	2965	55,310	9.49E−14	1093	15,806	0.4145	511	6060	0.5244	136	1268	0.2473	42	673	0.04524
Dialysis	2	19	0.2421	4	31	0.08007	0	21	0.3962	0	13	0.6171	6	113	0.07784	38	630	0.2763
Sepsis	154	1289	<2.2E−16	85	767	1.06E−10	16	229	1	13	122	0.419	4	83	0.0968	4	88	1
Disseminated cancer	387	1485	<2.2E−16	167	1059	<2.2E−16	47	291	1.04E−06	21	116	0.003216	3	33	1	2	16	0.238
Superficial wound infection	1	12	0.4615	0	5	1	0	0	1	0	2	1	0	0	1	0	0	1
Deep wound infection	3	51	0.7396	3	23	0.1247	0	6	1	0	3	1	0	3	1	0	1	1
Weight loss >10%	68	591	2.79E−10	31	425	0.04443	18	88	0.000167	10	31	0.000994	6	19	0.032	0	20	0.6186
Bleeding disorder	121	992	<2.2E−16	154	1636	9.80E−13	72	589	1.95E−05	34	248	0.01241	9	90	0.8637	2	72	0.4194
Age ≥70 y	369	5114	3.88E−15	1748	32,244	1.04E−06	798	10,904	0.06311	322	4644	1.76E−09	94	844	1	10	224	0.6047
Albumin <3.4 g/dL	421	3029	<2.2E−16	290	2410	<2.2E−16	81	761	0.00412	58	396	0.001283	24	237	0.631	19	233	0.4008
WBC >11,000/µL	578	5770	<2.2E−16	583	4940	<2.2E−16	198	1288	<2.2E−16	83	525	4.15E−07	32	142	0.00044	5	83	0.8004
Platelets <150,000/µL	280	3028	<2.2E−16	276	4262	1.29E−05	101	1242	0.1536	52	547	0.4792	21	151	0.3489	11	161	0.4451
BUN >23 mg/dL	206	2327	2.31E−16	658	9098	<2.2E−16	523	6739	0.005498	404	4491	0.04341	139	1223	0.4219	42	619	0.003679
BMI ≥30	1498	34,825	1.08E−05	2070	43,256	0.0927	655	10,475	2.91E−05	265	3851	2.29E−06	60	749	0.0003443	10	361	0.004889

Abbreviations: BMI, body mass index; BUN, blood urea nitrogen; CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; WBC, white blood cells.
Note: Comparison of preoperative variables between lumbar spine fusion patient groups stratified by CKD stage. For each CKD stage, patients with reported chronic steroid use were compared with patients without chronic steroid use using Fisher exact tests. Statistical significance was defined as P value ≤0.05.