TABLE 4.

Comparison of Annual Health Care Costs Between Early and Late TKI Initiator Patients

	Average Annual Costs, $ (mean ± SD)		Unadjusted		Adjusted
	Patients Who Initiated TKI Therapy		Cost Differencea [A] – [B]	P Value	Cost Differencea (beta coefficient)	P Value
	≤ 1 month from First CML Diagnosis (n = 397) [A]	Within > 1-12 months from First CML Diagnosis (n = 80) [B]
Medical costs	18,022.82 ± 47,196.26	37,385.61 ± 102,911.10	-19,362.79	0.03b	-7,581.78 (-.29)	0.22
TKI pharmacy costs	100,261.80 ± 32,276.67	85,516.64 ± 37,864.63	14,745.16	< 0.01b	9,922.02 (.11)	< 0.05b
Non-TKI pharmacy costs	2,580.74 ± 6,031.22	2,644.48 ± 4,655.23	-63.74	0.92	-217.17 (-.05)	0.80
Total all-cause health care costs	120,865.40 ± 57,195.23	125,546.70 ± 108,251.90	-4,681.30	0.70	-2,679.20 (-.02)	0.79

^a Cost differences < 0 indicate that late initiators incurred higher health care costs. Cost differences were estimated using multivariable generalized linear models with a gamma distribution and a log link.

^b Significant at the 5% level.

CML = chronic myeloid leukemia; SD = standard deviation; TKI = tyrosine kinase inhibitor.