Table 4.

Quarterly mortality among ESA responders, acute hyporesponders and chronic hyporesponders

	Chronic Hyporesponders	Acute Hyporesponders	ESA Responders	P Value
Q1 (Months 5–7) % deaths	5.48 % (169/3086)	2.97 % (197/6632)	2.00 % (1631/81,504)	<0.0001
Q2 (Months 8–10) % deaths	4.56 % (125/2741)	3.06 % (189/6167)	2.16 % (1671/77,451)	<0.0001
Q3 (Months 11–13) % deaths	4.61 % (115/2497)	3.30 % (186/5723)	2.49 % (1834/73,559)	<0.0001
Q4 (Months 14, 15) % deaths	2.98 % (67/2250)	2.17 % (116/5334)	1.43 % (997/69,478)	<0.0001

Quarterly mortality was calculated by dividing the total number of deaths over the time period divided by the number of patients alive at the beginning of the time period who were not censored for discontinuation, modality change, or transplant/failed transplant. To avoid immortal time bias, mortality was considered beginning in month 5 (i.e., after the distinction between acute and chronic ESA hyporesponsiveness could be made); patients who died or were censored before 4 months had elapsed were excluded from analyses

P values represent a chi square test