Table 1. Characteristics of TTP remission cohort ^a .

	Relapse (n = 16)	Non-Relapse (n = 22)	p-value
Age ± SD	43.9 ± 15.9	45.3 ± 12.8	0.362 b
Race/Ethnicity % [number]			0.199 c
Caucasian	43.8% [7]	72.7% [16]
African American	43.8% [7]	22.7% [5]
American Indian	0.06% [1]	0.05% [1]
Hispanic	0.06% [1]	0% [0]
Sex % [number]
Female	68.8% [11]	95.5% [21]	0.065 c
Median years follow-up [range]	9.8 [3.6–26.6]	6.8 [0.8–12.8]	0.0325 d
Median years since last episode [range]	3.4 [0.2–13.2]	6.8 [0.8–12.8]	0.076 d

^a Individuals with a history of clinically diagnosed TTP (<10% ADAMTS13 activity during a prior acute episode), in remission for at least 2 months, who fail to meet criteria for any known rheumatic disease;

^b t-test;

^c Fisher’s exact test;

^d Kolmogorov-Smirnov test.