Table 1. Association between Anti-Streptolysin O (ASLO) and anti-PDI Antibodies.

	ASLO positive$	ASLO negative	Odds Ratio (95% CI)	P value
Anti-bovine PD I ¶
Exploratory sample (Stanford)	33.8% (65)	14.7% (245)	3.0 (1.6, 5.5)	<0.0001
Replication (Stanford)	33.3% (99)	11.4% (273)	3.9 (2.2, 6.8)	<0.0001
Wisconsin Sleep Cohort	38.6% (446)	10.2% (2401)	4.6 (3.7, 5.8)	<0.0001
All samples	37.2% (610)	12.2% (2919)	4.2 (3.5, 5.2)	<0.0001
Anti- human PDI #
Exploratory sample (Stanford)	8.3% (24)	7.5% (80)	1.1 (0.2, 5.8)	0.92
Replication (Stanford)	5.9% (85)	3.4% (263)	1.7 (0.6, 5.4)	0.32
Wisconsin Sleep Cohort	15.4% (421)	5.8% (2114)	3.0 (2.1, 4.1)	<0.0001
All samples	13.6% (530)	5.6% (2457)	2.7 (2.0, 3.6)	<0.0001

Results are presented as percentages of positive anti-PDI sera (number of all sera in this subgroup).

^$ASLO positivity defined as ASLO ≥200 for participants ages 6–40 years and ASLO ≥100 for participants older than 40 years, as recommended [40].

^¶Anti-bovine PDI defined as positive if ELISA OD ≥0.5.

^#Anti-human PDI defined as positive if ELISA OD ≥0.75.