Table 2.

Polysomnogram and clinical metrics by prior PAP use: median [Q1, Q3]/nominal 2-sided p-value from Wilcoxon signed-rank test for paired change from baseline to visit

Endpoint	Prior PAP-treated group			PAP-naïve group
	Baseline (n = 53)	1 year		Baseline (n = 93)	1 year
		Result (n = 41)	Paired change from baseline		Result (n = 78)	Paired change from baseline
Apnea-hypopnea index (events/hour)	52 [35, 63]	16 [10, 32]	−30 [−45, −7] <.001	41 [31, 56]	19 [9, 34]	−19 [−33, −6] <.001
Central apnea index (events/hour)	30 [17, 47]	2 [0, 6]	−24 [−48, −15] <.001	21 [12, 36]	1 [0, 4]	−17 [−30, −10] <.001
Obstructive apnea index (events/hour)	2 [0, 4]	2 [1, 5]	0 [−1, 3] 0.076	2 [1, 4]	4 [1, 10]	2 [−1, 6] <.001
Mixed apnea index (events/hour)	1 [0, 5]	0 [0, 1]	−1 [−5, −0] <.001	1 [0, 4]	0 [0, 1]	−1 [−3, 0] <.001
Hypopnea index (events/hour)	12 [2, 19]	10 [6, 19]	2 [−7, 7] 0.562	12 [4, 20]	8 [4, 17]	−1 [−7, 7] 0.582
4% oxygen desaturation Index (events/hour)	45 [33, 61]	16 [8, 27]	−26 [−42, −6] <.001	35 [24, 51]	17 [8, 29]	−15 [−29, −3] <.001
Arousal index (events/hour)	39 [30, 54]	18 [14, 26]	−18 [−32, −8] <.001	40 [27, 57]	22 [15, 35]	−12 [−33, −4] <.001
Percent of sleep with O2 saturation <90% (%)	12 [4, 27]	5 [1, 13]	−5 [−13, −0] <.001	7 [2, 19]	3 [1, 12]	−3 [−9, 1] <.001
Percent of sleep in N1 (% of sleep)	33 [19, 42]	21 [14, 27]	−7 [−17, 3] 0.023	35 [21, 49]	28 [19, 40]	−4 [−18, 4] 0.002
Percent of sleep in N2 (% of sleep)	51 [42, 58]	58 [48, 65]	4 [−5, 12] 0.116	45 [40, 56]	53 [44, 59]	4 [−3, 13] 0.005
Percent of sleep in N3 (% of sleep)	3 [0, 7]	2 [0, 7]	0 [−1, 1] 0.784	2 [0, 10]	1 [0, 5]	0 [−4, 1] 0.015
Percent of sleep in REM (% of sleep)	10 [5, 16]	15 [6, 21]	4 [−5, 8] 0.251	10 [6, 16]	13 [8, 21]	3 [−2, 11] <.001
Epworth Sleepiness Scale (points)	12 [7, 16]	8 [5, 10]	−3 [−8, 0] <.001	8 [5, 13]	5 [3, 8]	−3 [−6, 0] <.001
Fatigue Severity Scale (points)	5.2 [3.4, 6.2]	4.6 [3.3, 6.0]	−0.2 [−1.4, 0.6] 0.084	4.4 [3.3, 5.7]	3.4 [2.4, 5.1]	−0.5 [−1.6, 0.4] 0.003