Improved cognitive functions after treatment with an oral appliance in obstructive sleep apnea

Figures & data

Figure 1 The oral appliances used in this study were manufactured in one-piece heat-cured acrylic polymer.

Table 1 Somnographic values at baseline and after 6 months of treatment in patients with obstructive sleep apnea (OSA) who completed the follow-up

	Baseline			After 6 months
	Total n = 45	Moderate OSA n = 15	Severe OSA n = 30	Total n = 45	Moderate OSA n = 15	Severe OSA n = 30
AHI	40.9 (16.0)	23.0 (2.7)	48.6 (12.7)	18.0 (17.3)a	11.2 (7.8)b	21.5 (19.6)a
ODI	39.7 (21.0)	22.3 (9.8)	47.4 (20.1)	17.3 (17.2)a	10.5 (7.7)b	20.7 (19.6)a

Notes: Expressed as means (SD); Wilcoxon signed ranks test;

a statistical significance in results between before and after treatment P <; 0.001;

b statistical significance in results between before and after treatment P <; 0.01.

Abbreviations: OSA, Obstructive sleep apnea; AHI, apnea/hypopnea index; ODI, oxygen saturation index.

Table 2 Cognitive function tests before and after treatment of obstructive sleep apnea with an oral appliance

	Before n = 43	After n = 43	Difference before and after 6 months, P-value
WM
Memory scorea	88.2 (10.8)	81.8 (11.5)	NS
Distraction taska	85.4 (8.1)	87.7 (8.2)	P <; 0.001
CPT-IP
Correct countinga	53.1 (22.9)	62.7 (19.6)	P <; 0.001
False alarma	17.8 (12.8)	18.3 (13.6)	NS
D’primeb	1.201 (0.669)	1.419 (0.766)	P = 0.015
TMT
Part Ac	34.6 (11.3)	29.0 (11.0)	P <; 0.001
Part Bc	84.9 (32.8)	75.2 (27.3)	NS

Notes: Expressed as means (SD); Wilcoxon signed ranks test;

a expressed as a percentage;

b quotient hits/false alarms;

c expressed as seconds.

Abbreviations: WM, Working Memory test; CPT-IP, Continuous Performance Test, Identical Pairs Version; TMT, Trail-Making Test.

Table 3 Cognitive function tests before and after treatment with an oral appliance in patients with severe obstructive sleep apnea

	Before n = 28	After n = 28	Difference before and after 6 months, P-value
WM
Memory scorea	81.3 (14.4)	82.4 (10.7)	NS
Distraction taska	83.8 (8.7)	87.6 (8.5)	P <; 0.001
CPT-IP
Correct countinga	57.1 (21.2)	66.8 (19.2)	P <; 0.001
False alarma	18.0 (11.9)	19.9 (15.4)	NS
D’primeb	1.267 (0.780)	1.510 (0.869)	P = 0.031
TMT
Part Ac	33.1 (10.1)	27.6 (8.9)	P <; 0.001
Part Bc	84.1 (35.9)	70.9 (25.9)	P <; 0.006

Notes: Expressed as means (SD); Wilcoxon signed ranks test;

a expressed as a percentage;

b quotient hits/false alarms;

c expressed as seconds.

Abbreviations: WM, Working Memory test; CPT-IP, Continuous Performance Test; Identical Pairs Version; TMT, Trail-Making Test.

Table 4 Difference of somnographic treatment outcome and the influence on cognitive function tests

	Normalized (AHI ≤ 10) n = 24	Not normalized (AHI >; 10) n = 19	Difference between responders vs nonresponders, P-value
WM
Memory scorea	1.1 (14.6)	−1.5 (12.4)	NS
Distraction taska	2.6 (3.6)	0.4 (6.8)	NS
CPT-IP
Correct countinga	10.5 (15.6)	8.4 (16.2)	NS
False alarma	1.8 (14.2)	−0.6 (18.4)	NS
D’primeb	0.364 (0.593)	0.158 (0.543)	NS
TMT
Part Ac	−6.3 (9.5)	−3.3 (7.8)	NS
Part Bc	−11.0 (26.9)	−3.2 (32.1)	NS

Notes: Expressed as means (SD); Chi-square test. Responders = normalized;

a expressed as a percentage;

b quotient hits/false alarms;

c expressed as seconds.

Abbreviations: AHI, Apnea/hypopnea index; WM, Working Memory test; CPT-IP, Continuous Performance Test, Identical Pairs Version; TMT, Trail-Making Test.