Early cardiovascular abnormalities in newly diagnosed obstructive sleep apnea

Figures & data

Table 1 General, hemodynamic, biological, and respiratory characteristics of the global population and according to the severity of OSA (RDI)

	Total (N = 130)	Group A RDI < 37 (N = 65)	Group B RDI > 37 (N = 65)	P value
Age (years)	49 ± 10	48 ± 10	49 ± 10	NS
Gender (% men)	84	80	88	NS
BMI (kg/m^2)	26.5 ± 3	25.6 ± 3	27.5 ± 3.5	0.001
Active smoking (N, %)	26 (20)	14 (21)	12 (18)	NS
Clinic SBP (mmHg)	131 ± 16	131 ± 18	132 ± 14	NS
Clinic DBP (mmHg)	86 ± 10	85 ± 11	87 ± 10	NS
Clinic PP (mmHg)	45 ± 11	46 ± 12	44 ± 10	NS
Clinic HR (bpm)	65 ± 10	65 ± 10	65 ± 10	NS
Daytime SBP (mmHg)	128 ± 14	127 ± 13	128 ± 15	NS
Daytime DBP (mmHg)	84 ± 8	84 ± 7	83 ± 9	NS
Nighttime SBP (mmHg)	113 ± 12	111 ± 12	114 ± 13	NS
Nighttime DBP (mmHg)	72 ± 8	71 ± 8	73 ± 8	NS
Total cholesterol (mmol/L)	5.16 ± 1.03	5.32 ± 1.06	5.06 ± 1.01	NS
LDL cholesterol (mmol/L)	3.22 ± 0.86	3.35 ± 0.91	3.02 ± 0.77	NS
HDL cholesterol (mmol/L)	1.55 ± 0.39	1.57 ± 0.37	1.54 ± 0.4	NS
Triglycerides (mmol/L)	1.2 ± 0.56	1.17 ± 0.34	1.24 ± 0.67	0.09
Glucose (mmol/L)	5.02 ± 0.7	5.0 ± 0.8	5.04 ± 0.5	NS
Creatininemia (μmol/L)	88 ± 13	89 ± 15	86 ± 12	NS
RDI (/h)
Microarousal index (/h) (%)	40 ± 17	28 ± 7	53 ± 14	<0.0001
Mean nocturnal SaO2 (%)	35 ± 14	29 ± 9	42 ± 15	<0.0001
Minimal nocturnal SaO2	93.5 ± 1.8	94 ± 1.6	93 ± 2	NS
SaO2 < 90% (%)	84 ± 6	85.5 ± 5	82.6 ± 7	0.006
	5.7 ± 11.5	3.5 ± 10	8 ± 13	0.03

Note: Results are given as mean ± SD or percentage.

Abbreviation: BMI, body mass index; DBP, diastolic blood pressure; LDL, low-density lipoprotein; HDL, high-density lipoprotein; HR, heart rate; NS, not significant; OSA, obstructive sleep apnea; PP, pulse pressure; RDI, respiratory disturbance index; SaO₂, oxygen saturation; SaO₂ < 90%, percentage of recording time spent at a SaO₂ < 90%; SBP, systolic blood pressure; SD, standard deviation.

Table 2 Cardiovascular parameters in the global population and according to the severity of OSA (RDI)

	Total (N = 130)	Group A RDI < 37 (N = 65)	Group B RDI > 37 (N = 65)	P value
Clinic hypertension (N, %)	45 (35)	18 (28)	27 (41)	0.07
Nondipper SBP (N, %)	49 (38)	18 (28)	31 (48)	0.015
Nondipper DBP (N, %)	37 (29)	13 (20)	24 (37)	0.026
Nondipper SBP or DBP (N, %)	55 (42)	22 (34)	34 (52)	0.025
LVEF (%)	58 ± 6	59 ± 6	57 ± 7	NS
IVS (mm)	8.5 ± 1	8.1 ± 1.1	8.8 ± 1.2	0.005
LVPW (mm)	9.0 ± 1.1	8.7 ± 1.2	9.2 ± 1.2	0.01
LVM (g)	168 ± 41	159 ± 41	178 ± 38	0.013
LVMI (g/m^2)	87 ± 19	83 ± 20	90 ± 18	0.05
LVMI-height^2.7 (g/m)	38 ± 8	36 ± 8	40 ± 7	0.014
LVH ind^2.7 (N, %)	11 (9.5)	4 (7)	7 (12)	0.19
RWT (%)	36 ± 5.5	35 ± 4.6	37 ± 6	0.039
RWT > 0.45 (N, %)	7 (6)	2 (3.5)	5 (8.5)	0.16
Clinic PP (mmHg)	45 ± 11	46 ± 12	44 ± 10	NS
Increased clinic PP (N, %)	8 (6)	5 (7)	3 (4.5)	NS
PWV (m/s)	9.1 ± 1.5	8.9 ± 1.6	9.2 ± 1.4	NS
Increased PWV (N, %)	5 (8)	1 (1.5)	4 (6)	0.18
Carotid IMT (mm)	0.65 ± 0.15	0.64 ± 0.16	0.66 ± 0.13	NS
Increased carotid IMT (N, %)	30 (23)	14 (21)	16 (25)	NS
Carotid plaques (N, %)	25 (19)	13 (20)	12 (18)	NS

Note: Results are given as mean ± SD or percentage.

Abbreviations: DBP, diastolic blood pressure; IMT, intima-media thickness; IVS, interventricular septum; LVEF, left ventricular ejection fraction; LVH, left ventricular hypertrophy; LVM, left ventricular mass; LVMI, left ventricular mass index; LVPW, left ventricular posterior wall; NS, not significant; OSA, obstructive sleep apnea; PP, pulse pressure; PWV, pulse wave velocity; RDI, respiratory disturbance index; RWT, relative wall thickness; SBP, systolic blood pressure; SD, standard deviation.

Figure 1 Relationship between carotid IMT and mean nocturnal SaO₂ (r = −0.21, P = 0.017).

Abbreviations: IMT, intima-media thickness; SaO₂, oxygen saturation.

Table 3 Factors related to carotid hypertrophy

	Carotid hypertrophy (N = 30)	Normal IMT (N = 100)	P
Age (years)	55 ± 8	47 ± 10	<0.0001
Clinic SBP (mmHg)	140 ± 18	128 ± 14	0.002
Mean nocturnal SaO2 (%)	92.6 ± 1.7	93.8 ± 1.7	0.002
Minimal nocturnal SaO2 (%)	82.2 ± 8.1	84.7 ± 5.5	0.055
SaO2 < 90% (%)	10 ± 16	5.5 ± 9.5	0.020

Note: Results are given as mean ± SD.

Abbreviations: IMT, intima media thickness; SaO₂, oxygen saturation; SaO₂ < 90%, percentage of recording time spent at a SaO₂ < 90%; SBP, systolic blood pressure; SD, standard deviation.

Figure 2 LVMI-height^2.7 according to the mean nocturnal SaO₂ group (median) (P = 0.003 between groups 1 and 2).

Notes: Group 1: mean nocturnal SaO₂ < 93.5%; Group 2: mean nocturnal SaO₂ ≥ 93.5%.
Abbreviations: LVMI, left ventricular mass index; SaO₂, oxygen saturation.

Table 4 Cardiovascular anomalies according to the severity of OSA (mean nocturnal SaO₂)

	Group 1 SaO2 < 93.5% (N = 68)	Group 2 SaO2 > 93.5% (N = 62)	P value
Clinic hypertension (N, %)	27(40)	18 (29)	0.14
Clinic or ABPM hypertension (N, %)	55 (81)	43 (69)	0.09
Nondipper SBP or DBP	33 (48)	23 (38)	0.13
LVMI-height^2.7 (g/m)	40 ± 8	36 ± 8	0.003
LVH ind^2.7 (N, %)	8 (12)	3 (4.8)	0.12
Carotid IMT (mm)	0.67 ± 0.14	0.63 ± 0.15	0.13
Increased carotid IMT (N, %)	20 (29.5)	10 (16)	0.05
Carotid plaques (N, %)	15 (22)	10 (16)	NS

Note: Results are given as mean ± SD or percentage.

Abbreviations: ABPM, ambulatory blood pressure monitoring; DBP, diastolic blood pressure; IMT, intima media thickness; LVH, left ventricular hypertrophy; LVMI, left ventricular mass index; NS, not significant; OSA, obstructive sleep apnea; SaO₂, oxygen saturation; SBP, systolic blood pressure; SD, standard deviation.