Table 1.
Baseline characteristics of patients with resistant hypertension (RH).
| Non obstructive sleep apnea (OSA) patients | OSA patients | P-value | |
|---|---|---|---|
| n | 25 | 37 | |
| Age (years) | 58 ± 11 | 60 ± 9 | 0.45 |
| Male [% (n)] | 64.0 (16) | 86.5 (32)* | 0.038 |
| BMI (kg/m2) | 29.4 [26.5; 31.2] | 28.6 [27.1; 31.0] | 0.55 |
| Waist circumference (cm) | 104 [97; 110] | 105 [99; 113] | 0.59 |
| History | |||
| Smoking [% (n)] | 52 (13) | 57 (21) | 0.50 |
| Alcohol [% (n)] | 32 (8) | 30 (11) | 0.85 |
| Metabolic syndromea [% (n)] | 60 (15) | 84 (31)* | 0.036 |
| Dyslipidemia [% (n)] | 44 (11) | 38 (14) | 0.63 |
| MI [% (n)] | 4 (1) | 8 (3) | 0.64 |
| Stroke/TIA [% (n)] | 4 (1) | 14 (5) | 0.39 |
| Sleep studies | |||
| AHI (n/h) | 8.2 [5.4; 13.2] | 37.6 [25.4; 51.8]* | <0.001 |
| Mean SaO2 (%) | 93.5 ± 1.9 | 92.7 ± 2.0 | 0.11 |
| SaO2 < 90% (%) | 0.4 [0.1; 1.3] | 5.2 [1.6; 19]* | <0.001 |
| Epworth sleepiness scale | 9.0 ± 4.4 | 8.2 ± 4.2 | 0.53 |
| Office BPb | |||
| SBP (mmHg) | 150 [143; 161] | 156 [145; 161] | 0.56 |
| DBP (mmHg) | 89 ± 14 | 92 ± 11 | 0.49 |
| MABP (mmHg) | 111 ± 14 | 112 ± 10 | 0.63 |
| HR (pbm) | 63 [57; 72] | 68 [60; 75] | 0.12 |
| 24-h BP | |||
| SBP (mmHg) | 140 [135; 148] | 139 [133; 150] | 0.70 |
| DBP (mmHg) | 81.1 ± 9.4 | 82.8 ± 10 | 0.50 |
| MABP (mmHg) | 101.6 ± 8.7 | 102.2 ± 9.0 | 0.79 |
| HR (bpm) | 71.0 ± 11.1 | 69.8 ± 10.3 | 0.67 |
| Dipper for SBP (%) | 32.0 (8) | 32.4 (12) | 0.97 |
| Dipper for DBP (%) | 48.0 (12) | 51.4 (19) | 0.80 |
| Antihypertensive drugs | 0.75 | ||
| 3 drugs used [% (n)] | 44 (11) | 51 (19) | |
| 4 drugs used [% (n)] | 36 (9) | 32 (12) | |
| 5 drugs used [% (n)] | 16 (4) | 16 (6) | |
| Good compliance [% (n)] | 72 (18) | 76 (28) | 0.67 |
| Metabolic markers | |||
| Total cholesterol (mmol/L) | 5.17 [4.14; 5.69] | 5.17 [4.40; 5.95] | 0.29 |
| LDL cholesterol (mmol/L) | 2.84 ± 0.76 | 3.10 ± 1.03 | 0.26 |
| HDL cholesterol (mmol/L) | 1.29 [1.03; 1.55] | 1.03 [1.03; 1.29] | 0.06 |
| Triglycerides (mmol/L) | 1.24 [1.02; 1.92] | 1.69 [1.24; 2.37]* | 0.032 |
| Fasting glucose (mmol/L) | 5.2 [4.9; 6.2] | 5.9 [5.4; 7.2]* | 0.018 |
| Insulinemia (μIU/mL) | 10.6 [5.7; 29.0] | 12.1 [8.8; 30.8] | 0.36 |
| HbA1c | 6.0 [5.7; 6.6] | 6.0 [5.7; 7.2] | 0.72 |
| us-CRP (mg/L) | 2.2 [1.0; 4.2] | 2.8 [2.0; 5.4] | 0.16 |
| Leptin (ng/mL) | 17.0 [6.0; 29.0] | 9.0 [6.0; 15.0]* | 0.041 |
| Leptin/weight (ng/mL/kg) | 0.22 [0.07; 0.30] | 0.10 [0.08; 0.19]* | 0.029 |
| Adiponectin (ng/mL) | 7,820 [4,566; 11,718] | 6,393 [4,150; 9,518] | 0.26 |
| Creatinine (μmol/L) | 78 [67; 86] | 90 [82; 104]* | 0.006 |
| MDRD index (mL/min/1.73 m2) | 87 ± 21.6 | 77.6 ± 20.9 | 0.09 |
| SNS markers | |||
| Normetepinephrine (nmol/L) | 10.1 [6.2; 12.3] | 10.0 [8.8; 16.6] | 0.27 |
| Metepinephrine (nmol/L) | 4.0 [2.8; 5.1] | 4.6 [3.5; 5.5] | 0.42 |
| SRA markers | |||
| Aldosterone (ng/L) | 134 [77; 258] | 100 [54; 165] | 0.14 |
| Renin (ng/L) | 11.8 [5.4; 16.0] | 15.3 [6.9; 41.9] | 0.17 |
Data are mean ± SD, median [25th; 75th percentiles] or percentage.
aMetabolic syndrome was defined according to the International Diabetes Federation recommendations (29).
bAmbulatory BP monitoring was mandatory to define RH. Office BP values are provided only for readers information.
*p < 0.05 by Student or Mann–Whitney test. For qualitative data, a Chi-square test or a Fisher test was performed.
HbA1c, glycosylated hemoglobin; AHI, apnea–hypopnea index; BMI, body mass index; BP, blood pressure; DBP, diastolic blood pressure; HDL, high-density lipoprotein; HR, heart rate; LDL, low-density lipoprotein; MABP, mean arterial BP; MDRD, modification of diet in renal disease; MI, myocardial infarction; RAS, renin–angiotensin system; SaO2, oxygen saturation; SaO2 < 90%, percentage of recording time spent at a SaO2 < 90%; SBP, systolic blood pressure; SNS, sympathetic nervous system; TIA, transient ischemic attack; us-CRP, high-sensitivity C-reactive protein.
Bold font indicates the significativity of the results.