201
5
1.0
1.5
2.0
2.5
3.0
3.5
10 15 20 30 40 50
Apnoea-hypopnoea index
Odds ratio
Odds ratios
Wald 95% confidence intervals
60 70
Fig. 13.2 Incidence of hypertension over time in patients without OSA and untreated patients
with OSA of varying severities. Severity of OSA was defined by the apnea-hypopnea index (AHI)
as mild OSA (AHI 5.0–14.9), moderate OSA (AHI 15.0–29.9), and severe OSA (AHI ≥ 30) (From
Lavie et al. [ 14 ]; with permission)
Recurrent episodes of airway obstruction during sleep
Intermittent hypoxia/Sleep fragmentation
Hypercapnia
Chemoreflex activation
autonomic CV modulation
RAAS activity
Aldosterone
Sympathetic
activation
ROS, ET-1,
NOS blockade
Vascular tone hypertensive peak followingsudden recovery
of LV function
OSAs-related
myocardial damage
arterial stiffness, LVH
office BP and 24th, day and night-time ambulatory BP levels
Non dipping pattern of BP, nocturnal hypertension
Fluid retention
NO production
vasodilatation
Inflammation
Oxidative stress
Endothelial
dysfunction
Dysglycemia;insulin
and leptin resistance
Alterations in LV
mechanical properties
changes in pulmonary volume
intrathoracic pressures
Fig. 13.3 Mechanisms by which obstructive sleep apnea syndrome (OSAS) may contribute to
resistant hypertension (From Parati et al. [ 35 ]; with permission)
13 Obstructive Sleep Apnea and Resistant Hypertension