ARTERIAL HYPERTENSION DOES NOT SLEEP

Abstract

Objective: Sleep apnea is a secondary cause of hypertension and is suggested by non-dipper profile at ambulatory blood pressure monitoring (ABPM). The prevalence is estimated between 30-50% in hypertensive patients. Design and method: A 60 year-old man with cardiovascular risk factors (hypertension, diabetes, dislipidemia, obesity, transient ischemic attack) presented to the outpatient clinic with high values of self-monitoring blood pressure despide multiple lowering blood pressure therapy. On physical examination his body mass index was 39.6 kg/m2, neck circumference 50 cm. The ECG was in sinus rhythm with hypertrophic phenotype confirmed by echocardiogram, which also showed left ventricle preserved ejection fraction, grade III diastolic dysfunction, mildly enlarged left atrium. Laboratory tests exluded endocrinologic and renal causes. Despite lifestyle changes and a good adherence to multiple associated antihypertensive treatment, ABPM revealed a non-dipper profile (dipping index 4.86%) (figure 1). The patient underwent the polygraphy test which showed the apnea-hypopnea index (AHI) of 10.6, which led to a diagnosis of mild sleep apnea, the t90% of 57 pointed out severe hypoxia and high pulse variances 104 (figure 1). The further Holter monitoring revealed episodes of atrial flutter and atrial fibrillation. Results: After 3 months of continuous positive airways pressure (CPAP) therapy, on top of the same antihypertensive drugs and anticoagulation, led to optimal blood pressure values and normal ABPM profile (figure 2). The polygraphy parameters AHI, t90% and pulse variances normalised too. (figure 1) Conclusions: Obstructive sleep apnea is a prevalent secondary cause of hypertension and atrial arythmias, still greatly underdiagnosed. It is associated with abdominal obesity, large neck, snoring, daytime fatigue and a decrease in the quality of life. Polygraphy is a feasible method for diagnose sleep apnea and monitoring the treatment. CPAP treatment abolishes apnea, normalises blood oxigenation thereby prevents arterial pressure surges, restoring the nocturnal ‘dipping’ pattern and normal sinus rythm.