Renin-angiotensin-aldosterone System Polymorphisms in Resistant Hypertension and Adverse Cardiovascular Events

Observational Study of the Polymorphisms of the Renin-angiotensin-aldosterone System and Their Relation to Resistant Systemic Arterial Hypertension and Adverse Cardiovascular Events

Renin-angiotensin-aldosterone system (RAAS) polymorphisms influence 24h arterial pressure fluctuation. Resistant systemic arterial hypertension (RSAH) has an increased risk of end organ damage and unfavourable prognosis, whereas pseudo-RSAH usually respond favourably to drug therapy.

To prospectively investigate, in subjects with RSAH in a tropical South American city: 1) Adverse cardiovascular events defined as fatal and non-fatal stroke or acute myocardial infarction (AMI); and 2) the association of RAAS polymorphisms and adverse cardiovascular events in this population.

Study population: 212 hypertensives recruited from primary care assistance (time since first diagnosis of hypertension: 16.5±8.1 years) and without appropriate pressure control, between 2001 and 2006, corresponding to 0.48% of all hypertensives under care (18 new cases/year), 57±10 years old, 66% females. Under drug treatment schedule: three or more drugs including a diuretic. Ninety two randomly selected hypertensives basis had renin-angiotensin-aldosterone system genetic profile determined. Genetic assessment was carried out using a polymerase chain reaction assay amplification technique. The following single nucleotide polymorphisms were analyzed: renin (G1051A), angiotensinogen (M235T), angiotensin converting enzyme-ACE (I/D), angiotensin II type 1 receptor (A1166C), aldosterone synthase (C344T) and mineralocorticoid receptor (G3514C).

Inclusion Criteria:

• Subjects with uncontrolled systemic arterial hypertension despite use of three anti-hypertensive drugs, including one diuretic

Exclusion Criteria:

• Secondary causes of systemic arterial hypertension