Prevalence of renal artery stenosis in subjects with moderate hypertension. A population-based study

Aim. To examine the prevalence of significant renal artery stenosis (RAS) in subjects with moderate to severe hypertension. Materials and methods. Subjects aged 50-66 years with blood pressure > 160/100 mmHg or receiving antihypertensive treatment were selected from the population study Inter99. We examined 332 subjects (209 men, 123 women) for RAS > 50% of diameter with Doppler-US. Subjects with RAS were re-examined 2 years later. Furthermore, we report sensitivity and specificity of the screening method based on consecutive examinations of 100 patients before referral to renal angiography. Results. The sensitivity and specificity of the Doppler US examination for the detection of RAS was 98% and 96%, respectively. Unilateral RAS was found in 11 subjects. Nine were women. The prevalence of RAS in the examined population was 3.3% (men: 0.9%, women: 7.3%). One patient was referred to balloon angioplasty. Two patients had reduced size and function of the affected kidney. Among the non-invasively treated patients, one showed stenosis progression at the 2-year follow-up examination. Conclusion. In subjects aged 50-66 years with hypertension grade II-III, RAS is rare among men, but not among women. These women may suffer from fibromuscular dysplasia. They are at risk of losing kidney function and developing severe hypertension, but they would not have been considered for screening according to present criteria.