Prevalence and severity of atherosclerosis in renal artery in Northwest Indian population: an autopsy study

Background  Atherosclerosis has been described as the most common cause of renal artery stenosis. The purpose of this autopsy study was to assess the preponderance and severity of atherosclerotic changes in renal artery in different age groups in normal population. Methods  Ninety renal arteries from 45 cadavers above 30 years of age were obtained at autopsy. Fifty-four renal arteries were studied grossly after Sudan IV staining for extent and severity of fatty deposits in terms of Atherosclerotic index (AI). Another 36 renal arteries were studied microscopically for changes in different layers and at different sites of artery and luminal narrowing, if any with advancing age. Results  In grossly stained specimens, incidence and AI which is the marker of extent and severity of lesions were found to increase gradually with advancement of age. Increased incidence of atherosclerotic changes with better nutritional status was recorded. In microscopically studied specimens, intimal thickness which is a marker of disease also showed upward rise with advancing age. Renal artery stenosis was prevalent in 13.8% cases. Lesions were most commonly detected at renal ostium and proximal segment. Conclusions  Fatty changes appear with advancing age. Advanced types of changes including fibrous plaques, calcification and ulceration were noticed first in fifth decade. The changes were usually bilateral. Proximal segment was the most affected part. Four cases had less than 50% and one case had 70% luminal narrowing. The changes were only moderately severe in most of the cases.