Background: Patients with coronary artery disease (CAD) had significantly lower bile acid excretion (BAE) compared with non-CAD patients, leading to the hypothesis that the inability to efficiently excrete bile acids leads to coronary atherosclerosis development. We investigated the long-term role of BAE in CAD development and related mortality in 50 patients with proven CAD compared with that of 50 patients with chest pain and no CAD (controls) matched for clinical and laboratory characteristics.
Methods: All subjects received a 4-day standard diet that included ~500 mg of cholesterol. Fecal bile acids from 24-h stool collections were measured by gas liquid chromatography.
Results: CAD patients excreted lower amounts of total bile acids than controls (p < 0.001), less deoxycholic acid (p < 0.0001) and less lithocholic acid (p < 0.01). BAE was the best significant independent laboratory factor that predicted CAD (p < 0.05). Mortality and CAD development rates were significantly lower for the controls at the 20-year follow up.
Conclusions: These results showed that CAD patients had markedly decreased BAE levels compared with non-CAD controls. BAE <415 mg/day was associated with increased CAD long-term mortality. Impaired ability to excrete cholesterol might be considered an additional independent risk factor for CAD development.
Keywords: atherosclerosis; bile acids; coronary artery disease; high-density lipoprotein; low-density lipoprotein.