Physical activity, high-density lipoprotein cholesterol subfractions and lecithin:cholesterol acyltransferase in dialysis patients.

BACKGROUND/AIMS: Although a low level of high-density lipoprotein cholesterol (HDL-C) is an independent risk factor for atherosclerotic heart disease, the mechanism of HDL-C abnormality in hemodialysis (HD) as well as peritoneal dialysis (PD) patients is not fully understood. The purpose of this study was to investigate the relationship of physical activity with HDL-C subfractions and lecithin:cholesterol acyltransferase activity in HD and PD patients. METHODS: Thirty-five HD and 26 PD patients were studied. Physical activity was estimated as the average number of steps taken per day over 7 days (steps/day). RESULTS: When possible confounding factors were included in the stepwise multiple regression analyses, in HD patients, steps/day was significantly positively related to HDL(2)-C and apolipoprotein (Apo) A-I, while it was significantly positively related to HDL(3)-C in PD patients. When subjects were subdivided into 3 groups according to steps/day, in HD patients, the highest category of steps/day had significantly higher HDL(2)-C and Apo A-I than the lowest category, while such results were not observed in PD patients. CONCLUSION: These results suggest that the associations of physical activity with HDL-C subfractions and Apo A-I that are known in the general population are more pronounced in HD patients than PD patients.

Physical activity and blood lipids and lipoproteins in dialysis patients.

The relationship between physical activity and blood lipids and lipoproteins in dialysis patients is reviewed in the context of the potentially confounding factors such as nutritional intake, cigarette smoking, obesity, alcohol intake, and physical activity levels in the general population and additional confounding factors such as mode of dialysis and diabetes in dialysis patients. The known associations in the general population of physical activity with high-density-lipoprotein cholesterol subfractions and apolipoprotein A-I are more pronounced in hemodialysis patients than in peritoneal dialysis patients even after adjusting for these confounding factors. Examining studies on the effects of physical activity on blood lipids and lipoproteins, the most consistent observation is the noted decrease in triglycerides and increase in high-density-lipoprotein cholesterol and insulin sensitivity in hemodialysis patients. The changes in lipids and lipoproteins in hemodialysis patients could be caused by changes in activity levels of lipoprotein lipase, insulin sensitivity, and/or glucose metabolism. Future research investigating the relationship between physical activity and blood lipids and lipoproteins in dialysis patients should direct research towards the underlying mechanisms for changes in blood lipids and lipoproteins.