Effects of nutritional parameters on nocturnal blood pressure in patients undergoing hemodialysis

Malnutrition is a common problem in uremic patients. It is unclear whether there is an association between the degree of malnutrition and 24-h ambulatory blood pressure patterns in patients undergoing hemodialysis. In the present study, we observed the relationship between the degree of malnutrition and deterioration of the rhythm of diurnal blood pressure, which are both risk factors for cardiovascular morbidity-mortality and associated with hypervolemia.

We observed 148 patients undergoing hemodialysis in the Nephrology Department of Celal Bayar University Hospital. All cases were assessed for body weight alterations, dietary food intake, gastrointestinal symptoms, loss of subcutaneous fat and muscle tissue, presence and severity of comorbidities, functional capacity (subjective global assessment), and anthropometric indices. Ambulatory blood pressure measurements were performed for all cases on the day between the two hemodialysis sessions.

We found that the circadian blood pressure rhythm deteriorated in patients with a high-malnutrition score, and that malnutrition was more common and severe in those subjects with the non-dipper and reverse-dipper blood pressure patterns. Malnutrition score was positively correlated with the nighttime systolic and nighttime mean blood pressures and mean 24-h arterial blood pressure (all p ≤ 0.01). We identified a positive correlation between malnutrition score and the reduction in serum albumin and anthropometric indices.

This is the first study to demonstrate an association between malnutrition and deterioration in the circadian blood pressure rhythm in a hemodialysis population. Nutritional disturbance is associated with an increase in night-time blood pressure. Low serum albumin levels and hypervolemia may contribute this situation.