Diet monotony as a correlate of poor nutritional intake among hemodialysis patients

Nutritional guidelines recommend eating a variety of foods, yet the renal diet restricts the intake of many foods. Poor appetite, present in 10% to 30% of hemodialysis patients, further narrows the range of foods consumed. We sought to determine the relationship between diet monotony and nutritional intake in patients on chronic hemodialysis.

Cross-sectional study.

Eight freestanding hemodialysis units in northeast Ohio.

Forty-eight randomly selected hemodialysis patients.

We used the Block-National Cancer Institute questionnaire to obtain a detailed food frequency and also asked patients to rate their appetite for 10 specific high-protein foods.

We adapted the Herfindahl index (a measure of hospital market concentration) to calculate a diet monotony index and then examined the relationship between monotony index and energy and protein intake.

When stratified into tertiles by monotony index, patients with the most varied diets had the highest energy (33 kcal/kg/d) and protein (1.35 g/kg/d) intake, whereas patients with the most monotonous diets had the lowest energy (21 kcal/kg/d) and protein (0.83 g/kg/d) intake. A 5-point increase in monotony index was independently associated with a 10 kcal/kg/d decrease in energy intake (P = .004) and a 0.43 g/kg/d decrease in protein intake (P = .006) after adjustment for patient demographic and medical characteristics. Patients with the most monotonous diets reported a good appetite for an average of 3.1 high-protein foods that they were eating less than once per week.

Diet monotony strongly correlates with nutritional intake. However, patients with monotonous diets have a good appetite for several high-protein foods that they are not eating. Helping patients to identify and increase the intake of these foods may both enhance diet variety and improve nutritional status.