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

Objective: 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.

Design: Cross-sectional study.

Setting: Eight freestanding hemodialysis units in northeast Ohio.

Subjects: Forty-eight randomly selected hemodialysis patients.

Intervention: 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.

Outcome Measure: 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.

Results: 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.

Conclusion: 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.