Relationship between serum leptin level and laboratory and anthropometric indices of malnutrition in patients on hemodialysis

Protein-energy malnutrition is a major problem and one of the risk factors for mortality in hemodialysis patients. There is no single index in evaluation of nutritional status in these patients, so leptin can be used as one of the parameters. In this study, the correlation between serum leptin with biochemical and anthropometric parameters of nutrition has been evaluated. This cross-sectional study has been performed on 60 hemodialysis patients (32 males and 28 females) in 2006. The patients on hemodialysis for under 1 year and who has a history of consumption of lipid lowering agents or glucocorticoids, or an infectious or inflammatory disease were excluded. Malnutrition laboratory parameters and serum leptin were measured before hemodialysis. Serum leptin was measured with enzyme-linked immunosorbent assay (ELISA) method with direct dbc kit and malnutrition laboratory parameters measured with standard laboratory methods, patients anthropometric parameters evaluated after hemodialysis. The mean age of patients was 47.5 ± 16.1 years and the range of serum leptin level was 0.6-64.8 ng/ml. Mean serum leptin level were 22.64 ± 19.54 ng/ml in females and 16.74 ± 20.16 ng/ml in males on hemodialysis and in spite of higher level of leptin in females there was not any statistically significant difference between females and males serum leptin. Absolute value of correlation coefficient between serum leptin and anthropometric parameters and most laboratory parameters was < 0.25 (except ferritin, iron, phosphorous in males and total protein, hemoglobin, urea, and creatinin in females which was between 0.25 and 0.50). Our results suggest that the increased serum leptin level does not have a major role in diagnosis of malnutrition in hemodialysis patients and there is a poor correlation between malnutrition parameters and serum leptin level.