Seasonal Variations of Nutritional Status in Maintenance Hemodialysis Patients.

Nutritional status of hemodialysis (HD) patients is influenced by a multitude of factors and it strongly correlates with morbidity and mortality. The aim of this study was to investigate the influence of seasonal changes on nutritional status in maintenance HD patients. A selected population of 84 adult (40 females and 44 males, aged 68.98 ± 13.45 years) HD (5.94 ± 6.44 years) patients were investigated. Clinical, biochemical and nutritional parameters (BMI, creatinine, urea, serum albumin, total cholesterol and Dialysis Malnutrition Score (DMS) were measured in cold (January and December) and mild (June and September) months, altogether in 336 HD sessions. Statistically significant differences between cold and mild months were found in BMI (P = 0.046), creatinine before HD (P = 0.011), urea before HD (P ≤ 0.001), urea after HD (P ≤ 0.001) and glucose (P =  0.001). Differences between male and female patients in DMS, serum albumin and creatinine level in cold and mild months were found; where females altogether had higher DMS score and lower serum albumin and creatinine levels. These results suggest that seasonal variations of clinical and laboratory variables that reflect nutritional status occur commonly among maintenance HD patients and might lead to biases in the interpretation of results in clinical studies in which measurement schedules vary during the year. Also, results suggested that female HD patients may constitute an especially vulnerable population for seasonal oscillations of nutritional status. The reasons for most of these variations are not apparent and require further investigation.