Association of leptin with hemodialysis-related muscle cramps: a cross-sectional study.

BACKGROUND/AIMS: The mechanism of muscle cramp in hemodialysis patients is not well understood. Leptin, a middle molecule uremic toxin, is able to affect neuronal activity. This study aimed to determine the association between leptin and hemodialysis-related muscle cramps. METHODS: A total of 79 hemodialysis patients were enrolled. The episodes of hemodialysis-related muscle cramps were recorded over a 28-day period. Serum levels of leptin were measured on the 15th day, a mid-week dialysis session. RESULTS: Frequent hemodialysis-related cramps were associated with old age and elevated serum leptin levels. The risk of frequent hemodialysis-related cramps increased with increasing tertiles of leptin concentration. This relationship remained significant after adjustment for age, mean ultrafiltration ratio, gender, body mass index, insulin, resistin, c-reactive protein, albumin, peripheral arterial disease, electrolytes, and beta(2)-microglobulin. CONCLUSION: Leptin levels are associated with frequent hemodialysis-related cramps. Further studies are necessary to elucidate the underlying mechanisms.

Nutritional and inflammatory markers in the prediction of mortality in Chinese hemodialysis patients.

BACKGROUND/AIMS: The prevalence of cardiovascular disease and mortality rate is relatively low in Chinese dialysis patients. This study aimed to evaluate the predictive value of nutritional and inflammatory markers in Chinese hemodialysis patients. METHODS: A total of 158 patients (70 men and 88 women, age 59.9 +/- 13.2 years) were studied. Nutritional and inflammatory markers, including subjective global assessment (SGA), insulin-like growth factor-1, albumin, tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-6, serum amyloid A (SAA), and C-reactive protein (CRP), were measured. These patients were followed up until April 2004 (36 months) to determine the incidence and causes of death. RESULTS: SGA (p = 0.001), IL-1beta (p = 0.032), SAA (p = 0.031), IL-6 (p = 0.001) and CRP (p < 0.001) were found to be significant predictors of mortality. After adjusting with age, sex, diabetes, coronary artery disease, Kt/Vurea, and duration on dialysis, CRP (odds ratio = 4.58; p = 0.038) and SGA (odds ratio = 6.57; p = 0.004) remained the independent predictors of mortality. The adjusted mortality rate was highest for patients with a high CRP level and malnutrition (assessed by SGA). CONCLUSIONS: SGA and CRP levels are the most significant predictors of mortality in Chinese dialysis patients. Chinese dialysis patients with a high CRP level tend to be at higher risk of mortality only if they are malnourished.