Background: Kidney failure is believed to have a negative impact on cognitive function, and cognitive impairment is common among maintenance hemodialysis (HD) patients. Previous studies have shown a beneficial effect of kidney transplantation in certain cognitive tests but not across all cognitive domains assessed. But, most of these studies performed a cross-sectional analysis, suffered from lack of standardization of adequate dialysis dose, hemoglobin level, and insufficient sensitivity of neuropsychological tests. The aim of this study was to evaluate the effect of successful kidney transplantation on cognitive and psychomotor function in adequately dialyzed HD patients without severe anemia, using sensitive neuropsychological tests. Methods: Twenty-one medically stable patients (aged 45.1 ± 7.9 years) on maintenance HD (7.6 ± 4.2 years) were investigated before and 20.5 ± 8.5 months after successful kidney transplantation using Complex Reactiometer Drenovac, a battery of computer-generated psychological tests which measure a simple visual discrimination of signal location, short-term memory, simple convergent visual orientation and convergent thinking. Results: Our findings indicated significantly better cognitive and psychomotor performance after transplantation on tests that assess processing speed, attention, short time memory, convergent thinking and executive functioning. Also, significant negative correlation between follow-up time after transplantation and cognitive and psychomotor performance in minimum time of solving test of convergent thinking was found. Conclusion: We conclude that cognitive and psychomotor functions are superior after successful kidney transplantation compared with HD, and that early beneficial effects of transplantation are not transient and cognitive and psychomotor performance might be even improved in time following successful transplantation.

Objective: Change in cognitive function is one of the well-known consequences of the end-stage renal disease (ESRD). The aim of this study was to determine the effect of hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) on cognitive and motor functions. Methods: In this cross-sectional study, cognitive and motor functions were investigated in a selected population of 42 patients with ESRD (22 patients on chronic HD and 20 patients on CAPD, aged 50.31 ± 11.07 years). Assessment of cognitive and motor functions was performed by Symbol Digit Modalities Test (SDMT) and Complex Reactiometer Drenovac (CRD-series), a battery of computer-generated psychological tests to measure simple visual discrimination of signal location, short-term memory, simple convergent visual orientation, and convergent thinking. Results: The statistically significant difference in cognitive-motor functions between HD and CAPD patients was not found in any of the time-related parameters in all CRD-series tests or SDMT score. Higher serum levels of albumin, creatinine, and calcium were correlated with better cognitive-motor performance among all patients regardless of dialysis modality. The significant correlation between ultrafiltration rate per HD and short-term memory actualization test score (CRD-324 MT) among HD patients was found (r = 0.434, p = 0.025). Conclusion:This study has demonstrated that well-nourished and medically stable HD and CAPD patients without clinical signs of dementia or cognitive impairment and without significant difference in age and level of education performed all tests of cognitive-motor abilities without statistically significant difference.

Background: As patients on chronic haemodialysis (PCHD) elicit a weaker response to vaccination with recombinant hepatitis B virus surface antigen (HBsAg), we conducted this study to see how dialysis efficacy affects response to hepatitis B virus (HBV) vaccination. Methods: Study subjects consisted of 30 PCHD. All subjects were vaccinated with 4 × 40 µg HBsAg i.m. at 0, 1, 2, and 6 months. If a subject had an HBsAg antibody (HBsAb) level <10 IU/l after vaccination, he or she received a booster dose. Subjects were divided into groups according to the level of HBsAb: non-responders (<10 IU/l), weak responders (10–100 IU/l), and good responders (>100 IU/l). Results: The group of responders had a significantly more efficient dialysis (Kt/V) than the group of non-responders (p = 0.027). This difference was not observed between groups of non-responders and weak responders. The group of good responders had a significantly better Kt/V than the group of non-responders (p = 0.012). Good responders had a significantly better Kt/V than weak responders (p = 0.019). Kt/V values showed a significantly positive correlation with the HBsAb level (r = 0.47; p = 0.006). Conclusions: The HBV vaccination reaction was weaker in PCHD with inefficient dialysis. Efficient haemodialysis significantly improves the response to vaccination with recombinant HBsAg.

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.