Hyperleptinemia is not responsible for decreased paraoxonase activity in hemodialysis patients.

BACKGROUND: Exogenous leptin markedly decreased plasma paraoxonase (PON1) activity in rats. Hyperleptinemia and decreased PON1 activity have previously been demonstrated in uremia. Therefore, we investigated the relationship between leptin level and PON1 activity in hemodialysis (HD) patients. METHODS: Leptin and PON1 were determined in 40 HD patients and 40 age-matched controls with similar body mass index (BMI). RESULTS: Leptin was higher (p < 0.001) and PON1 activity was lower (p < 0.001) in HD patients than in controls. PON1 and PON1/HDL ratio was higher in HD patients with BMI >25 kg/m2 than in HD patients with BMI <25 kg/m2. It was not due to a difference in frequency of high activity phenotype of PON1 among subgroups of HD patients. There was no similar difference in controls. Spearman analysis showed a significant correlation between leptin and PON1 activity (p < 0.02), BMI (p < 0.001), triglyceride (TG) (p < 0.03), and Kt/V (-0.323, p < 0.03), but multiparametric regression analysis did not reveal it. PON1 activity depended on BMI in both models. In controls, leptin correlated with BMI (p < 0.001) and TG (p < 0.002) but not PON1 activity. A slight decrease in leptin concentration and PON1 activity during HD was observed. CONCLUSION: Our results suggest the role of other pathophysiological conditions besides hyperleptinemia resulting in decreased PON1 activity in HD patients.

Dietary self-efficacy: determinant of compliance behaviours and biochemical outcomes in haemodialysis patients.

BACKGROUND: Despite the diversity of proposed theories, researchers are still unable to fully explain dietary compliance behaviours of dialysis patients. Dietary self-efficacy, a concept less studied in dialysis, has been linked to positive compliance outcomes in the chronic illness literature. Therefore, the aim of the present research was to determine how dietary self-efficacy is related to selected biochemical markers and self-reported behavioural outcomes in haemodialysis patients. METHODS: 107 subjects participated in a cross-sectional study. Four questionnaires assessed dietary self-efficacy, compliance attitudes and behaviours, and staff-patient relationships. Laboratory outcomes were retrospectively obtained from patients' medical records and averaged for the previous 6 months. RESULTS: Of the behavioural measures, only dietary self-efficacy was associated with laboratory outcomes. Dietary self-efficacy was also positively related to staff-patient relationships and to patients' self-reported assessment of compliance behaviours. Women had greater dietary self-efficacy than men. The number of family members living with the respondent was inversely related to dietary self-efficacy. CONCLUSIONS: Results indicated that dietary self-efficacy determined both behaviours and laboratory outcomes. Patients with greater dietary self-efficacy had lower serum potassium and weight gain, showed favourable compliance attitudes and behaviours toward prescribed regimens and fostered better relationships with staff. Based on these findings we recommend an experimental approach to clarify whether maximizing dietary self-efficacy efforts is without psychological burden to patients and whether the positive effect of increased dietary self-efficacy is maintained in long-term dialysis patients.

Increased common carotid artery intima media thickness in adolescent hypertension: results from the Debrecen Hypertension study.

BACKGROUND: The aim of the present work was to investigate intima media thickness (IMT) in healthy and in hypertensive adolescents and its influencing factors. METHODS: 103 hypertensive and 58 healthy adolescents were studied. IMT was measured in the common carotid artery using B-mode ultrasonography. Additionally, laboratory parameters (blood glucose, cholesterol, triglycerides, HDL- and LDL-cholesterols) and left ventricular mass indices were obtained. RESULTS: IMT in the common carotid artery was higher in hypertensive adolescents (means +/- SD: 0.55 +/- 0.11 mm) than in healthy control subjects (0.48 +/- 0.08 mm, p < 0.001). Similarly, a higher left ventricular mass index was measured in hypertensive (103.2 +/- 30.6 g/m(2)) than in healthy teenagers (91.1 +/- 25.2 g/m(2), p < 0.001). In general, IMT in adolescents was associated with age, weight, body mass index, left ventricular mass index and average systolic and diastolic blood pressure values of the subjects. By assessing the multivariate association between IMT and other factors, intima-media thickness was only associated with age and left ventricular mass index of the hypertensive subjects and was independent from all the investigated factors in normotensive controls. CONCLUSIONS: Our data suggest an ongoing target-organ damage in adolescent hypertension. These patients need to be subjected to early diagnostic methods, treatment and a regular follow-up, in order to avoid severe clinical manifestations of secondary target-organ damage due to hypertension.

Blood pressure distribution in a Hungarian adolescent population: comparison with normal values in the USA.

OBJECTIVES: To describe the blood pressure characteristics and distribution of all adolescent high school students (aged 15-18 years) in Debrecen (total population 230 000), Hungary. To define threshold values for normal blood pressure by age-, sex- and height-specific groups. To compare our data with results from a USA meta-analysis, which forms the basis of current guidelines. PARTICIPANTS AND METHODS: All young people attending high school in Debrecen (final sample = 10 359) participated in the study. After they had rested for 10 min, three blood pressure measurements were taken from the right upper arm, separated by 5 min intervals. All measurements were obtained by a validated, automated, digital Omron M4 device. RESULTS: The 50th, 90th and 95th percentile values of blood pressure were defined by dividing the adolescent population into age-, sex- and height-specific subgroups. In comparison with USA guidelines, in our sample the systolic blood pressure of boys in the different subgroups was 6-11 mmHg greater, whereas this difference was less marked for girls (1-5 mmHg). There were no marked differences in diastolic blood pressure, but our values were slightly lower. CONCLUSIONS: Our findings demonstrate the influence of geographical and ethnic variations on blood pressure. Acceptance and use of non-population-specific blood pressure distributions may lead to under- or overdiagnosis of adolescent hypertension. The use of geographically more relevant data should be encouraged.

[Frequency of hyperhomocysteinemia in hemodialysis patients with folic acid supplementation]. / A hyperhomocysteinaemia gyakorisága, folsavpótlásban részesüló hemodializált betegekben.

BACKGROUND: It is known that hyperhomocystinemia is an independent risk factor for development of atherosclerosis. In end stage renal disease the frequency of hyperhomocystinemia is much greater than in normal populations. AIM: In this study homocystein (Hcy), folic acid and vitamin B12 concentrations were determined in 125 chronic renal failure patients being on folic acid supplementation (3 mg/day). In 107 patients the frequency of C667T polymorphism of methylene tetrahyrofolate reductase (MTHFR) was also determined. The relationships between these parameters were also studied. RESULTS: It was found that in these patients who are under continuous folic acid supplementation the mean level of homocysteine was 16.8 +/- 7.2 mumol/L, a value considerably lower than the homocysteine concentration reported for non-supplemented patients. The elevation of homocysteine concentrations was independent of gender, time spent in renal replacement therapy, and the type of renal replacement therapy (hemodialysis: 17.6 +/- 12.6; hemodiafiltration: 16.6 +/- 12.9 mumol/L). Data showed an inverse relation between plasma homocysteine concentrations and the concentrations of folic acid and vitamin B12. Moderately severe hyperhomocystinemia (Hcy > 20 mumol/L) was found in about 30% of patients. In those the frequency of patients for homozygous T677 allele of MTHFR was about 25-30%. However, in all ESRD patients the frequency of the homozygotes was the same then in the normal population. Homocysteine plasma levels correlated with MTHFR polymorphism: in the wild type group Hcy was 14 +/- 7 mumol/L, in the heterozygous group was 17.2 +/- 6.2 mumol/L, and in the homozygous group was 21 +/- 19 mumol/L. CONCLUSIONS: Long-term folic acid supplementation decreased the homocysteine level in end stage renal disease patients. However, in folic acid resistant group, who were in 30% homozygotes for C667T of MTHFR (suggesting that homocysteine-methionine remethylation cycle is disturbed), instead of the administration of folic acid, methylene tetrahydrofolate supplementation might be considered.

Effects of haemodialysis on maximum P wave duration and P wave dispersion.

BACKGROUND: Analysing a 12-lead surface electrocardiogram (ECG), the inter-lead variability of the P wave interval, i.e. P wave dispersion, is defined as the difference between the maximum and the minimum P wave duration. Our aim was to assess the effect of haemodialysis on P wave duration and dispersion in non-diabetic patients with end-stage renal failure on chronic haemodialysis. METHODS: Twenty-eight patients (14 men and 14 women, mean age 58+/-16 years, average duration of dialysis 4.5+/-2.8 years) were examined. Prior to haemodialysis, echocardiography (M-mode and two-dimensional) was performed. Haemodialysis sessions were carried out with polysulfone dialysers and bicarbonate dialysate fluids. Twelve-lead ECGs were recorded at the beginning, 15 and 30 min after starting dialysis, at the end, and 2 h after completion of each session. Ionic parameters were checked during the study. P wave durations were measured with calipers in three consecutive complexes of each lead by one observer. RESULTS: P maximum was 58+/-16 ms at the beginning, and showed an increase by the end of dialysis to 98+/-8.9 ms (P<0.0001). Pre-dialysis P dispersion was 23+/-10 ms and increased to 41+/-16 ms by the end of the sessions (P<0.0001). In patients with a left atrial diameter larger than 45 mm, P dispersion increased from 23+/-11 to 53+/-10 ms (P<0.0003) by the end of the sessions. CONCLUSIONS: According to our results, ionic imbalance and dialysis itself may cause changes in P duration and dispersion simultaneously.

[Acute toxicological cases during a ten-year period in our clinic]. / Akut toxikológiai eseteink klinikánk tízéves beteganyagában.

INTRODUCTION: There's a fact, that Hungary has held the first places in suicidal statstics. METHODS: The authors studied toxicological cases between 1989 and 1998 at the 1st Department of Medicine of the Medical and Health Science Centre, at the University of Debrecen, paying special attention to suicidal poisoning cases. RESULTS: 2% of the patient turnover accounted for acute poisoning cases, the number of which increased during the 10 years in question. 70% of the cases were of suicidal intentions, 20% were unintentional, these poisonings were not committed on purpose, while the proportion of iatrogenic intoxication cases was 10%. Amongst the failed suicide cases there was a higher proportion of women, whereas a higher percentage of men accounted for "successful" suicide cases. When examining auto-intoxication cases it turned out that the medicine most frequently used was meprobamate, besides benzodiazepines. Mortality rate was highest in the glutethimide intoxication cases. Most poisonings with suicidal intentions took place in the 2nd quarter of the year. Most completed suicides were committed on Wednesdays and Thursdays. 81% of the iatrogenic intoxication cases happened to be with digitalis and coumarin overdose. Nearly 50% of the cases turned out to be combined intoxications. 40% of the men took alcoholic drinks during the auto-intoxications. In the case of 135 patients extracorporeal detoxification therapy was applied, which consisted mostly of hemoperfusion. Three quarters of the patients needed psychiatric care and every fourth patient was admitted to the Department of Psychiatry. 6.9% of the poisonings were fatal. CONCLUSIONS: The growing number of toxicological cases--amongst these suicidal poisonings--compels us to pay more attention to the setting up of interdisciplinary based prevention as well as running effective toxicological centres. All physicians have a responsibility to recommend psychiatric care for people suffering from mental problems or depression and for the unsuccessful or potential suicide seeking help for the first time. Family doctors in primary medical care and who meet patients first have an important role in this job.