Ivan Barišić

Platelet serotonin concentration in dialysis patients with somatic symptoms of depression.

Platelet serotonin (5-HT) concentration was measured in 65 male and 45 female chronic renal patients on hemodialysis (HD) with different somatic symptoms of depression (crying spells, irritability, sleep disturbance, fatigability, loss of appetite, weight loss, somatic preoccupation and loss of libido), to find out the relationship between the severity of symptoms and platelet 5-HT concentration. Male and female patients had significantly lower platelet 5-HT concentration than 62 male and 38 female healthy subjects. Gender-differences in platelet 5-HT values observed in healthy subjects were not found in patients. Platelet 5-HT concentration differed in the groups of patients with the different scores of particular somatic symptoms (loss of appetite and loss of libido), but was similar in patients with other somatic symptoms. There was no relationship between platelet 5-HT concentration and the severity of somatic symptoms, or between platelet 5-HT concentration and age of the patients. Gender-related differences in the occurrence of somatic symptoms were detected in patients with the different degrees of weight loss, somatic preoccupation and loss of libido. Our results suggest that platelet 5-HT concentration could not be used as a biological marker for the severity of somatic symptoms in chronic renal patients on HD.

Lack of association between brain-derived neurotrophic factor Val66Met polymorphism and body mass index change over time in healthy adults.

Obesity is becoming the epidemic health problem worldwide with a very complex etiology. The interaction between diverse genetic and environmental factors contributes to development of obesity. Among myriad of functions in central and peripheral tissues, brain-derived neurotrophic factor (BDNF) also regulates energy homeostasis, food intake and feeding behavior, and has a role in obesity and increased body mass index (BMI). BDNF Val66Met (rs6265) polymorphism is associated with BMI gain, but both positive associations and non-replications are reported. Since BMI changes over time and since genetic influences on BMI vary with age, the aim of the study was to evaluate association between BDNF Val66Met polymorphism and BMI gain in healthy subjects with middle or old age. The study included a cohort of 339 adult healthy Caucasians of Croatian origin, free of eating and metabolic disorders, evaluated in three time periods in the year 1972, 1982 and 2006, when the subjects were around 40, 50 and 70 years old, respectively. The results revealed a significant effect of smoking on BMI, but a lack of significant association between BDNF Val66Met polymorphism and overweight or obesity, and no significant association between BDNF Val66Met and BMI changes over time. These results did not confirm the major role of BDNF Val66Met in the regulation of BMI changes in adult and old healthy subjects.

Comorbid depression and platelet serotonin in hemodialysis patients.

Background/Aim: Comorbid depression often occurs in chronic renal failure patients on hemodialysis (HD). Reduced serotonin (5-HT) function is implicated in the pathophysiology of depression. Methods: Comorbid depression and different clusters of depressive symptoms were assessed in 79 male HD patients and 35 male depressed psychiatric patients. Platelet 5-HT concentration (a peripheral model for the central serotonergic neurons) was determined in all patients and 80 male healthy controls. Results: Comorbid depression occurred in 50 out of 79 HD patients. Depressed psychiatric patients and depressed HD patients had higher scores of anxiety, retardation, and cognitive symptoms than nondepressed HD patients. Platelet 5-HT concentration was lower in depressed or nondepressed HD patients than in healthy controls, or in depressed patients. Higher platelet 5-HT content was found in depressed psychiatric patients with depressive clusters than in all other patients. Among HD patients, anxious HD patients had a higher platelet 5-HT concentration than HD patients without anxiety symptoms. Conclusions: Comorbid depression occurred in 63% of HD patients. Dialyzed patients had decreased platelet 5-HT concentration, regardless of the occurrence of comorbid depression. Higher platelet 5-HT concentration was related to anxiety symptoms in HD patients. Our data suggest that platelet 5-HT concentration might be a suitable marker for anxiety symptoms in dialyzed patients.

[PP.28.05] CHARACTERISTICS OF BLOOD PRESSURE IN PATIENTS UNDERGOING CHRONIC HEMODIALYISIS

Objective: Cardiovascular (CV) disease is the most important cause of morbidity and mortality among patients with chronic kidney disease particularly in those undergoing chronic hemodialysis (HD). Hypertension (HT), the most important CV risk factor is frequently present and has several particular characteristics. Our aim was to analyze characteristics of HT in our group 194 patients undergoing HD. Design and method: In this study we have analyzed characteristics of HT and arterial stiffness (i.e. PWV) in 194 patients (118 m, 83 w; mean age 63+/-15 y). All patients were dialyzed three times a week with standard bicarbonate hemodialysis solutions and synthetic dialyzers according to the recent international guidelines. All measurements were done mid week day. Blood pressure (BP) was measured with Omron M6 (after dialysis session), ABPM using Spacelab 90207 (24 h) and PWV (before dialysis session) was determined with Arteriograph. Results: Significant difference in BP values measured after dialysis and ABPM were found (day, night, for both systolic and diastolic BP). Only 6.6% patients were normotensive, 63.3% hypertensive, while white coat (WCH) and masked hypertension (MH) were diagnosed in 26.4% and 3.7%, respectively (no gender differences). There were no differences in BP values between men and women, but PWV > 10m/s were found more frequently in men than in women in (m vs. w 56.5% vs.39.7%;p = 0.049; 48.3% in total; 10.4 +/-1.9 vs.9.7+/-1.7;p < 0.01). In logistic regression age was the most important predictor for pathologic values of PWV. WCH had slightly higher values of PWV than normotensives (9.7 +/-2.0 vs.8.5+/-1.3; p = 0.09). PWV in MH was not different compared to the sustained HT (10.2+/-1.7). Non-dipping status was established in 45.3%, extreme dipping in 18.8%, and only 21.6% were dippers. Conclusions: Our results confirmed significant clinical value of ABPM in patients undergoing dialysis. Determination of WCH subjects and non-dippers is of utmost importance for everyday tailoring of therapy. Increased arterial stiffness should be considered as well.