BLOOD PRESSURE AND BAROREFLEX SENSITIVITY AFTER ANTHRACYCLINE CHEMOTHERAPY IN CHILDHOOD WITH RESPECT TO FATTY ACID METABOLISM

A b s t r a c t Late effects of cardiotoxic therapy on childhood cancer were studied. Body and circulation param-eters were compared in 206 healthy controls (C), and 97 children and adolescents after antitumour treatment (T) at the age of 11–21 years with respect to plasma lipid level. We recorded inter-beat intervals (IBI), systolic (SBP) and diastolic (DBP) blood pressures beat-to-beat for 5 min (Finapres). Baroreflex sensitivity (BRS) was determined by the spectral method. Variability of circulatory param-eters was estimated as standard deviations: IBI (IBIsd), SBP (SBPsd), and DBP (DBPsd). Plasma lipids (cholesterol, HDL, LDL, and triglycerides) were examined. Subjects T were divided according to the level of cholesterol into two subgroups: 84 subjects (subgroup TL) with cholesterol lower than 5 mmol/l and 13 subjects (subgroup TH) with cholesterol higher than 5 mmol/l. In groups T vs. C, the subjects had significantly higher BMI (p<0.01), but they were not obese, they had longer IBI (p<0.01), increased IBIsd (p<0.05), decreased SBP (p<0.01), DBP (p<0.01) and DBPsd (p<0.05), and lower BRS (p<0.01). The only difference between subjects TH and TL was a more prolonged IBI in TL than in TH (p<0.05). The subjects after antitumour therapy had increased parasympathetic and decreased sympathetic tonic activity together with decreased baroreflex sensitivity. The increase of IBI variability was neither the result of a primary increase of vasomotor activity nor an increase of BRS response to changes in blood pressure. We can explain it by increasing parasympathetic control of the heart. The circulatory changes did not bear on obesity, but they were rather a specific effect of tumour disease and antitu-mour treatment. K e y w o r d