[Heart rhythm reactivity in patients with endogenous depression. I. Respiratory tests]

The aim of the study was the evaluation of central autonomic regulation in endogenous depression. It was based on estimation of heart rhythm reactivity to physiologic stimuli with regards to the dependence between the severity of anxiety and the reactivity. In thirty healthy subjects, fourteen neurotics and thirty patients with endogenous depression intensity of anxiety and depression symptoms was measured. The measurements included: heart beat rate and respiratory rate in rest, amplitude of heart rhythm changes during normal breathing and both during hyperventilation and Valsalva test, the time of duration of heart rhythm acceleration in Valsalva test, and the index of termination of heart beat rate in hyperventilation test. It was proved the domination of excitability and reactivity to weak and short stimuli, and the functional dominance of sympathetic system in endogenous depression. No dependence was found between autonomic system reactivity in depression and the intensity of anxiety. The results may indicate that one part of vegetative disturbances in endogenous depression is not connected with anxiety but results from other pathogenetic mechanisms of depressive syndrome.