The Influence of Alcohol-Induced Cerebellar Atrophy on Respiratory Rhythms at Rest

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Summary - The aim of this paper is to examine whether and in what way an alcohol-induced cerebellar degeneration changes breathing at resting. The subjects are alcohol addicts from the Club of Treated Alcoholics »Split« (N=Il), men aged between 38 and 64 yrs, smokers, abstinent from alcohol more than five months. The diagnosis of alcohol dependence made by the specialist in psychiatry according to the criteria of International Classification of Diseases (ICD-IO, tenth revision) and signs of cerebellar degeneration on magnetic resonance (MRI) were set as criteria for the inclusion in the research. Ventilation, rhythm of breathing, and pulmonary gas exchange were measured with the method of breath-by-breath (breathing with a mask) during 20 minutes of resting. The control group consists of healthy men (N=Il) who did not have problems with excessive drinking of alcoholic beverages and whose mean age corresponds to the subjects' mean age. The alcoholics and control groups statistically significantly differed in these parameters: diffusing capacity for carbon monoxide (DLCO) (p=0.002), oxygen pulse (V02/HR) (p=0.019) and alveolar ventilation (VA) (p=0.023). The subjects who had a severe atrophy of cerebellum at magnetic resonance had a lowered diffusion (DLCO) (p=0.072), increased frequency of breathing (fb) (p=0.059), and the exhalation time (TE) was shortened (p=0.018) when compared to the subjects with mild atrophy. Patients with the radiologic diagnosis of alcohol cerebellar degeneration have normal ventilation at rest, rhythm of breathing and pulmonary gas exchange which is a consequence of high physiological reserves. Strong cerebellar atrophy moderately increases the frequency of breathing and shortens the expiration which points to the fact that cerebellum is an important regulator of the breathing frequency. DLCO is lowered as well, which can be connected to smoking. The subjects are a variable group with a big dispersion of morphology and function and in order for the insufficiency of centrai respiratory control to be showed further pressure studies are necessary to be done. In order to test the peripheral and central chemosensitivity a research with hypoxic and hypercapnic test at rest and during activity should be conducted.

Keywords: alcoholism; cerebellar degeneration; breathing; magnetic resonance

INTRODUCTION

Breathing is a function essential to life and is under control of numerous anatomic structures of the central nervous system.1

Since 1991, when Pre-Bòtzinger complex was first mentioned as an area in the brain stem whose role is to generate the basic rhythm of breathing in mammals, until today there have been numerous researches trying to find out how and why we breath.2 Recent studies show the involvement of cerebellum i.e. its deep nuclei, especially nucleus fastigii in the regulation of breathing.3 Past researches on the influence of cerebellum to the respiratory function were mostly done on animals and the data on similar studies on humans are scarce. So, research is necessary in order to make clear in what way cerebellum damage contributes to the pathophysiology of numerous conditions (obstructive apnea, Congenital Central Hyperventilation Syndrome, hyperpnea when required to meet demand), as well as to increase their understanding and improve therapeutic possibilities. One way of studying neural control of breathing in humans is to research cerebellum damage in alcoholics since cerebellar degeneration, which typically occurs after ten or more years of excessive alcohol intake,6 is frequent in their case.4·5 The assumption is that neuronal dysfunction which in alcohol addicts is caused by cerebellar degeneration will change eupneic breathing.

SUBJECTS AND METHODS

Subjects

The subjects were 1 1 alcohol addicts from the Club of Treated Alcoholics »Split« aged between 38 and 64. The criteria of inclusion into the research were the diagnosis of alcohol dependence and signs of cerebellar degeneration on magnet resonance (MRI). …