Gastrointestinal mobility in chronic alcoholics

Abstract

The studies presented in this thesis attempt to extend the current understanding of the long-term effects of chronic alcoholism on gastrointestinal motility and the pathogenesis of alcohol related motility disturbances. Chapter 1 discusses the physiology of gastrointestinal motility and effects of alcohol on the gastrointestinal tract with special reference to the problem of alcoholism in Sri Lanka. Chapter 2 compares the results of ambulatory oesophageal manometry and pHmetry in 23 chronic alcoholics and 15 control subjects. The study shows for the first time that chronic alcoholism changes the circadian oesophageal motility pattern. Motility disturbances, such as the failure to increase the percentage of peristaltic waves during the meal period were found to be related to alcoholic autonomic neuropathy. Autonomic neuropathy was also found to be partly responsible for lower oesophageal sphincter hypertension in alcoholics. Changes in contraction amplitude and duration in the distal part of the oesophagus during meal and supine periods were also observed in alcoholics irrespective of the presence of alcoholic neuropathy. Chapter 3 studies the influence of meal consistency on gastric myoelectrical activity using iso-caloric (170 kcal) carbohydrate test meals of different consistency. According to the results obtained from 18 healthy subjects, the solid and the semisolid test meals are capable of increasing the power of the postprandial EGG, while the liquid meal failed to do so. In chapter 4 gastric myoelectrical activity was studied in 18 chronic alcoholics and 10 control subjects using a solid carbohydrate test meal (375kcal). Alcoholics with autonomic neuropathy showed a significantly lower incidence of normal 3cpm wave activity in the postprandial period. Irrespective of the presence of neuropathy, alcoholics failed to increase the power of the EGG following the test meal. In chapter 5, assessed mouth to caecum transit time and colonic transit time as a measure of intestinal motility in 18 alcoholics and 21 control subjects. Lactulose breath test showed a significantly shorter mouth to caecal transit time in alcoholics irrespective of whether they had diarrhoea or not. Rapid intestinal transit seems to have no association with the presence of alcoholic autonomic neuropathy. Assessment of colonic transit using the radiopaque marker ingestion technique failed to show any significant difference in the rate of marker excretion in the alcoholic group compared to the control group. Chronic alcoholism is associated with altered circadian oesophageal motor activity, disturbed postprandial gastric myoelectrical activity and rapid small intestinal transit. The presence of oesophageal motility disturbances and postprandial EGG disturbances together (in alcoholics subjected to both oesophageal manometry and electrogastrography) shows the ability of alcohol in interfering with motor functions of more than one organ at a time. Altered circadian oesophageal motility and postprandial EGG disturbances could partly be attributed to alcoholic autonomic neuropathy.