b. Obesity.—Fat-infiltration and fat-accumulation must be regarded as among the most characteristic disturbances produced by alcohol. Fat is abundantly stored up in the subcutaneous tissues. The anterior abdominal wall is especially liable to its accumulation. The heart, kidneys, omentum, and mesenteries are also not infrequently the seat of abnormally large accumulations of fat. Fat also collects in the muscles and in the intermuscular planes, but to a less extent. Obesity is not, however, so frequent in the advanced stages of alcoholism as it is while the subject has not yet lost the appearance of health, and in a large proportion of the individuals it does not manifest itself at all. It appears to depend largely upon the character of the drink, and is especially frequent among those addicted to excesses in beer. It is less common among wine-drinkers, and relatively infrequent and of moderate degree in those who confine themselves to spirits. A sedentary life, and perhaps also an hereditary tendency, exerts an important influence upon the development of obesity in alcoholism.
c. Alcoholic Cachexia.—The action of alcohol in excessive amounts upon the nutrition of the body at large, and in particular upon the nutrition of the nervous system, is radically unfavorable. This unfavorable influence manifests itself from the beginning, while the subject yet presents the appearance of health, and long before the occurrence of either the symptoms or physical signs of organic disease. The powers of resistance to unfavorable influences of all kinds are diminished; the ability to endure hardships, privations, and fatigue is lessened; sickness and injuries are badly borne; complications are frequent and grave; and convalescence is apt to be tardy and insecure. It is among the more striking peculiarities of the alcoholic subject that blood-losses are badly borne and slowly repaired. It is this want of tone, often latent for a long time under ordinary circumstances, which unfits those addicted to alcohol for Arctic and exploring expeditions and for military and scientific enterprises involving prolonged hardship and exposure. In the course of time disorders of the digestion, of hæmatosis, of circulation, increase the difficulty and render it more apparent. The fat now rapidly diminishes; anæmia develops; the complexion becomes dull, earthy, or slightly jaundiced, the tissues flabby. Then follow diarrhœa, hemorrhages from mucous surfaces, serous effusions, visceral congestions of high degree, hypostasis, œdema, and progressive deterioration of all the powers alike of the body and the mind until the dyscrasia is complete.
The subjects of chronic alcoholism are especially prone to affections of the respiratory tract and to the infectious diseases. They furnish, as a rule, the earliest victims in epidemics. They not rarely die of pneumonia. They develop troublesome delirium in simple maladies, and in all acute affections the prognosis is unfavorable as compared with that in persons of sober habits. As Clouston well says, “The whole organism suffers sanative and mental lowering, alteration of functions and of energizing.”
B. DERANGEMENTS OF THE NERVOUS SYSTEM: CEREBRO-SPINAL DISORDERS.—The disorders of the central nervous system in chronic alcoholism are even more numerous and more important than those already described. Many transient and permanent disturbances of function occur without anatomical lesions recognizable by existing methods of examination; many others are associated with readily-discoverable changes of structure. These changes are encountered in the blood-vessels, the meninges, the substance of the cerebro-spinal axis, and in the peripheral nerves. Much as they differ in appearance and in their clinical manifestations, they may all be referred to three processes: (a) congestion and inflammation; (b) sclerosis; and (c) stentosis.
1. Cerebral Disorders.—The Cranium.—The bones of the skull are often thicker and more dense than normal. This change implicates the diploë and the outer and inner tables. The last is then deeply channelled for the blood-vessels and deeply indented for the Pacchionian bodies, which are commonly hypertrophied.
The Vessels.—Disturbances of the cerebral circulation are among the earliest and most important symptoms. Due primarily to the increased action of the heart and vaso-motor dilatation of the blood-vessels excited by repeated large amounts of alcohol, and secondarily to permanent enlargement of the vessels in consequence of fatty or atheromatous degeneration of their walls, some degree of active or passive congestion is almost always present. It is probable also that in consequence of irregular and complex disturbances of the circulation secondary localized ischæmia occurs. Lentz states that anæmia is more common in the cerebral substance than in the membranes.
The capillaries are usually much altered—sometimes uniformly dilated to a considerable extent, sometimes forming capillary aneurisms. They are more sinuous than normal, their walls show evidences of fatty degeneration, and they sometimes contain minute thrombi. Extravasated blood, in the form of circumscribed collections, of diffuse layers, or finally of capillary hemorrhages, also occurs. These collections are sometimes free, sometimes encysted.
The Meninges.—The dura mater is congested; occasionally it shows more or less extensive areas of inflammation with exudation of lymph. Purulent exudation in the absence of traumatism is rare. The lymph may be deposited in the form of patches of varying extent, or it may form more or less extensive false membranes. These accumulations are of variable, often considerable, thickness, and constitute the condition described as pachymeningitis hæmorrhagica interna, or, from the large amount of blood which they contain, hæmatoma of the cerebral meninges. They occupy the convexity of the brain, and are developed upon the inner surface of the dura; they are usually nearly symmetrical in outline, but of different thickness upon the two sides. They consist of superimposed layers of lymph, between which, or within the substance of which, are more or less extensive blood-extravasations, either fluid, coagulated, or undergoing resorption. More frequently the exudation consists of mere shreds of lymph within the cavity of the arachnoid.
The arachnoid is almost invariably altered. Upon the convex surface of the hemispheres, especially along the median fissure, it is thickened and opaque. This condition may be uniform or distributed in patches, and is apt to follow the line of the blood-vessels.
The pia mater is congested, often œdematous, not rarely the seat of blood-effusions of greater or less extent.