ARTERIAL HYPERTENSION

FREDERICK M. ALLEN
1920 Journal of the American Medical Association  
The great importance of arterial hypertension or the conditions associated with it, as a widespread and apparently increasing cause of disability and death, is a self-evident incentive to investigation. At the same time it must be recognized that our knowledge of the subject is in a very confused state, as respects its phases of etiology, mechanism and treatment. Just as with diabetes, the literature contains almost every conceivable variety of opinions and suggestions. The first task of an
more » ... irst task of an investigator to choose is what seems significant and valuable among this mass of conflicting material, and the second is to build concrete facts with accurate methods in a clinical field which is still largely a morass of tradition and imagination. THEORIES REGARDING THE CAUSES OF HYPERTENSION More or less restriction of salt has been employed for many years by some observant clinicians in the treatment of the various forms of nephritis. The first scientific foundation of both theoretical and practical importance is afforded by the work of the French school, beginning with Widal's demonstration of the rôle of the chlorids, particularly in the causation and treatment of edema, and with the application of this principle to hypertension by Ambard,1 Combe,2 Laufer 3 and others. Similar results were obtained in arteriosclerosis by Bayer ; 4 but with only a few excep¬ tions the tests with nephritis in Krehl's clinic were negative or doubtful, and the general German experi¬ ence was opposed to a strict relationship between reten¬ tion of chlorids and elevation of blood pressure.5 In American literature, salt and fluid restriction in hypertension is mentioned casually and incompletely if at all, and the protein intoxication theory is undoubt¬ edly the dominant one. Treatment consists chiefly in low protein diets, the elimination of supposed toxins, or the artificial reduction of pressure by drugs, bleeding, electricity, and the like. Mental and bodily rest is advised to a degree which largely terminates usefulness in life, and many conservative practitioners refrain from any serious attempt to reduce the pressure, and devote themselves to keeping the patient as comfortable as possible, with resignation as to the results. There are various reasons for this confusion and pessimism. In the German work the cases were not always well chosen and the restriction of salt was gen¬ erally inadequate, though this work does furnish evi¬ dence against any invariable association of hypertension and gross chlorid retention. On the other hand, whether or not protein has any influence on blood pres¬ sure, it is impossible to accept Ambard's assertion that it is harmless in nephritis. Ambard considers fluid restriction unnecessary, and in adopting milk diet he comes back to the identical therapeutic program used Read before the by the followers of the intoxication hypothesis. The fluid restriction of Laufer, who accepts von Noorden's v limit of a liter daily without reckoning the important ' additional quantities contained in the food, is too lax for the worst cases. Likewise a much stricter exclusion of salt than represented by milk diet is essential for results in really severe cases. These inaccuracies are responsible for an unnecessarily high percentage of cases of absolutely or relatively irreducible hyperten¬ sion in French, German, American and all other records, and also for the unnecessarily frequent and early deaths from apoplexy, cardiac failure, pul¬ monary edema and convulsions (misnamed uremie). For the same reason there have been no differences in therapeutic results sufficiently marked to establish any one theory to the satisfaction of all parties. RESTRICTION OF WATER AND SALT It would be wrong to ignore the unknown and uncon¬ trollable factors in hypertension and the unsolved prob¬ lems which they present. But any practitioner who will conform his treatment to one reasonable and definite condition, namely, the necessity of the organism to force a filtrate of water and dissolved substances through a damaged and partially blocked glomerular filter, can readily demonstrate for himself the com¬ pensatory element in the hypertension, by observing the fall in pressure and the relief of some attendant symp¬ toms when proper diet reduces the quantity of this filtrate to a minimum. The opposite treatment under the intoxication hypothesis, through unsuitable diets and attempts at "flushing out," entails much harm. In some hypertension cases the mere reduction of the overload of salt and water brings relief which is com¬ parable to the benefits of diet in diabetes. Fuller laboratory study, particularly by blood anal¬ yses, contributes new information of theoretical, prognostic and therapeutic importance. Among the nephritic cases treated in our clinic to date, there have been twenty examples of marked hypertension. Most of these were treated in private hospital status, but four were outpatients. The observations are neces¬ sarily empiric, and are subject to modification from wider clinical experience, and particularly to more fundamental and decisive interpretations when animal experiments become available. Numerous data of these cases, function tests according to Ambard's principles, and details of individual histories and results, must be reserved for a more complete publica¬ tion at a later date. It may suffice here to state that the patients' ages ranged from 25 to 69 years, with the usual predomi¬ nance of those past 40. All the cases were of chronic type. Their severity was mostly too great to yield to mere rest and hospital care, and some were known as highly severe cases which had proved intractable to a variety of customary treatments for several years. Bleeding was used temporarily in three critical cases, and brief experiments have been tried with some other measures ; but in general the patients were not kept in bed or confined to the house but were treated entirely by diet. To establish the general principle, the effects of sud¬ den dosage with salt or water in suitable cases are illustrated by two experiments. In the first experiment (Table 1), attention may be called to the absence of real retention of either salt or water (contrary to the French reports), and to the Downloaded From: http://jama.jamanetwork.com/ by a University of Manitoba User on 06/13/2015
doi:10.1001/jama.1920.02620100012005 fatcat:dqbs3kc4xrdebgqmxzsp4yv2ri