FACTORS ALTERING CONCENTRATION OF BLOOD LIPIDS 473 



condition in man by the speed of development and also by the unusual 

 susceptibility of the former to iodine and to the activity of the thyroid 

 gland. 



b'. Gross Blood Lipid Changes in Arteriosclerosis: There is also con- 

 siderable disagreement as to whether or not hypercholesterolemia is an 

 invariable concomitant of hypertension in man, and inversely whether 

 hypertension invariably follows the exposure of the body to a hyperchole- 

 sterolemia over an extended period. A number of investigators, including 

 Fahrig and Wacker, 300 Koch and Westphal, 758 Medvei, 726 Wacker and Fah- 

 rig, 759 and Harris 760 reported that cholesterol is increased in hypertension. 

 Some workers have indicated that all blood lipids, as well, are in- 

 creased. 300,759 Alford 761 found that coronary heart disease and xanthoma 

 tuberosum are associated with hereditary hyperlipemia. Increases either 

 in the total serum lipids or in the serum cholesterol, or in both, were found. 

 Gertler and Gam 762 likewise observed that serum cholesterol was con- 

 siderably higher in males who had experienced myocardial infarction than 

 it was in healthy, active males. In the coronary disease group, both 

 cholesterol and phospholipids were increased in the serum, but the chole- 

 sterol : phospholipid ratio was likewise increased, indicating that the rise 

 in phospholipid had not kept pace with that of cholesterol. It is suggested 

 that the factors favoring the deposition of cholesterol in the intima are en- 

 hanced because of the lack of sufficient phospholipid to act as a colloid 

 stabilizer. 



On the other hand, one must recognize that hypercholesterolemia exists in 

 a variety of diseases other than hypertension. Several investigators are of 

 the opinion that a normal cholesterol level may occur in hypertension 

 unless a concomitant disorder such as nephritis is likewise pres- 

 ent. 210,697,725,763,764 The occurrence of hypertension is not considered to be 

 adequate proof of the existence of atherosclerosis. 202 



c'. The Relationship of the S f 10-20 Fraction to Atherosclerosis: 

 Gofman and his associates 96 - 98 have advanced an attractive theory to ex- 

 plain the relationship of blood cholesterol to atherosclerosis. These 

 workers point out that, while the total serum cholesterol level may ex- 

 hibit no uniform relationship to hypertension, the concentration of the 



768 K. Koch and K. Westphal, Deut. Arch. klin. Med., 181, 413-484 (1937-1938). 



759 L. Wacker and C. Fahrig, Klin. Wochschr., 11, 762-766 (1932). 



760 I. Harris, Lancet, 257, 283-285 (1949). 



761 R. M. Alford, Arch. Internal Med., 84, 1002-1019 (1949). 



762 M. M. Gertler and S. M. Garn, Science, 112, 14-16 (1950). 



763 I. Harris and I. J. Lipkin, Brit. Med. J., 1930, 1, 587-588. 



764 1. H. Page, E. Kirk, and D. D. Van Slyke, /. Clin. Invest., 15, 109-113 (1936). 



