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One of the most serious challenges to all physicians is the maintenance of therapy for those chronic disorders that at present cannot be cured. Elevations of low-density lipoprotein and very low-density lipoprotein are among the most common of those disorders. We are now in an era in which 2 fundamental developments of modern technology have come together. These are the supply of effective and safe lipid-lowering drugs as well as the ability to closely monitor pertinent measures in our patients. The rapid conversion of our health care systems into large teams of professionals with direct support from third-party payers has made it possible to coordinate chronic care through electronic medical records and electronic communication. As a result, with effective planning and organization, we can guide our patients toward better adherence to successful medical regimens. These issues are evolving rapidly and have been presented in some detail in the December 2013 issue of the Journal. I was joined in this Roundtable discussion by 3 health professionals who have had extensive experience with the application of health information technology. They are Dr. Karen Aspry and Dr. Alan Brown, both clinical cardiologists, and Dr. Matthew Ito, a Doctor of Pharmacy., (Copyright © 2014 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

In the two genetic forms of abetalipoproteinemia described previously, recessive abetalipoproteinemia and homozygous hypobetalipoproteinemia, all lipoproteins that normally contain apolipoprotein B are absent from plasma. We describe here a new disorder in which normal low density and very low density lipoproteins are absent, but in which triglycerides are absorbed from the intestine and chylomicrons are present in plasma. The underlying molecular defect appears to be selective deletion of the hepatogenous B-100 apolipoprotein. The B-48 apolipoprotein found in chylomicrons is spared. These findings suggest that the two species of apolipoprotein B are under separate genetic control and that low density lipoproteins are not normally derived from chylomicrons.

Serum from two patients with abetalipoproteinemia, a rare disorder of lipid metabolism characterized by the absence of chylomicrons and very low density and low density lipoproteins, did not stimulate the proliferation and growth of human smooth muscle cells or dermal fibroblasts in vitro as effectively as normal serum. The growth-promoting activity of this serum was comparable to that observed for lipoprotein-deficient plasma from normolipidemic subjects. Although the mitogenic effect of abetalipoproteinemic serum was improved with supplementation of low density lipoproteins, it was still about half the activity achieved with normal serum. However, the growth-promoting activity of this serum was completely restored to normal levels after addition of a lysate of normal platelets. In contrast, the mitogenic activity of lipoprotein-deficient plasma remained unchanged after addition of a lysate from abetalipoproteinemic platelets, whereas a similar supplementation of normal platelets completely restored its growth-promoting activity to normal. Thus, the inability of abetalipoproteinemic serum to promote growth appears to be due both to a deficiency of a platelet-releasable growth factor(s) and to the absence of serum lipoproteins.