Fall - United States Special Operations Command

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ABSTRACTS FROM CURRENT LITERATURE
Vitamin D in Preventive Medicine: Are We Ignoring the Evidence?
Armin Zittermann
Department of Nutrition Science, University of Bonn, Endenicher Allee 11-13, 53115 Bonn, Germany
ABSTRACT
Vitamin D is metabolised by a hepatic 25-hydroxylase into 25-hydroxyvitamin D (25(OH)D) and by a renal 1α-hydroxylase into
the vitamin D hormone calcitriol. Calcitriol receptors are present in more than thirty different tissues. Apart from the kidney, several
tissues also possess the enzyme 1α-hydroxylase, which is able to use circulating 25(OH)D as a substrate. Serum levels of
25(OH)D are the best indicator to assess vitamin D deficiency, insufficiency, hypovitaminosis, adequacy, and toxicity. European
children and young adults often have circulating 25(OH)D levels in the insufficiency range during wintertime. Elderly subjects
have mean 25(OH)D levels in the insufficiency range throughout the year. In institutionalized subjects 25(OH)D levels are often
in the deficiency range. There is now general agreement that a low vitamin D status is involved in the pathogenesis of osteoporosis.
Moreover, vitamin D insufficiency can lead to a disturbed muscle function. Epidemiological data also indicate a low vitamin D
status in tuberculosis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel diseases, hypertension, and specific types of
cancer. Some intervention trials have demonstrated that supplementation with vitamin D or its metabolites is able: (i) to reduce
blood pressure in hypertensive patients; (ii) to improve blood glucose levels in diabetics; (iii) to improve symptoms of rheumatoid
arthritis and multiple sclerosis. The oral dose necessary to achieve adequate serum 25(OH)D levels is probably much higher
than the current recommendations of 5–15 µg/d.
Why is Preventive Medicine Exempted From Ethical Constraints?
P Skrabanek
J Med Ethics 1990;16:187-190 doi:10.1136/jme.16.4.187
ABSTRACT
It is a paradox that medical experimentation on individuals, whether patients or healthy volunteers, is now controlled by strict ethical
guidelines, while no such protection exists for whole populations which are subjected to medical interventions in the name of
preventive medicine or health promotion. As many such interventions are either of dubious benefit or of uncertain harm-benefit
balance, such as mass screening for cancers or for risk factors associated with coronary heart disease, there is no justification for
maintaining the ethical vacuum in which preventive medicine finds itself at present.
A Prospective Study of Plasma Homocyst(e)ine and Risk of Myocardial Infarction in U.S. Physicians
Meir J. Stampfer, MD; M. Rene Malinow, MD; Walter C. Willett, MD; Laura M. Newcomer; Barbara Upson; Daniel Ullmann,
MPH; Peter V. Tishler, MD; Charles H. Hennekens, MD
JAMA. 1992;268(7):877-881
ABSTRACT
Objective: To assess prospectively the risk of coronary heart disease associated with elevated plasma levels of homocyst(e)ine.
Design: Nested case-control study using prospectively collected blood samples. Setting: Participants in the Physicians’ Health
Study. Participants: A total of 14916 male physicians, aged 40 to 84 years, with no prior myocardial infarction (Ml) or stroke
provided plasma samples at baseline and were followed up for 5 years. Samples from 271 men who subsequently developed Ml
were analyzed for homocyst(e)ine levels together with paired controls, matched by age and smoking. Main Outcome Measure:
Acute Ml or death due to coronary disease. Results: Levels of homocyst(e)ine were higher in cases than in controls (11.1±4.0
[SD] vs 10.5±2.8 nmol/mL; P=.03). The difference was attributable to an excess of high values among men who later had MIs.
The relative risk for the highest 5% vs the bottom 90% of homocyst(e)ine levels was 3.1 (95% confidence interval, 1.4 to 6.9;
P=.005). After additional adjustment for diabetes, hypertension, aspirin assignment, Quetelet’s Index, and total/high-density
lipoprotein cholesterol, this relative risk was 3.4 (95% confidence interval, 1.3 to 8.8) (P=.01). Thirteen controls and 31 cases (11%)
Journal of Special Operations Medicine Volume 10, Edition 4 / Fall 10