Vitamin Information Center

Centers for Disease Control
and Prevention (CDC)
Definition
The Centers for Disease Control and Prevention (CDC)
was founded 60 years ago to help control malaria.
Today it is the leading U.S. government agency of the
Department of Health and Human Services for protecting
the health and safety of the people of the U.S.,
with the following vision for the 21st century: “Healthy
People in a Healthy World – Through Prevention”.
The CDC focuses national attention on prevention and
control of infectious and chronic diseases, disabilities,
injuries, and environmental health threats. It is headquartered
in Atlanta, Georgia.

Burden of Disease
FRANZ HESSEL
Health Economics Outcomes Research, Sanofi-Aventis
Pharma GmbH, Berlin, Germany
franz.hessel@sanofi-aventis.com
Synonyms
Burden of illness; Cost of illness
Definition
The term burden of disease generally describes the
total, cumulative consequences of a defined disease or
a range of harmful diseases with respect to disabilities
in a community. These consequences include health,
social aspects, and costs to society. The gap between
an ideal situation, where everyone lives free of disease
and disability, and the cumulated current health status,
is defined as the burden of disease.
In the 1990s, theWorld Health Organization (WHO),
in co-operation with Harvard University and the World
bank, developed a methodological concept to quantify
the global burden of disease; this was based to a large
extent on statistical measurement of the  disability-
adjusted life year (DALY). The DALY aggregates
the time lost because of premature mortality and the
time spent in a limited health state. Consequently, the
DALYs for a defined disease or health condition are
calculated as the sum of the years lost due to specific
premature mortality and the years lost due to disability
for incident cases of the health condition.
Basic Characteristics
The burden of illness or burden of disease approach
used in public health and the epidemiological literature
combines measurement of mortality and morbidity
with respect to non-fatal outcomes such as quality
of life aspects. With regards to these basic attributes,

burden of illness-concepts – and especially the DALY –
include some key elements of utility-concepts, such as
the QALY ( value, human life – utilities). However,
due to the lack of foundation in economic theory, burden
of illness is primarily seen as a descriptive epidemiologic
concept, such as the regular burden of disease
report of the US Center for Disease Control (Centers
for Disease Control and Prevention 2004). Although it
is possible to express the gain from the avoided loss of
burden of disease relative to additional costs, this specific
cost-outcome relation is very rarely found in the
literature and is not regarded as a common health economic
measure.
The most well-known and widespread concept following
the burden of disease principle is the DALY (Homedes
1996). DALYs represent one key element in the
WHO ranking of worldwide health care systems “The
global burden of disease” (Mathers et al. 2003; Murray
et al. 1997; Lopez et al. 2006). The first results of this
project, for the year 1990, have been published, with
regular updates and extension being carried out (Murray
2007; WHO 2007).
The cumulated disease-specific DALYs, aggregated
according to the country-specific prevalence of the diseases
and disabilities considered, reflect the burden of
disease of a specific society or a specific country. The
Global Burden of Disease concept of the WHO compares
large numbers of low-, middle- and high-income
countries with regard to their country-specific burden
of disease. It offers mortality figures, which refer to
the number of people who die and the causes of death.
Thus, a comprehensive and consistent set of estimates
of mortality and morbidity expressed by the single indicator
DALY and differentiating by age, sex, and region,
is given.
There are some specific aspects of the DALY concept,
such as further time discounting and non-uniform
age weights, which give less weight to years lived at
a younger age. According to this concept, the death
of an infant is equivalent to 33 DALYs and the death
of a person between 5 and 20 years of age is about
36 DALYs. Consequently, the death of 100 infants in
a society would be equivalent to 3,300 DALYs, which
corresponds to 5,500 persons with blindness at an age
of 50 years. The weight factors reflecting the severity
of the disability or disease (e. g. the disability weight for
blindness of 0.6) were originally defined by international
experts. New concepts using health-related quality of
life and utility concepts are currently being implemented.
In recent decades in most western industrial nations,
a clear tendency regarding the burden of disease can
be observed. There is an ageing of societies, with
a decrease in mortality, accompanied by an increase in
morbidity. The increase in morbidity is mainly due to
an increase in the prevalence of chronic diseases and
risk factors such as cardiovascular disorders, cancer,
diabetes, and obesity. Mortality estimates are higher in
low- and middle-income countries than in high-income
countries. People in low- and middle-income countries
die at a much younger age. In Africa, mortality is mainly
cause by infectious diseases – mainly HIV/AIDS and
malaria – which affect younger shares of the population
comparedwith China, where the pattern of diseases
is dominated by non-infectious diseases. The burden
of disease in Africa is estimated to be more than four
times higher than in high-income countries. The populations
of Africa and India represent about one third
of the population of the world, but the burden of disease
in these two regions is nearly half of the total global
burden of disease. Furthermore, the health inequities
gap is widening in a considerable number of countries.
The WHO Global Burden of Disease report from 2002
(Lopez 2006) reports three major trends: slowing down
of gains and widening of health gaps; increasing complexity
of the burden of disease; and globalization of
adult health risks.
Although an improvement in health conditions and burden
of disease has been observed in many low- and middle-
income countries over the last decade, a large proportion
of risk factors and diseases are still preventable,
e. g. about one-fifth of the global burden of disease can
be attributed to under-nutrition. In Africa about onefifth
of the burden of disease is attributed to unsafe sex
leading to HIV and other sexually transmitted infections.
Concerning high-income countries, tobacco consumption
is the leading avoidable risk factor, accounting
for 12 per cent of the burden of disease. Globally,
about 42 per cent of the total burden of disease can
be attributed to the leading 10 risk factors when joint
effects are taken into consideration. The leading five
risk factors are responsible for about one quarter of the
total loss of healthy years of life. These figures demonstrate
the enormous potential for improving mortality
and morbidity by prevention and decrease of wellknown
risk factors. This underlines the importance of

research to develop cost-effective strategies for a relatively
small number of risk factors to reduce a relatively
large share of the global burden of disease (Mathers
2003;Murray 2007).
Cross-References
 Disability Adjusted Life Years (DALYs)
 Value, Human Life – Utilities
WHO
References
Center for Disease Control and Prevention (2004) The Burden of
Chronic Diseases and their Risk Factors. CDC, Atlanta, USA
Homedes N (1996) The Disability-Adjusted Life Year (DALY).
Definition, Measurement and Potential Use. Human Capital
Development Working Papers No. 68. Worldbank, Washington
Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CL
(2006) Global and Regional Burden of Disease and Risk Factors,
2001: Systematic Analysis of Population Health Data.
Lancet 367:1747–1757
Mathers C, Bernard C, Iburg K, Inoue M, Ma Fat D, Shibuya
K (2003) Global Burden of Disease in 2002: data sources,
methods and results. GPE Discussion Paper No. 54. World
Health Organization, Geneva
Murray CL (2007) Towards Good Practice for Health Statistics:
Lessons from the Millenium Goal Health Indicators. Lancet
369:862–873
Murray CJ, Lopez AD (1997) The Global Burden of Disease.
A Comprehensive Assessment of Mortality and Disability
from Diseases, Injuries, and Risk Factors in 1990 and projected
to 2020. Harvard University Press, Harvard
World Health Organization (2007) Global Burden of Disease.
http://www.who.int/topics/global_burden_of_disease/
en/. Accessed October 4th 2007

AIDS
Synonyms
Infection with the human immunodeficiency virus;
Acquired immunodeficiency syndrome; HIV-infection;
HIV/AIDS
Definition
HIV (human immunodeficiency virus) is a retrovirus
that primarily infects vital components of the human
immune system such as CD4+ T cells (a subset of T
cells), macrophages and dendritic cells. It impairs the
body’s ability to fight infection and certain cancers.
HIV infection is diagnosable by antibody or antigen
testing. Treatment aims to suppress HIV replication
by combinations of drugs that inhibit HIV enzymes.
Any of a list of illnesses that, when occurring in an
HIV-infected person, leads to a diagnosis of AIDS, the
most serious stage of HIV infection. AIDS is also diagnosed
if an HIV-infected person has a CD4 count below
200 cells/mm3, whether or not that person has an AIDSdefining
condition. The Centers for Disease Control and
Prevention (CDC) published a list of AIDS-defining
conditions in 1993. The 26 conditions include candidiasis,
cytomegalovirus disease, Kaposi’s sarcoma,
mycobacterium avium complex, pneumocystis carinii
pneumonia, recurrent pneumonia, progressive multifocal
leukoencephalopathy, pulmonary tuberculosis, invasive
cervical cancer, and wasting syndrome.
Cross-References
 HIV (Human Immunodeficiency-Virus)-Infection
 HIV-Infection and AIDS

Nearly 200 people across the country have been sickened after taking the vitamin supplement Total Body Formula, United Press International reported Sunday.

The Centers for Disease Control and Prevention found that users of the supplement suffered loss of hair and fingernails, as well as nausea, joint pain, and diarrhea among other symptoms.

The liquid supplement is one of more than 12 supplements that have been recalled in the past year by the U.S. Food and Drug Administration.

Some batches of Total Body Formula and Total Body Mega Formula contained excessive amounts of the minerals selenium and chromium.

Selenium, a trace mineral, is only needed in small amounts for good health, the FDA said, and too much of it can cause the symptoms listed above. Chromium, also a trace mineral, can cause anemia, kidney failure, and liver damage if too much is ingested.

The company now faces lawsuits from former customers who allege they were poisoned by the product and face long-term side effects.

In March, the FDA warned consumers in 15 states about the link between the dietary supplement and adverse side effects including “significant hair loss” after 23 individuals suffered “serious reactions” within seven to 10 days of ingesting the liquid supplements.

At that time the distributor of the supplements voluntarily recalled the products, which were distributed by Total Body Essential Nutrition of Atlanta.

The products have been distributed in Alabama, California, Florida, Georgia, Kentucky, Louisiana, Michigan, Missouri, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Texas and Virginia.

Low vitamin D levels are associated with a higher risk of death, according to a report released on August 11, 2008 in the Archives of Internal Medicine, one of the JAMA/Archives journals.

Vitamin D is a group of prohormones that play important roles in calcium metabolism, bone formation, parathyroid function, and the immune system. Presently, the ideal bood levels of 25-hydroxyvitamin D (25[OH]D) has been suggested as 30 nanograms per milliliter or higher. In the United States, approximately 41% of men and 53% of women have levels lower than 28 nanograms per milliliter.

There are many potential health problems that could contribute to death in individuals with low vitamin D levels, including an effect on blood pressure, insulin response, or risk of obesity and diabetes.

To investigate the potential implications of this deficiency, Michal L. Melamed, M.D., M.H.S., of the Albert Einstein College of Medicine, Bronx, N.Y., and colleagues examined 13,331 individuals in the Third National Health and Nutritional Examination Survey (NHANES III), a large cohort study performed by the Centers for Disease Control and Prevention (CDC). These individuals were examined for Vitamin D levels between 1988 and 1994, and tracked through 2000, with a median 8.7 years of follow-up.

In this period, 1,806 participants died. When divided into groups based on vitamin D levels, the group maintaining the lowest level, defined as less than 17.8 nanograms per milliliter, showed a 26% increased risk of death from any cause in comparison with the group with the highest levels of vitamin D. This was not associated with cardiovascular disease or cancer alone.

The authors conclude that “the lowest 25(OH)D quartile (less than 17.8 nanograms per milliliter) is associated with a higher risk of all-cause mortality in the general U.S. population.” They continue: “Further observational studies are needed to confirm these findings and establish the mechanisms underlying these observations. If confirmed, randomized clinical trials will be needed to determine whether vitamin D supplementation at higher doses could have any potential benefit in reducing future mortality risk in those with 25(OH)D deficiency.”

25-Hydroxyvitamin D Levels and the Risk of Mortality in the General Population
Michal L. Melamed, MD, MHS; Erin D. Michos, MD, MHS; Wendy Post, MD, MS; Brad Astor, PhD
Arch Intern Med. 2008;168(15):1629-1637
Click Here For Abstract

Written by Anna Sophia McKenney
Copyright: Medical News Today