LOW
HDL CHOLESTEROL AMONG AMERICAN INDIANS, HYPERCHOLESTROLEMIA IN JAMAICA AND A
CUBAN/AUSTRALIAN MEDICAL ANTHROPOLOGIST
In
the Medical Literature, there has been a lot of hullabaloo made about the
importance of a Low HDL Cholesterol, the so called Good Cholesterol and
millions of dollars spent by Pharmaceutical companies to find a drug to raise
it, but to no avail. Also they sadly found out that manipulating the HDL
cholesterol to a higher level does not actually benefit the Heart!
The
Low HDL cholesterol levels among the group I work with, The Indians of North
America have puzzled me. Also had become
aware of the fact that HDL cholesterol is lower among many groups. The only
common link I could find was one of change in Lifestyle in conjunction with Oppression
or Alienation.
Science
offered no help until recently when I read an article from our colleagues from
Mesoamerica. Mexican researchers studying various American Indian groups were
able to make some observations about ABC A1, ATP binding Cassette Transporter A
1 gene associated with low HDL cholesterol. They also found an association
between this gene and Obesity and Type 2 Diabetes.
ABC
A1 plays a key role in the cholesterol efflux and transfer from peripheral
cells to lipid poor Apo lipoprotein A1 (ApoA1) the first step in the HDL
particle formation.
A
variant of this gene, C230, has only been found in Native Americans. No other
groups in the world, Africans, Melanesians or Chinese have this allele.
This
finding has tremendous implications.
From
Western Alaska (Aleutian Islands) to Tierra del Fuego (Chile and Argentina)
there are millions of Native Americans and in countries like Mexico, Guatemala,
Peru and Bolivia there are millions more descendants of Native Americans. It is
present across language divides among the Native Americans, decreasing only in
the colder climates, which they postulate to be climate related adaptive
processes.
(C230 allele in various native american groups, absent in other groups from other countries)
Overall,
HYPOALPHALIPOPROTEINEMIA (HA) was the most common form of dyslipidaemia in this
study: 65 percept of Mexican and South American Natives had it.
This
variant is also associated with Obesity (which may have been contributed by the
Newcomers to the continent from Europe, who were not known for their kindness,
by forcing lifestyle changes). Most
Native Americans in South America are not obese but most North American Native
American groups are overweight or obese.
What
is very interesting is that, this allele is exclusive to Native Americans and
their descendants.
Mexican
Americans as they are labelled in the USA are not Native Americans but they
have a fair bit of Indian admixture, and this is blamed for the high rate of
obesity and type 2 Diabetes among them in the USA and also in Mexico (much
evident after the North American Free Trade Agreement),
In
1962, Dr JV Neel had hypothesized a “Thrifty Gene” theory. Working closely with
American Indians and observing other indigenous people, I strongly believe in
the presence of this “thrift” in the metabolism of Indigenous peoples.
In
the hunter-gatherer populations such as the Native Americans, the R230 C
carriers could have had a selective advantage. Its presence prevents
cholesterol efflux; this could favour intracellular cholesterol and energy
storage during the times of Famine.
This
natural protection became a curse. During famine, it accommodated the
fluctuations in energy, provided energy for important functions such as
Reproduction and more importantly the Immune System. (Which costs a lot of
energy to maintain!)
It
is not this genetic variant cursed the American Indian to become overweight and
obese, but this trait became a liability when contact with outsiders created a
lifestyle change, with increasing Body Mass Index, Type 2 Diabetes etc.
So
by itself low HDL-C in an Indian or Indian descendant is not a disease, but a
hint, in the modern times, to look elsewhere: Lifestyle changes and an
important signal to counsel them on a Lifestyle change to one that resemble
their Ancestral Lifestyle. This may also be partially responsible for the Fatty
Liver seen among Native Americans and Mexican Americans.
Just
around the time I began working with American Indians, I was also running Free
Clinics for the Rural Poor in Jamaica who had high rates of Hypertension and
Diabetes. To run these clinics, one needed help from all sectors of that very
divided society. A prominent family had consulted their Endocrinologist in
Miami (rich Jamaicans to this day seek their medical care in Miami), he had
told them, both the mother and daughter had high cholesterol levels and had
prescribed treatment of the day, which were creating some complications. In
those days, when requesting Cholesterol levels one got different Lipoprotein
factions and unlike today, no calculated values are recorded. (That is why in
most of today’s lab reports; the sum of the calculated cholesterol values may
be higher than the total cholesterol reported). Some friends at the University
of Miami Chemical Pathology department afforded me some free testing of blood;
I tested all the family members. Even I, as a novice endocrinologist but very
well interested in medicine outside the body, could see that all members of the
family were healthy, without any evidence of heart related conditions or risk
factors for such. I was gratified to present the report to the family that they
had HYPERALPHA LIPOPROTEINEMIA, something quite opposite to what I had been
discussing above.
How
to tie it all together? To complete the circle so to speak?
Rescue
arrived in the form of research from Sao Paolo endocrinologists (published on 22
November 2013). They had hypothesized that plasma HDL-C concentrations
independent of Overweight and Obesity might be influenced by Insulin
Sensitivity.
One
is reminded of all the pharmaceutical attempts to raise the HDL-C, which has
ended up in failure so far!
In
their studies of measurements of various proteins, in lean, low HDL C and high
HDLC (like our Jamaican friends in question) they demonstrated that the
protection offered is related to Insulin Sensitivity!
This
observation has tremendous implications for the non-European, non-African
populations of this world and especially with the groups that I work with: The
Indigenous peoples.
In
a paper published in 1972, the mavens of the media, later the troubadours of
tragedy, those epidemiologists studying the Pima Indians, trumpeted:
Unexplained
Hyperinsuinaemia among the PIMA Indians compared to the Caucasians.
Diabetes
26: 827-840, 1972
Insulin
Sensitivity, Insulin Resistance and Diabetes among the groups I work with have
been in my thoughts for years, trying to make sense of it all, away from the
pronouncements based on other races and other countries, irrelevant socially,
economically to the tragic reality of the Indigenous peoples.
An
erudite colleague of mine from University of Texas Medical Branch at Galveston,
Dr Charlie S, had asked me to look for the prevalence of Acanthosis Nigricans
(the dark velvety markings on the nape of the neck one can easily see) among
the Native Americans. A casual survey was surprising. Up to 1/5 children and
1/3 adults had this marking. For the next five years, we systematically did
anthropometric measurements on hundreds of Indian children and dutifully
recorded them. We couldn't fully understand the significance of Acanthosis
Nigricans in Indian children, until Dr Charlie S, found a way to measure
insulin levels without being too intrusive.
Antibodies to insulin were
incorporated into circles in a blotting paper to which one drop of blood was applied,
which later was mashed up and measured for insulin levels.
Imagine
our surprise when we found out that almost all American Indian children had
higher than normal levels of Insulin levels and those with Acanthosis Nigricans
had higher Insulin levels.
(it was my pleasure to travel to Tsumkwe in Namibia and check the Insulin levels of Healthy San Hunter Gatherers and as expected it was higher than normal, no obesity or Diabetes known among them)
It
also fitted into the Thrifty Gene theory, which necessitated a storage hormone
to store the energy at times of plenty and to release it when there was a
shortage of energy. Insulin was the strong contender
for it. And still is!
From
this and an anthropological analysis, I was able to put forward a holistic
explanation.
Indians
were and some of them are still INSULIN SENSITIVE, which protected them against
Obesity
Type
2 Diabetes
Non
alcoholic Fatty Liver Disease.
The
onslaught of outsiders with their peculiar lifestyle and eating habits,
combined with oppression, powerlessness, alienation and marginalization became
INSULIN RESISTANT.
It
is this conversion that makes them overweight, obese, dyslipidaemic and
Diabetic.
Here
is where the Anthropological education comes in handy. It differs dramatically
from the Biomedical Education such as we are given at Medical School in that it
is
Qualitative
It
asks the question WHY and not tries to answer it with WHAT which is what the
biomedicine does
It
takes into consideration the lived in life of the person rather than just the
body as it happens in Biomedicine.
My
erudite friend from Miami, has this capacity to ask WHY? And he can come up
with searing answers that light up another pathway. He asked me, what if HDL-C
is just a marker for something else. Here is your answer, my dear friend: It
is.
We
will ask some more WHY!
Studies
like this help us alleviate the suffering of the Indigenous people of OUR
AMERICA.
Thank
you, dear researcher friends from Meso America and Brasil!
And
to Brunel University for giving me such a wonderful Medical Anthropology
education.
At
a conference given at the Potawatomie Tribe of Kansas in 2006, I had suggested
that social factors converted them from being Insulin Sensitive to Insulin
Resistant.
