Not fasting before cholestoral exam

Jack Steele said:

How does failing to fast before a cholestoral exam affect the results?

Can raise triglycerides an extraordinary amount.

Quoted message said:

Does it make them more noisy or skew them in a certain direction?

Elevated triglycerides can skew cholesterol measurements upwards.

Humbly,

Andrew

--
Dr. Andrew B. Chung, MD/PhD
Board-Certified Cardiologist
heartmdphd.comheartmdphd.comOpen ↗

(Jack Steele) said:

How does failing to fast before a cholestoral exam affect the results?
Does it make them more noisy or skew them in a certain direction?

I think the most important message is if you doctor is trying to determine if you need a certain
level of therapy, each and every test must be performed in the standard fasting state. Trigs are
especially skewed upwards with caffiene. Smoking can influence lipid profiles adversly. You may
drink water before the test, however.

Sometimes oral fat loading lipid profiles can help determine undetected abnormalities with normal
fasting profiles:

Metabolism. 2004 Jan;53(1):49-53. Daytime triglyceridemia in normocholesterolemic patients with
premature atherosclerosis and in their first-degree relatives. Geluk CA, Halkes CJ, De Jaegere PP,
Plokker TW, Cabezas MC.

Postprandial hypertriglyceridemia tested under metabolic ward conditions with unphysiological high
fat loads has been reported in CAD patients and their relatives even in the presence of normal
fasting lipids. It is unclear whether this also occurs in the daytime situation. Twenty-seven
normocholesterolemic, non-obese and nondiabetic patients with premature coronary artery disease
(CAD) and 56 first-degree relatives without CAD measured daytime capillary triglyceride profiles (TGc-
AUC) as an estimate of postprandial lipemia. Fasting capillary triglycerides (TGc) were not
significantly different between CAD index patients and their relatives (1.68 +/- 0.63 and 1.54 +/-
0.71 mmol/L, respectively). In contrast, daytime triglyceridemia was significantly higher in CAD
patients (30.7 +/- 13.6 mmol. h/L) compared to their relatives (24.4 +/- 9.4 mmol. h/L) and this was
also the case after correction for fasting TGc (7.24 +/- 7.41 and 2.79 +/-
6.89 mmol. h/L; P <.05). The best predictors of TGc-AUC by multiple regression analysis in CAD
families were fasting TGc, systolic blood pressure, and high-density lipoprotein cholesterol (HDL-
C), which are all components of the metabolic syndrome, explaining 65% of the variation. Since
there were no major differences in nutritional intake between index patients and their
relatives, this could not explain the differences Daytime triglyceridemia, measured under
physiological conditions, is increased in patients with premature atherosclerosis and normal
fasting TG levels, when compared to their non-CAD relatives. This study confirms previous
observations using standardized oral fat loading tests and underlines the importance of
postprandial hyperlipidemia in CAD.

--
Winning against heart attack and stroke sonoscore.comsonoscore.comOpen ↗

I have no medical training. Is the point that if not fasting increases triglycerides significantly,
there is a higher likelihood of CAD?

Quoted message said:

Sometimes oral fat loading lipid profiles can help determine undetected abnormalities with normal
fasting profiles:

Metabolism. 2004 Jan;53(1):49-53. Daytime triglyceridemia in normocholesterolemic patients with
premature atherosclerosis and in their first-degree relatives. Geluk CA, Halkes CJ, De Jaegere PP,
Plokker TW, Cabezas MC.

Postprandial hypertriglyceridemia tested under metabolic ward conditions with unphysiological high
fat loads has been reported in CAD patients and their relatives even in the presence of normal
fasting lipids. It is unclear whether this also occurs in the daytime situation. Twenty-seven
normocholesterolemic, non-obese and nondiabetic patients with premature coronary artery disease
(CAD) and 56 first-degree relatives without CAD measured daytime capillary triglyceride profiles
(TGc-AUC) as an estimate of postprandial lipemia. Fasting capillary triglycerides (TGc) were not
significantly different between CAD index patients and their relatives (1.68 +/- 0.63 and 1.54 +/-
0.71 mmol/L, respectively). In contrast, daytime triglyceridemia was significantly higher in CAD
patients (30.7 +/- 13.6 mmol. h/L) compared to their relatives (24.4 +/- 9.4 mmol. h/L) and this
was also the case after correction for fasting TGc (7.24 +/- 7.41 and 2.79 +/-
6.89 mmol. h/L; P <.05). The best predictors of TGc-AUC by multiple regression analysis in CAD
families were fasting TGc, systolic blood pressure, and high-density lipoprotein cholesterol (HDL-
C), which are all components of the metabolic syndrome, explaining 65% of the variation. Since
there were no major differences in nutritional intake between index patients and their
relatives, this could not explain the differences Daytime triglyceridemia, measured under
physiological conditions, is increased in patients with premature atherosclerosis and normal
fasting TG levels, when compared to their non-CAD relatives. This study confirms previous
observations using standardized oral fat loading tests and underlines the importance of
postprandial hyperlipidemia in CAD.

(Jack Steele) said:

I have no medical training. Is the point that if not fasting increases triglycerides
significantly, there is a higher likelihood of CAD?

There appears to be a significant correlation with non-fasting trigs and premature atherosclerosis,
although the mechanism is not well understood. My perspective is that there is a significant
dysfunction somewhere in the liver, and niacin may indeed target this pathway as niacin not only
increases HDL, but also improves overall lipid metabolism in the liver and has beneficial properties
not yet fully understood.

--
Winning against heart attack and stroke sonoscore.comsonoscore.comOpen ↗

To clarify further, there is a unique "portal circulation" that is distinct from the standard
arterial and venous circulation system. The deoxygenated blood from the capillaries of the
gastrointestinal tract drains into the portal vein which, instead of going directly back to the
heart, leads to the liver. Blood from the liver drains via the hepatic veins into the inferior vena
cava which goes to the right side of the heart.

The liver is the recipient of the "first pass" effect with nutrients absorbed from the gut. This
allows the liver to take up the nutrients that were extracted by the intestines from food. The liver
also neutralizes some toxins taken up by the intestines. Obviously, a meal challenge, or oral fat
loading will first enter the liver and processed accordingly before reaching the hepatic vein,
inferior vena cava, heart and eventually the standard arterial beds such as the coronary and
cerebral arterial branches.

It in the "first pass" that I personally believe the benefit of nicotinic acid shines; it improves
the hepatic function lipid metabolic pathways and makes them more efficient.

Incidentally, estrogen, when administered in a transdermal patch will bypass the 'first pass', and
some experts believe transdermal estrogen is not as cardioprotective as oral estrogen which
undergoes 'first pass' modulation by the liver.

--
Winning against heart attack and stroke sonoscore.comsonoscore.comOpen ↗

Jack Steele said:

I have no medical training. Is the point that if not fasting increases triglycerides
significantly, there is a higher likelihood of CAD?

No. The point is that the test won't be accurate/repeatable.

Humbly,

Andrew

--
Dr. Andrew B. Chung, MD/PhD
Board-Certified Cardiologist
heartmdphd.comheartmdphd.comOpen ↗

Sonos said:

(Jack Steele) said:

I have no medical training. Is the point that if not fasting increases triglycerides
significantly, there is a higher likelihood of CAD?

There appears to be a significant correlation with non-fasting trigs and premature
atherosclerosis, although the mechanism is not well understood.

It's called over-eating.

The solution:

ask your doctor about heartmdphd.comwtloss.aspOpen ↗

Humbly,

Andrew

--
Dr. Andrew B. Chung, MD/PhD
Board-Certified Cardiologist
heartmdphd.comheartmdphd.comOpen ↗

On Fri, 9 Jan 2004 12:08:58 -0500, Dr. Andrew B. Chung, MD/PhD wrote
(in message <[email hidden]>😉:

Quoted message said:

Sonos said:

(Jack Steele) said:

I have no medical training. Is the point that if not fasting increases triglycerides
significantly, there is a higher likelihood of CAD?

There appears to be a significant correlation with non-fasting trigs and premature
atherosclerosis, although the mechanism is not well understood.

It's called over-eating.

The solution:

ask your doctor about heartmdphd.comwtloss.aspOpen ↗

Or, better yet, ask your doctor about the Two Foot Diet.

I developed the Two Foot Diet approach (2FD) as a replacement for Dr. Chung's Amazing Logic Defying
Two Pound Diet to avoid having to carry a scale around.

Inspired by Dr. Chung's scientific approach, as described on his website, in 2003, my wife and I
attended an IMAX film about climbing the Bavarian Alps and learned that despite their exhausting
regimen, the climbers consumed only 10 packages of wieners per week. That's less than 2 feet of
wieners per day! Since none of the climbers died from starvation, I think it is safe to assume that
2 feet of food per day should be more than adequate for us non-climbing folks.

So I started a little experiment with the agreeable obese friends in my neighborhood. I gave them
ordinary 6 inch rulers with instructions to measure the length of everything substantial that passed
into their mouths. The only things exempted were water and sugar-free drinks. What I learned was
that my obese friends were consuming between 8 to 12 feet of food per day! At the time, I was about
10 lbs. over my ideal body weight so I decided to find out how much I was eating per day... 3 feet.
I cut back to less than 2 feet and was at my proper weight in one month.

My friends have responded similarly except they have taken longer because of having to lose more
weight. Admittedly, some of my obese friends were especially slow to respond. They also happen to be
the ones with an unfortunate propensity for accidentally loosing their 6 inch rulers and taking
weeks to buy replacements.

So here's the deal: measure all the food you eat, using it's longest dimension, and keep the
total length to less than two feet per day. That's all there is. No scales, no counting calories
or carbohydrates. Heck, if you loose your ruler, you can even use the first joint of your thumb
to measure.

I am making this diet available as a public service and without compensation.

If you have any questions, just see Dr. Chung's helpful FAQ and substitute "Two Feet" for "Two
Pounds" everywhere... what could be simpler?

"If I have seen farther than others, it is because I have stood on the shoulders of midgets"

--
Steve

Weeding the Lord's Vineyards Since 2003

In article <[email hidden]>,

Dr. Andrew B. Chung said:

Quoted message said:

How does failing to fast before a cholestoral exam affect the results?

Can raise triglycerides an extraordinary amount.

Quoted message said:

Does it make them more noisy or skew them in a certain direction?

Elevated triglycerides can skew cholesterol measurements upwards.

So if one had borderline "high" trigs after fasting 14 hours, then one would have to assume that
during the regular course of a day when non-fasting the numbers would be much higher, yes?

(Jack Steele) said:

I have no medical training. Is the point that if not fasting increases triglycerides
significantly, there is a higher likelihood of CAD?

You might check out the recent thread on Garlic, but here is an interesting reference for
this thread...

The postprandial increase of triglycerides was clearly reduced under garlic medication as compared
to placebo treatment. This is a short term study; some studies indicate the favorable impact of
garlic can diminish with time.

Arzneimittelforschung. 1992 Oct;42(10):1223-7. [Postprandial lipemia under treatment with Allium
sativum. Controlled double-blind study of subjects with reduced HDL2-cholesterol]

[Article in German]

Rotzsch W, Richter V, Rassoul F, Walper A.

Institut fur Klinische Chemie und Laboratoriumsdiagnostik, Universitat Leipzig.

Postprandial Lipaemia under Treatment with Allium sativum/Controlled double-blind study in healthy
volunteers with reduced HDL2-cholesterol levels. The effectiveness of a standardized garlic powder
preparation (Sapec, Kwai) on alimentary hypertriglyceridaemia after intake of a standardized fatty
test meal containing 100 g butter was analyzed in a randomized placebo-controlled double-blind
study. 24 volunteers with HDL2-cholesterol concentrations in plasma of less than 10 mg/dl (men)
respectively 15 mg/dl (women) participated in the study. The volunteers received 3 times 1 tablet
daily over a period of 6 weeks equivalent to a daily dosage of 900 mg garlic powder in the active
treated group. Control measurements were made on the 1st, 22nd and 43rd day of treatment and 0, 3
and 5 h after intake of the meal. The postprandial increase of triglycerides was clearly reduced
under garlic medication as compared to placebo treatment. The determined AUC-values for the
triglycerides were up to 35% lower in the garlic group compared to the placebo group. The regular
intake of the garlic preparation over the period of 6 weeks showed a significant lowering of the
fasting values of triglycerides in comparison to placebo. Under garlic medication HDL2-cholesterol
increased more than under placebo in tendency.
--
Winning against heart attack and stroke sonoscore.comsonoscore.comOpen ↗

Owen Lowe said:

In article <[email hidden]>, "Dr. Andrew B. Chung, MD/PhD"

Quoted message said:

Quoted message said:

How does failing to fast before a cholestoral exam affect the results?

Can raise triglycerides an extraordinary amount.

Quoted message said:

Does it make them more noisy or skew them in a certain direction?

Elevated triglycerides can skew cholesterol measurements upwards.

So if one had borderline "high" trigs after fasting 14 hours, then one would have to assume that
during the regular course of a day when non-fasting the numbers would be much higher, yes?

Possibly.

Andrew

--
Dr. Andrew B. Chung, MD/PhD
Board-Certified Cardiologist
heartmdphd.comheartmdphd.comOpen ↗