Saturday, May 26, 2012

Weight Gain From Medication for High Blood Pressure

Weight gain from medication for high blood pressure is real. Of course,  many medications can increase weight. And sometimes there is no better drug so the doctor might have little choice but to prescribe a medication that might have weight gain as a side effect. 
But often there are alternative medications, better choices.

Blood pressure medications called beta blockers can cause weight gain.

And I think too often doctors prescribe beta blockers to treat high blood pressure. 
The medical term for high blood pressure is hypertension .

Weight gain is common with beta blockers. It may not be a lot of weight, on average, a little over 2 pounds. But with the obesity epidemic, gaining any weight is not what most of us want. 
Those of us adults with normal weight are in the minority now in the U.S..

There are many conditions for which beta blockers might be prescribed.
Hypertension is just one of those conditions.

Most recently, the clinical trial evidence indicates that beta blockers are not the best choice for hypertension in those without other reasons to use beta blockers like heart conditions such as angina, previous heart attack, irregular heart rhythm or heart failure. Beta blockers seem less effective than other drug classes at reducing strokes, heart attacks and heart failure especially in those over the age of 60.

In fact, the most recent expert guidelines from both Canada and United Kingdom do not recommend beta blockers as a first choice for so called uncomplicated hypertension.
The American Society of Hypertension agrees. Despite that, beta blockers such as metoprolol and atenolol are commonly prescribed by many doctors. 

Weight gain with beta blockers was shown years ago.
But doctors often overlook or seem to not be aware of weight gain from beta blockers. 
Beta blockers can cause other side effects too. 
And not all beta blockers are the same and some do not tend to increase weight, like carvedilol.

If you are struggling to control your weight and you take a beta blocker, ask your doctor if you could be safely switched to another type of medicine for your blood pressure. 
It might help a little with weight and maybe you would then be on a more effective agent.

Friday, May 18, 2012

Stop Kidney Stones

Stop Kidney Stones

You can take many steps to stop kidney stones?

If you know of someone who has had a kidney stone, that's no surprise.
Each year almost half a million people visit emergency rooms because of kidney stones.
What is surprising is how few people do anything to stop kidney stones once they have had one.

There are simple steps to stop kidney stones or reduce kidney stones besides just drinking more water. 

Drinking a minimum of 2 quarts of fluid intake daily is advised. This can be tea, coffee or other beverages like water.

Not all kidney stones are the same.
But most kidney stones are composed of calcium oxalate.
Recently, this type of kidney stone has been shown to be more frequent after surgery for obesity. That fact is often overlooked by bariatric surgeons.

How does a person who has had calcium oxalate stones know what to do to stop kidney stones? This is where analysis of 24 hour urine collections provides crucial information. 
I discussed this in a previous post.

Dietary changes and medication both can be very helpful to stop kidney stones.

Kidney stone prevention is often not addressed by urologists who treat stones.
Prevention is always better than waiting for the next stone to appear and cause more pain and suffering.

Although many endocrinologists are not interested or skilled in kidney stone prevention, in our practice we have knowledge and an interest in kidney stone prevention. 
After all, stones, like osteoporosis, are related to mineral metabolism.
And endocrinologists are specialists in hormones and metabolism.

When we try to help our patients stop kidney stones, we always start with dietary changes and encourage our patients to continue those dietary changes over time.

And what is one dietary change you do not want to make if you have had calcium oxalate stones?
Cutting down on your dairy intake to reduce your calcium intake.
It turns out, that taking in less calcium from the diet may actually increase your chances of more stones.
One reason for this is that with less calcium intake you tend to absorb more oxalate.
A recent study showed that supplementing with vitamin D in stone formers with low vitamin D levels appears to be safe.

Reducing your intake of sodium and oxalate are useful measures to help stop kidney stones. But what foods are high in oxalate? This can be confusing to many.

Nuts and spinach are high in oxalate. Lists of oxalate content of foods are now available from a variety of sources

Rarely, some people have a very high urinary excretion of oxalate and are more likely to get not just calcium oxalate stones but also kidney failure. This disease called primary hyperoxaluria can be missed if the doctor is not aware of it. 
In normal people, urinary oxalate should be below 40 milligrams in 24 hours. 
In those with primary hyperoxaluria urinary oxalate is usually above 100 millgrams in 24 hours.

A recent short term study suggests that fish oil supplements may reduce urinary oxalate. These findings remain preliminary.

In the common cases of calcium oxalate stones, dietary measures are often not enough. Medication is usually necessary to stop kidney stones.
Fortunately, safe, simple, low cost medications are often available.

In our practice, we tailor both diet and medication to the individual.
Our goal is reduce the suffering and expense caused by kidney stones. 

Saturday, May 12, 2012

Airport Scanner Risks

Do airport scanners pose risks?
Just how safe are airport scanners?
Have airport scanner risks been well studied?

There are two main types of airport scanners used in whole body imaging of passengers.
One type is the millimeter-wave scanner like ProVision. These scanners probably pose less of concern because they do not use x-rays but as stated in a recent analysis by radiation expert Dr. John Moulder: "information on the millimeter-wave scanner is very difficult to find".
Millimeter wave scanners use radio-waves similar to a microwave.

On the other hand, there are definite risks with the other scanners which are called x-ray backscatter scanners.

The amount of radiation delivered during a backscatter airport scan is estimated to be very low: about 1 microsievert.
A Sievert is a measure of energy from radiation.

The huge federal bureaucracy called the Transportation Safety Administration (TSA) claims that the amount of radiation a person is exposed to during x-ray scanning is less than what one would get from background radiation during less than 10 minutes of flight in the airplane.

As Dr. Moulder states, "this assumes that the machines cannot malfunction or be misused in ways that substantially increase the power density". That concern holds for both types of scanners.

And there remain many other possible risks from airport scanners that use x-ray backscatter.

First is the fact that there are no long-term studies of repeated exposure to these doses of radiation. The radiation in these backscatter scanners is said to concentrate in the superficial tissues like skin. But as stated in a recent paper “there is no accepted mathematical model for understanding the relationship between skin exposure and risk of skin cancers”.

In addition despite the presumed concentration in skin, there is some penetration of the x-rays through the body. That’s why bones are seen on many images like in the one below.
Physicist Dr. Leon Kaufman points out that “far more x-rays are stopped deep in the body or go through it than 'bounce' off the skin”. As shown below:

Radiation expert Dr. Paul Brenner states that : “despite much research into this key topic, a definitive cancer risk estimate …remains elusive” 

All x-ray devices must be properly maintained and serviced. Even if the scanners are 99.9 % reliable, there would still be many people put at risk if hundreds of millions of scans are performed with 0.1 % failure. And with equipment malfunction people might be overexposed to the x-rays.

At this time there are about 800 million commercial passengers getting on planes each year in the U.S.
Dr. David Brenner points out the risk to the population as opposed to the individual.

Let’s say, the individual risk of causing cancer from x-ray backscatter scanners is one in 10 million. When almost 1 billion people in the U.S. each year are exposed to this technology, some cancers are very likely to occur just because of so many people being exposed.
That reality has led the European Union to ban scanners that use x-rays.

Dr. Kaufman and others believe this use of x-ray backscatter scanners is a “mass experiment … the results of which will not be known” for years. A general medical principle is first, do no harm. And when it comes to x-rays, the comparable principle is to use as low as reasonably achievable (ALARA) exposure.

And  Dr. Moulder writes, there has been no independent review or regulation of these scanners and although "all other x-ray systems in the U.S. are regulated and inspected by state radiation protection agencies. The TSA has somehow exempted themselves from such oversight and appears to be ignoring widely-accepted radiation safety practices".

Millimeter-wave scanners do not use ionized radiation like the x-ray backscatter scanners.
But the risks of millimeter-wave scanners remain unclear.

Aside from safety, there is no evidence that scanning of passengers prevents terrorist acts.
In fact, there are ways of avoiding detection of weapons on the scanners. 
Israeli airport security has not implemented this scanning technology, pointing out its deficiencies.
Take a look at this excellent presentation.  

And you may find this very interesting.

Despite airport scanner risks and failings, there have been monetary forces that played a role in forcing this technology upon the public. Former head of the U.S. Department of Homeland Security Michael Chertoff is one who has clearly profited. And despite promises to conduct more studies, the TSA has failed to do so.

That's my analysis of airport scanner risks.

As long as I can, I will choose to “opt out” and not be imaged.

Saturday, May 5, 2012

Astaxanthin Claims

Recently astaxanthin claims abound. There are a bunch of products sold that contain astaxanthin. They use such names like “ageless male” and Hawaiian astaxanthin. Those selling these products on the web or television make claims that their particular product with astaxanthin “provides protection for all of our cells”, prevents cataracts and much more.
It sounds like if you take astaxanthin you will stop aging, increase your testosterone and maybe not die.
And if you combine astaxanthin with saw palmetto extract, wow!
Who knows what might happen?

Is there scientific basis for any of these astaxanthin claims?
And what is astaxanthin?

Astaxanthin is a carotenoid chemically related to lycopene, lutein and beta carotene. Astaxanthin gives salmon and shrimp their reddish color.
Astaxanthin is commercially obtained from microalgae and shrimp shells.
Did you know that beta carotene was shown to increase cancer and deaths when given to male smokers?
The chemical structure of beta carotene and astaxanthin have much in common. 
See the chemical structures below. 

Beta Carotene 


Astaxanthin has anti-oxidant properties  but if you have read my post on anti-oxidants you would be very skeptical in general of taking pills that are so called anti-oxidants.

Should we try to outsmart our body by taking these presumed anti-oxidants, interfering with our natural pro- versus anti-oxidant balance?
And what happens when we do that especially if astaxanthin has anti-oxidant properties?

But really are there double blind placebo controlled trials that show that astaxanthin does anything good?
And has astaxanthin been shown to increase testosterone in placebo controlled trials?

Let me answer the last question first.

There was one open label study done in Cameroon.
And in case your geography is a bit weak, Cameroon is in Africa.
Cameroon is not exactly a hotbed for clinical research studies.

The supplement manufacturer was a co-author of that study conducted in Cameroon.
The study was done in 42 healthy men. That means these men did not have a low testosterone to begin with. 

This trial had no control group and used astaxanthin combined with a  saw palmetto supplement. The authors claimed that testosterone increased within 3 days using this supplement. That result is physiologically implausible and impossible to interpret without a placebo or control group. This is a dubious publication of poor quality done by someone with a clear conflict of interest.

And there are no other studies published in peer reviewed journals that show that astaxanthin increases testosterone levels.

As for saw palmetto, take a look at my post on saw palmetto.

How about studies showing slowing of aging with astaxanthin?
Nope, nothing.
Okay how about any randomized controlled clinical trials with astaxanthin?

In one of the best trials, 14 competitive cyclists showed better performance with 3 milligrams of astaxanthin as compared to placebo. On the other hand, in another study, muscle soreness and muscle injury were no different with astaxanthin supplementation as compared to placebo in resistance trained men.

Is astaxanthin safe?
A study with 6 milligrams of astaxanthin showed no problems but that study only lasted 8 weeks.
There are no long term trials evaluating the safety of astaxanthin. 
Astaxanthin may not affect blood clotting but that study was done with a synthetic astaxanthin.

Reductions of 25 percent in serum triglycerides and increases of 10 percent in HDL cholesterol have been seen with astaxanthin at a 12 milligram daily dose. But at the  18 milligram dose of astaxanthin , no change was seen in HDL cholesterol.  Strange that the lower dose "worked better" at least on HDL cholesterol.
The subjects studied were healthy Japanese adults with triglycerides averaging 150 mg/dl.,  a level fairly close to normal.

One study of 30 infertile men showed a beneficial effect on sperm parameters and fertility.

So astaxanthin shows some promise but most of those astaxanthin claims on testosterone, aging and more are without scientific merit.
More studies of astaxanthin safety and possible benefits need to be conducted. 

You might say that the main “ageless” attribute of astaxanthin is this:
hucksterism and scams are very much alive and well and will be forever, sadly even amongst some of the medical profession.