Wednesday, November 18, 2009

Perhaps I shouldn't have been surprised by the emotional responses to the US Preventive Services Task Force new mammography guidelines for women age 40-49 released this week, but I have been taken aback by the incredulous tone taken by the mainstream media and even health professionals. A CNN interview today illustrates the dominant tone.

Thursday, November 5, 2009

Flu shots!

I took the kids (ages 10 and 2) for their flu shots today at the county fairgrounds. The line was a quarter-mile long, but it moved quickly. Luckily, the 2 year-old was eligible for the nasal spray, but my son (with asthma) got the needle. No one cried.

I was concerned, though, because I ran into a parent at school today who expressed some surprise that we were getting H1N1 shots. Apparently they were told by their pediatrician that the vaccine hadn't been properly tested. I tried to correct their impression, but I'm still surprised this was advice offered by a health professional. (I'm less surprised to hear the same claim while we were waiting in line today, by a couple who went on to suggest that President Obama was a terrorist, and that the authenticity of his birth certificate was in question.)

To debunk some vaccine myths:

1. The H1N1 vaccines were produced and tested in the same thorough fashion as each seasonal influenza vaccine has been every year
2. The vaccine is not mandated by the federal government
3. While the majority of people infected will recover without significant sequelae, a small number of people will become seriously ill, and--just as with the non-H1N1 seasonal flu infections--some will die. Young children and pregnant women appear to be at greater risk.
4. Vaccines that contain the preservative thimerosal (used in multi-dose vials) are safe.
5. The flu vaccine has not been associated with fatal reactions, or with serious problems like miscarriages or Guillain-Barre syndrome. Unfortunately, people will continue to have neurological disorders, heart attacks, and strokes, and by coincidence some of these may occur after a flu shot.

Get your shots!

Tuesday, October 20, 2009

Letter to the editor

I submitted the following to my local newspaper's editor this week. I've discussed it further in another post.

A letter in last week’s News (“Toothpaste a healthier cure”) included several inaccurate and misleading statements about the practice of fluoridating community drinking water. Since its inception, numerous studies have demonstrated fluoridation’s ability to reduce dental caries among children and adults. The letter writer quotes a Journal of the American Dental Association article that purportedly challenges the benefits of this practice, yet the paper’s authors concluded that evidence of fluoride exposure during enamel formation was indeed associated with fewer cavities. (The quote, it appears, is not actually from the JADA article, but from an anti-fluoridation group’s online press release.)

Despite allegations linking it to cancer, hip fractures, and decreased intelligence, there is no credible evidence associating fluoridated water with any significant health problems. While some of these myths may be more contemporary than the 1950s-era propaganda that stigmatized fluoridation as a Communist plot, they are equally egregious.

In the previous century our lives were greatly improved by several public health developments, among them improved sanitation, food safety, and family planning. Yet, these fundamental advances continue to be attacked. Tobacco companies reap huge profits from cigarette sales. Nearly 90% of U.S. counties lack access to abortion providers. Television personalities promote debunked theories about the dangers of childhood vaccines to concerned and credulous parents.

While these capitalists, crusaders, and conspiracy theorists may not share mutual affiliations, they profess a common philosophy that rejects the reasoned application of the scientific method. Organizations and journals with unassuming titles (e.g., Fluoride) espouse obscurant anti-intellectual agendas. These groups are not challenging the objectivity of science in the postmodern tradition—rather, they are simply relying on science done badly.

As a society, we’ve benefited from chlorinated water, seat belts, and the eradication of smallpox. As a society, we share the costs incurred by epidemic gun violence, influenza outbreaks, and shortages of dentists and family physicians. Healthy skepticism, rigorous scientific analysis, and open debates all have a role in collectively deciding what’s in the best interest of our health—profiteering, sophistry, and alarmism do not.

Fluoride: Helpful halogen ion or Communist threat?

I returned to my hometown last year after an absence of 16 years. It's a small college town of less than 4000 people, famously liberal, and replete with peaceniks, herbalists, and an impressive per capita ratio of both Ph.D.s and massage therapists. Growing up here, though, I was never aware it had attracted so many anti-vaccination adherents and other fringe theorists. An excerpt from one of last week's letters to the editor:

"Toothpaste a healthier cure"

An article recently published in the Journal of the American Dental Association found that 7- to 17-year-olds have "similar cavity rates in their permanent teeth whether their water supply is fluoridated or not."

I'm not a dentist or an epidemiologist, and had never seriously followed the debate surrounding community water fluoridation, but I was curious enough to do some fact-checking. The quoted article was co-authored by Jayanth Kumar, DDS, MPH, who is the director of the Oral Health Surveillance and Research program at the New York State Department of Health in Albany. The study is abstracted here.

I read and re-read the full text, but wasn't able to locate the letter writer's quote. Indeed, the authors didn't purport to disprove a connection between water fluoridation and the incidence of caries. Rather, it found an association between mild forms of fluorosis (tooth discoloration caused by fluoride exposure during enamel formation) and a decreased likelihood of cavities. Their study didn't attempt to answer the question of whether cavity rates are related to water fluoridation levels or not.

The quote, I later discovered, appears not to have been taken from the journal article itself, but from an online press release (JADA Study Proves Fluoridation is Money down the Drain) featuring the New York State Coalition Opposed to Fluoridation.

The group (whose president is an attorney) apparently recalculated and tabulated data from Kumar's study in order to compare community fluoride levels and cavity rates. There is no description of its methods, no statistical tests of comparison to help understand how the authors determined their data's significance, nor is their any acknowledgement that the table they include in their article was not taken from the study to which they refer. The letter-writer, too, fails to make such an acknowledgement, and continues:

Fluoride is not considered an essential nutrient because humans do not require it for growth or to sustain life. There is no known disease state associated with a deficiency of fluoride. So why are we still fluoridating our water?

It is true that fluoride is not an essential dietary nutrient, but tooth disease from dental caries is incontrovertibly linked to a lack of fluoride exposure. We are still fluoridating water supplies because there have been abundant data confirming decreased cavity rates in communities where fluoridation has been adopted.

One of the usual arguments in favor of fluoridation is the economic justice aspect where, as the argument goes, it would be unfair for those with meager financial means to be deprived of fluoridated water as they would be less likely to be able to afford dental care. But, if fluoride is not needed systemically and its ingestion is associated with more expensive medical care, the economic justice argument is without merit.

Despite my medical education, I was not aware of any major health problems associated with public water fluoridation. The author explains:

Fluoride is associated with dental fluorosis, skeletal fluorosis, joint pain, a lower IQ, reduced levels of circulating melatonin and earlier onset of puberty, hypothyroidism, an increased risk of mutation possibly leading to cancer, etc.

A review of the published literature confirmed that--except for dental fluorosis (tooth mottling)--there is no significant morbidity proven to be caused by water fluoridation. While high levels of endemic fluoride levels have been associated with skeletal fluorosis (for example, in India), there is no proven relationship between fluoridated water and an increased risk of fractures. Researchers who've claimed to have found associations between exposure to naturally occurring fluoride and decreased intelligence among groups of children in a sample of rural Chinese villages did not control for several confounding variables (including education level and nutritional status), making their conclusions suspect. (And, of course, difficult to extrapolate to the fluoridation program in my small Midwestern college town.) Lastly, there is simply no credible scientific evidence linking water fluoridation with increased risks of any type of cancer.

Why don't we take the money we as a village spend on this toxin and buy some toothpaste for distribution to the less fortunate? That way those who need some support have access to a safe method of delivery while those of us who wish to avoid ingesting poison can stop buying bottled water. It's time to critically analyze the practice of government-forced medication via fluoridation.

Of course toothpaste and other fluoride-containing dentifrices are critical to our dental health armamentarium. The consensus from dental and public health organizations, however, is that community water fluoridation--independently--remains a cost-effective means of reducing the burden of tooth decay. (The environmental risk-benefit ratio of purchasing bottled water to avoid drinking out of the tap is, at best, dubious.) The annual per-person cost of fluoridating public water supplies has been estimated to be approximately 50 cents (which, I guess, would buy a lot of toothpaste), yet the CDC has estimated that each dollar spent on this service saves $80.00 in dental bills.

I've since submitted a response to the editor, which I'll publish in a separate post. Unfortunately, I wasn't able to attend last week's debate in town between our county's public health commissioner and anti-fluoridation activist Paul Connett, Ph.D. If any attendees would like to comment on their experiences in the forum, I'd be grateful.