Tuesday, July 19, 2011

Charleston Gazette Article Highlights Criticism of Conclusions of Kanawha County Heart Attack Study

An article in the Charleston Gazette highlights my criticism of the Kanawha County study which concluded that the county's smoking ban resulted in a sustained decline in heart attacks during the period 2000-2008.

Here are the details: Kanawha County (West Virginia) had virtually no clean indoor air protection in place until January 1, 2004. Prior to that time, smoking was allowed in most workplaces and in up to 50% of designated seating in restaurants. As of January 1, 2004, smoking was prohibited entirely in workplaces, including restaurants.The investigators examined hospital admission rates for acute coronary syndrome from 2000 through 2008, thus including four years prior to the smoking ban and four years following the smoking ban. Had the smoking ban led to a decline in acute coronary syndrome admissions, one would have seen such a decline during the 2004-2008 period compared to the 2000-2004 period.

The data, however, show no such decline. Instead, the data show a steady decline in acute coronary syndrome (ACS) rates that is consistent throughout the study period and does not accelerate after the implementation of the smoking ban. The study therefore demonstrates that a stringent smoking ban implemented in Kanawha County was not associated with any significant change in hospital admissions for acute coronary events, refuting the conclusions of other studies which reported such effects.

Curiously, this is not what the study authors chose to report in their conclusions. As if pulling a silver lining out of a dark cloud, the investigators instead conclude as follows: "In the presence of a CIAR [clean indoor air regulation], a consistent decline in incidence of hospital admissions for ACS can be demonstrated." The same conclusion is reiterated later in the paper: "In conclusion, our results demonstrate that from 2000 through 2008, the rate of hospital admissions for ACS has consistently declined in Kanawha County in the presence of an existing CIAR."

I argued that to associate the decline in ACS admission rates during this time period with the almost non-existent smoking restrictions is ludicrous. First of all, the paper does not show any change in the admission rate from before to after the weak county regulations. They had in fact been in effect since 1995. So unless the paper went back to about 1990, it could not possibly draw conclusions about the relationship between the county regulation passed in 1995 and any change in ACS admission rates.

Furthermore, the so-called clean indoor air regulation in the county is meaningless. Restaurants were allowed to designate up to 50% of their seating for smoking. That isn't a smoking ban. It's essentially no regulation. In almost every other study of this kind, such a regulation would be considered the absence of a smoking ban. Obviously, a 50% designated smoking area policy is not going to protect customers from secondhand smoke exposure. This has been proven in multiple studies.

I concluded that this story shows how seriously the quality of tobacco control science has degraded. I also offered a $100 reward to any anti-smoking group that had the integrity to report the actual study findings. Needless to say, there were no takers and my money remains safe.

The Rest of the Story

I think this article does a fine job of articulating this story and describing why it is that the conclusions of the study are unsupported by the actual study findings.

For example, the article astutely points out that: "The authors of the study do state in their findings that no significant changes were recorded "between, before and after the removal of smoking areas in restaurants," in 2004.

If this is the case, then how can the article possibly conclude that the smoking ban (which was implemented in 2004) led to a decline in the rate of acute coronary syndrome admissions?

The answer is: it can't. That it draws this conclusion anyway is essentially a sleight of hand. It is scientifically faulty at best and disingenuous at worst.

Not unexpectedly, for being willing to criticize anti-smoking research on scientific grounds, I was accused (in the comments section) of being a paid tobacco industry lobbyist. Well then, I guess I'll be excitedly anticipating the receipt of my next paycheck.

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