Flush in the face = Give up the bottle?

June 13, 2009 9:12 AM

A somewhat recent NY Times article explains the connection between ALDH2 deficiency and throat cancer. Request for perspective on level of risk and appropriate response in extended.

The article explains that people who become flush in the face after drinking are likely to be ALDH2-deficient, and are thus at higher risk for throat cancer.

But it is also possible for an ALDH2-deficient person to develop tolerance to the flushing effect, such that no flushing appears.

Questions:

1. If a person suspects that he or she belongs to the population just described (ALDH2-deficient with no signs of flushing), will the patch test (applying an ethanol-soaked patch to the skin for 15 minutes) described in the article be of any use? Could such a test be performed and interpreted by a non-professional at home, and if so, how?

2. Even if the risk of throat cancer is increased through drinking, is that enough cause to seriously curtail one's drinking, or even abstain altogether? What is the prevalence of throat cancer in the general population?

3. Is the risk increased significantly if the person is a former smoker (i.e. having quit)?

4. Are there any measures one might take to lower his risk, besides limiting his or her drinking?

posted by Busoni to health & fitness (4 comments total)

From another article (I didn't want to log in for the NYT article) Researchers say studies in Japan and Taiwan show that people who consistently experience a red face after drinking alcohol have an increased risk of developing alcohol-related esophageal cancer, even if they are only moderate drinkers. Some studies suggest the risk may be up to 18 times greater, with heavy drinkers facing the biggest risk.

Without the deficiency, smoking and drinking increases your risk for head and neck cancer by 100x. Drinking OR smoking both increase your risk, but with smoking and drinking combined the risk is multiplied. This is for head and neck cancers in general. However, the article I found (don't know if the NYT article also was this) was on the link between the ALDH2 deficiency and the risk of esophageal cancer specifically, so for other head/neck cancers, it could be different. The information I found doesn't address former smokers' risk, and that's kind of a harder thing to quantify. Assessing their risk would probably have to be based on how much that person smoked, and for how long.

It seems to me that the only way to reduce risk is to limit their alcohol intake, the same thing anyone concerned about alcohol as a risk factor for throat cancers would have to do.
posted by ishotjr at 9:31 AM on June 13

Really, you're wading right into the future of medicine here. Identifying risk factors and modifying your behavior to prevent a disease is a relatively new concept, and one that the medical profession is still trying to figure out. We're discovering all of these risk factors, but still lack an understanding of how these complex factors interact with each other to result in an individual getting a specific disease.

Some of it is undoubtedly due to chance, but some of it is within our control, and specialists need to learn how to interpret these findings and make solid recommendations to folks like you, who are in a slightly higher risk group. (sidenote: If you're looking for a career, and don't mind lots of education, genetic counselors are going to be in huge demand over the next decade).

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1. If a person suspects that he or she belongs to the population just described (ALDH2-deficient with no signs of flushing), will the patch test (applying an ethanol-soaked patch to the skin for 15 minutes) described in the article be of any use?

According to the article, the survey alone is quite effective, with 90% sensitivity and 88% specificity:

(A) Do you have a tendency to develop facial flushing immediately after drinking a glass (about 180 ml) of beer?; (B) Did you have a tendency to develop facial flushing immediately after drinking a glass of beer in the first one or two years after you started drinking?

If the answer to either is yes, then you're very likely to have ALDH2 deficiency. If I'm reading the article right, the high-risk group is largely composed of those who flushed at first, but built up tolerance. (If you never built up tolerance, the flushing reaction makes drinking too unpleasant, and you generally stop drinking on your own). A patch test could provide a little more confirmation, but if you've never flushed from drinking, you probably won't flush there either. This test seems largely unnecessary to me, especially given the actual risk involved (more below)

2. Even if the risk of throat cancer is increased through drinking, is that enough cause to seriously curtail one's drinking, or even abstain altogether? What is the prevalence of throat cancer in the general population?

In order to umake an informed decision about behavior modification, you first need to understand what the actual risk is. According to Wikipedia, the NCI estimated about 15,560 cases of esophageal cancer would be diagnosed in the US. That's only 0.005% of the population. So, statistically, your overall risk is low to begin with. They also state that if you're a flusher, your relative hazard is about 12 times higher. 12 times very small is still pretty small.

Of course, you have to weigh the small risk against the fact that after diagnosis, the 5-year survival rate is only about 5%. It's usually found as a late-stage cancer and gets pretty ugly.

3. Is the risk increased significantly if the person is a former smoker (i.e. having quit)?

A history of regular smoking means that your cells were exposed to carcinogens for as long as you smoked. This undoubtedly has caused a few mutations in your DNA and increases your risk for several types of cancer. How much your risk increases depends entirely on how long you smoked, how heavily you smoked, etc. There are many papers on cancer and smoking - you can do some research yourself. That said, it's great that you no longer smoke, and it means you're at lower risk than someone who still does.

4. Are there any measures one might take to lower his risk, besides limiting his or her drinking?

Sure. The National Cancer Institute has great resources on cancer prevention. Here's the one for esophageal cancer, which includes things like reducing smoking and alcohol consumption, eating a better diet, and reducing the use of NSAIDs.


Bottom-line: I'm not a doctor, I can't dispense medical advice, but if this were me, I'd cut back on alcohol, and make sure that I didn't start smoking again. The relatively small risk probably wouldn't be enough to make me stop drinking altogether, but I might have 2 beers instead of 3 some nights, or start having something besides beer with my meals every evening. I mean, hell, less booze is less calories, and reduces your risk for all sorts of problems later in life. Why not cut back a little? The same goes for diet - eating healthier lowers your risk for all sorts of cancers, obesity, diabetes, etc. Given that there's practically no downside, why not work a few more veggies onto your plate?
posted by chrisamiller at 10:37 AM on June 13 [2 favorites has favorites]

1) Probably not. The original paper only mentions patch-testing "young people with little experience of alcohol consumption." According to this review paper, there's some disagreement about how good the test is. One study in Japanese youths said it's great, but four others showed worse reliability "...suggesting that ageing and acquired tolerance to acetaldehydemia influence the test results. In addition, the ethanol patch test in persons with both ALDH2*1/2*2 and ADH2*1/2*1 usually shows false-negative results."

This means that as people get older and more used to alcohol, the same tolerance that stops people from flushing will also stop them from reacting to the patch test. The authors conclude that in adults the patch test is less effective than the "flushing survey", i.e. just asking people if they do or used to flush after drinking.

2) The papers only give odds ratios ("you're x times more likely than...") not absolute numbers. It's actually very hard to get good data for that. Note that the American Cancer Society's figures of 16,470 new cases in 2009 or a 1/200 lifetime risk aren't that useful here. These are averages across the whole population, so someone who doesn't drink and has never smoked has a much lower chance than this but someone who does drink and does (or used to) smoke has a much higher chance.

Practically all oesophogeal cancers occur after the age of 45. So if you're not too far over 45 you can get a rough estimate by starting with the average lifetime risk (1/200) and multiply it by 12 to see the what the risk would be if you're deficient for the gene and you continue drinking heavily for the rest of your life.

3) I can't answer this directly, but:
(a) Alcohol and smoking have a synergistic effect on oesophogeal cancer, i.e. [risk from smoking and drinking] is bigger than [risk from just smoking] + [risk from just drinking] (e.g. See graph here)

(b) The risk of oesophogeal cancer decreases quickly when you've stopped smoking (to 60% after 5 years) but will never return completely to the levels of someone who's never smoked: you remain about 2.4 times more likely to develop the cancer than someone who's never smoked. (ref: Discussion, 3rd paragraph)

The lasting after-effects of smoking have left behind a population of damaged cells. These aren't cancerous (unless you're particularly unlucky) but they've sustained damage that makes it easier for them to become cancerous later. So while I couldn't find a study on ex-smokers + alcohol, what I know about carcinogenesis suggests that an ex-smoker will be at a higher risk from alcohol consumption than a never-smoker.

4) After drinking and smoking, the biggest risk factor seems to be diet. Eat plenty of fruit and vegetables, try to avoid cured/pickled meats, and don't get obese. One study that I skimmed and closed before copying the reference (sorry) mentioned a link with drinking hot, strong alcohol so, um, try to avoid making tea with vodka?
posted by metaBugs at 1:10 PM on June 13

Oh yes: I'm a biologist, but NOT a doctor or any kind of medic.
posted by metaBugs at 1:12 PM on June 13