The MDS Beacon™

A newly published research review concludes that smoking is associated with an increased risk of developing myelodysplastic syndromes (MDS).  The review also examines the potential impact of alcohol consumption on developing MDS, but finds no conclusive link between the two.

The review, carried out by researchers from the University of Pittsburgh, Amgen, the Cleveland Clinic, and SUNY Downstate, is a meta-analysis of data from ten independent studies carried out in Japan, Europe, and the United States.  The authors of the new review statistically combine the data from the ten previous studies to discern trends difficult to see in the small sample sizes of the previous studies.

The previous studies included male and female patients at least 18 years old.

All ten earlier studies examined the risk of smoking, and included a total of 1,839 people with MDS as well as 2,831 people without MDS (as controls).  In order to assess the link between smoking and developing MDS, the studies grouped ex-smokers and current smokers together in one group, and all others in a “non-smoking” group.

Based on their review, the authors of the new study estimate that smokers have a 45 percent higher likelihood of developing MDS than non-smokers.

This result “makes biological sense,” the authors write in their review.  Cigarettes are a common source of exposure to benzene, a hydrocarbon known to cause MDS.  In addition, tobacco products may cause chromosomal abnormalities, such as missing, extra, and malformed structures, or interchanged chromosome segments.  Genetic irregularities, such as deletions on chromosome 5 and 7, have already been established as risk factors for MDS.

The new study did not estimate a minimum smoking dose associated with MDS because not all of the independent studies reviewed in the study reported this factor.

Though the role of smoking in MDS is moderate compared to its association with other conditions such as lung cancer, the authors believe the risk is still important when considering the overall implications of smoking for public health.  Smoking has already been linked to MDS in separate studies, such as one conducted by the Yale School of Public Health and discussed in a previous MDS Beacon news article.

The authors of the new review also examined data from five of the ten previous studies, with a total of 745 patients and 1,642 controls, that examined the possible role of alcohol consumption in causing MDS.  Each study varied in how it grouped people for the purpose of comparing drinkers versus non-drinkers.

The review of the data from the five previous studies does not find support for a link between alcohol consumption and MDS.  The analysis shows a somewhat positive association between alcohol consumption and developing MDS, but the association is not strong enough to be statistically significant.

The authors note that previous research suggests that alcohol could be protective against MDS due to the antioxidant content of some alcoholic beverages, particularly red wine.  The new review, though, does not find support for such a link, but the authors acknowledge that more studies are needed to settle the role of alcohol consumption in MDS.

The authors also note that past research has established that major risk factors for MDS include age, male gender, exposure to hydrocarbons and other specific chemicals, and radiation.  However, they believe that further investigation of other possible causes, such as genetics, race, ethnicity, and lifestyle behaviors, is needed.

Similarly, the authors feel that further studies are needed to clarify to what extent the interaction of individual factors, such as smoking and alcohol consumption, may increase the risk of MDS.

The new study will be published in an upcoming issue of Leukemia Research (abstract).