Posted: April 4, 2016

A recent article in PLOS ONE (click here for link) is a large meta-analysis of several studies that purport to show that mortality from three common cancers — breast colon and prostate — is reduced if the person so affected takes low-dose aspirin as part of overall health maintenance.  To review information that may not be known to our readership, low-dose aspirin is thought to reduce mortality from heart disease and stroke, and is likely as well to prevent colon polyps, the precursor lesion to most colon cancers.  81 mg/day of aspirin is the usual dose (1/4 of an adult aspirin tablet, available as and 81 mg tablet widely) although that has not been entirely standardized.   The prevention of colon cancer has been generally accepted, but the ability of low-dose aspirin to reduce mortality in people who already have cancer is new information.  The power of the study is in the large number of studies they reviewed.  As with all meta-analyses, no new data were presented.  The authors did not reveal whether they went back to all the studies they reviewed to tease out original data for re-evaluation or whether they took the authors’ conclusions at face value.   In any event, the overall reduction in mortality was substantial, at between 10 and 20%.   Dr. Stark comments, “As with all meta-analyses, the reader is at the mercy of the statisticians who allege they know what they are doing.  The highest quality metas go back and pull raw data from the original trials.  There is no evidence that this happened here.  Furthermore PLOS ONE is peer reviewed but not as rigorously as the more established journals, and the authors pay to have their paper published, likely a reflection of having been turned down by the more established, prestigious journals.  Nonetheless,the authors give all of us one more reason to take that 80 mg of aspirin every day.”