In-office stool tests may not be reliable for screening.
THE QUESTION Because polyps and tumors in the large intestine often bleed intermittently, blood in the stool can be a sign of cancer. How accurate are fecal occult blood tests, which check for hidden blood in the stool?
THIS STUDY involved 2,665 older people who had no symptoms of colorectal cancer. For each participant, a stool sample was collected during a doctor's office visit, and the person collected six samples at home. Colonoscopies subsequently given to each participant found 284 cases of cancer or large polyps considered likely to become cancerous. The single samples from the office visit had detected only 5 percent of these polyps or cancer, and the at-home samples had found 24 percent of them.
WHO MAY BE AFFECTED BY THESE FINDINGS? Anyone considering a fecal occult blood test.
CAVEATS About 98 percent of the participants were men; however, the authors said the findings should not differ by sex. The colonoscopies may have missed some polyps or cancers. The study was not randomized.
BOTTOM LINE People being screened for colorectal cancer should not rely solely on office or home stool tests; this study indicated those tests are inaccurate 95 percent and 76 percent of the time, respectively.
FIND THIS STUDY January issue of the Annals of Internal Medicine; abstract available online at www.annals.org.
LEARN MORE ABOUT colorectal cancer screening at www.cancer.org and www.cancer.gov.
Risk factors for heart disease may make dementia more likely.
THE QUESTION Sometimes the cause of dementia can be traced to a virus, depression or a neurological disease. Other times, it remains a mystery. Might factors that contribute to cardiovascular disease play a role?