It's difficult for doctors to predict who is at risk for a serious clot. Simply looking at blood clotting tests like an increased prothrombin time (PT), an increased INR level, or a low platelet count cannot assure us of a low risk of serious clots. We once thought people with cirrhosis/end-stage liver disease were "auto-coagulated" (i.e. - protected against clots as though they were on a blood thinner like Coumadin), but as you've seen in your friend's situation, that's not the case. One last thing: an undetected cancer somewhere in the body can trigger pro-clotting proteins that cause abnormal clots. Always consider that in the setting of an unexplained blood clot.
Q: I've been hearing a lot about the U.S. Preventive Services Task Force making recommendations about the need for things like PSA blood tests and mammograms under a certain age. Who are they and what is their agenda?
A: The task force is a quasi-governmental group of 16 experts in preventive and evidence-based medicine that operates under the auspices of the federal Agency for Healthcare Research and Quality. Their "good versus harmful," cost-conscious agenda is to make evidence-based recommendations on whether there's a need or benefit to many of the common clinical preventive services performed by doctors in the United States.
A number of their recommendations have been controversial, and the panel has been criticized for reaching conclusions without sufficient input from specialty societies (for example, the American College of Radiology or the American Urological Association) or established experts in each field.
While they have made a number of good recommendations, some of their controversial recommendations include: (1) No routine screening for colorectal cancer for people over the age of 75; (2) No screening for testicular cancer in adolescents and adult males; (3) No PSA screening for prostate cancer; (4) No mammograms until age 50; (5) No routine use of aspirin to prevent colorectal cancer; (6) No routine EKGs in asymptomatic people, and insufficient evidence to recommend for or against routine EKGs in people at high cardiovascular risk; (7) Insufficient evidence to recommend for or against routine screening for glaucoma; (8) Insufficient evidence to recommend for or against routine screening for thyroid disease in adults; (9) No routine screening for peripheral arterial disease; and (10) No value in teaching patients how to do a self-breast examination.
Mitchell Hecht is a physician specializing in internal medicine. Send questions to him at: "Ask Dr. H," Box 767787, Atlanta, Ga. 30076. Due to the large volume of mail received, personal replies are not possible.