Your guide to medical guidelines

After all she had heard and read recently in the news about differing opinions on cancer screening, my wife asked me: "What is wrong with you doctors? What is the public to do when the experts cannot make up their minds and do not agree with each other?"

Here is my attempt to explain.

Guidelines (that is what they are — guidelines, not rules, not laws, and not applicable to every person) are based on the population studies, which are observations, not experiments over a long period of time, like decades. The recommendations tend to change, depending on new observations and findings. Whenever the recommendations change, some of the old guard will try to resist, sometimes for justifiable reasons.

The government (even though it ends up getting the blame many times) does not control the findings and recommendations of the physicians and scientists, even though it may have contributed millions of dollars to support these studies.

Not long ago, the cardiology community, including the American Heart Association, recommended hormone replacement therapy with estrogen, as a protective measure for postmenopausal women. It seemed to make sense. Estrogen lowers cholesterol. Lower cholesterol reduces heart attacks. So estrogen must protect the heart like it does in menstruating women. After decades of population studies and spending millions of dollars, we realized that estrogen in postmenopausal women caused more harm than good by increasing the incidence of breast cancer and blood clots. So the recommendation changed.

Whether we like it or not, cost always comes into the picture, even in the days of the best economy. Any practicing physician can recall a number of anecdotal cases where a routine preoperative chest X-ray picked up lung cancer (in early stages, if the patient is lucky). But medical organizations including the American Cancer Society do not recommend routine chest X-ray as a screening measure, even in chronic smokers. Because it is not cost-effective in a public health perspective.

Prevention is sometimes confused with screening, especially in political debates. Screening involves a test to detect the existing disease in early stages. Prevention involves measures to prevent the development of a disease (primary prevention) and to halt the progression of the disease or prevent recurrence after initial treatment (secondary prevention), mostly by controlling risk factors, if possible.

Prevention is always cost-effective. Primordial prevention, which is preventing the development of risk factors that contribute to the origin of the disease, for example obesity and smoking, is the best and the most cost-effective.

Family history and advancing age are the common risk factors (for a lot of ailments) that one cannot change and one may not want to change. Good family history still remains the best and cheapest initial genetic test.

People always fear that the government and the insurance companies may misuse the new information and new recommendations especially as cost-cutting and money-saving measures. Also, the experts may go overboard at times, for example discouraging women from self-breast examination, as it may lead to unnecessary tests and unintended consequences.

Just as many people may feel relieved with the relaxed recommendations. Some of you may have hoped for new guidelines so that you do not have to do daily flossing or have a colonoscopy. But they will fall under prevention.

There is one guideline with which I strongly agree: Follow your personal physicians' personalized recommendations, depending on your individual situation. You have a personal physician you trust, don't you? If you do not have or cannot afford one, that is a whole different discussion.

Dr. Rao Musunuru, a practicing cardiologist, is a member of the Advisory Council for the National Heart, Lung, and Blood Institute at the National Institute of Health.