送交者: xj 于 2005-4-21, 00:30:32:
回答: 谢谢 由 更年期 于 2005-4-20, 17:01:32:
To keep in mind, blood pressure, cholesterol (total, LDL, HDL), and glucose are continuous variable. The cutpoint is arbitrarily determined based on population studies. The relative safe is an "on average" concept.
As a real example, recently American Diabetes Association revised the glucose criteria for diabetes and impaired fasting glucose (pre-diabetes). It changed pre-diabetes from above 110 mg/dL to above 100 mg/dL (based on fasting glucose, and should be less than 126 mg/dL) for Impaired fasting glucose. Similar changes were also made for oral glucose torrelance test. Therefore, those once "normal" people (who have fasting glucose 100-110 mg/dL) all of a sudden become abnormal.
Statistically speaking, when one look at disease distribution, the majority people who suffered heart diseases or stroke had only high normal blood pressure. For the same level of blood pressure (SBP 140 mmHg), one person is just fine but the other may develop stroke and heart disease.
Therefore,to many people, high normal is as risky as abnormal.
The population you belong to gives the probability of dying but your genes and lifestyle determine your fate.