People with high cholesterol also have a worse risk of high blood pressure, U.S. researchers reported on Monday.
A study of 3,000 men followed for 14 years showed that those who developed the unhealthiest cholesterol levels raised their risk of hypertension by 39 percent.
“There appears to be a significant association between increased cholesterol levels and the risk of developing hypertension in healthy, middle aged men,” said Howard Sesso, an epidemiologist at Brigham and Women’s Hospital and Harvard Medical School in Boston.
“We looked at this same exact question in a study published a month ago in ... women. We found the same thing,” Sesso said in a telephone interview.
“Our findings suggest we may have a new means of preventing hypertension, a devastating public heath issue in this country.”
Both conditions are associated with atherosclerosis, or hardening of and damage to the arteries.
As many as 90 percent of U.S. adults with normal blood pressure at age 55 may develop hypertension in their lifetime. High blood pressure is one of the primary causes of heart disease -- the No. 1 killer of all Americans.
Unhealthy blood cholesterol is trickier to calculate as it involves several different readings -- high total cholesterol, high levels of low-density lipoprotein or “bad” cholesterol, and low levels of high-density lipoprotein or “good” cholesterol.
But the American Heart Association says nearly 107 million American adults have total blood cholesterol values of 200 or higher, and 37.7 million have levels of 240 or above. Cholesterol levels below 200 are considered desirable.
The risk factors for high blood pressure and high cholesterol are similar -- a diet rich in fat, low in whole grains, fruits and vegetables and a lack of exercise.
Sesso said it is not yet clear whether high cholesterol or high blood pressure develop at the same time, or whether unhealthy cholesterol levels in turn cause high blood pressure.
Direct association
But he said few studies had shown a direct association, such as this one, in people initially free of disease.
His team started with more than 3,000 men taking part in a larger study called the Physician’s Health Study. At the beginning all had healthy blood pressure and cholesterol levels.
Over the average of 14 years of follow-up, a third of the men developed high blood pressure, they report in this week’s issue of the journal Hypertension.
Men with the worst levels of bad cholesterol compared to good cholesterol had a 54 percent higher risk of high blood pressure compared to the mean with the healthiest levels.
Men with the highest levels of total cholesterol were 23 percent more likely to develop hypertension than men with the lowest levels. But men with the highest HDL or “good” cholesterol levels had a 32 percent lower risk of high blood pressure than those with the lowest HDL levels.
A second study, published in the journal Circulation, showed that total cholesterol levels have decreased in middle-aged to older adults but are rising among younger adults.
A survey of 5,000 adults in Minnesota over 20 years showed that drugs may be responsible.
“The older age groups use more lipid-lowering drugs. This may be partially responsible for the continued reduction of their total cholesterol,” said Donna Arnett of the University of Alabama at Birmingham, who led the study.
“Young men and women ages 25 to 34 have not shown any significant change in total cholesterol across the study, and in the past decade they have posted at least one significant increase on some part of the survey.”