Having high cholesterol in your 30s and 40s increases your risk for heart disease, and the longer it stays elevated, the greater the risk, a study reports.

Researchers studied 1,478 people, average age 55, who were free of cardiovascular disease. All had had their cholesterol levels measured periodically over the previous 20 years. The scientists followed the group for the next 15 years, during which 155 developed cardiovascular disease.

The study, published in Circulation, recorded how many years each of the subjects had had elevated cholesterol levels. (The researchers measured non-HDL cholesterol levels, or total cholesterol minus HDL, with a level of 160 or above considered high.)

The study found that cardiovascular disease rates increased 4.4 percent for those who never had elevated cholesterol, 8.1 percent for those who had it for one to 10 years, and 16.5 percent for those exposed for 11 to 20 years.

“The duration of exposure plays a role,” said the lead author, Dr. Ann Marie Navar-Boggan, a cardiology fellow at the Duke Clinical Research Institute. “Suppose you have two adults, both 55, same cholesterol, same blood pressure and so on, but one has had high cholesterol for one year and one for 11 years. The person who has had it for 11 years has a 39 percent increase in risk.”


Sugary drinks tied to menarche

Here is another mark against sugary drinks: A new study has found that drinking them is associated with lowered age of menarche.

Age of first menses has decreased substantially since the early 20th century, and studies have shown that younger age of menarche is associated with increased risk of breast and endometrial cancer in later life.

The study, published online in Human Reproduction, used data on 5,583 girls ages 9 to 14 who had not yet attained menarche at the start. After controlling for birth weight, maternal age at menarche, physical activity, and many dietary and behavioral factors, they found that girls who drank 1½ 12-ounce cans a day of nondiet soda or sugared iced tea had their first period an average of 2.7 months earlier than those who drank less than two cans a week.


It may feel better to pay more

Expensive drugs work better than cheap ones — or at least some people firmly believe they do.

Researchers told 12 patients with Parkinson’s disease that they were testing two drugs, one costing $100 and one $1,500 per dose. The drugs contained the same dose of the same medicine, they explained, but the manufacturing processes were different, and they wanted to see if they worked equally well. The study appears in the Feb. 24 issue of Neurology.

What the subjects did not know is that they all received an identical injection of a plain saline solution.

The “expensive” placebo worked significantly better, producing a twofold improvement compared with the “cheap” one. The effect was apparent not only in tests of physical ability, but also as measured by brain imaging. In fact, the effect of the expensive placebo was not significantly different from that of levodopa, the most effective medication for Parkinson’s disease. Levodopa acts by raising levels of the neurotransmitter dopamine in the brain.

“One of the reasons why the effect is so large is that it’s mediated by dopamine,” said the lead author, Dr. Alberto J. Espay, an associate professor of neurology at the University of Cincinnati. “We make more dopamine when we have heightened expectations of efficacy.”

When the subjects were told the true nature of the study, the researchers write, the reactions ranged from incredulity to astonishment.