A study conducted by researchers at the Duke Institute for Brain Sciences has revealed that women who show mild symptoms of cognitive impairment are at a greater risk of developing dementia faster, as compared to men with the same set of symptoms.

During the study, the Duke researchers analyzed the scores of 398 men and women who undertook a simple cognitive test. A majority of the participants were in their 70s. In addition to the cognitive tests, other tests such as PET scans were also performed on the subjects. The participants took the test continuously for four years, and some even continued to take the tests for eight years.

The researchers found that on average, the score for the women participants slipped by two points each year, as compared to a single point for men. The researchers considered factors that influence memory as control factors, including age, education and genetic predisposition.

“With any trial now, let’s say if you’re giving people a drug to see if it slows the rate of cognitive decline, you’re going to have to take account of this difference between men and women,” said Dr. Edward D. Huey of the Columbia University.

Among all the patients who suffer from dementia, the majority are women, in part because they live longer than men. Statistics reveal that of the 5.4 million sufferers in the United States, nearly 3.4 million are females. Researchers have long tried to find the reason behind the gender differences.

A previous study found that a woman's cognitive decline is facilitated after undergoing surgery under general anesthesia. Another study concluded that the accumulation of the protein that triggers Alzheimer's happens more in women's brains than in men's.