Obesity in middle-aged women has been linked with premature thickening of the carotid arteries in the neck, which supply blood to the brain, according to a report in the journal Stroke: Journal of the American Heart Association.

Premature thickening of these arteries is a sign of impending heart disease and a risk factor for stroke.

"There is an established link between obesity and damage to the heart, but whether obesity also has an independent effect on the carotid arteries is less well known," said Dr. Paolo Rubba, professor of internal medicine at Federico II University in Naples.

Researchers analyzed data from an ongoing study of chronic disease in more than 5,000 middle-aged women from Southern Italy. In this region, increased caloric intake, increased animal fat intake and sedentary habits have led to a high prevalence of overweight and obesity.

A sub-sample was taken of 310 study participants (average age 55) who had ultrasound testing to examine the thickness of the carotid artery. Researchers found a significant association between the estimates of obesity and the level of carotid artery wall thickness, which was still significant after accounting for other risk factors such as age, blood pressure and cholesterol levels.

A gradual increase in carotid artery thickness was found with increasing weight. Lean women had an average carotid artery thickness of .94 mm, overweight women had an average thickness of .98 mm and obese women had an average thickness of 1.02 mm.

Carotid artery wall thickness was higher for women with higher waist-to-hip ratios. Therefore, body mass index and waist-to-hip ratio were significant predictors of carotid wall thickness, independent of other risk factors, concluded the researchers.

"Controlling blood pressure is not enough to prevent the cardiovascular damage from being overweight," said Rubba. "Doctors should face the difficult challenge of encouraging patients to lose weight to prevent premature atherosclerosis (hardening of the arteries) and stroke. With the information in this study, women also should be aware of further health implications if they don't reduce their weight."

Researchers suggest that ultrasound screening in obese women may help identify those at high risk and those who may require aggressive therapy to prevent early atherosclerosis.

Further studies should focus on whether atherosclerosis in obese women progresses faster than in women who are not obese, advised Rubba.

Other sources: American Heart Association