Metabolic syndrome predicts a worsening of intima-media thickness in the carotid artery of elderly women, according to findings from a 12-year population-based study.
Maija Hassinen and her colleagues at the Kuopio Research Institute of Exercise Medicine in Finland randomly selected 299 women, aged 50–60 years, from a large risk-factor survey. The women were followed from 1982 to 2003, at which point complete data were available on 101 women, who were then aged 70–80 years.
Patients were considered to have metabolic syndrome if they met at least three of the following criteria from the National Cholesterol Education Program: high blood pressure (130/85 mm Hg or greater, and/or drug treatment), high blood glucose levels (110 mg/dL or greater), HDL cholesterol levels less than 50 mg/dL, triglycerides of at least 150 mg/dL, and a waist circumference greater than 88 cm.
The women had an average of 1.5 risk factors for metabolic syndrome at baseline. Of the 13 women with metabolic syndrome at baseline, their mean carotid intima-media thickness (IMT) was 18% greater than in those without metabolic syndrome (1.21 mm vs. 1.03 mm), said Ms. Hassinen and colleagues (Arch. Intern. Med. 2006;166:444–9).
By the end of the study all participants had an average of 2.3 metabolic risk factors, and 46% had metabolic syndrome. For all participants, waist circumference increased by 10%, body mass index increased by 2%, and glucose levels rose by 11% over the 12-year period. Additionally, their levels for LDL cholesterol dropped by 16%, HDL cholesterol decreased by 21%, and systolic and diastolic blood pressure levels decreased by 8% and 19%, respectively. The use of medications for hypercholesterolemia rose from 7% to 36%, and for hypertension from 23% to 56%. The mean carotid IMT for participants rose from 1.05 mm to 1.27 mm, for a 21% increase.
Of the 88 women who did not have metabolic syndrome at baseline, 34 had developed incident metabolic syndrome. After adjusting for factors such as age, prevalent cardiovascular disease, physical activity, smoking, LDL cholesterol levels, carotid IMT, and a baseline National Cholesterol Education Program score for metabolic risk, the mean carotid IMT in these 34 women was two times greater than it was for the 54 women without incident metabolic syndrome. Furthermore, “the more metabolic risk factors that occurred during the 12-year period, the greater the increase in the mean carotid IMT,” said Ms. Hassinen and her colleagues.
The researchers concluded that “incident metabolic syndrome and the increasing number of metabolic risk factors [were] able to predict the progression of carotid IMT in elderly women,” and thus provide “additional information regarding the progression of preclinical atherosclerosis beyond conventional risk factors and can therefore improve the prediction of clinical [cardiovascular disease].”
Because of the rapidly growing elderly population in many Western countries, “carefully planned health promotion programs and treatments for the metabolic syndrome are urgently needed,” they concluded.