Longitudinal paths to the metabolic syndrome: can the incidence of the metabolic syndrome be predicted? The Baltimore Longitudinal Study of Aging.

OBJECTIVE To determine the predictors of incidence of metabolic syndrome (MetS) (Adult Treatment Panel III criteria) and to determine if longitudinal changes in specific MetS components differ by age or gender in participants who developed versus those who did not develop MetS. METHODS A total of 506 men and 461 women (baseline age 52.4 +/- 17.5 years) from the Baltimore Longitudinal Study on Aging (BLSA) were followed longitudinally (at least two study visits), and censored when they developed the MetS or reported use of antihypertensive or lipid-lowering medications. RESULTS After a follow-up period of 6 years, the incidence of the MetS was 25.5% in men and 14.8% in women. As many as 66% of men and 73% of women with one or two altered MetS components at baseline did not develop the MetS. Predictors of developing MetS were higher baseline abdominal obesity or triglycerides and lower high-density lipoprotein cholesterol (area under receiver-operated curve [AUC] = 0.84 in men, 0.88 in women). Addition of the rate of changes in MetS components over time slightly improved predictive accuracy (AUC = 0.94 in men, 0.92 in women). Men were more likely than women to have the MetS without obesity, whereas women were more likely than men to have the MetS without an altered glucose metabolism. CONCLUSIONS The patterns of MetS components and the longitudinal changes that lead to the MetS are different in men and women. Interestingly, components with the highest prevalence prior to MetS development, such as elevated blood pressure, are not necessarily the stronger risk factors.