A general purpose, current generation helical CT scanner equipped for retrospective cardiac gating can accurately quantify coronary calcium, and the results are highly correlated to scores obtained with electron beam CT. As an alternative method for measuring coronary calcium, gated subsecond cardiac helical CT offers greater availability and lower cost, thereby making population-based screening for coronary artery calcium more feasible.

Background High blood pressure in middle age is a well-established risk factor for cardiovascular disease, but the consequences of low-level elevations during young adulthood are unknown. Objective To measure the association between prehypertension exposure before age 35 and coronary calcium later in life Design Prospective cohort study Setting Four U.S. communities Participants Black and white men and women recruited at age 18–30 for the Coronary Artery Risk Development in Young Adults (CARDIA) Study in 1985–6, and without hypertension before age 35 Measurements We estimated blood pressure trajectories for each participant using measurements from 7 examinations over the course of 20 years. Cumulative exposure to blood pressure in the prehypertension range (systolic 120–139 and/or diastolic 80–89 mmHg) from age 20–35 was calculated in units of “mmHg-years” (similar to “pack-years” of tobacco exposure) and related to presence of coronary calcium measured at each participant’s last examination (age 44±4). Results Among 3560 participants, the 635 (18%) who developed prehypertension before age 35 were more often black, male, overweight and of lower socioeconomic status. Exposure to prehypertension before age 35, especially systolic prehypertension, showed a graded association with coronary calcium later in life (coronary calcium prevalence 15%, 24% and 38% for 0, 1–30, and >30 mmHg-years of exposure, respectively, p<.001). This association remained strong after adjusting for blood pressure elevation after age 35 and other coronary risk factors and participant characteristics. Limitations Coronary calcium, though a strong predictor of future coronary heart disease, is not a clinical outcome. Conclusions Prehypertension during young adulthood is common and associated with coronary atherosclerosis 20 years later. Keeping systolic pressure below 120 mmHg before age 35 may provide important health benefits later in life.