Community-based studies have evaluated cross-sectional age relations of aortic stiffness measures, which are not often recapitulated in longitudinal studies. We examined baseline and longitudinal change in aortic stiffness in 5491 participants (mean age, 49.5±14.5 years; 54% women) who attended 2 sequential examinations (6.0±0.6 years apart) of the Framingham Heart Study. Cross-sectional relations of central hemodynamics (mean arterial pressure, central pulse pressure, carotid-femoral pulse wave velocity, and characteristic impedance) with age and risk factors were assessed at visits 1 and 2 (models 1 and 2). We used model 1 coefficients (M
1
), visit 1 risk factor levels (R
1
), and age at each visit (A
1
, A
2
) to estimate values at visits 1 (M
1
R
1
A
1
) and 2 (M
1
R
1
A
2
). While using model 1 coefficients, we accounted for age and risk factor level (R
2
) changes to predict values at visit 2 (M
1
R
2
A
2
). Using model 2 coefficients (M
2
) and visit 2 age and risk factor levels, we predicted visit 2 values (M
2
R
2
A
2
). We calculated predicted change 3 ways: delta1=M
1
R
1
A
2
−M
1
R
1
A
1
, delta2=M
1
R
2
A
2
−M
1
R
1
A
1
, and delta3=M
2
R
2
A
2
−M
1
R
1
A
1
. Delta1 values were biased and correlated poorly with actual changes (
r
=−0.02–0.14). For mean arterial pressure, delta1=1.9±0.8 mm Hg (
r
=0.14), observed change=−3.3±10.3 mm Hg, and discrepancy=5.2±10.2 mm Hg (
P
<0.0001). For characteristic impedance, delta1=7.2±14.7 dyne×sec/cm
5
(
r
=0.07), observed change=20.5±68.2 dyne×sec/cm
5
, and discrepancy=−13.3±68.7 dyne×sec/cm
5
(
P
<0.0001). Delta2 values were moderately correlated with change (
r
=0.17–0.54) but remained biased whereas delta3 values were moderately correlated with change with no bias. Projected change in hemodynamic measures extrapolated from cross-sectional age relations may differ substantially from actual change, particularly for variables with nonlinear age relations.
Ten-year longitudinal change in aortic stiffness assessed by cardiac MRI in the second half of the human lifespan: the multi-ethnic study of atherosclerosis
