Associations of long-term and early adult atherosclerosis risk factors with aortic and mitral valve calcium

Abstract

Objectives: To determine the association of long-term exposure to atherosclerosis risk factors with valvular calcification.

Background: Traditional atherosclerosis risk factors have been associated with aortic and mitral valve calcium in cross-sectional studies, but long-term prospective data are lacking.

Methods: This was a prospective, community-based cohort study with 27-year follow-up (median follow-up 26.9 years; range 23.1 to 29.6 years). Participants from the Framingham Offspring Study (n = 1,323, enrolled between 1971 and 1975, mean age at enrollment 34 +/- 9 years; 52% women) underwent cardiac multidetector computed tomography assessment between 2002 and 2005. Associations between the long-term average of each cardiovascular risk factor and valve calcium were estimated using logistic regression.

Results: Aortic valve calcium was present in 39% of participants and mitral valve calcium in 20%. In multivariable models, the odds ratio for aortic valve calcium associated with every SD increment in long-term mean total cholesterol was 1.74 (p < 0.0001); with every SD increment in high-density lipoprotein cholesterol, it was 0.77 (p = 0.002); and with every 9 cigarettes smoked per day, it was 1.23 (p = 0.002). Associations of similar magnitude were seen for mitral valve calcium. The mean of 3 serum C-reactive protein measurements was associated with mitral valve calcium (odds ratio: 1.29 per SD increment in C-reactive protein levels; p = 0.002). A higher Framingham risk score in early adulthood (40 years age or younger) was associated with increased prevalence and severity of aortic valve calcium measured 3 decades later.

Conclusions: Exposure to multiple atherosclerotic risk factors starting in early to mid-adulthood is associated with aortic and mitral valve calcium. Studies evaluating early risk factor modification to reduce the burden of valve disease are warranted.

Figure 1. Description of the Framingham Offspring Study and Cardiac Multi-Detector Computed Tomography Sub-study

Figure 2. Prevalence of Aortic Valve Calcium Stratified by Framingham Risk Score Categories in Early Adulthood

Low, intermediate and high cardiovascular risk correspond to a <6%, 6 - <20% and ≥20% 10-year risk of CHD, respectively. Error bars represent 95% confidence intervals. *Adjusted for age and sex

Figure 3. Mean Aortic Valve Calcium Score Stratified by Framingham Risk Score Categories in Early Adulthood

Low, intermediate and high cardiovascular risk correspond to a <6%, 6 - <20% and ≥20% 10-year risk of CHD, respectively. Error bars represent standard errors for calcium score. *Adjusted for age and sex.

Figure 4. Prevalence of Aortic Valve Calcium (A) and Mean Aortic Valve Calcium Score (B) Stratified by Framingham Risk Score in Early Adulthood Among Participants ≤ 40 Years of Age

Low, intermediate and high cardiovascular risk correspond to <6%, 6 - <20% and ≥20% 10-year risk of CHD, respectively. Error bars represent 95% confidence intervals for prevalence and standard errors for calcium score. *Adjusted for age and sex.

Figure 4. Prevalence of Aortic Valve Calcium (A) and Mean Aortic Valve Calcium Score (B) Stratified by Framingham Risk Score in Early Adulthood Among Participants ≤ 40 Years of Age

Low, intermediate and high cardiovascular risk correspond to <6%, 6 - <20% and ≥20% 10-year risk of CHD, respectively. Error bars represent 95% confidence intervals for prevalence and standard errors for calcium score. *Adjusted for age and sex.