Abstract 16927: Smoking at Age 18 to 30 is Associated with Diastolic Function Over a 25-Year Follow-Up Period: The CARDIA Study

Abstract

Background The association between smoking at an early age with long-term diastolic function is unclear. By echocardiography, the ratio between early diastolic mitral flow velocity (E wave) and the corresponding myocardial velocity (e’ wave) is a robust method to assess diastolic function (E/e’ ratio). We investigated how smoking status at the age of 18 to 30 relates to diastolic function over 25 years. Methods The Coronary Artery Risk Development in Young Adults (CARDIA) is a prospective study that enrolled African-American and White adults in 1985-1986 (baseline). We included participants at the follow-up Year-25 exam with interpretable echocardiography E/e’ ratio. Echocardiography E wave was assessed using pulse wave Doppler, and e’ was calculated using the average of septal and lateral e’ tissue Doppler waves. The influence of smoking status at baseline on E/e’ ratio at year 25 was assessed using both a univariate and a multivariate linear regression model, adjusted for age, gender, ethnicity, body-mass index (BMI), LDL-cholesterol, HDL-cholesterol, heart rate (HR), use of anti-hypertensive medications, systolic blood pressure (SBP), and diabetes mellitus. Results 2,340 participants were included: mean age 25±4 years, 44% white, 43% men. At baseline, 24% were current smokers, 15% former smokers, 2% diabetics, and 2% were taking anti-hypertensive medications; mean values were: HR 65±13 beats/min; SBP 110±11, LDL 110±31 mg/dL; HDL 53±13 mg/dL; and BMI 24±5 kg/m2. The mean value of E/e’ ratio was 7.7 ± 2.5. In the univariate analysis, being a current smoker at baseline showed a statistically significant positive correlation with E/e’ ratio (coefficient 0.37, P <0.01), while being a former smoker did not; R2 for the model was 0.006. In the multivariable model, E/e’ ratio again showed a statistically significant positive correlation with current smoker status (coefficient 0.29, P = 0.01), but not for being a former smoker (coefficient -0.18, P = 0.21). R2 for the model was 0.08. Conclusion Actively smoking at a young age was shown to be associated with worse diastolic function 25 years later, independent of age, gender, or body composition.