ith a 2coil anterior surface coil array positioned on the chest as a 2-coil phased array integrated in the patient bed for posterior signal reception. Image acquisition was gated electrocardiographically. MBF was determined by PTK/ZK web model-independent deconvolution and expressed as mL/g/min. Spirometry Spirometry was conducted in 20042006 and in accordance with the American Thoracic Society/European Respiratory Society guidelines using a dry-rolling-sealed spirometer with software that performed automated quality checks in real time. Cardiac CT scans were performed at full inspiration on multi-detector and electron-beam CT scanners. Two scans were performed on each participant; the scan with the higher air volume was used for analyses except in cases of discordant scan quality, in which case the higher quality scan was used. Image attenuation was assessed using modified Pulmonary Analysis Software Suite at a single reading center by trained readers without knowledge of other participant information. The attenuation of each pixel in the lung regions was linearly corrected, such that 
the mean attenuation outside the body was 21000 and aortic was 50 Hounsfield Units. %LAA was defined as the percentage of the total voxels in the lung below 2910 HU. This threshold was chosen based upon pathology comparisons and the generally mild degree of emphysema in the sample. Sensitivity analyses were performed using %LAA defined as the percentage of the total voxels in the lung below 2950 HU. %LAA measures from the carina to lung base are highly correlated with full-lung measures on the same full-lung scans in smokers. %LAA measures from cardiac scans correlated with those from full-lung scans from the same MESA participants and have been used in this cohort to confirm multiple prior hypotheses,. two measures were used in calculations. Current smoking was confirmed by urinary cotinine levels . Covariates Information on age, gender, race/ethnicity, educational attainment, occupational exposure to dust, fumes, or smoke, environmental tobacco smoke exposure, family history of emphysema, medical history and medication use were self-reported using standardized questionnaire items,, as recommended. Height, weight and resting blood pressure were measured using standard techniques, the latter using the Dinamap Monitor PRO 100. Serum glucose and lipids, including high- and low-density lipoproteins, were measured after 12-hour fast. The presence of diabetes mellitus was defined as fasting serum glucose level.126 mg/dL or current use of any diabetes medication. Statistical Analysis The cohort was stratified by quartile of CRVE for descriptive purposes. Multivariate mean differences in lung function and %LAA were estimated using generalized linear models that regressed CRVE, CRAE, log-transformed ACR and MBF on spirometric and %LAA measurements after adjustment for age, gender, race/ethnicity, height, body mass index, waist and hip circumference. For CT analyses, models were also adjusted for scanner type and mAs. Multivariate models were then additionally adjusted for cigarette smoking status, cigarette pack years and urine cotinine, and subsequently the potential confounders listed Smoking Cigarette, cigar and pipe smoking was self-reported using standardized questionnaire items. Lung Function and Systemic Microvascular Changes in the footnotes to the tables. The presence of effect modification by smoking was tested with the 2 log likelihood test of nested models with