Coronary artery calcification in older adults to age 99: prevalence and risk factors.

BACKGROUND: Coronary artery calcification has been proposed as a noninvasive method to assess cardiovascular disease (CVD) risk. However, the prevalence and risk factors for coronary artery calcification in populations >65 years have not been well studied. METHODS AND RESULTS: Electron beam tomography was performed to assess coronary artery calcium (CAC) in 614 older adults aged, on average, 80 years (range, 67 to 99 years); 367 (60%) were women, and 143 (23%) were black. Calcium scores ranged from 0 to 5459. Median scores were 622 for men and 205 for women. Scores increased by age and were lower in blacks than in whites. Nine percent of subjects (n=57) had no CAC, and 31% (n=190) had a score lower than 100. A history of CVD was associated with calcium score. Age, male sex, white race, CVD, triglyceride level, pack-years of smoking, and asthma, emphysema, or bronchitis (chronic obstructive pulmonary disease) were independently associated with CAC score in the fourth quartile. CONCLUSIONS: A wide range of CAC scores was observed, suggesting adaptation with aging. CAC may have potential to predict CVD in older adults, but this remains to be determined.

The role of comorbidity in the assessment of intermittent claudication in older adults.

The prevalence of intermittent claudication (IC) in older adults by questionnaire is less than 5% while the prevalence of peripheral arterial disease (PAD) by non-invasive testing is 2-4-fold higher. Comorbid conditions may result in under-reporting intermittent claudication (IC) as assessed by the Rose Questionnaire. We examined characteristics of those who report leg pain in relationship to other comorbid conditions and disability in 5888 participants of the Cardiovascular Health Study (CHS). Older adults with exertional leg pain, not meeting criteria for IC, had a higher prevalence of PAD on non-invasive testing with the ankle-arm index than those without pain, as well as a higher prevalence of arthritis. The pattern of responses suggested that pain for both conditions was reported together. The Rose Questionnaire for IC is specific for PAD, but a negative questionnaire does not indicate a lack of symptoms, rather the presence of PAD along with other conditions that can cause pain.

Prevalence and risk factors for abdominal aortic aneurysms in older adults with and without isolated systolic hypertension.

An association between abdominal aortic aneurysm (AAA) and atherosclerotic disease has been recognized and may be due to shared risk factors. A consistent relation between blood pressure and AAA has not been found. AAA was compared between those with and without isolated systolic hypertension (ISH) and prevalence of aortic atherosclerosis was evaluated. Abdominal aortic ultrasound was performed in 266 people, 143 with ISH and 123 age-similar controls. AAA was defined as an infrarenal aortic diameter of > or = 3.0 cm or an infrarenal-to-suprarenal diameter ratio of > or = 1.2. The average age of participants was 73 years. Overall prevalence of AAA was 9.4%, 11.9% in those with ISH and 6.5% among normotensives (p = 0.134). Multivariate analysis revealed male gender (p <0.001), higher low-density lipoprotein (p <0.001), higher pulse pressure (p = 0.032), and current smoking (p = 0.012) to be independent predictors of AAA. When evaluating aortic atherosclerosis, those with AAA had significantly larger diameters of the iliac arteries along with greater intimamedia thickness of the iliac arteries. Those with and without aneurysms had a similar prevalence of plaque (89% to 96%), but measured plaques tended to be larger among those with than without AAA (p <0.001). Progression of AAA after 1 year was observed in 8 participants, with a mean diameter change of 3.42 mm. AAA was found to be independently associated with pulse pressure but not with systolic blood pressure. Patients with AAA also had greater wall thickness and greater diameter of the iliac arteries, which are probably associated with the underlying disease process.

Organizational structure and communication strategies of the bypass angioplasty revascularization investigation: a multicenter clinical trial.

Efficient communication is a challenge for the many operating components of a multicenter randomized clinical trial. Traditional management theory states that communications generally flow along a path established by a hierarchical organizational structure. A multicenter clinical trial does not fit traditional organizational models well and requires modification of traditional communication techniques. While the scientific community typically views a clinical trial as one large and cohesive enterprise, at each site the trial may actually be conducted as a small project related to the medical specialty of the investigator. Therefore overall trial management must be accomplished through collaboration rather than through direct management. In the Bypass Angioplasty Revascularization Investigation (BARI), the BARI clinical coordinating center has designed and utilized several mechanisms that facilitate effective communication and administrative control of a multicenter clinical trial. These mechanisms provide a framework of communication techniques that accommodate the specific needs of a complex organization.