Meta-analysis of exercise testing to detect coronary artery disease in women

Diabetes risk score: towards earlier detection of type 2 diabetes in general practice

BACKGROUND

Type 2 diabetes is common, costly and often goes unrecognised for many years. When patients are diagnosed, the majority exhibit associated tissue damage or established cardiovascular risk. Evidence is accumulating that earlier detection and management of diabetes and related metabolic abnormalities may be beneficial. We aimed to develop and evaluate a score based on routinely collected information to identify people at risk of having undetected diabetes.

METHODS

A population-based sample of 1077 people, aged 40 to 64 years, without known diabetes, from a single Cambridgeshire general practice, underwent clinical assessment including an oral glucose tolerance test. In a separate 12-month study, 41 practices in southern England reported clinical details of patients aged 40 to 64 years with newly diagnosed Type 2 diabetes. A notional population was created by random selection and pooling of half of each dataset. Data were entered into a regression model to produce a formula predicting the risk of diabetes. The performance of this risk score in detecting diabetes was tested in an independent, randomly selected, population-based sample.

RESULTS

Age, gender, body mass index, steroid and antihypertensive medication, family and smoking history contributed to the score. In the test population at 72% specificity, the sensitivity of the score was 77% and likelihood ratio 2.76. The area under the receiver-operating characteristic curve was 80%.

CONCLUSIONS

A simple score, using only data that are routinely collected in general practice, can help identify those at risk of diabetes. This score could contribute to efficient earlier detection through case-finding or targeted screening.

Lack of association of lipoprotein(a) levels with coronary calcium deposits in asymptomatic postmenopausal women

OBJECTIVES

This study sought to determine the relationship of lipoprotein(a) (Lp(a)) and other cardiac risk factors to coronary atherosclerosis as measured by calcification of coronary arteries in asymptomatic postmenopausal women.

BACKGROUND

Lipoprotein(a) is considered a risk factor for coronary heart disease. Coronary calcium deposition is believed to be a useful noninvasive marker of coronary atherosclerosis in women. However, to our knowledge, there are no reports of the relationship of Lp(a) to coronary calcium in postmenopausal women.

METHODS

In 178 asymptomatic postmenopausal women (64 +/- 8 years), we measured Lp(a) and other cardiac risk factors: age, hypertension, diabetes, low-density lipoprotein cholesterol, smoking status, body mass index, physical activity level and duration of hormone replacement therapy. Electron-beam computed tomography was done to measure coronary calcium (calcium score). We analyzed the relationship between calcium score and cardiac risk factors using multivariate analysis.

RESULTS

Although calcium score correlated with traditional risk factors of age, diabetes, hypertension and smoking, it did not correlate with Lp(a) in the asymptomatic postmenopausal women. Similar multivariate analyses were done in the subjects age >60 years and in the subjects with significant coronary calcium deposit (calcium score > or =50). These analyses also have failed to show an association of levels of Lp(a) with coronary calcium deposits.

CONCLUSIONS

We conclude that in asymptomatic postmenopausal women, Lp(a) levels do not correlate with coronary atherosclerosis as measured by coronary calcium deposits.

Diagnosis of suspected coronary artery disease in women: a cost-effectiveness analysis

BACKGROUND

The optimal strategy for the diagnosis of coronary artery disease (CAD) in women is not well defined. We compared the cost-effectiveness of several strategies for diagnosing CAD in women with chest pain.

METHODS

We performed decision and cost-effectiveness analyses with simulations of 55-year-old ambulatory women with chest pain. With a Markov model, simulations of patients underwent exercise electrocardiography, exercise testing with thallium scintigraphy, exercise echocardiography, angiography, or no workup.

RESULTS

Diagnosis with angiography cost less than $17, 000 per quality-adjusted life-year compared with exercise echocardiography if the patient had definite angina and less than $76,000 per life-year if she had probable angina. If she had nonspecific chest pain, diagnosis with exercise echocardiography increased life-years compared with no testing.

CONCLUSIONS

Cost-effectiveness of first-line diagnostic strategy for diagnosis of CAD in women varies mostly according to pretest probability of CAD. Diagnosis of coronary artery disease with angiography is cost-effective in 55-year-old women with definite angina. In 55-year-old women with probable angina, diagnosis with angiography would increase quality-adjusted life-years but significantly increase costs. Use of exercise echocardiography as a first-line diagnosis for CAD is cost effective in 55-year-old women with probable angina and nonspecific chest pain.