Highlights from AHCPR's September Research Activities

Media Advisory Date: October 15, 1997

The Agency for Health Care Policy and Research (AHCPR) works to improve the quality of health care, reduce costs, and broaden access to essential services. Here are some of the findings described in the most recent issue of AHCPR's Research Activities.

Fewer Than One in Five Patients With Diabetes Receives Certain Recommended Screening Tests

Persons with diabetes need regular screening tests to prevent and limit the many serious complications of the disease, ranging from vision and vascular problems to kidney disease. However, a study supported by AHCPR reports that fewer than one in five persons with diabetes receives the minimum number of tests recommended by the American Diabetes Association to monitor diabetes care. Researchers used medical record and billing data to analyze receipt of a subset of diabetic screening tests for 2,312 diabetics enrolled in a health maintenance organization in 1991. They found that more than 40 percent of insulin users and more than 30 percent of non-insulin-dependent diabetics did not have a single glycosylated hemoglobin test during the year. This test detects elevated blood sugar levels that indicate poor diabetes control and increased risk of complications. Many diabetics also did not receive other recommended tests for cholesterol levels and kidney function. No differences were detected by race in the overall rate of receipt of recommended tests. It's not clear whether this failure to follow ADA recommendations was due to lack of physician knowledge or time with the patient or patient ignorance about the importance of diabetic care, says Kimberlydawn Wisdom, M.D., M.S., of the Henry Ford Health System in Detroit.

["Comparison of laboratory test frequency and test results between African-Americans and Caucasians with diabetes: Opportunity for improvement," by Dr. Wisdom, Jon P. Fryzek, Ph.D., Suzanne L. Havstad, M.A., and others, in the June 1997 Diabetes Care 20(6), pp. 971-977.]

Echocardiography Rarely Changes Diagnosis or Management of Patients with Suspected Mitral Valve Prolapse

The gain from the use of echocardiography—essentially a sonogram of the heart—may not be worth the expense in patients with suspected mitral valve prolapse (MVP). This condition, which affects 4 percent of the population, is associated with a small but significant risk of endocarditis (inflammation of the membrane lining the chambers of the heart), a potentially life-threatening condition. Antibiotic prophylaxis is believed to reduce this risk, and the preventive use of antibiotics has been recommended for patients thought to be at high risk of MVP. Because the physical findings associated with MVP tend to be subtle, physicians often use echocardiograms (ECHOs) rather than just a stethoscope to diagnose patients with suspected MVP. Researchers performed ECHOs on 147 patients who were referred to a university hospital echocardiography laboratory to rule out MVP. Based on the results, 14 percent of patients either should have begun (6 patients) or discontinued (14 patients) preventive antibiotic use. However only 4 percent of patients actually changed their use of antibiotics. Therefore, only 4 management changes were made per 131 ECHOs, resulting in $36,250 in hospital and physicians costs per management change.

["The clinical impact of echocardiography on antibiotic prophylaxis use in patients with suspected mitral valve prolapse," by Paul A. Heindenreich, M.D., Jeffrey Bear, B.S., Warren Browner, M.D., and Elyse Foster, M.D., in the April 1997 American Journal of Medicine 102, pp. 337-343.]

Abnormal Blood TnT Levels Indicate Patients at Risk for Heart Complications Following Major Noncardiac Surgery

Patients with abnormally high levels of cardiac troponin T (TnT) after major noncardiac surgery have over five times the risk of cardiac problems during the subsequent 6 months, concludes a study supported in part by AHCPR. TnT is a muscle protein that inhibits contraction of the heart muscle. Researchers studied 772 patients who underwent major noncardiac procedures and did not have major cardiovascular complications while hospitalized. Measurements of TnT levels were taken in the recovery room and over the next 2 days, and researchers interviewed the 722 of the patients 6 months later. They found that of the 2.5 percent of patients who had congestive heart failure or new cardiac arrhythmias within 6 months of hospitalization, 42 percent had elevated peak TnT levels compared with only 11 percent of patients without complications after hospital discharge. Cardiac TnT levels may enhance identification of patients at high risk of cardiovascular events following major surgery, concludes, Lee Goldman, M.D., M.P.H., F.A.C.C., of the University of California, San Francisco School of Medicine.

["Prognostic value of cardiac troponin T after noncardiac surgery: 6-month follow-up data," by Francisco Lopez-Jimenez, M.D., Dr. Goldman, David B. Sacks, M.D., and others in the May 1997 Journal of the American College of Cardiology 29, pp.1241-1245.]

State Regulatory Policies Appear to Constrain Growth in Nursing Home Beds

A study supported by AHCPR indicates that states with regulatory policies, such as Certificate of Need (CON) and Moratorium (MOR) programs, intended to control nursing home expenditures had less growth in nursing home beds than states without these policies. Medicaid nursing home reimbursement rates were not related to changes in the numbers of beds. By 1991, 44 states had a CON or MOR policy in effect. The total number of nursing home beds in the United States grew from 1.93 million to 1.72 million between 1981 and 1993. However, the rate of growth varied dramatically from state to state, ranging from 23 beds per 1,000 elderly persons in Nevada to 85 beds per 1,000 elderly persons in Nebraska. These findings are based on data obtained from five telephone surveys of state officials about CON and MOR policies, Medicaid reimbursement rates, and licensed nursing home beds.

["The effect of certificate of need and moratoria policy on change in nursing home beds in the United States," by Charlene Harrington, Ph.D., James H. Swan, Ph.D., John A. Nyman, Ph.D., and Helen Carrillo, M.S., in Medical Care 35(6), pp. 574-588, 1997.]

Other articles in Research Activities include findings on:

• Chest pain diagnosis in the emergency department.
• Home care use by people with AIDS.
• Factors influencing patient decisions about end-of-life care.
• The best place to treat nursing home patients with pneumonia.
• Use of antibiotics for outpatient treatment of pneumonia.
• Variations in post-stroke rehabilitation practices.
• Need for child-focused health services research.

For additional information, contact AHCPR Public Affairs: Salina Prasad, (301) 427-1864 (SPrasad@ahrq.gov).