Abstract
BACKGROUND: Federal law requires certain private insurers to cover and waive patient cost sharing for preventive medical services that receive a grade of B or better from the U.S. Preventive Services Task Force (USPSTF). The USPSTF recommends that asymptomatic adults who have a blood pressure (BP) higher than 135/80 mmHg be screened for type 2 diabetes. PURPOSE: The goals of this study were to determine the sensitivity and specificity of the USPSTF screening criteria and to determine the prevalence of cardiovascular risk factors and comorbidity among undiagnosed individuals by USPSTF criteria. METHODS: Data come from 7189 adults who participated in the 2003-2010 National Health and Nutrition Examination Survey; statistical analysis was conducted in 2011-2012. Participants with fasting plasma glucose ≥126 mg/dL or hemoglobin A1c (HbA1c) ≥6.5% who did not self-report a diagnosis of diabetes were categorized as having undiagnosed diabetes. RESULTS: Among people without diagnosed diabetes, 4.0% had undiagnosed diabetes. The proportion of adults with undiagnosed diabetes who were identified (sensitivity) using BP >135/80 mmHg as the screening standard was 44.4%; among individuals without undiagnosed diabetes, 74.8% had BP ≤135/80 mmHg (specificity). For those with undiagnosed diabetes, the prevalence of HbA1c 7.0%-<8.0% was 10.6% for those with BP ≤135/80 mmHg and 14.3% for those with BP >135/80 mmHg; and 12.8% and 9.4% for HbA1c ≥8.0%, respectively. Elevated low-density lipoprotein (100-160 mg/dL) was similar by BP cut-point (52%-53%). For those with BP ≤135/80 mmHg, 16.7% had a history of cardiovascular disease and 22.9% had chronic kidney disease. CONCLUSIONS: The USPSTF screening recommendations result in missing more than half of those who have undiagnosed diabetes, and a substantial proportion of these people have increased low-density lipoprotein and other cardiovascular risk factors.