A1c and cardiovascular risk scores identify those who can benefit from preventive interventions, according to the ADDITION study….
The measurement of HbA1c is suggested as a diagnostic test for diabetes. Screening for diabetes also identifies individuals with elevated cardiovascular risk but who are free of diabetes. This study aims to assess whether screening by HbA1c or glucose measures alone, or in combination with a cardiovascular risk assessment, identifies people who may benefit from preventive interventions, i.e. people with screen detected diabetes and people belonging to groups with excess mortality, during a median follow-up of 7 years.
A population-based, stepwise high-risk screening program was performed in 193 family practices from 2001 to 2006. Individuals aged between 40 and 69 years (N = 163,185) were sent a diabetes risk questionnaire. Of these, 20,916 people at risk of diabetes were stratified by glucose measures (normal glucose tolerance [NGT], impaired fasting glucose [IFG], impaired glucose tolerance [IGT] and diabetes), HbA1c (<6%; 6.0–6.4%; or ≥6.5%) and cardiovascular risk (heart SCORE <5 or ≥5). People were followed for a median of 7 years or until death. Excess mortality was calculated using the Cox hazard ratio (HR).
SCORE ≥ 5 identified 91.7% (95% CI 91.1–92.3%) of those who might benefit from preventive interventions. SCORE ≥ 5 in combination with HbA1c ≥ 6.0% identified 96.7% (95% CI 96.3–97.0%), compared with 97.6% (95%CI 97.2–97.9%) in combination with glucose measures. Glucose measures or HbA1c alone identified 26.1% (95% CI 25.2–27.0%) and 19.8% (95% CI 19.0–20.6%), respectively.
In a population-based high risk screening program in primary care, HbA1c ≥ 6.0% combined with an elevated cardiovascular risk assessment (SCORE ≥ 5) can feasibly be used to identify those who may benefit from preventive lifestyle intervention and/or polypharmacy.