The prognosis of diabetic patients with high ankle-brachial index depends on the coexistence of occlusive peripheral artery disease.
Résumé
OBJECTIVES: High ankle-brachial index (ABI) (>1.40) is associated with poor cardiovascular disease (CVD) prognosis. Concomittant peripheral artery disease (PAD) is frequent, although undetectable with the ABI in this situation. We assessed the prognostic value of a high ABI according to the coexistence of occlusive PAD in diabetics. METHODS: In this retrospective longitudinal study, we reviewed the data of 403 consecutive diabetic patients (hospitalized in tertiary care teaching hospital) who had a Doppler assessment of their lower limbs between 1999 and 2000. They were classified as "normal" when Doppler waveform patterns (DWP) were normal and ABI within the 0.91 to 1.39 range, "occlusive-PAD (O-PAD)" when ABI ≤0.90, or in case of abnormal DWP with normal ABI, "isolated medial calcinosis (IMC)" if ABI ≥1.40 with normal DWP, and "mixed disease (MD)" when ABI ≥1.40 with abnormal DWP. The primary outcome was the occurrence of any of the following events: death, stroke or transient ischemic attack (TIA), and acute coronary syndrome. RESULTS: The patients (65.6 ± 13.2 years, 54.6% females) were classified as normal (14.4%), O-PAD (48.4%), IMC (16.4%), and MD (20.8%). During a mean follow-up of 6.5 years, the event-free survival curves of O-PAD and MD groups showed equally poorer prognosis than the IMC and normal groups. Adjusted for age, sex, diabetes type and duration, traditional CVD risk factors, chronic kidney disease, CVD history and treatments, the presence of occlusive disease (hazard ratio [HR]: 2.21, 1.16-4.22, P = .016), but not medial calcinosis, was significantly associated with the primary outcome. CONCLUSIONS: In diabetics with ABI >1.40, only those with concommittant occlusive PAD have poorer prognosis.