Interaction between diabetes and a high ankle-brachial index on mortality risk.
OBJECTIVE
Low ankle-brachial index (ABI) is a predictor of increased mortality. The impact of a high ABI on mortality is less studied. Moreover, diabetes is frequently associated with high ABI and, because of specific mechanisms in diabetic vascular diseases, the relationship with prognosis may be unique. Therefore, our aim was to compare mortality in individuals with and without diabetes according to abnormally low and high ABI.


METHODS
We studied the association between ABI and all-cause and cardiovascular mortality in 6986 participants from the REACH registry, a cohort of 45 years and older stable outpatients at high cardiovascular risk (2875 (41.1%) with diabetes) followed for 4 years.


RESULTS
ABI was normal (0.91-1.29) in 49.5%, low (≤0.9) in 47.5%, and high (≥1.3) in 2.9% of participants. During follow up, 9.9% of participants died (6.5% from cardiovascular causes). A low ABI was associated with cardiovascular mortality (adjusted hazard ratio, HR, 1.98, 95% CI 1.62-2.41) and all-cause mortality (HR 2.01, 95% CI 1.72-2.36), without heterogeneity according to diabetes. In contrast, high ABI was associated with higher risk of all-cause mortality in individuals with diabetes (HR 2.11, 95% CI 1.16-3.84), but not without diabetes (HR 0.82, 95% CI 0.36-1.85; p-value for interaction 0.07). The trend was similar for cardiovascular mortality (HR 2.13, 95% CI 1.03-4.44 and HR 1.05, 95% CI 0.43-2.59 with and without diabetes, respectively; p-value for interaction 0.24).


CONCLUSIONS
In the REACH registry, low ABI was associated with mortality, similarly in individuals without and with diabetes, whereas the association with high ABI was only observed in patients with diabetes.
Diabetology, Hôpital Bichat, and Département Hospitalo-Universitaire FIRE, AP-HP, Paris, France INSERM U1138, Research Center les Cordeliers, Paris, France Paris Diderot University, Paris, France louis.potier@gmail.com.
Louis
L
Potier
Diabetology, Hôpital Bichat, and Département Hospitalo-Universitaire FIRE, AP-HP, Paris, France INSERM U1138, Research Center les Cordeliers, Paris, France Paris Diderot University, Paris, France.
Ronan
R
Roussel
Paris Diderot University, Paris, France INSERM U1148, Paris, France.
Julien
J
Labreuche
Diabetology, Hôpital Bichat, and Département Hospitalo-Universitaire FIRE, AP-HP, Paris, France Paris Diderot University, Paris, France.
Michel
M
Marre
Department of Internal Medicine, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.
Patrice
P
Cacoub
Department of Neurology, Asklepios Klinik Hamburg Altona, Hamburg, Germany.
Joachim
J
Röther
Atlanta VA Medical Center and Cardiology Division, Emory University School of Medicine, Atlanta, GA, USA.
Peter W F
PW
Wilson
Department of Medicine (Cardiology), Tokai University School of Medicine, Isehara, Kanagawa, Japan.
Shinya
S
Goto
Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA.
Deepak L
DL
Bhatt
Paris Diderot University, Paris, France INSERM U1148, Paris, France Cardiology, Hôpital Bichat, and Département Hospitalo-Universitaire FIRE, AP-HP, Paris, France NHLI, Imperial College, Royal Brompton Hospital, London, UK.
Philippe Gabriel
PG
Steg
D000368:Aged; D000369:Aged, 80 and over; D055109:Ankle Brachial Index / Q000401:mortality*; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D003920:Diabetes Mellitus / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D012306:Risk
Cardiovascular risk; diabetes; high ankle–brachial index