Ankle-brachial index, toe-brachial index, and cardiovascular mortality in persons with and without diabetes mellitus.

BACKGROUND The prognostic utility of the ankle-brachial index (ABI) may be hampered in persons with diabetes due to peripheral arterial stiffening in the ankles. Stiffening of toe arteries occurs infrequently in diabetes. We aimed to determine the nature of the relationship of the toe-brachial index (TBI) and ABI with cardiovascular disease (CVD) mortality and to determine whether the associations are modified in individuals with diabetes. METHODS Individuals with clinically suspected atherosclerotic peripheral arterial disease who underwent ABI and TBI measurements in a vascular laboratory were monitored longitudinally for CVD mortality. RESULTS Among 469 participants (89% men), the mean age was 68 ± 9 years, and 36% had diabetes. The mean ABI was 0.83 ± 0.28 and the mean TBI was 0.60 ± 0.24. During median 7.0 years of follow-up, there were 158 CVD deaths. The association of the ABI categories with CVD deaths differed in diabetic vs nondiabetic participants (P = .002 for interaction). In contrast, the association of the TBI categories with CVD deaths was similar, irrespective of diabetes status (P = .17 for interaction). Among diabetic patients, a U-shaped relationship was observed between ABI categories and CVD death: those with low (<0.90) and high (>1.30) ABIs were both at higher risk than those with normal ABIs (range, 0.90-1.30). In nondiabetic patients, association of ABI categories with CVD death was linear, such that those with an ABI >1.30 were at the lowest risk, whereas those with an ABI <0.90 were at higher risk. In contrast, the association of TBI categories with CVD death was linear irrespective of diabetes status. High TBI categories consistently predicted low risk, whereas risk was higher with progressively lower TBI categories. CONCLUSIONS Among diabetic individuals with clinically suspected peripheral arterial disease, those with low and high ABIs are both at higher risk of CVD death. In contrast, a linear relationship was observed between TBI categories and CVD death irrespective of diabetes status. These findings suggest that stiffened ankle arteries may limit the predictive value of the ABI in individuals with diabetes, a limitation that may be overcome by measurement of the TBI.

[1]  W. Roberts,et al.  Medial calcinosis of Mönckeberg. A review of the problem and a description of a patient with involvement of peripheral, visceral and coronary arteries. , 1977, The American journal of medicine.

[2]  T. Orchard,et al.  Assessment of Peripheral Vascular Disease in Diabetes Report and Recommendations of an International Workshop* Sponsored by the American Diabetes Association and the American Heart Association September 18‐20, 1992 New Orleans, Louisiana , 1993, Circulation.

[3]  J. Adams,et al.  Medial arterial calcification in the feet of diabetic patients and matched non-diabetic control subjects , 1993, Diabetologia.

[4]  P. Ridker,et al.  Risk Factors for Progression of Peripheral Arterial Disease in Large and Small Vessels , 2006, Circulation.

[5]  T Rantanen,et al.  Prevalence and risk factors of PAD among patients with elevated ABI. , 2008, European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery.

[6]  P. Bennett,et al.  Medial arterial calcification and its association with mortality and complications of diabetes , 1988, Diabetologia.

[7]  L. Norgren,et al.  Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II). , 2007, Journal of vascular surgery.

[8]  V. Aboyans,et al.  The ankle-brachial index and incident cardiovascular events in the MESA (Multi-Ethnic Study of Atherosclerosis). , 2010, Journal of the American College of Cardiology.

[9]  R. Langer,et al.  Quantitative and qualitative progression of peripheral arterial disease by non-invasive testing , 1999, Vascular medicine.

[10]  W M O'Fallon,et al.  Reproducibility of noninvasive tests of peripheral occlusive arterial disease. , 1985, Journal of vascular surgery.

[11]  A. Gamst,et al.  Subclavian artery stenosis: prevalence, risk factors, and association with cardiovascular diseases. , 2004, Journal of the American College of Cardiology.

[12]  S. Carter,et al.  Systolic pressures in the extremities of man with special reference to the toes. , 1970, Canadian journal of physiology and pharmacology.

[13]  Rodney A. White,et al.  ACC/AHA 2005 Practice Guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography , 2006, Circulation.

[14]  Loki Natarajan,et al.  The association between elevated ankle systolic pressures and peripheral occlusive arterial disease in diabetic and nondiabetic subjects. , 2008, Journal of vascular surgery.

[15]  M. Criqui,et al.  Test characteristics of the ankle-brachial index and ankle-brachial difference for medial arterial calcification on X-ray in type 1 diabetes. , 2012, Journal of vascular surgery.

[16]  R. Hoyt,et al.  Peripheral arterial disease in people with diabetes: response to consensus statement. , 2004, Diabetes care.

[17]  F. Kronenberg,et al.  Predictive performance of renal function equations for patients with chronic kidney disease and normal serum creatinine levels. , 2002, Journal of the American Society of Nephrology : JASN.

[18]  A. Sawka,et al.  Effect of Temperature on Digital Systolic Pressures in Lower Limb in Arterial Disease , 1992, Circulation.

[19]  F. Fowkes,et al.  The measurement of atherosclerotic peripheral arterial disease in epidemiological surveys. , 1988, International journal of epidemiology.

[20]  K. Johnston,et al.  Reproducibility of noninvasive vascular laboratory measurements of the peripheral circulation. , 1987, Journal of vascular surgery.