Objective: Ankle brachial index (ABI) is a diagnostic tool for peripheral arterial disease; moreover it has a prognostic value for future events. However, the role of intermediate ABI values (0.9 to 1.3) is still unclear. We investigated the interplay of intermediate ABI values with indices of subclinical organ damage in a large cohort of newly diagnosed, never treated hypertensives.

Design and Method: 1,127 newly diagnosed, never-treated hypertensives were recruited. ABI was measured with the oscillometric method and subjects with ABI <0.9 or >1.3 were not included. cfPWV, central BPs, AIx, left ventricular mass index (LVMI), CRP and eGFR were measured. The 10-year risk was calculated using the Framingham Risk Score.

Results: The cohort was young (age: 53±12 years old), with mild-moderate hypertension (systolic BP: 151±18 mmHg, diastolic BP: 90±11 mmHg) and mean ABI value 1.15±0.08. 57.7% were men, 41.3% smoked and 5.9% were diabetics. Left ventricular hypertrophy was detected in 42.2% and the 10-year CVD risk was 15.9±9.6%. ABI correlated with cfPWV, central systolic BP, AIx, LVMI and CRP (r: −0.182, −0.268, −0.195, −0.075, −0.152 respectively, p<0.01 for all). The 10-year risk increased with lower ABI values (r=−0.077, p<0.01). After adjusting for confounders, patients with LVH had higher ABI levels; lower ABI values were observed with worsening eGFR (Figure).

Conclusion: Intermediate ABI values carry prognostic information; they are related to large artery stiffness, impaired central hemodynamic indices, LVH, renal function impairment and 10-year risk of CVD. ABI measurements should be part of an integrated approach to hypertensive patients for both diagnostic and prognostic reasons.