Ankle BP may predict future peripheral artery disease

27th April 2024, A/Prof Chee L Khoo

Ankle BP

PAD is associated with a high incidence of future lower-limb amputations, physical disability, cardiovascular outcomes, other serious health outcomes, reduced quality of life, and mortality (3–8). Some GPs are lucky to have tool that can easily perform ankle brachial index (ABI) as part of a cardiovascular assessment. It is a very simple tool that can detect peripheral arterial disease (PAD). . The ankle–brachial index (ABI), which is the ratio of the ankle and arm systolic BP (SBP). It is commonly used to screen for PAD. However, it has limited discriminative value in unselected patients12 or in those with complicated diabetes or chronic kidney disease (CKD) who have a high prevalence. There are other calculated ankle and arm indices that we can use to better predict future PAD as well mortality.

We are all used to the Ankle-Brachial Index (ABI) which is the highest of arm systolic BP/ankle (or thigh) BP. Obviously, the lower the ABI the more likely that there is PAD. Mohammedi K et al look at other indices that may be more useful than just ABI (1). They used Arm Systolic BP (ArmSysBP), Arm Diastolic BP (ArmDiasBP), Ankle Systolic BP (AnkleSysBP) and Arm Pulse Pressure (APP) Ankle Pulse Pressure (AnklePP) to explore the association of those indices with future PAD risk and mortality. See Table 1. They published their findings a few months ago in the European Heart Journal (1).

They used data from 3 previously published dataset – ORIGIN, ONTARGET and TRANSEND (2-5). After excluding patients with incomplete data and patients with history at baseline of PAD (non-traumatic amputation, lower limb angioplasty, endarterectomy or lower limb bypass surgery), there were data from 40 747 participants who did not have PAD at baseline.

The primary outcome was incident clinical PAD (defined as non-traumatic amputation, lower limb angioplasty, endarterectomy or lower limb bypass surgery). Secondary outcomes were a composite comprising clinical PAD or death and all-cause death. The reference value for ArmSysBP was 140 mmHg, ArmDiasBP 80mmHg, AnkleSysBP 150mmHg, ArmPP 60mmHg and AnklePP 80mmHg.

The mean age of the participants was 65.6 years. 50.2% had a history of diabetes. 61.3% had a history of cardiovascular disease. During a mean follow up period of 5 years, clinical PAD occurred in 2.6%. The higher the arm BP and the lower the ankle BP were, the higher the risk of PAD or death and all-cause mortality. They were independent of whether the subjects had diabetes or cardiovascular disease. The strongest association were ankle SBP, ABI, and APPD, which provided the highest prognostic performance in predicting future clinical PAD. Overall, ankle SBP and APPD outperformed arm BP measures and performed comparably with ABI for predicting these outcomes. Ankle BP indices had high specificity but low sensitivity.

Teaching moments – what has this study taught us?

We already know that patients with diabetes +/- CV diseases have higher risks of PAD and vice versa. We also know that ABI is a great tool in finding patients with PAD as well as predicting PAD related morbidity or mortality. Patients with PAD have a higher mortality risk. One of the known problems with ABI is that calcified peripheral arteries may give a higher ABI reading. Additional indices as indicated in this study may help to detect some of those cases.


  1. Mohammedi K, Pigeyre M, Bosch J, Yusuf S, Gerstein HC. Arm and ankle blood pressure indices, and peripheral artery disease, and mortality: a cohort study. Eur Heart J. 2024 Mar 1:ehae087. doi: 10.1093/eurheartj/ehae087
  2. Yusuf S, Teo K, Anderson C, Pogue J, Dyal L, Copland I, et al. Effects of the angiotensin receptor blocker telmisartan on cardiovascular events in high-risk patients intolerant to angiotensin-converting enzyme inhibitors: a randomised controlled trial. Lancet 2008;372:1174–83.
  3. Yusuf S, Teo KK, Pogue J, Dyal L, Copland I, Schumacher H, et al. Telmisartan, ramipril, or both in patients at high risk for vascular events. N Engl J Med 2008;358:1547–59.
  4. Bosch J, Gerstein HC, Dagenais GR, Diaz R, Dyal L, Jung H, et al. n-3 fatty acids and cardiovascular outcomes in patients with dysglycemia. N Engl J Med 2012;367:309–18.
  5. Gerstein HC, Bosch J, Dagenais GR, Diaz R, Jung H, Maggioni AP, et al. Basal insulin and cardiovascular and other outcomes in dysglycemia. N Engl J Med 2012;367:319–28.