Characteristics of studies included in the Arm Based on LEg-BP (ABLE-BP) dataset
| Study name | Period of patient recruitment/duration of trial | Sample size (n enrolled in study) | Country of origin | Eligibility criteria | Primary outcome measure | Blood pressure measurement methods | Intended maximum duration of follow-up | Definition of hypertension | Definition of diabetes | Definition of cardiovascular death and non-fatal cardiovascular event |
| Chicago Walking and Leg Circulation Study (WALCS)31 | 1998–2000 | 440 | USA | Patients without lower extremity peripheral artery disease who were recruited for the non-PAD comparator group. | Subclavian stenosis as a marker for total and cardiovascular disease mortality | Two sequences of BP readings recorded using a 12 cm pneumatic cuff and a hand held Doppler probe (Nicolet Vascular Pocket Dop II, Golden, Colo) with patient supine | Mean follow-up was 4.8 years. | Patient history or use of BP lowering therapy | Patient history or use of oral antidiabetic drugs and/or insulin | Cardiovascular death: any fatal cardiovascular cause. |
| Non-fatal events: MI, stroke, TIA, coronary or peripheral revascularisation, congestive heart failure, PAD, angina | ||||||||||
| Epidemiology of dementia in Central Africa (EPIDEMCA)32 | November 2011– December 2012 | 880 | Central African Republic/ Republic of Congo | Males and females, aged ≥65 years living in areas of Central African Republic and Republic of Congo | Diagnosis of dementia and Alzheimer’s disease and associated risk factors | Two sequences of BP measurements recorded using standard mercury sphygmomanometer, as part of ABI protocol with patients supine. BP rounded to nearest 5 mm Hg | 2–3 years | Self-reported BP lowering treatment; SBP≥140 mm Hg or DBP ≥90 mm Hg | Self-reported or blood glucose >126 mg/dL fasting or >200 mg/dL in non-fasting | Cardiovascular death: stroke, MI or other cardiovascular or cerebrovascular diseases—based on interview of relatives during verbal autopsy at follow-up. |
| Non-fatal events: stroke, MI, other heart disease | ||||||||||
| Fuencarral Health Center33 | 2003–2004 | 1102 | Spain | Males and females, aged 60–79 years, with no known PAD | Low ABI and incidence of death due to cardiovascular causes | BP measured sequentially with Doppler 8-MHz probe (Hadeco, Kawasaki, Japan) and calibrated mercury sphygmomanometer with patient supine | Mean follow-up 49.8 months | SBP ≥140 mm Hg, DBP ≥90 mm Hg or use of BP lowering treatment | Baseline glucose ≥126 mg/dL (>7 mmol/L) on 2 occasions or use of antidiabetic agents | Cardiovascular death: |
| Fatal stroke, MI, sudden death without other cause, death after vascular surgery or procedure, death attributed to heart failure, bowel or limb infarction, any other death not categorically attributed to a non-vascular cause | ||||||||||
| Non-fatal events: MI, stroke or cardiovascular event | ||||||||||
| Heinz Nixdorf Recall Study34 | 2000–2003 | 4617 | Germany | Males and females, aged 45–74 years, in an unselected urban population from the Ruhr area | Coronary artery calcium as predictor for fatal and non-fatal MI. | BP measured sequentially using Doppler probe (Logidop, Kranzbuhler, Germany) with patients supine | Mean follow-up: 109 months | SBP >140 mm Hg or DBP >90 mm Hg | Existing diagnosis or use of antidiabetic medication | Cardiovascular death or non-fatal event: first occurrence of MI based on symptoms, ECG signs, and enzymes, supported by necropsy if fatal |
| Secondary endpoints included ABI as a stroke predictor factors | ||||||||||
| Invecchiare in Chianti (InCHIANTI)35 | August 1998–March 2000 | 1091 | Italy | Males and females, aged ≥65 years, living in Greve and Bagno | Physiological factors influencing walking ability | Single pair of sequential brachial BP readings using standard mercury sphygmomanometer, with patients supine. BP rounded to nearest 5 mm Hg. | N/S | Self-reported, existing, recorded diagnosis or use of BP lowering medication or SBP ≥140 mm Hg or DBP ≥90 mm Hg | Self-reported, existing recorded diagnosis, or use of antidiabetic medication, or fasting glucose >7.0 mmol/L | Cardiovascular death: not defined. |
| Posterior tibial arteries measured twice with a handheld Doppler stethoscope (Parks model 41-A; Parks Medical Electronics, Aloha, Ore). | Non-fatal events: diagnosis of heart disease, MI or angina, stroke or TIA | |||||||||
| Lifestyle Interventions and Independence for Elders (LIFE) study36 | 2010–2011/2.6 years | 1588 | USA | Ambulant community dwelling individuals, aged 70–89 years with a sedentary lifestyle (<20 min per week physical activity) | Major mobility disability | Two pairs of sequential measurements recorded in each arm using handheld Doppler, with patients supine | 2 years | Self-reported or measurement | Self-reported | Cardiovascular fatal or non-fatal events: MI, angina, stroke or TIA, carotid artery disease, congestive heart failure or PAD requiring hospitalisation, outpatient revascularisation for PAD, ruptured abdominal aortic aneurysm |
| Secondary: association between ABI and cognitive function | ||||||||||
| Improving interMediAte RisK management (MARK) study37 | N/S | 2490 | Spain | Males and females living in 3 regions of Spain, aged 35–74 years. Free of atherosclerotic disease, with an intermediate cardiovascular risk (10-year coronary risk of 5%–15% or vascular death risk of 3%–5%) selected at random | Incidence of vascular events | Three pairs of BP measurements in each arm, using an OMRON | 10 years | Patient reported, or use of BP lowering medications or SBP ≥140 mm Hg or DBP ≥90 mm Hg | Patient reported, or use of antidiabetic treatment or fasting glucose ≥126 mg/dL | Cardiovascular death: not defined |
| 705, with patients seated. Legs measured with Vasera device VS-1500 (Fukuda Denshi) | Non-fatal events: stroke or TIA, MI, angina, or revascularisation procedure | |||||||||
| Action for Health in Diabetes (Look AHEAD)38 | June 2001–March 2004 | 339 | USA | Overweight and obese individuals with type 2 diabetes aged 45–76 years, and had a body mass index, 25 kg/m2, or ≥27 kg/m2 if taking insulin | A composite cardiovascular outcome: cardiovascular death, non-fatal MI, non-fatal stroke, hospitalised angina | Two pairs of sequential BP measurements recorded in each arm, using continuous wave Doppler with a standard mercury sphygmomanometer, with patients supine | 4–5 years follow-up | SBP ≥140 mm Hg, ≥DBP > 90 mm Hg or taking BP lowering medication | Self-reported verified from medical records, current treatment, or fasting glucose of ≥126 mg/dL | Cardiovascular death: MI, congestive heart failure, death after cardiovascular intervention, surgery or due to arrhythmia, stroke, presumed cardiovascular death, rapid unexplained cardiovascular death. |
| Secondary: cognitive function | Non-fatal events: stroke, MI, angina, coronary artery bypass grafting or percutaneous coronary intervention, congestive heart failure, carotid endarterectomy, peripheral arterial bypass or angioplasty | |||||||||
| Multi Ethnic Study of Atherosclerosis (MESA)39 | 2000–2002 | 6770 | USA | Males and females, aged 45–84 years, free of clinical cardiovascular diagnoses at baseline | Association of subclavian stenosis with markers of cardiovascular disease | Single pair of sequential BP measurements, using hand-held Doppler instrument and 5-mHz probe, with patients supine | N/S | Self-reported history with use of BP lowering medications, or SBP ≥140 mm Hg or DBP ≥90 mm Hg | Fasting blood glucose ≥126 mg/dL or use of oral hypoglycaemic agents or insulin | Cardiovascular death: death due to atherosclerotic coronary heart disease, stroke, other cardiovascular disease. |
| Non-fatal events: stroke, TIA, MI, angina, revascularisation procedure | ||||||||||
| San Diego Population Study40 | 1994–1998 | 2388 | USA | Males and females, aged 29–91 years, attending a clinic for assessment of PAD and venous disease | Prevalence of PAD | Two pairs of BP measurements, using a continuous-wave Doppler ultrasound, with patients supine | N/S | SBP ≥140 mm Hg or DBP ≥90 mm Hg or use of BP lowering medications | Self-reported or use of antidiabetic medications | Cardiovascular death: not defined |
| Non-fatal events: MI, stroke, angina, coronary angioplasty or bypass graft, or carotid endarterectomy | ||||||||||
| Second Manifestations of ARTerial disease (SMART) study41 | January 2002–February 2014 | 7600 | The Netherlands | Males and females, aged 18–80 years, referred to University Medical Center Utrecht, for treatment of clinically manifest vascular disease or cardiovascular risk factors | 3 point MACE (combination of non-fatal myocardial infarction, non-fatal stroke and death from vascular disease), total mortality and vascular mortality | Single pair of sequential BP measurements, using a Vasoguard Doppler probe, with patients supine | Mean follow-up: 5.9 years | Blood pressure >140/90 mm Hg at baseline or the use of blood pressure lowering medication. | Recorded diagnosis, self-reported diagnosis, use of blood glucose lowering medication, or fasting glucose >7 mmol/L at recruitment combined with initiation of glucose lowering medication within first year of follow-up. | Cardiovascular death: Death from stroke, MI, congestive heart failure, rupture of abdominal aortic aneurysm or vascular death from other causes |
| Type 1 diabetes excluded. | Non-fatal events: stroke (infarction or haemorrhagic), MI, retinal infarction, heart failure | |||||||||
| Surrogate markers for Micro- and Macrovascular hard endpoints as Innovative diabetes tools (SUMMIT)42 | November 2010–June 2013 | 334 | England | Adults over 18 with and without diabetes and/or cardiovascular disease | 6 pairs of simultaneous BP readings using two Omron 705 devices swapped after 3 readings, with patients supine | N/S | Self-reported history of hypertension | HbA1c≥48 mmol/mol | Cardiovascular death: fatal MI | |
| Viborg Women Cohort (ViWoCo)43 | October 2011–January 2013 | 1428 | Denmark | Females born in 1936, 1941, 1946 and 1951 living in the Municipal of Viborg, Denmark | Presence of cardiovascular disease and diabetes mellitus | One pair of simultaneous BP readings, using Omron M2 devices, with patients supine, rounded to nearest 2 mm Hg | Median follow-up 3.3 years | SBP ≥140 mm Hg or DBP ≥90 mm Hg | HbA1c≥48 mmol/mol | Cardiovascular death: fatal event as below |
| Non-fatal event: MI or ischaemic stroke leading to hospitalisation | ||||||||||
| Vietnam Experience Study44 | 1986 | 4394 | USA | Male US army veterans who participated in the Vietnam war | Interarm differences, all-cause and cardiovascular mortality | Two pairs of sequential BP measurements, using standard mercury sphygmomanometer, with patients seated | 15 years | SBP ≥140 mm Hg, DBP ≥90 mm Hg or use of BP lowering medication | Fasting plasma glucose ≥7.0 mmol/L and/or use of medication for diabetes | Cardiovascular death: death due to major cardiovascular disease. |
ABI, ankle-brachial index; BP, blood pressure; DBP, diastolic blood pressure; ECG, Electrocardiogram; IHD, ischaemic heart disease; MI, myocardial infarction; N/S, not stated; PAD, peripheral arterial disease; SBP, systolic BP; TIA, transient ischaemic attack.