GPs told to target inter-arm blood pressure differences

GPs are being urged to routinely identify patients with inter-arm differences in systolic blood pressure of 15mmHg or greater and target them for aggressive management of risk factors, in a recommendation being considered for upcoming NICE guidance.

A major new UK meta-analysis of 20 studies found a difference of 15mmHg or more was a ‘signal' of increased vascular disease or death, with the researchers recommending NICE go further than its current advice that a difference of more than 20mmHg ‘may suggest pathology warranting specialist referral'.

The research – published in the Lancet today – found a systolic difference between arms of more than 15mmHg was associated with a 60% increase in all-cause mortality – a finding Pulse has learned will be considered by the NICE peripheral arterial disease guideline development group.

The authors said GPs should monitor inter-arm blood pressures and manage the risk factors of those with differences of 15mmHg or more ‘aggressively'.

They found such an inter-arm difference in systolic blood pressure was associated with a 2.5-fold increased risk of PAD, a 60% increased risk of pre-existing cerebrovascular disease and a 70% raised risk of cardiovascular mortality.

Study leader Dr Christopher Clark, a GP in Devon and clinical academic fellow at Peninsula Medical School, said: ‘Findings from our study should be incorporated into future guidelines for hypertension to justify bilateral brachial measurement in the assessment of individuals, and aggressive risk-factor management in subjects with a demonstrable systolic between-arm difference.'

An accompanying editorial from Dr Richard McManus, professor of primary care research at the University of Oxford and a GP in Birmingham, and Dr Jonathan Mant, professor of primary care research at the University of Cambridge, said the study justified using inter-arm blood pressure as a sign of disease, although ankle-brachial blood pressure would still be needed for a diagnosis of PAD.

They said: ‘Ascertainment of differences should become part of routine care, as opposed to a guideline recommendation that is mostly ignored.'

Professor Andrew Bradbury, professor of vascular surgery at the University of Birmingham and a member of the NICE PAD guideline development group, said he would be ensuring it looked at the new study: ‘We are likely to be recommending measuring blood pressure in both arms as routine, but it is good to have [these findings] to add heavyweight support.

‘Most people can be treated in primary care – stopping smoking, getting cholesterol down, diagnosing diabetes. Unfortunately, it usually gets overlooked.'

Dr Anita Sharma, a GP in Oldham and also a member of the NICE guideline development group for PAD, said inter-arm differences could easily be monitored and treated in primary care: ‘I don't think this would be difficult.

‘It can be done in primary care and we do know if you diagnose and address these things early we can reduce mobility and mortality.'