Effectiveness of bedside investigations to diagnose peripheral artery disease among people with diabetes mellitus: A systematic review

Abstract

As a progressive disease process, early diagnosis and ongoing monitoring and treatment of lower limb peripheral artery disease (PAD) is critical to reduce the risk of diabetes‐related foot ulcer (DFU) development, non‐healing of wounds, infection and amputation, in addition to cardiovascular complications. There are a variety of non‐invasive tests available to diagnose PAD at the bedside, but there is no consensus as to the most diagnostically accurate of these bedside investigations or their reliability for use as a method of ongoing monitoring. Therefore, the aim of this systematic review was to first determine the diagnostic accuracy of non‐invasive bedside tests for identifying PAD compared to an imaging reference test and second to determine the intra‐ and inter‐rater reliability of non‐invasive bedside tests in adults with diabetes. A database search of Medline and Embase was conducted from 1980 to 30 November 2022. Prospective and retrospective investigations of the diagnostic accuracy of bedside testing in people with diabetes using an imaging reference standard and reliability studies of bedside testing techniques conducted in people with diabetes were eligible. Included studies of diagnostic accuracy were required to report adequate data to calculate the positive likelihood ratio (PLR) and negative likelihood ratio (NLR) which were the primary endpoints. The quality appraisal was conducted using the Quality Assessment of Diagnostic Accuracy Studies and Quality Appraisal of Reliability quality appraisal tools. From a total of 8517 abstracts retrieved, 40 studies met the inclusion criteria for the diagnostic accuracy component of the review and seven studies met the inclusion criteria for the reliability component of the review. Most studies investigated the diagnostic accuracy of ankle ‐brachial index (ABI) (N = 38). In people with and without DFU, PLRs ranged from 1.69 to 19.9 and NLRs from 0.29 to 0.84 indicating an ABI <0.9 increases the likelihood of disease (but the extent of the increase ranges from a small to large amount) and an ABI within the normal range (≥0.90 and <1.3) does not exclude PAD. For toe‐brachial index (TBI), a threshold of <0.70 has a moderate ability to rule PAD in and out; however, this is based on limited evidence. Similarly, a small number of studies indicate that one or more monophasic Doppler waveforms in the pedal arteries is associated with the presence of PAD, whereas tri‐ or biphasic waveform suggests that PAD is less likely. Several forms of bedside testing may also be useful as adjunct tests and 7 studies were identified that investigated the reliability of bedside tests including ABI, toe pressure, TBI, transcutaneous oxygen pressure (TcPO2) and pulse palpation. Inter‐rater reliability was poor for pulse palpation and moderate for TcPO2. The ABI, toe pressure and TBI may have good inter‐ and intra‐rater reliability, but margins of error are wide, requiring a large change in the measurement for it to be considered a true change rather than error. There is currently no single bedside test or a combination of bedside tests that has been shown to have superior diagnostic accuracy for PAD in people with diabetes with or without DFU. However, an ABI <0.9 or >1.3, TBI of <0.70, and absent or monophasic pedal Doppler waveforms are useful to identify the presence of disease. The ability of the tests to exclude disease is variable and although reliability may be acceptable, evidence of error in the measurements means test results that are within normal limits should be considered with caution and in the context of other vascular assessment findings (e.g., pedal pulse palpation and clinical signs) and progress of DFU healing.

The intersocietal IWGDF, ESVS, SVS guidelines on peripheral artery disease in people with diabetes and a foot ulcer

“…The three systematic reviews previously mentioned provided the evidence for the graded recommendations made in this guideline. 5,6,7…”

“…[50][51][52][53] Although based on low quality evidence, data demonstrating increased likelihood of PAD in those with weak or absent pulses and elevated risk of cardiovascular morbidity and mortality support the preference of a person with diabetes for clinical examination including pulse palpation to be performed. 5,35 The non-invasive nature of clinical examination and pulse palpation suggest these assessments would be valued by people with diabetes as initial diagnostic tests. As equipment is not required, the Writing Committee considered pulse palpation and other forms of clinical examination having low resource requirements, can be applied on a broad scale by a range of practitioners, and offer a method to increase equity of health care access that is both feasible for health care providers and acceptable for people with diabetes.…”

“…The systematic review demonstrates that multiple bedside testing techniques that offer objective measurement of the peripheral circulation in the lower limb are useful as a means to rule disease in or out for people with diabetes without a DFU but who are suspected of having PAD. 5 Forty studies investigating the diagnostic accuracy of noninvasive bedside tests in populations with diabetes were identified. 5 Twenty-eight of the studies used prospective recruitment and the remainder were retrospective.…”

“…5 Forty studies investigating the diagnostic accuracy of noninvasive bedside tests in populations with diabetes were identified. 5 Twenty-eight of the studies used prospective recruitment and the remainder were retrospective. Overall, the studies were of low quality and evidence was judged as being of low certainty.…”

Practical guidelines on the prevention and management of diabetes‐related foot disease (IWGDF 2023 update)

“…We refer the reader for details and background to the different guidelines [1][2][3][4][5][6][7] and their underlying systematic reviews. [8][9][10][11][12][13][14][15][16][17][18] Should this summary text appear to differ from the information of any of these guidelines, we suggest the reader defers to that specific guideline. The seven evidence-based guidelines were developed following the GRADE methodology as described in a separate document.…”