Educate Diabetes Patients to Test at Home

FOR THE FUTURE

How The Standard, ADA Recommended, Test Could be superseded at home to offer an even earlier warning with C-PAC

At home Self-Testing Technique – The Diabetic Toes Test – utilizes a single application sufficient to indent the skin producing a simple, ‘binary’, yes/no response – sharp or not. This technique is a crude comparison designed to reveal only when sensation has deteriorated so far that patients can’t distinguish between a feeling of sharp or blunt. It represents the current standard recommended by the ADA but, inevitably, detects only extreme loss and higher ulceration risk. Very reliable, if a crude measure is the only requirement, but not the best option as an early warning.

Continuous Analogue Pinprick Comparison (C-PAC) testing which seeks to quantify similarity in pinprick sensitivity between a ‘normal’ control area – such as the palmer side of the wrist - and that of the periphery (foot) by means of a Verbal Analogue Scale. In this case the patient uses pinprick to establish and ascribe an arbitrary numerical value of 5/10 to the sensation in the area representing their ‘normal’, which can be compared to the foot. The foot should feel the same as the wrist and subtle deterioration will be detected easily and quantified on the same scale. By recording the result monthly the patient can track any gradual loss over time.

This CPC/PAC test technique has so far been directed at clinicians only because it is more complex to perform though, logically, is consistent with justifiable evidence based physiology and is easily grasped where there is sufficient understanding. In order to introduce this to the patient population a stronger base of practical evidence would be helpful and this is to be gained through a pertinent study at an appropriate centre of excellence.

The ADA technique is simple and easy to convey to patients but ironically, not very compelling. It belongs to a group of 5 tests recommended by a specialist panel of experts who, themselves, subscribe to and promote, the current mood of professional controversy regarding the limitations to these and other tests in general which are claimed to achieve the same thing, It is, at best, for both the ADA and us, a compromise. In short it is simply our ‘safe’ and defensible option in that it is recognised and advocated but, when performed exactly as the ADA instructs, not that efficacious. More ironic is it that, despite being virtually unknown within the relevant healthcare professions, the available evidence strongly suggests even the ADA’s crude version of pinprick testing is, in all probability, superior to other tests recommended in the same group.

The actual revelation will be to utilise the conclusions from the completed C-PAC study for home testing. If the instructions can be conveyed simply to the home user there would suddenly be to hand a significantly more potent and logically compelling testing option where patients can really gauge their vulnerability risk dictated by pinprick integrity. Pinprick really is best for the verbal analogue scale as years of research show us.

It just can’t be done easily with alternative modalities, including monofilament and the sensory loss it detects develops earlier. Patients will be able to track their progress over the year with greater precision using a better-informed system for anticipating the development of increasing risk of ulceration - an even more reliable early warning. A patient performing the C-PAC technique routinely may produce a calendar as below: