The Pain in Neuropathy Study (PiNS)

Abstract

Supplemental Digital Content is Available in the Text.The Pain in Neuropathy Study (PiNS), an observational cross-sectional multicentre study, demonstrated a positive correlation between greater diabetic neuropathy severity and the presence and severity of neuropathic pain.

New Horizons in Diabetic Neuropathy: Mechanisms, Bioenergetics, and Pain

“…Results show that increased sensitivity to mechanical and thermal stimuli are the best discriminating features between DN patients with and without neuropathic pain (Scholz et al, 2016). It is possible that the dominance of sensory loss versus the presence of hyperalgesia and allodynia (Maier et al, 2010; Themistocleous et al, 2016) may explain the failure to find clear distinguishing features in painful versus painless DN.…”

“…There may be some relatively simple explanations for the development of neuropathic pain that relate to the degree of the inciting lesion to the somatosensory nervous system. For example, there is a positive correlation between both neuropathy severity and poor glycemic control with both the risk and intensity of neuropathic pain (Themistocleous et al, 2016); however, this is by no means a linear relationship, and there are patients with severe neuropathy who never develop pain. In relation to genetic predisposition, data are now emerging (discussed below) that certain ion channel variants may predispose to the development of painful DN.…”

The Potential Role of Sensory Testing, Skin Biopsy, and Functional Brain Imaging as Biomarkers in Chronic Pain Clinical Trials: IMMPACT Considerations

“…It has therefore been hypothesized that neuropathic pain is generated not by a single mechanism, but rather by multiple mechanisms operating in concert that lead to phenotypic heterogeneity and potentially to differential treatment response [14]. For example, well-characterized neuropathic pain conditions such as postherpetic neuralgia (PHN; [59]), diabetic peripheral neuropathy (DPN; [179]), and trigeminal neuralgia [124] all contain multiple subgroups identified using quantitative sensory testing (QST)-based sensory profiling.…”

“…Individuals with FM have been shown to have abnormal thresholds for heat and cold pain compared with healthy controls [88, 186], as well as distinct sensory profiles compared with individuals with CLBP [23]. QST testing using the DFNS protocol found a loss of function in cold detection, mechanical detection, and vibration detection thresholds among individuals with moderate to severe DPN pain compared with the normative ranges for healthy controls [179]. In this same study, a greater loss of function was seen in 3 out of 6 of the thermal QST parameters, as well as in the mechanical detection threshold, among individuals with moderate to severe DPN pain compared with individuals with painless DPN [179].…”

“…They also demonstrated high sensitivity and specificity in diagnosing polyneuropathy using a clinician diagnosis as the reference standard when IENFD and epidermal nerve fiber length densities were combined [95]. However, recent results from an observational study showed no differences in IENFD between individuals with painful and painless DPN [179]. …”