Somatosensory profiling of patients undergoing alcohol withdrawal: do neuropathic pain and sensory loss represent a problem?

Chronic heavy alcohol use is known to cause neurological complications such as peripheral neuropathy. Concerning the pathophysiology, few sural nerve and skin biopsies studies showed that small fibers might be selectively vulnerable to degeneration in alcohol-related peripheral neuropathy. Pain has rarely been properly evaluated in this pathology. The aim of the present study was to assess pain intensity, potential neuropathic characteristics as well as the functionality of both small and large nerve sensitive fibers.

In this observational study, twenty-seven consecutive adult patients, hospitalized for alcohol withdrawal and 13 healthy controls were recruited. All the participants underwent a quantitative sensory testing (QST) according to the standardized protocol of the German Research Network Neuropathic Pain, a neurological examination and filled standardized questionnaires assessing alcohol consumption and dependence as well as pain characteristics and psychological comorbidities.

Half of the patients reported pain. Yet the intensity was weak, leading to a low interference with daily life, and the characteristics did not support a neuropathic component. A functional impairment of small nerve fibers was frequently described, with thermal hypoesthesia observed in 52% of the patients. Patients with a higher alcohol consumption over the last 2 years showed a greater impairment of small fiber function.