Association Between Severe Chronic Obstructive Pulmonary Disease and Polyneuropathy

BACKGROUND Chronic obstructive pulmonary disease (COPD) is a life-threatening and devastating disease associated with low-grade systemic inflammation. In adults, the most common disease of the peripheral nervous system is peripheral neuropathy. While most polyneuropathy has a mixed presentation, some cases are motor dominant and others are sensory dominant. We investigated polyneuropathy in patients with COPD and hypothesized that low-grade systemic inflammation and other pathologies in patients with COPD cause peripheral axonal polyneuropathy. MATERIAL AND METHODS We included 62 patients with COPD without any neurological signs or symptoms, and 30 healthy volunteers with no known neurological or pulmonary diseases as controls. There were 38 men in the COPD group and 17 men in the control group; the mean ages of the 2 groups were 64.88 and 62.7 years, respectively. According to the Global Initiative for Chronic Obstructive Lung Disease COPD report, all COPD patients were group D. After collecting demographic and clinical characteristics of the participants, we performed an electrophysiological examination to investigate polyneuropathy and pulmonary function test results. C-reactive protein, hemoglobin, creatinine, partial carbon dioxide pressure (pCO₂) levels were recorded. Electrophysiological examination was performed with a Medelec Synergy device using standard neurographic procedures, and the results were assessed. RESULTS Significant differences were found for forced expiratory volume in 1 sec (FEV1), %FEV1, forced vital capacity (FVC), %FVC, pCO₂, and hemoglobin and creatinine levels, but all participants had a creatinine level within the normal range. There was no difference in sensory neuropathy between the groups, but a significant difference was found in terms of motor neuropathy. CONCLUSIONS As noted in previous studies, systemic inflammation, increased oxidative stress, decreased oxygen pressure, and multiple comorbidities in patients with COPD may all contribute to the development of neuropathy.