P50 sensory gating in hypoxemic chronic obstructive pulmonary disease patients.

PURPOSE: Chronic obstructive pul- monary disease (COPD) is a condition character- ized by progressive airway obstruction and recur- rent attacks. Multisystem involvement with extra- pulmonary manifestations has been seen in COPD patients. Numerous neurological involvement like cerebrovascular diseases, polyneuropathies, motor neuron diseases and cognitive impairement has been reported in COPD patients. Cognitive dys- function is usually associated with hypoxia or hy- percapnia in COPD patients. To our knowledge there is no study about sensory gating in COPD pa- tients. We performed p50 test to COPD patients and we investigate sensory gating in COPD patients. PATIENTS AND METHODS: 25 male patients with COPD and 17 healthy male subjects for con- trols included to this study. The patients were di- agnosed with COPD according to the Global Initia- tive for Chronic Obstructive Lung Disease (GOLD) criteria. p50 amplitude and latency, percentage of P50 suppression, N100 amplitude and latency and the N100 suppression percentage of the COPD patients and controls presented were measured and compared. RESULTS: We found that the conditioning am- plitudes (S1) did not differ between COPD pa- tients and controls (p > 0.05) but (S2) amplitude was significantly increased in COPD patients (p < 0.05). COPD patients showed significantly low- er P50 and N100 suppression percentage than controls (p < 0.05). CONCLUSIONS: COPD patients showed a dis- turbance cognitive function such as attention with p50 suppression rate decrease. P50 senso- ry gating test can be useful to analyze the pre-at- tention period of cognitive impairment in the ear- ly phase of COPD patients.