Neurologic Manifestations of Lung Disease

The neurologic changes seen in association with or as a result of lung diseases are quite variable, ranging from the changes associated with abnormal gas exchange, paraneoplastic syndrome, direct effects of metastatic cancers, to the changes resulting from the treatment of the underlying lung diseases, such as mechanical ventilation or use of pharmacologic agents. The neurologic changes may also result from secondary complications of the primary lung disease, such as infections, nutritional and vascular diseases. Occasionally the neurologic and the pulmonary systems are simultaneously involved by the same disease process, such as systemic lupus erythematosus. This review will focus on the neurologic changes resulting from abnormalities of gas exchange in chronic respiratory insufficiency and obesity hypoventilation. Also, the neurologic changes of paraneoplastic and neurometabolic syndromes will be reviewed in depth. Table 1 enumerates the other pulmonary conditions associated with neurologic changes and the reader is referred to the references for a more in-depth review.