Adrenal dysregulation in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a chronic progressive neuromuscular disorder of unknown etiology, characterized by weakness, muscle wasting, fasciculations and increased reflexes, with conserved intellect and higher function. The disease is due to degeneration of the motor neurons in the cerebral cortex, brainstem nuclei and anterior horns of the spinal cord. Although ALS poses an extreme burden on individual condition, data are missing concerning the regulation of adrenal function in the disease. In the present study we investigated cortisol levels in saliva of ALS patients as compared to healthy subjects. The results showed the loss of circadian rhythm of cortisol levels in ALS; in particular, levels of cortisol in the evening sample were significantly increased in ALS patients with respect to controls. Moreover, ALS patients did not show any physiological increase of cortisol levels following an unexpected mild stress (color-word Stroop test). These findings indicate the dysregulation of adrenal activity in the disease.