Nocturnal body core temperature falls in Parkinson's disease but not in multiple-system atrophy

Objective: To evaluate whether the circadian rhythm of body core temperature (CRT°) can differentiate Multiple-System Atrophy (MSA) from Idiopathic Parkinson's disease (IPD). Methods: We evaluated 14 patients with probable MSA, seven with IPD, and eight controls. After a preliminary evaluation of cardiovascular autonomic function, rectal temperature and sleep-wake cycle were monitored continuously for 48 hours in a temperature-controlled room, at constant bed rest with controlled food intake and fixed light-dark schedule. Results: MSA patients showed cardiovascular autonomic sympathetic and parasympathetic failure. IPD had normal cardiovascular autonomic function. A 24-hour rhythm of body core temperature (BcT°) was present in all subjects. IPD had CRT° comparable to controls. In MSA the mesor was higher and mean BcT° of each hour was significantly higher from 11 p.m. to 7 a.m. The analysis of mean BcT° during the different sleep phases showed significantly higher values during both NREM (1-2, 3-4) and REM sleep stages in MSA. Conclusions: The physiological nocturnal fall of BcT° is blunted in MSA patients mainly because BcT° did not decrease during sleep. This CRT° pattern is not justified by differences in sleep structure and may reflect an impairment of central sympathetic nervous system function.