Circadian Variation of Core Body Temperature in Parkinson Disease Patients with Depression: A Potential Biological Marker for Depression in Parkinson Disease

Abstract

Background: The biological rhythm in comorbidity of depression and Parkinson disease (PD) is still unclear. For early diagnosis or clarification of the pathologic condition of comorbidity of depression and PD, the present study investigated the presence of circadian rhythm abnormalities in patients with depression. Methods: We measured the rectal temperature (RT) in 30 PD patients with or without depression during 48 consecutive hours using the maximum entropy method (MEM) and least-squares method (COSINOR). The presence of major or minor depression was evaluated by the Mini International Neuropsychiatric Interview based on the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders, and the Hamilton Depression Scale. Results: The RT rhythms of patients without depression predominately showed a circadian rhythm. However, 2 of 6 patients with depression showed an infradian rhythm using MEM. COSINOR revealed that PD patients with depression showed lower amplitudes of core body temperature (p = 0.012) and higher minimum RT (p = 0.031) relative to those of patients without depression. Conclusion: PD patients with depression show an altered RT circadian rhythm. The results suggest that the characteristics of core body temperature could be potentially used as a biological marker for depression in PD.