The Characterization of Biological Rhythms in Mild Cognitive Impairment

Abstract

Introduction. Patients with dementia, especially Alzheimer's disease, present several circadian impairments related to an accelerated perturbation of their biological clock that is caused by the illness itself and not merely age-related. Thus, the objective of this work was to elucidate whether these circadian system alterations were already present in patients with mild cognitive impairment (MCI), as compared to healthy age-matched subjects. Methods. 40 subjects (21 patients diagnosed with MCI, 74.1 ± 1.5 y.o., and 19 healthy subjects, 71.7 ± 1.4 y.o.) were subjected to ambulatory monitoring, recording wrist skin temperature, motor activity, body position, and the integrated variable TAP (including temperature, activity, and position) for one week. Nonparametrical analyses were then applied. Results. MCI patients exhibited a significant phase advance with respect to the healthy group for the following phase markers: temperature M5 (mean ± SEM: 04:20 ± 00:21 versus 02:52 ± 00:21) and L10 (14:35 ± 00:27 versus 13:24 ± 00:16) and TAP L5 (04:18 ± 00:14 versus 02:55 ± 00:30) and M10 (14:30 ± 00:18 versus 13:28 ± 00:23). Conclusions. These results suggest that significant advances in the biological clock begin to occur in MCI patients, evidenced by an accelerated aging of the circadian clock, as compared to a healthy population of the same age.

Circadian monitoring as an aging predictor

“…The DST rhythm showed a pattern similar to that previously described for these populations 22 , 26 , 27 . Thus, young participants had a marked wake maintenance zone in the evening 22 , 24 , 28 , both for arousal 29 , 30 and DST 22 .…”

Sleep problems in adults with autism spectrum disorder and intellectual disability

“…Phase advance in our sample with ASD is also evidenced with phase markers L5 and M10 and lower TAP values registered from midday until midnight. Our TAP rhythm in ASD matched that described for circadian rhythm alterations in mild cognitive impairment [Ortiz‐Tudela, Martinez‐Nicolas, Díaz‐Mardomingo, et al, ]. The light intensity values recorded in the ASD sample were significantly higher in the morning and more robust during the week, according to the greater CFI value found.…”

“…Third, ACM has not been validated in ASD to study sleep and this is the first study that has used this device to assess sleep in autistic individuals; however ACM has been shown to give rise to more accurate results than actigraphy [Ortiz‐Tudela, Martinez‐Nicolas, Albares, et al, ]. Furthermore, this device has shown its effectiveness for assessing sleep in individuals with Parkinson [Madrid‐Navarro et al, ], mild cognitive impairment [Ortiz‐Tudela et al, ], or critically ill confined participants [Madrid‐Navarro et al, ]. Furthermore, the algorithms used by actigraphy devices to predict sleep periods are sometimes designed for specific populations, which could impair the proper detection of sleep in groups with different conditions [Sadeh & Acebo, ; Insana, Gozal, & Montgomery‐Downs, ]; however, the TAP variable predicts rest‐activity periods with high accuracy and independently from conditions that participants may have [Ortiz‐Tudela et al, ].…”

24-h Activity Rhythms and Health in Older Adults

“…This was even though the latter was found to be disturbed in those with Alzheimer's disease [30]. In contrast, some earlier studies have reported a phase advance in persons with mild cognitive impairment compared with healthy controls [36,37] and a higher fragmentation and lower mesor in those with preclinical AD [16]. Data from prospective cohorts provide some further insight into the temporality of the association of 24-h activity rhythms with dementia.…”