Associations between pain, objective sleep efficiency and cognition in patients with implantable cardioverter defibrillators

Abnormal alterations of regional spontaneous neuronal activity and functional connectivity in insomnia patients with difficulty falling asleep: a resting-state fMRI study

BACKGROUND

Insomnia disorder (ID) seriously affects people's daily life. Difficulty falling asleep is the most commonly reported complaint in patients with ID. However, the mechanism of prolonged sleep latency (SL) is still obscure. The aim of our present study was to investigate the relationship between prolonged SL and alterations in spontaneous neural activity and brain functional connectivity (FC) in ID patients using functional magnetic resonance imaging (fMRI).

METHODS

A total of 52 insomniacs with difficulty falling asleep and 30 matched healthy controls (HCs) underwent resting-state fMRI. The amplitude of low-frequency fluctuation (ALFF) was measured and group differences were compared. The peak areas with significantly different ALFF values were identified as the seed regions to calculate FC to the whole brain. SL was assessed by a wrist actigraphy device in ID patients. The Pittsburgh Sleep Quality Index (PSQI), Hamilton Anxiety Rating Scale (HAMA), and Hyperarousal Scale (HAS) were evaluated in both ID patients and HCs. Finally, correlation analyses were performed between the clinical features and FC/ALFF values.

RESULTS

ID patients showed higher PSQI, HAMA, HAS scores than HCs. The functional MRI results indicated increased ALFF value in the left insula and right amygdala and decreased ALFF value in the right superior parietal lobe (SPL) in ID patients. The seed-based FC analysis demonstrated increased FC between the left insula and the bilateral precentral gyrus and FC between the right amygdala and the left posterior cingulate cortex (PCC) in patients with ID. Correlation analysis indicated that the increased FC value of the right amygdala-left PCC was positively correlated with SL measured by actigraphy.

CONCLUSION

This study revealed abnormal regional spontaneous fluctuations in the right amygdala, left insula, and right SPL, as well as increased FC in the left insula-precentral and right amygdala-left PCC. Moreover, the prolonged SL was positively correlated with the abnormal FC in the right amygdala-left PCC in ID patients. The current study showed the correlation between prolonged SL and the abnormal function of emotion-related brain regions in ID patients, which may contribute to a better understanding of the neural mechanisms underlying difficulty falling asleep in patients with ID.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn ., ChiCTR1800015282. Registered on 20th March 2018.

Using Consumer-Wearable Activity Trackers for Risk Prediction of Life-Threatening Heart Arrhythmia in Patients with an Implantable Cardioverter-Defibrillator: An Exploratory Observational Study

Ventricular arrhythmia (VA) is a leading cause of sudden death and health deterioration. Recent advances in predictive analytics and wearable technology for behavior assessment show promise but require further investigation. Yet, previous studies have only assessed other health outcomes and monitored patients for short durations (7−14 days). This study explores how behaviors reported by a consumer wearable can assist VA risk prediction. An exploratory observational study was conducted with participants who had an implantable cardioverter-defibrillator (ICD) and wore a Fitbit Alta HR consumer wearable. Fitbit reported behavioral markers for physical activity (light, fair, vigorous), sleep, and heart rate. A case-crossover analysis using conditional logistic regression assessed the effects of time-adjusted behaviors over 1−8 weeks on VA incidence. Twenty-seven patients (25 males, median age 59 years) were included. Among the participants, ICDs recorded 262 VA events during 8093 days monitored by Fitbit (median follow-up period 960 days). Longer light to fair activity durations and a higher heart rate increased the odds of a VA event (p < 0.001). In contrast, lengthier fair to vigorous activity and sleep durations decreased the odds of a VA event (p < 0.001). Future studies using consumer wearables in a larger population should prioritize these outcomes to further assess VA risk.

Preliminary investigation of interactive associations of sleep and pain with cognition in sedentary middle-aged and older adults

STUDY OBJECTIVES

The objective of this study was to examine independent and interactive associations between self-reported sleep (sleep efficiency and total sleep time [TST]) and pain with cognition in sedentary middle-aged and older adults.

METHODS

Seventy-five sedentary adults at least 50 years of age (Mage = 63.24, standard deviation = 8.87) completed 14 daily diaries measuring sleep and pain. Weekly average sleep efficiency, TST, and pain were computed. Participants also completed computerized cognitive tasks: Letter Series (reasoning), N-back (working memory), Symbol Digit Modalities Test (processing speed, attention), and Number Copy (processing speed). Multiple regression analyses were conducted to determine independent and interactive (with pain) associations of sleep efficiency and TST with cognition, controlling for age, education, and sex.

RESULTS

Sleep efficiency and pain interacted in their associations with Letter Series performance and N-back difference scores (2-back minus 1-back). Specifically, higher sleep efficiency was associated with better reasoning and working memory in those with highest pain but not average or lowest pain. TST and pain also interacted in their associations with Letter Series performance. Specifically, longer TST associated with worse reasoning in those with lowest (not average or highest) pain.

CONCLUSIONS

Preliminary results show that in sedentary middle-aged and older adults, pain and sleep interact in their associations with executive function tasks. Higher sleep efficiency may be associated with better reasoning and working memory in those with highest pain. Lower TST may be associated with better reasoning in those with lowest pain. Studies evaluating temporal associations between sleep, pain, and cognition are needed.