Optimism and Sleep in Aging Women: Bidirectional Relationships.

OBJECTIVE: Sleep quality and duration are important for biological restoration and promotion of psychological well-being. Optimism may facilitate or result from sufficient sleep, but questions remain as to directionality. The present study tested how optimism is associated with levels of and variability in sleep quantity and quality in a longitudinal burst design. METHODS: Midlife and older women ( N = 199) reported their sleep quantity and quality in online diaries for a 7-day period, every 3 months for 2 years. Optimism was measured at baseline and end-of-study. Multilevel models tested the effects of optimism on sleep. Linear regression models tested the effect of sleep on optimism. RESULTS: Baseline optimism was associated with higher sleep quality ( γ = 2.13 [1.16 to 3.11], p < .0001) and lower intraindividual variability (IIV; night-to-night and wave-to-wave) in sleep quantity (night-to-night: γ = -0.07 [-0.13 to -0.005], p = .03; wave-to-wave: b = -0.07 [-0.12 to -0.02], p = .003). In turn, higher average sleep quality (but not quantity) was associated with higher optimism at end-of-study ( b = 0.02 [0.007 to 0.03], p = .002). Variability in sleep was unrelated to optimism. CONCLUSIONS: Optimism may play an important role in maintaining sleep quality and consistency in sleep quantity, perhaps by buffering stress. Similarly, sleep quality may play an important role in maintaining optimism. The cycle whereby optimism and sleep enhance one another could improve physical health and psychological well-being among aging adults.

Diagnostic accuracy of a portable device (Bruxoff®) to measure sleep bruxism.

BACKGROUND: Diagnosis of sleep bruxism (SB) challenges clinicians every day due to multiple forms of assessment tools available, including self-reported questionnaires, clinical examinations, portable devices and laboratory polysomnography (PSG). PSG has become the gold standard for evaluating SB, but it can be limited due to cost and restricted accessibility which often is characterised by long waiting times. Hence, there is a need for the development of a reliable method that can assess SB in a simple and portable manner, which would offer acceptable sensitivity and specificity to evaluate SB. OBJECTIVE: The objective of this study was to investigate reliability and validity of the Bruxoff® device for the diagnosis of SB compared to the PSG. METHODS: Forty-nine subjects underwent one night of polysomnographic study with simultaneous recording with the Bruxoff® device. Rhythmic masticatory muscle activity (RMMA) index was scored according to published criteria. Pearson correlation, Bland-Altman plot and receiver operating characteristic (ROC) curve outcomes were used to quantify the agreement between both methods. RESULTS: Receiver operating characteristic analysis showed an acceptable accuracy for the Bruxoff® with sensitivity of 83.3% and specificity of 72% when the cut-off was set at two events per hour. Pearson correlation analysis showed a nearly significant correlation between PSG and Bruxoff® for RMMA index (r = .282 p = .071) and for total SB episodes per night (r = .295 p = .058). Additionally, the Bland-Altman plot revealed a consistent and systematic difference in the measurement of events between devices. CONCLUSION: The Bruxoff® device appears to be a promising diagnostic method for clinical use, but further study is needed.

Association Between Urine Output and Mortality in Critically Ill Patients: A Machine Learning Approach.

OBJECTIVES: Current definitions of acute kidney injury use a urine output threshold of less than 0.5 mL/kg/hr, which have not been validated in the modern era. We aimed to determine the prognostic importance of urine output within the first 24 hours of admission to the ICU and to evaluate for variance between different admission diagnoses. DESIGN: Retrospective cohort study. SETTING: One-hundred eighty-three ICUs throughout Australia and New Zealand from 2006 to 2016. PATIENTS: Patients greater than or equal to 16 years old who were admitted with curative intent who did not regularly receive dialysis. ICU readmissions during the same hospital admission and patients transferred from an external ICU were excluded. MEASUREMENTS AND MAIN RESULTS: One hundred and sixty-one thousand nine hundred forty patients were included with a mean urine output of 1.05 mL/kg/hr and an overall in-hospital mortality of 7.8%. A urine output less than 0.47 mL/kg/hr was associated with increased unadjusted in-hospital mortality, which varied with admission diagnosis. A machine learning model (extreme gradient boosting) was trained to predict in-hospital mortality and examine interactions between urine output and survival. Low urine output was most strongly associated with mortality in postoperative cardiovascular patients, nonoperative gastrointestinal admissions, nonoperative renal/genitourinary admissions, and patients with sepsis. CONCLUSIONS: Consistent with current definitions of acute kidney injury, a urine output threshold of less than 0.5 mL/kg/hr is modestly predictive of mortality in patients admitted to the ICU. The relative importance of urine output for predicting survival varies with admission diagnosis.

Optimism and Pain Interference in Aging Women.

BACKGROUND: Pain interferes with people's daily lives and often limits the extent to which they can pursue goals and engage in activities that promote well-being. However, people vary in how much interference they experience at a given level of pain. PURPOSE: The present study tested how optimism affects and is affected by pain interference and goal-directed activity among older women. METHODS: Every 3 months for 2 years, community-dwelling middle- and older-age women (N = 199) completed online daily diaries at home for a 7 day period, in which they reported their daily pain, pain interference, and goal-directed activity. Optimism was measured at the start and end of the study. Multilevel models tested the between- and within-person relationships among pain, optimism, and pain interference or goal-directed activity. Linear regression predicted change in optimism over 2 years from pain interference and goal-directed activity. RESULTS: Pain best predicted pain interference and optimism best predicted goal-directed activity. There were subtle interactions between optimism and pain-predicting interference and goal-directed activity. Accumulated goal-directed activity and pain interference across the study predicted longitudinal changes in optimism, with higher activity and lower pain interference predicting increased optimism over 2 years. CONCLUSIONS: Optimism may play a protective role in disruptions caused by pain on a day-to-day basis, leading to increased goal-directed activity and possibly decreased pain interference. In turn, less interference and more goal-directed activity feed forward into increased optimism, resulting in a virtuous cycle that enhances optimism and well-being among older women.

Conscientiousness and Pain Interference in Older Age.

OBJECTIVES: Conscientiousness is associated with positive health behaviors and outcomes and has been shown to increase as individuals age. Both age and Conscientiousness affect pain, a highly prevalent correlate of aging. This study investigated the effect of Conscientiousness on the relationship between pain and pain interference and vice versa among older adults, who experience pain and functional limitations disproportionately compared with younger adults. METHODS: A total of 196 community-dwelling older adults (Mage = 73) provided pain and interference ratings semiannually for up to 10 years. Conscientiousness was assessed at the first visit and, on average, 7.6 years later. Multilevel models tested the effect of Conscientiousness on the relationship between pain and interference. Hierarchical regression modeled changes in Conscientiousness. RESULTS: Across all pain levels, higher Conscientiousness was associated with less pain interference (γ02 = -0.126, SE = 0.048, p < .01, 95% confidence intervals (95% CI) [-0.22, -0.03]). This effect was more pronounced at higher levels of pain and older age. Conscientiousness increased slightly over time, but older baseline age (b = -0.01, 95% CI [-0.03, -0.001], R2 = 0.02) and more mean pain interference over the study period (b = -0.17, 95% CI [-0.30, -0.03], R2 = 0.03) were associated with less increase in Conscientiousness at follow-up. DISCUSSION: Higher pain and older age are associated with more pain interference, and Conscientiousness provided the most protection for these same individuals-those with higher pain and older age. Conscientiousness facilitated reduced interference, which may feed forward into higher Conscientiousness, potentially shaping a cycle between personality and health that extends through older adulthood.

The role of late-differentiated T cells, a proxy for IFN-γ-production, in older adults' social networks.

Interferon-γ (IFN-γ), an inflammatory biomarker that promotes antiviral immunity, may be a prerequisite for sociability. IFN-γ production in older adulthood is driven by late-differentiated CD8+ T cells, particularly CD28-and CD57+ subsets, which increase with age, reduce immune response, and increase chronic disease risk. The present study investigated the relationship between late-differentiated T cells (LDTC) and sociability in a longitudinal study of healthy aging. 139 older adults (Mage = 77.95, range 65-93; 58% female, 57% college educated, and 94% Caucasian) provided data at up to 10 occasions (M = 7). Social network size and diversity and cytomegalovirus (CMV) status were collected at every wave. Percentage of LDTC was measured at up to 4 waves and averaged for each participant. There were no significant main effects of LDTC or interactions between LDTC and time on social network size or diversity. Adjustment for baseline age, gender, and sensitivity analyses including CMV and imputed data did not change results. IFN-γ may not play a role in dictating social behavior in older adults. Alternately, LDTC may not have accurately represented circulating levels of IFN-γ. Future work should continue exploring IFN-γ and social behavior, particularly as it relates to age-related changes. The role of IFN-γ-producing, late-differentiated T cells in older adults' social networks.