Publications

Visible light is the principal stimulus for resetting the mammalian central circadian pacemaker. Circadian phase resetting is most sensitive to short-wavelength (blue) visible light. We examined the effects of removing short-wavelengths < 500 nm from polychromatic white light using optical filters on circadian phase resetting in rats. Under high irradiance conditions, both long- (7 h) and short- (1 h) duration short-wavelength filtered (< 500 nm) light exposure attenuated phase-delay shifts in locomotor activity rhythms by (∼40-50%) as compared to unfiltered light exposure. However, there was no attenuation in phase resetting under low irradiance conditions. Additionally, the reduction in phase-delay shifts corresponded to regionally specific attenuation in molecular markers of pacemaker activation in response to light exposure, including c-FOS, Per1 and Per2. These results demonstrate that removing short-wavelengths from polychromatic white light can attenuate circadian phase resetting in an irradiance dependent manner. These results have important implications for designing and optimizing lighting interventions to enhance circadian adaptation.

STUDY OBJECTIVES: The Menopause Strategies: Finding Lasting Answers for Symptoms and Health network conducted three randomized clinical trials (RCTs) testing six interventions treating vasomotor symptoms (VMS), and also collected self-reported sleep outcomes. A fourth RCT assessed an intervention for insomnia symptoms among women with VMS. We describe these seven interventions' effects relative to control in women with comparably severe insomnia symptoms and VMS.

METHODS: We analyzed pooled individual-level data from 546 peri- and postmenopausal women with Insomnia Severity Index (ISI) ≥ 12, and ≥14 bothersome VMS/week across the four RCTs. Interventions included the following: escitalopram 10-20 mg/day; yoga; aerobic exercise; 1.8 g/day omega-3 fatty acids; oral 17-beta-estradiol 0.5-mg/day; venlafaxine XR 75-mg/day; and cognitive behavioral therapy for insomnia (CBT-I). Outcome measures were ISI and Pittsburgh Sleep Quality Index (PSQI) over 8-12 weeks of treatment.

RESULTS: CBT-I produced the greatest reduction in ISI from baseline relative to control at -5.2 points (95% CI -7.0 to -3.4). Effects on ISI were similar for exercise at -2.1 and venlafaxine at -2.3 points. Comparably small decreases in ISI were observed with escitalopram, yoga, and estradiol. The largest reduction in PSQI from baseline was with CBT-I at -2.7 points (-3.9 to -1.5), although PSQI decreases of 1.2 to 1.6 points were significantly better than control with escitalopram, exercise, yoga, estradiol, and venlafaxine. Omega-3 supplements did not improve insomnia symptoms.

CONCLUSIONS: This study's findings support current recommendations for CBT-I as a first line treatment in healthy midlife women with insomnia symptoms and moderately bothersome VMS.

Accumulating evidence points to a genetic contribution to explain inter-individual vulnerability to sleep deprivation. A functional polymorphism in the BDNF gene, which causes a valine (Val) to methionine (Met) amino acid substitution at Codon 66, has been associated with cognitive impairment, particularly in populations with impaired frontal functioning. We hypothesised that sleep deprivation, which affects frontal function, may lead to cognitive dysfunction in Met allele carriers. To examine this, we investigated, in different BDNF genotypes, the effects of sleep deprivation on cognitive flexibility, as measured by response inhibition using the Stroop Color Naming Task. Thirty healthy, adults of European ancestry, including 12 heterozygous Met allele carriers and 18 Val/Val homozygotes, underwent 30-h of extended wakefulness under constant routine conditions. A computerised Stroop task was administered every 2h. Error rate and reaction times increased with time awake for all individuals. Participants with the Val/Met genotype made more errors on incongruent trials after 20h awake. While Val/Met participants also took significantly longer to respond when inhibiting a prepotent response irrespective of time awake, this was particularly evident during the biological night. Our study shows that carriers of the BDNF Met allele are more vulnerable to the impact of prolonged wakefulness and the biological night on a critical component of executive function, as measured by response inhibition on the Stroop task.

KEY POINTS: There is assumed to be a monotonic association between melatonin suppression and circadian phase resetting induced by light exposure. We tested the association between melatonin suppression and phase resetting in humans. Sixteen young healthy participants received nocturnal bright light (∼9500 lux) exposure of continuous or intermittent patterns, and different durations ranging from 12 min to 6.5 h. Intermittent exposure patterns showed significant phase shifts with disproportionately less melatonin suppression. Each and every bright light stimulus in an intermittent exposure pattern induced a similar degree of melatonin suppression, but did not appear to cause an equal magnitude of phase shift. These results suggest that phase shifts and melatonin suppression are functionally independent such that one cannot be used as a proxy measure of the other.

ABSTRACT: Continuous experimental light exposures show that, in general, the conditions that produce greater melatonin suppression also produce greater phase shift, leading to the assumption that one can be used as a proxy for the other. We tested this association in 16 healthy individuals who participated in a 9-day inpatient protocol by assessing melatonin suppression and phase resetting in response to a nocturnal light exposure (LE) of different patterns: (i) dim-light control (<3 lux; n = 6) or (ii) two 12-min intermittent bright light pulses (IBL) separated by 36 min of darkness (∼9500 lux; n = 10). We compared these results with historical data from additional LE patterns: (i) dim-light control (<3 lux; n = 11); (ii) single continuous bright light exposure of 12 min (n = 9), 1.0 h (n = 10) or 6.5 h (n = 6); or (iii) an IBL light pattern consisting of six 15-min pulses with 1.0 h dim-light recovery intervals between them during a total of 6.5 h (n = 7). All light exposure groups had significantly greater phase-delay shifts than the dim-light control condition (P < 0.0001). While a monotonic association between melatonin suppression and circadian phase shift was observed, intermittent exposure patterns showed significant phase shifts with disproportionately less melatonin suppression. Each and every IBL stimulus induced a similar degree of melatonin suppression, but did not appear to cause an equal magnitude of phase shift. These results suggest unique specificities in how light-induced phase shifts and melatonin suppression are mediated such that one cannot be used as a proxy measure of the other.

OBJECTIVE: HIV-infected women are burdened by depression and anxiety, which may impact adherence to antiretroviral therapy and overall quality of life. Yet, little is known about the scope of psychological symptoms in the growing number of HIV-infected women reaching menopause, when affective symptoms are more prevalent in the general population. We conducted a longitudinal study to compare affective symptoms between perimenopausal HIV-infected and non-HIV-infected women.

METHODS: The Center for Epidemiologic Studies Depression Scale (CES-D), and the Generalized Anxiety Disorder scale (GAD-7) were completed at baseline and 12 months among 33 HIV-infected and 33 non-HIV-infected perimenopausal women matched by race, age, menstrual patterns, and BMI. Linear regression models estimated the relationship of baseline GAD-7 and CES-D scores with clinical factors.

RESULTS: All women were perimenopausal at baseline, and the vast majority remained perimenopausal throughout follow-up. HIV status was associated with higher baseline CES-D scores (median [interquartile range] 21 [12, 29] vs 10 [5, 14]; P = 0.03) and GAD-7 scores (7 [5, 15] vs 2 [1, 7]; P = 0.01), controlling for smoking, substance use, and antidepressant use. Depressive symptoms and anxiety remained significantly higher in the HIV-infected women at 12 months (P ≤ 0.01). Significant relationships of depressive symptoms (P = 0.048) and anxiety (P = 0.02) with hot flash severity were also observed.

CONCLUSIONS: Perimenopausal HIV-infected women experienced a disproportionately high level of affective symptom burden over a 12-month observation period. Given the potential for these factors to influence adherence to HIV clinical care and quality of life, careful assessment and referral for treatment of these symptoms is essential.

OBJECTIVE: The aim of the study was to identify associations between improvement in genitourinary symptoms of menopause (GSM) and vaginal microbiota, vaginal glycogen, and serum estrogen.

METHODS: Thirty postmenopausal women enrolled in a hot flash treatment trial (oral estradiol vs venlafaxine vs placebo) who reported GSM and provided vaginal swabs at 0, 4, and 8 weeks were studied. Bacterial communities were characterized using deep sequencing targeting the 16S rRNA gene V3-V4 region. Participants selected a most bothersome genitourinary symptom (dryness, discharge, pain, itch/burn, or inability to have sex) and rated severity on a 10-point scale at baseline and 8 weeks. Vaginal glycogen and serum estradiol and estrone were measured at enrollment and 8 weeks. Comparisons according to improvement in most bothersome symptom (MBS) were made using χ, Wilcoxon signed-rank test, or Hotelling's t test.

RESULTS: Of 30 participants, 21 (70%) had improvement in MBS over the 8-week study and 9 (30%) had no improvement or worsening of MBS. A higher proportion of women receiving estradiol or venlafaxine reported improvement in MBS (88%, 78%) compared with placebo (54%; P = 0.28). MBS improvement was associated with Lactobacillus-dominant vaginal microbiota at enrollment (57% vs 22%, P = 0.08). Vaginal glycogen, serum estradiol, and estrone significantly increased in women whose MBS improved.

CONCLUSIONS: A larger proportion of women whose MBS improved had a Lactobacillus dominant microbiota at enrollment than those who had no improvement during the trial, though this difference was not statistically significant. Larger trials are needed to determine whether vaginal microbiota modify or mediate treatment responses in women with GSM.

Parenting children with conduct problems (CP) is challenging, yet very little is known about the impact of the child's behaviour on family functioning or how parents of children with CP perceive their child. The aim of this research was to examine whether families with children with CP and high vs. low levels of callous-unemotional traits (HCU vs. LCU) experience differences in family functioning and parental perceptions. One hundred and one parents/caregivers of boys aged 11-16 [Typically developing (TD) n = 31; CP/HCU n = 35; CP/LCU n = 35] completed the McMaster Family Assessment Device, measuring multiple domains of family functioning. Parents/caregivers also completed a written statement describing their child, used for qualitative analysis. Families with CP/HCU children had poorer affective involvement than TD (p = 0.00; d = - 1.17) and CP/LCU (p = 0.03; d = - 0.62) families. Families with CP/HCU children showed significantly poorer general family functioning (p = 0.04; d = - 0.63) and more poorly defined family roles (p = 0.005; d = - 0.82) than families with TD children. Qualitative analyses indicated that parents/caregivers of CP/HCU children characterised them as having a dichotomous personality and being superficially charming. CP/LCU children were characterised as cheeky and endearing, with parents reporting good rapport. Families with CP/HCU children presented with specific difficulties in affective involvement and parents described challenges which were in line with the child's specific presentation of lack of empathy and shallow affect. These findings may be used to help clinicians identify targets for family interventions.

Sleep and metabolism are essential components of health. Metabolic health depends largely on individual's lifestyle. Disturbances in sleep health, such as changes in sleep patterns that are associated with menopause/reproductive aging and chronologic aging, may have metabolic health consequences. Sleep restriction and age-related changes in sleep and circadian rhythms may influence changes in appetite and reproductive hormones, energy expenditure, and body adiposity. In this article, the authors describe how menopause-related sleep disturbance may affect eating behavior patterns, immunometabolism, immunometabolic dysfunction, and associations between sleep and metabolic outcomes.

BACKGROUND: Many women experience both vasomotor menopausal symptoms (VMS) and depressed mood at midlife, but little is known regarding the prospective bi-directional relationships between VMS and depressed mood and the role of sleep difficulties in both directions.

METHODS: A pooled analysis was conducted using data from 21 312 women (median: 50 years, interquartile range 49-51) in eight studies from the InterLACE consortium. The degree of VMS, sleep difficulties, and depressed mood was self-reported and categorised as never, rarely, sometimes, and often (if reporting frequency) or never, mild, moderate, and severe (if reporting severity). Multivariable logistic regression models were used to examine the bi-directional associations adjusted for within-study correlation.

RESULTS: At baseline, the prevalence of VMS (40%, range 13-62%) and depressed mood (26%, 8-41%) varied substantially across studies, and a strong dose-dependent association between VMS and likelihood of depressed mood was found. Over 3 years of follow-up, women with often/severe VMS at baseline were more likely to have subsequent depressed mood compared with those without VMS (odds ratios (OR) 1.56, 1.27-1.92). Women with often/severe depressed mood at baseline were also more likely to have subsequent VMS than those without depressed mood (OR 1.89, 1.47-2.44). With further adjustment for the degree of sleep difficulties at baseline, the OR of having a subsequent depressed mood associated with often/severe VMS was attenuated and no longer significant (OR 1.13, 0.90-1.40). Conversely, often/severe depressed mood remained significantly associated with subsequent VMS (OR 1.80, 1.38-2.34).

CONCLUSIONS: Difficulty in sleeping largely explained the relationship between VMS and subsequent depressed mood, but it had little impact on the relationship between depressed mood and subsequent VMS.