Marta Jackowska

Psychosocial Factors and Sleep Efficiency: Discrepancies Between Subjective and Objective Evaluations of Sleep

Objectives: Self-reported sleep efficiency may not precisely reflect objective sleep patterns. We assessed whether psychosocial factors and affective responses are associated with discrepancies between subjective reports and objective measures of sleep efficiency. Methods: Participants were 199 working women aged 20 to 61 years. Standardized questionnaires were used to assess psychosocial characteristics and affect that included work stress, social support, happiness, and depressive symptoms. Objective measures of sleep were assessed on one week and one leisure night with an Actiheart monitor. Self-reported sleep efficiency was derived from the Jenkins Sleep Problems Scale. Discrepancies between self-reported and objective measures of sleep efficiency were computed by contrasting standardized measures of sleep problems with objectively measured sleep efficiency. Results: Participants varied markedly in the discrepancies between self-reported and objective sleep measures. After adjustment for personal income, age, having children, marital status, body mass index, and negative affect, overcommitment (p = .002), low level of social support (p = .049), and poor self-rated heath (p = .02) were associated with overreporting of sleep difficulties and underestimation of sleep efficiency. Self-reported poor sleep efficiency was more prevalent among those more overcommitted at work (p = .009) and less happy (p = .02), as well as among those with lower level of social support (p = .03) and more depressive symptoms (p = .048), independently of covariates. Objective sleep efficiency was unrelated to psychosocial characteristics or affect. Conclusions: The extent to which self-reported evaluations of sleep efficiency reflect objective experience may be influenced by psychosocial characteristics and affect. Unless potential moderators of self-reported sleep efficiency are taken into account, associations between sleep and psychosocial factors relevant to health may be overestimated.BMI = body mass index; CVD = cardiovascular disease; PSG = polysomnography

Exploring age differences in reasons for nonattendance for cervical screening: a qualitative study

Please cite this paper as: Waller J, Jackowska M, Marlow L, Wardle J. Exploring age differences in reasons for nonattendance for cervical screening: a qualitative study. BJOG 2012;119:26–32.

Short sleep duration is associated with shorter telomere length in healthy men: findings from the Whitehall II cohort study.

Background Shorter telomere length and poor sleep are more prevalent at older ages, but their relationship is uncertain. This study explored associations between sleep duration and telomere length in a sample of healthy middle and early old age people. Methods Participants were 434 men and women aged 63.3 years on average drawn from the Whitehall II cohort study. Sleep duration was measured by self-report. Results There was a linear association between sleep duration and leukocyte telomere length in men but not in women (P = 0.035). Men reporting shorter sleep duration had shorter telomeres, independently of age, body mass index, smoking, educational attainment, current employment, cynical hostility scores and depressive symptoms. Telomeres were on average 6% shorter in men sleeping 5 hours or fewer compared with those sleeping more than 7 hours per night. Conclusion This study adds to the growing literature relating sleep duration with biomarkers of aging, and suggests that shortening of telomeres might reflect mechanisms through which short sleep contributes to pathological conditions in older men.

Sleep and biomarkers in the English Longitudinal Study of Ageing: Associations with C-reactive protein, fibrinogen, dehydroepiandrosterone sulfate and hemoglobin

Sleep duration and quality are associated with adverse physical health outcomes. The mechanisms are not well understood, and little is known about associations with biomarkers in older population cohorts. This study assessed cross-sectional associations between self-reported sleep measures and biomarkers in a representative sample of British people aged 50 years and above. Participants were 6465 men and women aged 50-99 years from the English Longitudinal Study of Ageing (ELSA). Associations of sleep duration and sleep disturbance with C-reactive protein (CRP), fibrinogen, dehydroepiandrosterone sulfate (DHEAS) and hemoglobin were analyzed, adjusting for age, wealth, body mass index (BMI), smoking, physical activity, limiting long-standing illness and depressive symptoms. In men, long sleep duration (OR: 1.50, 1.05-2.14) and greater sleep disturbance (OR: 1.29, C.I. 1.05-1.59) were associated with raised CRP levels, while long sleep was also related to raised plasma fibrinogen (P=0.001). DHEAS levels were lower among men reporting more sleep disturbances (P=0.016), but were not related to sleep duration. Sleep duration (P=0.015) and sleep disturbance (P=0.039) were associated with lower hemoglobin levels, and anemia was more prevalent among men with disturbed sleep (OR: 1.73, C.I. 1.13-2.65). In women more disturbed sleep was associated with greater likelihood of anemia (OR: 1.59, C.I. 1.02-2.46), but there was no relationship between sleep disturbance or duration with other biomarkers. This study suggests that self-reported sleep duration and disturbance are related to biological risk factors in community-dwelling older adults, with different associations being present in men and women. A better understanding of these relationships using longitudinal cohort studies will broaden our understanding of the mechanisms relating sleep indices and ill health in advancing age.

Sleep and future cardiovascular risk: prospective analysis from the English Longitudinal Study of Ageing

STUDY OBJECTIVES Hypertension and inflammation may contribute to the increased risk of cardiovascular disease in individuals with suboptimal sleep, but large prospective studies are lacking. This study tested whether sleep duration and disturbance were predictive of incident hypertension and inflammation four years later. METHODS Participants were men and women aged 50 years and older from the English Longitudinal Study of Ageing. Sleep was assessed by self-report, incident hypertension (N = 3068) was defined by clinical examination and C-reactive protein and fibrinogen (N = 3768) were measures of inflammation. RESULTS Both men (odds ratio, OR:1.73, confidence interval, C.I. 1.08-2.76) and women (OR: 1.44, C.I. 1.00-2.07) reporting short sleep at baseline had increased odds of incident hypertension 4 years later, after adjustment for covariates. Age-stratified analyses revealed that short sleep was predictive of incident hypertension in men (OR: 2.27, C.I. 1.01-5.11) and women (OR: 2.10, C.I. 1.08-4.09) younger than 60 years but not in older people. Disturbed sleep also predicted incident hypertension in men (OR: 1.20, C.I. 1.02-1.41). In women, disturbed sleep was associated with elevated C-reactive protein (B = 0.030, C.I. 0.00-0.06) and fibrinogen (B = 0.030, C.I. 0.01-0.05) at follow-up controlling for baseline inflammation and other covariates. Sleep duration was unrelated to inflammatory markers in either sex. CONCLUSIONS This study of older men and women adds to growing evidence that aberrant sleep patterns may increase the risk of cardiovascular outcomes through its adverse impact on blood pressure and inflammation.

The impact of a brief gratitude intervention on subjective well-being, biology and sleep.

This randomised controlled experiment tested whether a brief subjective well-being intervention would have favourable effects on cardiovascular and neuroendocrine function and on sleep. We compared 2 weeks of a gratitude intervention with an active control (everyday events reporting) and no treatment conditions in 119 young women. The treatment elicited increases in hedonic well-being, optimism and sleep quality along with decreases in diastolic blood pressure. Improvements in subjective well-being were correlated with increased sleep quality and reductions in blood pressure, but there were no relationships with cortisol. This brief intervention suggests that subjective well-being may contribute towards lower morbidity and mortality through healthier biological function and restorative health behaviours.

Sleep problems and heart rate variability over the working day

The purpose of this study was to discover whether greater sleep problems are associated with reduced heart rate variability during working hours and at night, and to determine whether this association is in part mediated by experienced affective states. This study involved 199 working women with a mean age of 33.8 years. Sleep problems were assessed with the Jenkins Sleep Problems Scale, and the Day Reconstruction Method was used to measure positive affect and stress on the evening before and during the working day. Heart rate variability was indexed by the mean square root of the successive standard difference in heart period. Disturbed sleep was inversely related to heart rate variability during the working day (P = 0.022), independently of demographic and behavioural confounders. Additional adjustment for positive affect and stress did not lead to further reductions in the association between sleep problems and reduced heart rate variability over the work day. Sleep problems were not predictive of reduced night‐time heart rate variability. This report extends the findings from experimental studies and clinical samples, and suggests that disturbed sleep might impair heart rate variability in real life settings, in particular during working hours. Reduced heart rate variability might be a potential pathway linking sleep problems with cardiovascular disease. Based on the current data there was little evidence that the inverse associations between sleep problems and heart rate variability were mediated by experienced affective states.

Cervical screening among migrant women: a qualitative study of Polish, Slovak and Romanian women in London, UK

Objective To explore awareness of and participation in cervical screening services in women from Poland, Slovakia and Romania living in London, UK. Methods Three qualitative studies were carried out in London in 2008–2009: an interview study of professionals working with Central and Eastern European migrants (n=11); a focus group study including three Polish, one Slovak and one Romanian focus group; and an interview study of Polish (n=11), Slovak (n=7) and Romanian (n=2) women. Results Awareness of the cervical screening programme was good, but understanding of the purpose of screening was sometimes limited. Some women were fully engaged with the UK screening programme; others used screening both in the UK and their countries of origin; and a third group only had screening in their home countries. Women welcomed the fact that screening is free and that reminders are sent, but some were concerned about the screening interval and the age of the first invitation. Conclusions Migrant women from Poland, Slovakia and Romania living in London vary in their level of participation in the National Health Service Cervical Screening Programme. More needs to be done to address concerns regarding screening services, and to ensure that language is not a barrier to participation.

Biological and psychological correlates of self-reported and objective sleep measures

OBJECTIVE Objective and self-reported sleep are only moderately correlated and it is uncertain if these two types of sleep measures are associated with distinct biological and psychological outcomes. METHODS Participants were 119 healthy women aged 26years on average. Cortisol and blood pressure assessed over one day were the measures of biological function. Psychological variables included optimism, life satisfaction, positive and negative affect as well as emotional distress. Sleep was assessed with the Pittsburgh Quality Index (PSQI), wrist actigraphy and sleep diaries. RESULTS Global sleep ratings on the PSQI were unrelated to objective sleep efficiency, duration or latency. Sleep duration derived from sleep diaries was highly correlated with objective duration but was unrelated to the PSQI measure. More disturbed sleep on the PSQI was associated with lower psychological wellbeing, as indicated by reduced levels of optimism, life satisfaction and positive affect as well as greater negative affect and emotional distress. Objective sleep efficiency was reduced among participants with lower positive and higher negative affect but there were no other associations between objective sleep indicators and psychological variables tested in our study. Participants with poorer self-reported sleep had lower cortisol awakening response while those with longer objective sleep latency had higher diastolic blood pressure, independently of covariates. CONCLUSION Our study reveals that self-reported and objective sleep measures, in particular those regarding sleep quality, are weakly associated but have different psychological and biological correlates. This suggests that findings relating self-reported sleep may not necessarily be corroborated by objective sleep indicators.