Daytime napping, sleep duration and increased 8-year risk of type 2 diabetes in a British population.

BACKGROUND AND AIMS: Few studies have prospectively examined the relationship between daytime napping and risk of type 2 diabetes. We aimed to study the effects of daytime napping and the joint effects of napping and sleep duration in predicting type 2 diabetes risk in a middle- to older-aged British population. METHODS AND RESULTS: In 1998-2000, 13 465 individuals with no known diabetes participating in the European Prospective Investigation into Cancer-Norfolk study reported daytime napping habit and 24-h sleep duration. Incident type 2 diabetes cases were identified through multiple data sources until 31 July 2006. After adjustment for age and sex, daytime napping was associated with a 58% higher diabetes risk. Further adjustment for education, marital status, smoking, alcohol intake, physical activity, comorbidities and hypnotic drug use had little influence on the association, but additional adjustment for BMI and Waist Circumference attenuated the Odds ratio (OR) (95% CI) to 1.30 (1.01, 1.69). The adjusted ORs (95% CI) associated with short and long sleep duration were 1.46 (1.10, 1.90) and 1.64 (1.16, 2.32), respectively. When sleep duration and daytime napping were examined together, the risk of developing diabetes more than doubled for those who took day naps and had less than 6 h of sleep, compared to those who did not nap and had 6-8 h of sleep. CONCLUSION: Daytime napping was associated with an increased risk of type 2 diabetes, particularly when combined with short sleep duration. Further physiological studies are needed to confirm the interaction between different domains of sleep in relation to diabetes risk.

The association between social stress and global cognitive function in a population-based study: the European Prospective Investigation into Cancer (EPIC)-Norfolk study.

BACKGROUND: Stress is thought to exert both positive and negative effects on cognition, but the precise cognitive effects of social stress and individuals' response to stress remain unclear. We aimed to investigate the association between different measures of social stress and cognitive function in a middle- to older-aged population using data from the European Prospective Investigation into Cancer (EPIC)-Norfolk study. METHOD: Participants completed a comprehensive assessment of lifetime social adversity between 1993 and 1997 and the short form of the Mini Mental State Examination (SF-MMSE), an assessment of global cognitive function, during the third health check between 2004 and 2011 (a median of 10.5 years later). A low MMSE score was defined as a score in the bottom quartile (20-26). RESULTS: Completed MMSE scores and stress measures were available for 5129 participants aged 48-90 years. Participants who reported that their lives had been more stressful over the previous 10 years were significantly more likely to have low MMSE scores [odds ratio (OR) 1.14, 95% confidence interval (CI) 1.04-1.24 per unit increase in perceived stress], independently of sociodemographic factors, physical and emotional health. The effects were restricted to the highest level of stress and the association was stronger among participants with a lower educational level. Adaptation following life event experiences also seemed to be associated with MMSE scores after adjusting for sociodemographic factors, but the association was attenuated with further adjustment. CONCLUSIONS: In this generally high-functioning population, individuals' interpretations and responses to stressful events, rather than the events themselves, were associated with cognitive function.

Association between serotonin 5-HT-2C receptor gene (HTR2C) polymorphisms and obesity- and mental health-related phenotypes in a large population-based cohort.

OBJECTIVE: Studies have shown that common single-nucleotide polymorphisms (SNPs) in the serotonin 5-HT-2C receptor (HTR2C) are associated with antipsychotic agent-induced weight gain and the development of behavioural and psychological symptoms. We aimed to analyse whether variation in the HTR2C is associated with obesity- and mental health-related phenotypes in a large population-based cohort. METHOD: Six tagSNPs, which capture all common genetic variation in the HTR2C gene, were genotyped in 4978 men and women from the European Prospective Investigation into Cancer (EPIC)-Norfolk study, an ongoing prospective population-based cohort study in the United Kingdom. To confirm borderline significant associations, the -759C/T SNP (rs3813929) was genotyped in the remaining 16 003 individuals from the EPIC-Norfolk study. We assessed social and psychological circumstances using the Health and Life Experiences Questionnaire. Genmod models were used to test associations between the SNPs and the outcomes. Logistic regression was performed to test for association of SNPs with obesity- and mental health- related phenotypes. RESULTS: Of the six HTR2C SNPs, only the T allele of the -759C/T SNP showed borderline significant associations with higher body mass index (BMI) (0.23 kg m(-2); (95% confidence interval (CI): 0.01-0.44); P=0.051) and increased risk of lifetime major depressive disorder (MDD) (Odds ratio (OR): 1.13 (95% CI: 1.01-1.22), P=0.02). The associations between the -759C/T and BMI and lifetime MDD were independent. As associations only achieved borderline significance, we aimed to validate our findings on the -759C/T SNP in the full EPIC-Norfolk cohort (n=20 981). Although the association with BMI remained borderline significant (beta=0.20 kg m(-2); 95% CI: 0.04-0.44, P=0.09), that with lifetime MDD (OR: 1.01; 95% CI: 0.94-1.09, P=0.73) was not replicated. CONCLUSIONS: Our findings suggest that common HTR2C gene variants are unlikely to have a major role in obesity- and mental health-related traits in the general population.

Prospective association between emotional health and clinical evidence of Parkinson's disease.

BACKGROUND AND PURPOSE: Whilst disorders of emotion are commonly comorbid with Parkinson's disease (PD), evidence concerning their association with PD risk is limited. We investigate the prospective association between selected measures of emotional health and incident suspected PD. METHODS: 20,855 men and women, considered PD-free at baseline, completed a postal assessment of major depressive disorder (MDD), generalized anxiety disorder (GAD), psychological distress [defined by the five-item Mental Health Inventory (MHI-5)], and neuroticism. PD case ascertainment was based upon PD medication use, self-report questionnaires, hospital record discharge codes, and death certification, subsequently checked against general practitioner, hospital records and neurological service records. RESULTS: 175 suspected cases of incident PD were identified in 160,725 (median 7.9) person-years of follow-up (with 43 recorded in neurological service records). MDD lifetime history, GAD lifetime history, MHI-5 and neuroticism were all significantly associated with suspected PD following adjustment for age, sex, cigarette smoking, alcohol consumption, social class and education. CONCLUSIONS: This study supports an association between measures of emotional health, assessed prior to evidence of motor symptoms, and subsequent suspected PD diagnosis. However, we were unable to determine whether our measures of personality and emotional health represent genuine premorbid risk factors or early stages of PD. Long-term prospective healthy cohort studies are required to investigate the relationship between emotional health history and the evolution of the premotor and motor phases of PD.

Lifestyle risk factors for cancer: the relationship with psychosocial work environment.

BACKGROUND: Psychosocial work characteristics (job demands, control, support, job strain and iso-strain [high job strain combined with social isolation at work]) may be linked to cancer risk, by affecting cancer-related lifestyles like smoking, high alcohol consumption, low intake of fruits and vegetables and lack of physical activity. METHODS: Cross-sectional data obtained from 3309 respondents participating in an ongoing prospective cohort study in the Netherlands on psychosocial factors and cancer risk were used to study the association between psychosocial job characteristics and lifestyle. Information on job characteristics and risk factor prevalence was collected from 20-65-year-old men and women, through self-administered questionnaires. Multiple logistic and linear regression analyses were undertaken by gender, with adjustment for age and education. RESULTS: No differences in the prevalence of lifestyle risk factors for cancer were found amongst the psychosocial work characteristics studied. Moreover, little evidence was found for a relation between job (or iso-) strain and cancer-related lifestyles in multivariate analyses. CONCLUSIONS: The present study found no support for the hypothesis that job strain or iso-strain are associated with a cancer-related lifestyle. Further research on the role of other psychosocial factors-like personality or social support outside work-in mediating associations between job characteristics and lifestyle, is warranted.

Places, people, and their physical and mental functional health.

STUDY OBJECTIVE: To investigate the impact of area of residence on functional health as represented by medical outcomes study SF-36 physical and mental component summary scores. DESIGN: Multilevel analysis of cross sectional data from the European Prospective Investigation into Cancer and Nutrition in Norfolk, UK (EPIC-Norfolk). PARTICIPANTS: A community dwelling cohort of 18399 men and women, aged 41 to 80 and resident in 162 electoral wards in Norfolk, UK. MAIN RESULTS: Significant residual variation in physical functional health was observed at the area level after controlling for important individual level socioeconomic factors (p<0.001). However, the extent of this variation was modest when compared with that at the individual level (representing 0.6% of the total). About half of this variation could be explained by area deprivation. Area deprivation was associated with impaired mental functional health but residual variation at the area level (adjusted for individual level factors) was observed only for men (0.5% of total, p = 0.02). CONCLUSIONS: Area of residence was associated with physical functional health, albeit with modest effect size. Evidence for an association between area of residence and mental functional health was weak.

Psychosocial aetiology of chronic disease: a pragmatic approach to the assessment of lifetime affective morbidity in an EPIC component study.

OBJECTIVES: The Health and Life Experiences Questionnaire (HLEQ) was developed for use in a prospective cohort study of 25,000 men and women living in Norfolk and forms a component study of the European Prospective Investigation into Cancer and Nutrition (EPIC). The HLEQ includes an assessment of mood status over the life course allowing a limited capacity for the imposition of diagnostic criteria to enable eventual evaluation of mental health status for chronic disease outcomes. This paper reports estimates of HLEQ Major Depressive Disorder (MDD) prevalence and compares them with those obtained through interviewer-based methods. In addition evidence for the impact of recall, clustering or cohort effects on these estimates are examined. PARTICIPANTS: 3491 eligible respondents to EPIC in Norfolk, aged 45-74 years, recruited from the first five general practices who completed the HLEQ. MAIN RESULTS: MDD prevalence estimates were found to be closely comparable to those obtained recently (by interview) in the UK and to those lifetime MDD rates determined through international studies. Risk of MDD onset was found to vary with age as expected from earlier studies using interviewer-based assessments. Limited evidence was found to show that the distribution of first onset MDD episodes were compressed during the immediate pre-assessment period. Results were also consistent with previous evidence demonstrating the raised risk of MDD among women and of the decline in gender differences with advancing age. CONCLUSIONS: These results suggest that estimates of putative MDD diagnostic status, derived through the HLEQ, and of associated demographic risk are similar to those derived by more intensive and costly assessment methods. Implications for the future study of MDD both as an outcome and as a risk factor for chronic disease are discussed.

Binary and rate measures of life event experience: their association with illness onset in Edinburgh and London community surveys.

This report examines the extent to which a binary stress index (the experience of at least one severe event) and event rate measures were successful in predicting onset of psychiatric disorder amongst 1029 women. Analyses were based upon samples drawn from Edinburgh and London communities. Whilst the binary measures were successful in discriminating cases from non-cases within each sample, they were less powerful than measures based upon the rate at which events (usually severe) had been experienced. The results are discussed in terms of their relevance to issues of the health consequences of experiencing multiple events, and of the duration over which stressful events may have an influence on psychiatric health.

Psychiatric morbidity in two matched community samples: a comparison of rates and risks in Edinburgh and St. Louis.

The use of different diagnostic classifications of psychiatric disorder in the United States and the United Kingdom, together with associated changes in the operational definitions of disorder, has placed additional barriers in the way of U.S./U.K. comparative studies. However, the parallel development of two general population studies, one in Edinburgh and one in St. Louis, MO, has enabled a comparative analysis with limited objectives, to be undertaken. This paper presents results based upon matched samples of women from these studies. The findings revealed current overall prevalence, and the socio-demographic determinants of prevalence, to be similar in the two city samples. The results additionally indicate the consequence of applying diagnostic criteria appropriate to different ranges of psychiatric syndromes for the estimation of prevalence in general population samples.

Childhood adversity, gender and depression over the life-course.

BACKGROUND: Full investigation of hypotheses concerning early risk factors and episodes of depression in adult life requires consideration of the separate risks of first onset and of recurrent episodes. This paper is based upon such an investigation. METHODS: A sample of participants in a large-scale population study (n=3491) provided information through retrospective assessment of lifetime history of (putative) major depressive disorder and of their adverse experiences in childhood. A statistical model based on Poisson regression, that combined both the (survival) distribution of first onset times with the subsequent rate of episode recurrence was specified to permit investigation of the gender difference in lifetime depression and the influence of childhood adversities on adult depression. RESULTS: A gender difference (with women at increased risk) was revealed for first onsets of depression only and was found to decrease with increasing age, being no longer apparent in those aged over 50. Experience either of a frightening event or of physical abuse in childhood was associated with an increased risk of first onset in younger adults (those aged < or =30). LIMITATIONS: The method of data collection used in this study warrants some caution in the interpretation of substantive findings. CONCLUSIONS: The relationships revealed concerning the risk for early and for late first onset and the risk of recurrence suggest different causal pathways underlying the associations between risk factors experienced early in life and depression in adulthood. Analyses that take full account of episode history can aid understanding of the origins of depression in adulthood.

Life events and other factors implicated in onset and in remission of psychiatric illness in women.

Life stressors for 574 Edinburgh women were assessed for uncertain outcome, impaired relationships and other characteristics. Thirteen weeks were covered either with no illness present or before a transient episode of Research Diagnostic Criteria (RDC)-defined anxiety/depression (duration less than 13 weeks) or before a longer episode or before illness remission or during continuing illness. Exploratory analysis suggested that stressors of uncertain outcome preceded longer illness onset. Impaired relationships went with continuing illness. Stressors with neither of these, and with fewer than two other characteristics, preceded transient illness. Remaining stressors predicted remission, as did ending of long-term difficulties. Self-esteem, support, coping, previous illness and marital status also discriminated between the groups.

Life events and the onset of affective disorder. A longitudinal general population study.

This paper examines the relationship between life events (ascertained by the Bedford College method) and the onset of affective disorder (defined according to the RDC scheme) in a longitudinal general population survey of women. Fall-off in the reporting of minor events is examined and discussed. Event rates, proportions of women challenged by events, and measures of the risk of RDC disorder associated with the experience of particular events are reported. The results based upon data from an initial interview were largely consistent with those based upon follow-up data, and underpinned earlier work. For both data sets, major difficulties were associated with illness onset. Severe dependent events showed stronger effects than severe independent events but both categories were rare. New substantive findings arising from short-term general population event research are unlikely.

Do psychological factors predict survival in breast cancer?

One hundred and twenty-two women with primary operable breast cancer were interviewed before and three months after mastectomy. The outcome of 121 of the women was assessed 6-8 years after operation. Women who were regarded as having enough symptoms to fulfil the criteria for a psychiatric illness (according to Research Diagnostic Criteria (RDC) and the General Health Questionnaire (GHQ) before operation were less likely to have a recurrence during the follow-up. Those who were assessed three months after operation as coping by using a strategy of denial had a better chance of remaining recurrence-free than those women employing other coping strategies; this finding must be viewed with reservation because of the inherent difficulties in measuring coping strategies. These psychological measures improved the prediction of recurrence-free survival beyond that achieved by other variables (e.g. histological node status, tumour size and treatment).

The electrodermal component of the orienting response in blind and deaf individuals.

Skin conductance response (SCR) was monitored as an index of the orienting response (OR) to a series of 20 tones presented to blind and sighted schoolchildren. Blind children showed fewer criterion SCRs than sighted children, and significantly more of the blind sample exhibited SCR habituation. The blind group also demonstrated fewer non-specific SCRs than sighted control subjects, but demonstrated a higher average skin conductance level (SCL). A second experiment found similar effects for deaf versus hearing children presented with simple visual stimulation, save that no significant difference was observed between these groups in SCL. These results can be explained by assuming that loss of modality results in more efficient development of a neuronal model of the salient features of stimuli impinging on the remaining intact modalities. An explanation in terms of the assessed significance of the stimulus situation can also be entertained. The atypical skin conductance activity of three of the blind group was given separate consideration.

Characteristics of patients and patterns of psychiatric service use in ethnic minorities.

BACKGROUND: The differential uptake of psychiatric services by ethnic minorities has been widely reported. Less attention has been given to comparisons of these patients and variations in the types of interventions they receive. AIMS: To assess whether for people accessing psychiatric services in the UK, differences exist across ethnic groups both in their sociodemographic characteristics and patterns of mental health care utilisation. METHODS: All adults resident in an inner city health district and using psychiatric services during a six-month period were identified. Demographic, clinical and service use data were collected from staff and records. These were compared across black Caribbean, Indian, Pakistani, Irish and white ethnic groups for two broad diagnostic categories: psychotic/bipolar and depressive/neurotic disorders. RESULTS: There were significant differences between ethnic groups on most demographic variables in each of the diagnostic categories. There were variations in the level of contact with different mental health professionals. The only significant difference in the use of specific services was for those with psychotic/bipolar disorders, black Caribbean patients being more likely to be detained in hospital compulsorily. CONCLUSIONS: Ethnic diversity both in the characteristics of patients and their patterns of psychiatric care should be addressed when planning and developing services.

Psychological distress, major depressive disorder, and risk of stroke.

BACKGROUND: Studies have suggested that mood status is associated with an increased risk of stroke, though mostly based on measures of depression defined by symptoms alone rather than diagnostic criteria representative of clinically important distress and impairment. We investigated this association based upon a large population-based prospective cohort study. METHODS: Baseline assessment of major depressive disorder (MDD) and of mental health well-being (defined by the Mental Health Inventory, MHI-5) was completed by 20,627 stroke-free participants, aged 41 to 80 years, in the United Kingdom European Prospective Investigation into Cancer-Norfolk study. RESULTS: During 8.5 years of follow-up, 595 incident (fatal and nonfatal) stroke endpoints were recorded. Neither past year nor lifetime MDD was associated with stroke. A one SD decrease in MHI-5 scale score (representing greater emotional distress) was associated with an 11% increased risk of stroke after adjustment for age, sex, cigarette smoking, systolic blood pressure, cholesterol, obesity, preexisting myocardial infarction, diabetes, social class, education, hypertension treatment, family history of stroke, and antidepressant medication use (hazard ratio 1.11, 95% CI 1.00 to 1.22). This association was consistent for men and for women, for fatal and nonfatal stroke, and conformed to a dose-response relationship. CONCLUSIONS: Findings from this large prospective cohort study suggest that increased psychological distress is associated with elevated stroke risk. Episodic major depressive disorder was not associated with incident stroke in this study.

Sense of coherence, lifestyle choices and mortality.

BACKGROUND: Based on data from the European Prospective Investigation into Cancer, Norfolk (EPIC-Norfolk) study, we have previously shown a strong sense of coherence (SOC) to be associated with a reduced rate of all-cause mortality. OBJECTIVES: To investigate the extent to which the SOC mortality association can be explained by socioeconomic status and lifestyle choices. DESIGN AND SETTING: Prospective population-based cohort study. PARTICIPANTS: 18 287 study participants aged 41-80 years who reported no pre-existing chronic disease at baseline and who completed an assessment of SOC. RESULTS: Based on 1599 deaths during a mean follow-up of 8.3 years, a strong SOC was associated with a 20% reduced risk of all-cause mortality. Measures of lifestyle choice (cigarette smoking, physical activity, dietary intakes of fruit, vegetables and fibre) and socioeconomic status (social class and education) explained 23% of this association. CONCLUSIONS: The SOC concept embraces multiple sets of chronic disease risk factors that include lifestyle choices and those associated with socioeconomic status, and is a potential aid in understanding differences in health outcomes in similar individuals.

Psychosocial factors and incident asthma hospital admissions in the EPIC-Norfolk cohort study.

BACKGROUND: Case series and case-control studies have shown high rates of psychosocial and behavioural risk factors amongst patients admitted to hospital with severe asthma. General population studies have shown associations between psychosocial factors and prevalent asthma but few have investigated incident asthma outcomes. METHODS: Data on psychosocial factors and asthma hospital admissions were available for 20 854 participants, aged 41-80 years, in the Norfolk cohort of the European Prospective Investigation into Cancer study. Postal assessments included details of physical functioning, mood disorder history, social adversity and social support. RESULTS: A total of 686 asthma hospital admissions were recorded. Psychosocial factors present at baseline, including current mood disorders, adverse circumstances in childhood, the impact of life events experienced during adulthood and negative perceived support from a close confidant, were associated with increased rates of hospital admission independent of age, sex, indicators of socio-economic status, physical functional health, and obesity. Restricted to those participants who reported lifetime doctor-diagnosed asthma at baseline, the reported impact of adverse life events experienced in adulthood, and both confiding and negative aspects of support quality, were associated with asthma hospital admission. The magnitude of these associations was comparable to those involving indicators of socio-economic status and physical health. CONCLUSIONS: These results show that psychosocial factors are associated with incident asthma hospital admissions and highlight the potential importance of taking account of psychosocial factors, including availability and quality of support networks, in guiding long-term asthma management.

Physical health-related quality of life predicts stroke in the EPIC-Norfolk.

OBJECTIVE: To examine the relationship between Short Form (SF)-36 physical functional health-related quality of life and incident stroke. METHODS: A total of 13,615 men and women participating in the European Prospective Investigation into Cancer-Norfolk who were free of stroke, myocardial infarction, and cancer at baseline were included in the study. Participants completed a health and lifestyle questionnaire and attended a health examination during 1993 to 1997. Self-reported physical functional health was assessed using physical component summary scores of SF-36 18 months later. Stroke incidence was ascertained by death certification and hospital record linkage up to 2005. RESULTS: There were 244 incident strokes (total person years = 99,191). People who reported better physical functional health had significantly lower risk of incident stroke. Using Cox proportional hazard models adjusting for age, sex, body mass index, systolic blood pressure, cholesterol, smoking, diabetes, physical activity, social class, alcohol consumption, and respiratory function, men and women who were in the top quartile of SF-36 physical component summary scores had half the risk of stroke (RR = 0.50 [0.31, 0.78]) compared to the people in the bottom quartile. The relationships remained unchanged after excluding strokes occurring within the first 2 years of follow-up. CONCLUSIONS: Physical functional health-related quality of life measured as Short Form-36 predicts subsequent stroke risk independently of known risk factors in a general population. Poor physical functional health may indicate a high-risk population for stroke who may benefit most from targeted preventive interventions such as management of known risk factors.

Respiratory function and self-reported functional health: EPIC-Norfolk population study.

Respiratory function is known to be associated with mortality. However, its association with health related quality of life (HRQoL) has not yet been examined. A population-based cross sectional study was conducted in 16,738 subjects aged 40-79 yrs and resident in Norfolk, to examine the association between forced expiratory volume in one second (FEV1) and HRQoL measured by the 36-item short form questionnaire. Individuals who were in the highest quintiles of FEV1 were more likely to report good physical functional health (odds ratio (OR) 1.60; 95% confidence interval (CI) 1.28-2.01 and OR 1.71; 95% CI 1.40-2.10 for males and females, respectively) controlling for age, height, weight or body mass index, smoking, physical activity, prevalent illness and social class. Being in the highest quintile for FEV1 was associated with significantly lower likelihood of poor self-reported mental functional health status in males (OR 0.78; 95% CI 0.61-0.99), but not in females (OR 1.00; 95% CI 0.82-1.22). In conclusion, forced expiratory volume in one second independently predicts self perceived physical well being in a general population across the whole normal distribution of respiratory function.