Cumulative social risk exposure in childhood and smoking and excessive alcohol use in adulthood.

BACKGROUND: Social inequalities in adult smoking and excessive alcohol intake may be associated with exposure to multiple childhood social risk factors across different domains of risk within the household. METHODS: We used data from a cross-sectional cohort study of adults (40-75 years) in 1993-97 living in England (N = 19466) to examine the association between clusters of childhood social risks across different domains with adult smoking and excessive alcohol use. Participants reported exposure to six childhood social risk factors, current smoking behaviour and alcohol intake. Factor analysis was used to identify domains of social risk. We created a childhood cumulative domain social risk score (range 0-2) from summing the total number of domains. RESULTS: Factor analysis identified two domains of childhood social risk within the household: maladaptive family functioning (parental unemployment, substance misuse, physical abuse) and parental separation experiences : maternal separation, divorce, being sent away from home). Compared to those children with risk exposure in no single domain, children with risk exposure in both domains (i.e. maladaptive family functioning, parental separation experiences) had a higher prevalence of adult smoking [men: Prevalence ratio (PR) = 1.74, 95% confidence intervals (CI): 1.35-2.26; women: PR = 1.71 95% CI: 1.34-2.18]. There was a trend association between the number of childhood social risk domains and adult smoking (both sexes: P < 0.001) and excessive alcohol use (men: P <0.008). CONCLUSIONS: Further work is needed to understand if addressing cumulative risk exposure to maladaptive family functioning and parental separation experiences can reduce social inequalities in adult smoking and excessive alcohol intake.

Daytime napping and the risk of all-cause and cause-specific mortality: a 13-year follow-up of a British population.

Epidemiologic studies have reported conflicting results on the relationship between daytime napping and mortality risk, and there are few data on the potential association in the British population. We investigated the associations between daytime napping and all-cause or cause-specific mortality in the European Prospective Investigation Into Cancer-Norfolk study, a British population-based cohort study. Among the 16,374 men and women who answered questions on napping habits between 1998 and 2000, a total of 3,251 died during the 13-year follow-up. Daytime napping was associated with an increased risk of all-cause mortality (for napping less than 1 hour per day on average, hazard ratio = 1.14, 95% confidence interval: 1.02, 1.27; for napping 1 hour or longer per day on average, hazard ratio = 1.32, 95% confidence interval: 1.04, 1.68), independent of age, sex, social class, educational level, marital status, employment status, body mass index, physical activity level, smoking status, alcohol intake, depression, self-reported general health, use of hypnotic drugs or other medications, time spent in bed at night, and presence of preexisting health conditions. This association was more pronounced for death from respiratory diseases (for napping less than 1 hour, hazard ratio = 1.40, 95% confidence interval: 0.95, 2.05; for napping 1 hour or more, hazard ratio = 2.56, 95% confidence interval: 1.34, 4.86) and in individuals 65 years of age or younger. Excessive daytime napping might be a useful marker of underlying health risk, particularly of respiratory problems, especially among those 65 years of age or younger. Further research is required to clarify the nature of the observed association.

Social adversity experience and blood pressure control following antihypertensive medication use in a community sample of older adults.

BACKGROUND: Psychosocial stress is a risk factor for hypertension and has been shown to affect response to treatment for psychiatric illnesses. PURPOSE: We investigate the relationship between a history of social adversity experience and blood pressure control following antihypertensive medication use. METHODS: A total of 1,186 participants selected from the European Prospective Investigation into Cancer-Norfolk study (531 men and 655 women, aged 42 to 80 years) had attended two health checks at which blood pressure measurements were taken; were taking antihypertensive medication at the second, but not the first health check; and had completed a questionnaire assessment of their social and psychological circumstances which included details of traumatic experiences in childhood and of adverse life events, long-term difficulties, and perceived stress in adulthood. RESULTS: Experience of recent loss events in adulthood was associated with a smaller reduction in systolic blood pressure after starting hypertension treatment (ß = 1.78, 95 % confidence interval 0.15-3.40, per life event), independently of age, sex, preexisting health conditions, cigarette smoking history, alcohol consumption, physical activity, and obesity. CONCLUSION: Results from this study suggest that stress caused by recent losses may be associated with reduced effectiveness of treatment for hypertension. Subject to replication, these findings may help determine the specific physiological mechanisms by which medication treatment effectiveness is affected by stress.

Educational attainment and mean leukocyte telomere length in women in the European Prospective Investigation into Cancer (EPIC)-Norfolk population study.

BACKGROUND: Telomere length has been postulated as a marker of biological aging. Recent evidence has suggested that educational attainment but not social class is associated with telemore length. METHODS: We investigated the associations between educational attainment, social class and relative mean telomere length in an ethnically homogeneous population of 4441 women, aged 41-80 years. Mean telomere length was measured using high-throughput quantitative Real Time PCR. RESULTS: Educational attainment (p=0.015) but not social class (p=0.61) was associated with mean telomere length in these data. This association was independent of social class and of systolic blood pressure, high-density lipoprotein cholesterol, cigarette smoking, body mass index, glycated hemoglobin, plasma vitamin C and physical activity (p=0.014), and was not attenuated through additional adjustment for measures of social adversity, including those experienced during childhood (p=0.006). CONCLUSIONS: Our results, at least for women, provide support for the findings previously reported in this journal that lower educational attainment, but not social class, is associated with shorter telomere length.

Lifestyle behaviours and quality-adjusted life years in middle and older age.

OBJECTIVE: to examine the relationship between combined lifestyle behaviours and quality-adjusted life years (QALYs) in a general population. METHODS: a population-based study was conducted in 13,358 men and women who participated in the European Prospective Investigation into Cancer (EPIC)-Norfolk (baseline 1993-97). A score of 1 was given to each of non-smoking, physically not inactive, moderate alcohol consumption (1-14 units) and consumption of at least five portions of fruit and vegetables (vitamin C level ≥50 µmol/l). Short-Form Six-Dimension (SF-6D) health utility index scores were derived from the SF-36. QALYs were estimated up to follow-up (July 2007). RESULTS: a total of 13,358 men and women were eligible to be included in the study (aged 40-79 years at baseline). A total of 12,921 people were alive at follow-up (117, 784 person-years). Mean follow-up period was ∼11.5 years. 437 (4.4% of men and 2.4% of women) died. The death rate was 6.5 times higher in people with health behaviour score 0 compared with those who scored 4 (8.4 versus 1.3%). People with higher scores had significantly higher QALYs. CONCLUSION: our findings support the view that modifiable lifestyle factors are an important component in health improvement.

No evidence that social stress is associated with breast cancer incidence.

Women commonly attribute the experience of stress as a contributory cause of breast cancer. The purpose of this study is to investigate the associations between a history of social stress and breast cancer risk. A total of 11,467 women with no prior history of breast cancer, participants in the European Prospective Investigation into Cancer (EPIC)-Norfolk population-based prospective cohort study, completed a comprehensive assessment of lifetime social adversity exposure. Summary measures of social adversity were defined according to difficult circumstances in childhood, stressful life events and longer-term difficulties in adulthood, derived measures representing the subjective 'impact' of life events and associated 'stress adaptive capacity', and perceived stress over a 10-year period. Incident breast cancers were identified through linkage with cancer registry data. During 102,514 (median 9) person-years of follow-up, 313 incident breast cancers were identified. No associations were observed between any of the summary social adversity measures and subsequent breast cancer risk, with or without adjustment for age, menopausal status, parity, use of menopausal hormones, age at menarche, age at first birth, family history of breast cancer, physical activity, social class, body mass index, height, and alcohol intake. This study found no evidence that social stress exposure or individual differences in its experience are associated with the development of breast cancer. These findings may aid strategies designed to meet the psychosocial and emotional needs of breast cancer survivors and may be interpreted in a positive way in the context of commonly voiced beliefs that the experience of stress is a contributory cause of their disease.

Depression and ischemic heart disease mortality: evidence from the EPIC-Norfolk United Kingdom prospective cohort study.

OBJECTIVE: The authors investigated the association between major depressive disorder, including its clinical course, and mortality from ischemic heart disease. METHOD: This was a prospective cohort study of 8,261 men and 11,388 women 41-80 years of age who were free of clinical manifestations of heart disease and participated in the Norfolk, U.K., cohort of the European Prospective Investigation Into Cancer. The authors conducted a cross-sectional assessment of major depressive disorder during the period 1996-2000 and ascertained subsequent deaths from ischemic heart disease through linkage with data from the U.K. Office for National Statistics. RESULTS: As of July 31, 2006, 274 deaths from ischemic heart disease were recorded over a total follow-up of 162,974 person-years (the median follow-up period was 8.5 years). Participants who had major depression during the year preceding baseline assessment were 2.7 times more likely to die from ischemic heart disease over the follow-up period than those who did not, independently of age, sex, smoking, systolic blood pressure, cholesterol, physical activity, body mass index, diabetes, social class, heavy alcohol use, and antidepressant medication use. This association remained after exclusion of the first 6 years of follow-up data. Consideration of measures of major depression history (including recency of onset, recurrence, chronicity, and age at first onset) revealed recency of onset to be associated most strongly with ischemic heart disease mortality. CONCLUSIONS: Major depression was associated with an increased risk of ischemic heart disease mortality. The association was independent of established risk factors for ischemic heart disease and remained undiminished several years after the original assessment.

Major depression, C-reactive protein, and incident ischemic heart disease in healthy men and women.

OBJECTIVE: To investigate how C-reactive protein (CRP) and major depressive disorder (MDD) relate to each other and to incident ischemic heart disease (IHD). Studies have shown that both depression and raised CRP concentration predict IHD and that elevated CRP is linked with increased risk of depression. METHODS: A prospective case-control study of healthy men and women, aged 45 to 79 years, was undertaken within the United Kingdom European Prospective Investigation into Cancer (EPIC)-Norfolk study. CRP concentration was measured for 726 (fatal or nonfatal) IHD cases and 1688 matched controls who completed a baseline MDD self-assessment, defined by restricted Diagnostic and Statistical Manual of Mental Disorders, 4th Edition diagnostic criteria. RESULTS: Past-year MDD was associated with increased CRP concentration levels (4.31 mg/L for participants who reported episodes of MDD in the past year versus 3.65 mg/L for those who did not; p = .003), and the odds ratio for incident IHD associated with higher CRP concentration was 2.02 (comparing the top versus bottom quartile of CRP; 95% Confidence Interval (CI) = 1.52-2.68), adjusted for cigarette smoking, diabetes, systolic blood pressure, body mass index, and cholesterol. The association between past-year MDD and IHD was independent of CRP (odds ratio = 1.55; 95% CI = 1.01-2.37, with adjustments as above, and additionally for CRP). CONCLUSIONS: Evidence from this study is supportive of an association between MDD and CRP although it suggests that CRP does not account for the association between MDD and future IHD.

Adaptation to social adversity is associated with stroke incidence: evidence from the EPIC-Norfolk prospective cohort study.

BACKGROUND AND PURPOSE: Laboratory-based studies have suggested that individual differences in cardiovascular reactivity and stress adaptive capacity are associated with stroke incidence. We test the hypothesis that sense of coherence (SOC), a marker of social stress adaptive capacity, is associated with incident stroke in a population-based prospective cohort study. METHODS: A total of 20,629 participants, aged 41 to 80 years, in the UK European Prospective Investigation into Cancer (EPIC)-Norfolk study, who had not previously experienced a stroke, completed assessments that included SOC and details of their experience of life events during adulthood. An index of adaptation was constructed from responses to questions concerning over 80,000 adverse life events. RESULTS: During 145,000 person-years of follow-up (mean 7.1 years), 452 participants experienced either a fatal or nonfatal stroke event. A strong (as opposed to a weak) SOC was associated with a reduced rate of stroke incidence (rate ratio 0.76; 95% CI, 0.60 to 0.96) after adjustment for age, sex, pre-existing myocardial infarction, diabetes, hypertension treatment, family history of stroke, cigarette smoking, systolic blood pressure, obesity, social class, education, hostility and depression. No sex difference in this association was observed. Measures of social adversity occurrence and impact were not associated with stroke incidence, whereas faster reported adaptation to adverse event exposure was associated with a reduced rate of stroke incidence (rate ratio 0.89; 95% CI, 0.81 to 0.98; per standard deviation change in adaptation score, adjusted for age and sex). CONCLUSIONS: Stress adaptive capacity is a potentially important candidate risk factor for stroke.

A common variant of the p16(INK4a) genetic region is associated with physical function in older people.

p16(INK4a) is active in cell senescence, ageing and tumor suppression. Deletion of the small p16(INK4a)/ARF/p15(INK4b) region occurs in many cancers. We screened 25 common polymorphisms across the region and three related genes for associations with physical functioning in older people. In an initial sample of 938 (aged 65-80 years) from the EPIC study (Norfolk, UK), the rs2811712 SNP minor allele (located between the shared p16(INK4a)/ARF locus and p15(INK4b)) was associated with reduced physical impairment. This association remained after testing an additional 1319 EPIC-Norfolk samples (p-value=0.013, total n=2257), and on independent replication in the InCHIANTI study (n=709, p=0.015), and at one-sided significance in Iowa-EPESE (n=419, p=0.079). Overall (n=3372), the prevalence of severely limited physical function was 15.0% in common homozygotes and 7.0% in rare homozygotes (per minor allele odds ratio=1.48, 95% CI: 1.17-1.88, p=0.001, adjusted for age, sex and study). This estimate was similar excluding screening set 1 (OR=1.45, 95% CI: 1.09-1.92, p=0.010, n=2434). These findings require further replication, but provide the first direct evidence that the p16(INK4a)/ARF/p15(INK4b) genetic region and the senescence machinery are active in physical ageing in heterogeneous human populations. The mechanism involved may be via greater cellular restorative activity and reduced stem cell senescence.

Self-reported mental health-related quality of life and mortality in men and women in the European Prospective Investigation into Cancer (EPIC-Norfolk): a prospective population study.

OBJECTIVE: To explore the relationship between self-reported mental functional health and mortality. METHODS: Participants included 17,777 men and women aged 40 to 79 years at baseline who lived in Norfolk, UK, and had no known cardiovascular disease or cancer, and completed the anglicized Short Form 36-item questionnaire (UK SF-36) during 1996 to 2000 in the European Prospective Investigation into Cancer-Norfolk prospective population study. We examined the relationship between mental functional health derived from the mental component summary scores of the SF-36 and mortality from all causes, cardiovascular disease, cancer, and other causes during an average 6.5-year follow-up. RESULTS: There were 1065 deaths during a total of 115,550 person-years of follow-up. Impaired mental health-related quality of life was associated with increased risk of all-cause mortality in men and women. A decrease of 1 SD (10 points) in SF-36 mental component summary scores was associated with a 14% increase in all-cause mortality (hazards ratio = 1.14; 95% Confidence Interval: 1.07, 1.21) after controlling for age, gender, body mass index, systolic blood pressure, cholesterol, alcohol consumption, diabetes, smoking, social class, and physical functional health. CONCLUSION: Poor self-reported mental functional health is related to increased risk of all-cause mortality in men and women. Interpretation of this association requires further investigation.

No association between the BDNF Val66Met polymorphism and mood status in a non-clinical community sample of 7389 older adults.

Recent research has suggested that brain-derived neurotrophic factor (BDNF) may be implicated in the aetiology of mood-related phenotypes. Here we report an investigation of the association between a BDNF coding variant (Val66Met, rs6265) and mood status in a large non-clinical sample of men and women. We genotyped 7389 adult men and women, aged 41-80 years, selected from participants in the European Prospective Investigation into Cancer and Nutrition in Norfolk (EPIC-Norfolk, United Kingdom). Evidence of past year prevalent, lifetime and recurrent episodic major depressive disorder (MDD) and of past year prevalent and lifetime generalised anxiety disorder (GAD), defined by DSM-IV diagnostic criteria, was assessed through questionnaire together with a five-item version of the Mental Health Inventory (MHI-5). A total of 1214 (16.4%) participants reported lifetime MDD and 355 (4.8%) reported lifetime GAD. In this population based study we found no evidence to support an association between the BDNF gene Val66Met polymorphism and mood status.

Healthy lifestyle choices: could sense of coherence aid health promotion?

BACKGROUND: A research framework based on the personal characteristic defined by a sense of coherence (SOC) focuses on the effective use of resources to maintain good health. OBJECTIVES: To test the hypothesis that individual differences in SOC are associated with healthier lifestyle choices independently of social class and education. DESIGN AND SETTING: Cross sectional. Population based cohort study recruited through 35 general practice registers. Reported dietary intakes of alcohol, fruit and vegetables, fibre, saturated fat, non-discretionary salt (sodium), and total sugars were assessed by food frequency questionnaire. Current cigarette smoking, physical inactivity, and SOC were assessed through questionnaires. PARTICIPANTS: 7,863 men and 10,424 women. Residents of Norfolk (UK). RESULTS: Compared with participants with the weakest SOC, those with the strongest were 28% less likely to be current smokers (odds ratio 0.72 (95% confidence interval (CI), 0.58 to 0.89)), 36% less likely to be physically inactive (0.64 (0.55 to 0.75)), and reportedly consumed on average 63 g/day more fruit and vegetables (95% CI, 46 to 80), and 1.2 g/day more fibre (0.8 to 1.6). These associations were independent of age, sex, social class, and education. For physical inactivity and consumption of fruit, vegetables, and fibre, these differences exceeded those observed between the extremes of social class and education. CONCLUSIONS: Individual differences in SOC are associated with healthy lifestyle choices independently of social class and education, and may therefore aid the design of future health promotion interventions.

The shackles of misfortune: social adversity assessment and representation in a chronic-disease epidemiological setting.

Research evidence is accumulating to support an association between social adversity and the development of predisease processes and physical disease outcomes. While methodological advances have been achieved in the assessment of social adversity, significant barriers remain to their adoption in chronic disease epidemiological settings consequent upon the need to limit participant burden and restrictions imposed by cohort size and cost. A large-scale population-based cohort study, as part of the European Prospective Investigation into Cancer, Norfolk, UK, provided an opportunity to include a comprehensive postal assessment of social adversity. A total of 20,921 participants reported details of 16,031 adverse circumstances during childhood, 119,056 life events and 106,170 person-years of difficulties experienced during adulthood. Impact and adaptation indices were constructed from responses to questions regarding specific life events experienced. There was no evidence that younger participants reported more difficulties in childhood than those who were older, and no evidence of clustering of loss events involving the death of first degree relatives according to their recency. However, there was evidence of recall bias for events not involving loss with increased event rates observed in the few years immediately prior to questionnaire completion. Women reported similar events as more upsetting, and that they took longer to get over their effects, than men. Difficulties experienced in childhood, life events and difficulties in adulthood, event impact and adaptation were all associated with worse physical functional health. Reported slow adaptation to the effects of life events was associated with the largest decrement in physical functional health. These findings strengthen the rationale for including a collection of comprehensive social adversity data within chronic disease epidemiological settings and offer promise for aiding understanding of individual differences in physical disease aetiology.

Psychosocial factors and asthma in a community sample of older adults.

OBJECTIVE: The objective of this study was to investigate the associations between psychosocial factors and asthma in a population-based cohort study of older adults. METHODS: A total of 20,888 participants in the Norfolk cohort of the European Prospective Investigation into Cancer study completed assessments that included details of lifetime self-reported doctor-diagnosed asthma, mood disorder history, social adversity experience, and social support. RESULTS: Doctor-diagnosed asthma was reported by 1699 (8.1%) participants. After adjusting for age, sex, preexisting myocardial infarction, stroke, diabetes, cancer, cigarette smoking, social class, and area deprivation, the psychosocial factors most strongly (and independently) associated with asthma were major depressive disorder (P=.0001), adverse childhood circumstances (P=.005), reported impact of life events experienced in adulthood (P=.003), long-term difficulties in adulthood (P=.04), and negative aspects of confidant support (P=.002). CONCLUSION: These results demonstrate that adverse psychosocial factors cluster among older adults with asthma. These findings may have implications for guiding improvements in asthma management.

Social adversity, the serotonin transporter (5-HTTLPR) polymorphism and major depressive disorder.

BACKGROUND: Recent evidence has suggested that the short allele of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR of the human serotonin gene [SLC6A4]) is associated with increased risk of depressive disorder but only among individuals exposed to social adversity. We report an investigation designed to replicate this finding. METHODS: Data were available from a non-clinical sample of 4,175 adult men and women, ages 41-80 years, selected from participants in the European Prospective Investigation into Cancer and Nutrition in Norfolk (EPIC-Norfolk, United Kingdom) study. Evidence of past-year prevalent episodic major depressive disorder (MDD), defined by restricted DSM-IV diagnostic criteria, was assessed through questionnaire. Adverse experiences in childhood and in adulthood (during the five years preceding assessment) were also assessed through self-report. The 5-HTTLPR variant was genotyped according to published protocols. RESULTS: One-year prevalent MDD criteria were met by 298 study participants. The experience of social adversity (both in childhood and adulthood) was strongly associated with increased rates of past-year prevalent MDD. No gene by environment (GxE) interactions between the 5-HTTLPR genotype, social adversity, and MDD were observed. CONCLUSIONS: This study has not replicated a previous finding of a GxE interaction between the 5-HTTLPR genotype, social adversity, and depression.

Relation between self-reported physical functional health and chronic disease mortality in men and women in the European Prospective Investigation into Cancer (EPIC-Norfolk): a prospective population study.

PURPOSE: To explore the relationship between self-reported physical functional health and mortality. METHODS: A cohort of 17,777 men and women aged 41-80 years who completed the anglicised 36-item short-form questionnaire (UK SF-36) in 1996-2000 were followed prospectively until 2004, average 6.5 years, for mortality from all causes, from cardiovascular disease, from cancer, and from all other causes. RESULTS: During 115,527 person-years of follow-up, 1065 deaths occurred. After adjusting for age, body mass index, systolic blood pressure, cholesterol, smoking, diabetes, and social class, the relative risks (RR) for all cause mortality were 2.15 (95% CI: 1.54, 2.99) and 2.42 (1.57, 3.74), cardiovascular mortality were RR = 2.71 (1.47, 4.98) and 3.09 (1.30, 7.33), and death from other causes excluding cancer RR = 2.88 (1.43, 5.79) and 5.22 (1.21, 22.53) in men and women respectively for those who were in the lowest compared to top quintile of SF-36 scores. These associations remained unchanged after exclusion of deaths during the first two years of follow-up and were also consistent in different age groups. CONCLUSIONS: Poor self-reported physical functional health in men and women without known instances of prevalent cardiovascular disease or cancer predicts total and cardiovascular disease mortality in the general population independently of known risk factors.

Mastery, sense of coherence, and mortality: evidence of independent associations from the EPIC-Norfolk Prospective Cohort Study.

This study investigated the association between 2 distinct personal coping resources (mastery and sense of coherence) and all-cause, cardiovascular, and cancer mortality. During follow-up (up to 6 years), 994 deaths were recorded among 20,323 participants, ages 41 to 80 years, in the European Prospective Investigation into Cancer Study in the United Kingdom. A strong sense of mastery was associated with lower rates of mortality from all causes, cardiovascular disease, and cancer, after adjusting for age, sex, and prevalent chronic physical disease. The association with all-cause mortality was observed for both men and women and remained following further adjustment for cigarette smoking, social class, hostility, neuroticism, and extroversion. Analysis of the joint association between mastery and sense of coherence revealed both personal coping dispositions to be independently associated with lower rates of all-cause mortality. In addition, these data suggested that the association for mastery was specific to cardiovascular mortality, whereas the association for sense of coherence was specific to cancer mortality. These results may aid future study of coping resources as determinants of persistent well-being.

Resilience, misfortune, and mortality: evidence that sense of coherence is a marker of social stress adaptive capacity.

OBJECTIVE: The purpose of this study is to test the hypothesis that sense of coherence (SOC) distinguishes adaptive capacity to adverse event experience. METHODS: A population-based cohort of 20,921 men and women completed a postal assessment of their lifetime experience of specific adverse events and a measure of their SOC. Reports of 111,857 events allowed construction of measures of event impact and adaptation. RESULTS: Those with a weak SOC reported significantly slower adaptation to the adverse effects of their event experiences than those with a strong SOC (P<.0001). During mean follow-up of 6.7 years, 1617 deaths were recorded. A one standard deviation increase in mean adaptation score (representing slower adaptation) was associated with a 6% increase in mortality rate (P=.03) after adjusting for age and sex. Measures of event occurrence and impact were less strongly associated with SOC and were not significantly associated with mortality. CONCLUSION: These results suggest that SOC is a potential marker of an individual's social stress adaptive capacity, which is predictive of mortality.

Daytime napping and increased risk of incident respiratory diseases: symptom, marker, or risk factor?

BACKGROUND: We have identified a strong association between daytime napping and increased mortality risk from respiratory diseases, but little is known about the relationship between daytime napping and respiratory morbidity. METHODS: Data were drawn from the European Prospective Investigation into Cancer and Nutrition-Norfolk cohort. Participants reported napping habits during 1998-2000 and were followed up for respiratory disease hospital admissions until March 2009. Cox proportional hazards regression was used to examine the association between daytime napping and respiratory disease incidence risk. RESULTS: The study sample included 10,978 men and women with a mean age of 61.9 years, and a total of 946 incident respiratory disease cases were recorded. After adjustment for age, sex, social class, education, marital status, employment status, nightshift work, body mass index, physical activity, smoking, alcohol intake, self-reported general health, hypnotic drug use, habitual sleep duration, and preexisting health conditions, daytime napping was associated with an increase in the overall respiratory disease incidence risk (hazard ratio (HR) = 1.32, 95% confidence interval (CI) 1.15, 1.52 for napping <1 h; HR = 1.54, 95% CI 1.14, 2.09 for napping ≥1 h). This association was more pronounced for lower respiratory diseases, especially for the risk of chronic lower respiratory diseases (HR = 1.52, 95% CI: 1.18, 1.96 for napping <1 h; HR = 1.72, 95% CI: 1.01, 2.92 for napping ≥1 h, overall p = 0.003). CONCLUSIONS: Excessive daytime napping might be a useful marker of future respiratory disease incidence risk. Further studies are required to confirm these findings and help understand potential mechanisms.