Daytime napping, sleep duration and serum C reactive protein: a population-based cohort study
Open accessAbstract
Objectives: To explore whether daytime napping and sleep duration are linked to serum C reactive protein (CRP), a pro-inflammatory marker, in an older aged British population. Design: Cross-sectional study. Setting: European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk study. Participants: A total of 5018 men and women aged 48–92 years reported their sleep habits and had serum CRP levels measured. Outcome and measures: CRP was measured (mg/L) during 2006–2011 in fresh blood samples using high-sensitivity methods. Participants reported napping habits during 2002–2004, and reported sleep quantity during 2006–2007. Multivariable linear regression models were used to examine the association between napping and log-transformed CRP, and geometric mean CRP levels were calculated. Results: After adjustment for age and sex, those who reported napping had 10% higher CRP levels compared with those not napping. The association was attenuated but remained borderline significant (β=0.05 (95% CI 0.00 to 0.10)) after further adjustment for social class, education, marital status, body mass index, physical activity, smoking, alcohol intake, self-reported health, pre-existing diseases, systolic blood pressure, hypnotic drug use, depression and in women-only hormone replacement therapy use. The geometric means (95% CI) of CRP levels were 2.38 (2.29 to 2.47) mg/L and 2.26 (2.21 to 2.32) mg/L for those who reported napping and no napping, respectively. A U-shaped association was observed between time spent in bed at night and CRP levels, and nighttime sleep duration was not associated with serum CRP levels. The association between napping and CRP was stronger for older participants, and among extremes of time spent in bed at night. Conclusions: Daytime napping was associated with increased CRP levels in an older aged British population. Further studies are needed to determine whether daytime napping is a cause for systemic inflammation, or if it is a symptom or consequence of underlying health problems.
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In over 5,000 older participants, self-reported napping was associated with higher CRP levels, particularly in older participants, but the relationship was attenuated after adjusting for health-related variables such as pre-existing diseases, blood pressure, and depression.
“Self-reported napping assessed in over 5,000 older participants was also associated with higher CRP levels, particularly in older participants, but the relationship was attenuated after adjusting for health-related variables such as pre-existing diseases, blood pressure, and depression (335).”
From The Sleep-Immune Crosstalk in Health and Disease (2019) · cites this paper as [335]
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Cites
Ohayon, M. M., Carskadon, M. A., Guilleminault, C., & Vitiello, M. V. (2004) · Sleep · doi:10.1093/sleep/27.7.1255 · Cited by 3,349 · see citing works
Effect of sleep loss on C-reactive protein, an inflammatory marker of cardiovascular risk
Meier-Ewert, H. K., Ridker, P. M., Rifai, N., Regan, M. M., Price, N. J., Dinges, D. F., & Mullington, J. M. (2004) · Journal of the American College of Cardiology · doi:10.1016/j.jacc.2003.07.050 · Cited by 1,195 · see citing works
Wareham, N. J., Jakes, R. W., Rennie, K. L., Schuit, A. J., Mitchell, J., Hennings, S., & Day, N. (2003) · Public Health Nutrition · doi:10.1079/phn2002439 · Cited by 852 · see citing works
Cardiovascular, inflammatory, and metabolic consequences of sleep deprivation
Mullington, J. M., Haack, M., Toth, M., Serrador, J. M., & Meier-Ewert, H. K. (2009) · Progress in Cardiovascular Diseases · doi:10.1016/j.pcad.2008.10.003 · Cited by 783 · see citing works
Day, N., Oakes, S., Luben, R., Khaw, K., Bingham, S., Welch, A., & Wareham, N. (1999) · Nature · doi:10.17863/cam.89388 · Cited by 780 · see citing works
Self-citationSleep Duration and Biomarkers of Inflammation
Patel, S. R., Zhu, X., Storfer-Isser, A., Mehra, R., Jenny, N. S., Tracy, R., & Redline, S. (2009) · Sleep · doi:10.1093/sleep/32.2.200 · Cited by 615 · see citing works
Mullington, J. M., Simpson, N. S., Meier-Ewert, H. K., & Haack, M. (2010) · Best Practice & Research Clinical Endocrinology & Metabolism · doi:10.1016/j.beem.2010.08.014 · Cited by 519 · see citing works
Elevated C-Reactive Protein Levels, Psychological Distress, and Depression in 73 131 Individuals
Wium-Andersen, M. K., Ørsted, D. D., Nielsen, S. F., & Nordestgaard, B. G. (2013) · JAMA Psychiatry · doi:10.1001/2013.jamapsychiatry.102 · Cited by 489 · see citing works
Tassi, P., & Muzet, A. (2000) · Sleep Medicine Reviews · doi:10.1053/smrv.2000.0098 · Cited by 458 · see citing works
Sleep and Mortality: A Population-Based 22-Year Follow-Up Study
Hublin, C., Partinen, M., Koskenvuo, M. J., & Kaprio, J. A. (2007) · SLEEP · doi:10.1093/sleep/30.10.1245 · Cited by 439 · see citing works
Baseline C-Reactive Protein Is Associated With Incident Cancer and Survival in Patients With Cancer
Allin, K. H., Bojesen, S. E., & Nordestgaard, B. G. (2009) · Journal of Clinical Oncology · doi:10.1200/jco.2008.19.8440 · Cited by 419 · see citing works
Absence of diurnal variation of C-reactive protein concentrations in healthy human subjects
Meier-Ewert, H. K., Ridker, P. M., Rifai, N., Price, N., Dinges, D. F., & Mullington, J. M. (2001) · Clinical Chemistry · doi:10.1093/clinchem/47.3.426 · Cited by 410 · see citing works
CONTRIBUTION OF CIRCADIAN PHYSIOLOGY AND SLEEP HOMEOSTASIS TO AGE-RELATED CHANGES IN HUMAN SLEEP
Dijk, D., Duffy, J. F., & Czeisler, C. A. (2000) · Chronobiology International · doi:10.1081/cbi-100101049 · Cited by 373 · see citing works
Milner, C. E., & Côté, K. A. (2009) · Journal of Sleep Research · doi:10.1111/j.1365-2869.2008.00718.x · Cited by 368 · see citing works
Heslop, P., Smith, G. D., Metcalfe, C., Macleod, J., & Hart, C. (2002) · Sleep Medicine · doi:10.1016/s1389-9457(02)00016-3 · Cited by 335 · see citing works
Peripheral Inflammatory Biomarkers and Risk of Parkinson's Disease
Chen, H., O'Reilly, E. J., Schwarzschild, M. A., & Ascherio, A. (2007) · American Journal of Epidemiology · doi:10.1093/aje/kwm260 · Cited by 317 · see citing works
Foley, D. J., Monjan, A. A., Masaki, K., Ross, W. G., Havlik, R. J., White, L. R., & Launer, L. J. (2001) · Journal of the American Geriatrics Society · doi:10.1046/j.1532-5415.2001.t01-1-49271.x · Cited by 269 · see citing works
EPIC-Norfolk: Study design and characteristics of the cohort
Day, N., Oakes, S., Luben, R., Khaw, K., Bingham, S., Welch, A., & Wareham, N. (1999) · UEA Digital Repository (University of East Anglia) · Cited by 261 · see citing works
Self-citationSuarez, E. C. (2008) · Brain, Behavior, and Immunity · doi:10.1016/j.bbi.2008.01.011 · Cited by 248 · see citing works
Foley, D. J., Vitiello, M. V., Bliwise, D. L., Ancoli‐Israel, S., Monjan, A. A., & Walsh, J. K. (2007) · American Journal of Geriatric Psychiatry · doi:10.1097/01.jgp.0000249385.50101.67 · Cited by 236 · see citing works
Siesta in Healthy Adults and Coronary Mortality in the General Population
Naska, A. (2007) · Archives of Internal Medicine · doi:10.1001/archinte.167.3.296 · Cited by 230 · see citing works
Vascular endothelial responses to altered shear stress: Pathologic implications for atherosclerosis
Chiu, J., Usami, S., & Chien, S. (2008) · Annals of Medicine · doi:10.1080/07853890802186921 · Cited by 226 · see citing works
Foley, D. J., Monjan, A. A., Masaki, K., et al. (2001) · Journal of the American Geriatrics Society · doi:10.1111/j.1532-5415.2001.49271.x · Cited by 221 · see citing works
Ferrie, J. E., Kivimaki, M., Akbaraly, T. N., Singh-Manoux, A., Miller, M. A., Gimeno, D., Kumari, M., Davey Smith, G., & Shipley, M. J. (2013) · American Journal of Epidemiology · doi:10.1093/aje/kwt072 · Cited by 218 · see citing works
Miller, M. A., Kandala, N.-B., Mika Kivimaki, B., Meena Kumari, B., Brunner, E. J., Lowe, G. D. O., Marmot, M. G., & Cappuccio, F. P. (2009) · SLEEP · doi:10.1093/sleep/32.7.857 · Cited by 205 · see citing works
Self-citationTaheri, S., Austin, D., Lin, L., Nieto, F. J., Young, T., & Mignot, E. (2007) · Sleep · doi:10.1093/sleep/30.8.991 · Cited by 189 · see citing works
Sleep Duration, Sleep Quality, and Biomarkers of Inflammation in a Taiwanese Population
Dowd, J. B., Goldman, N., & Weinstein, M. (2011) · Annals of Epidemiology · doi:10.1016/j.annepidem.2011.07.004 · Cited by 185 · see citing works
Extreme sleep durations and increased C-reactive protein: effects of sex and ethnoracial group
Grandner, M. A., Buxton, O. M., Jackson, N., Sands-Lincoln, M., Pandey, A., & Jean-Louis, G. (2013) · SLEEP · doi:10.5665/sleep.2646 · Cited by 178 · see citing works
Day Napping and Short Night Sleeping Are Associated With Higher Risk of Diabetes in Older Adults
Xu, Q., Song, Y., Hollenbeck, A., Blair, A., Schatzkin, A., & Chen, H. (2010) · Diabetes Care · doi:10.2337/dc09-1143 · Cited by 158 · see citing works
Faraut, B., Boudjeltia, K. Z., Dyzma, M., Rousseau, A., David, E., Stenuit, P., Franck, T. J., Antwerpen, P. V., Vanhaeverbeek, M., & Kerkhofs, M. (2010) · Brain Behavior and Immunity · doi:10.1016/j.bbi.2010.08.001 · Cited by 153 · see citing works
Campos, H., & Siles, X. (2000) · International Journal of Epidemiology · doi:10.1093/ije/29.3.429 · Cited by 141 · see citing works
Leng, Y., Wainwright, N. W. J., Cappuccio, F. P., Surtees, P. G., Hayat, S. A., Luben, R., Brayne, C., & Khaw, K. (2014) · American Journal of Epidemiology · doi:10.1093/aje/kwu036 · Cited by 132 · see citing works
Self-citationRuggiero, J. S., & Redeker, N. (2013) · Biological Research for Nursing · doi:10.1177/1099800413476571 · Cited by 122 · see citing works
Bursztyn, M., Ginsberg, G. M., Hammerman‐Rozenberg, R., & Stessman, J. (1999) · Archives of Internal Medicine · doi:10.1001/archinte.159.14.1582 · Cited by 118 · see citing works
Sleep Duration, Nap Habits, and Mortality in Older Persons
Cohen‐Mansfield, J., & Perach, R. (2012) · SLEEP · doi:10.5665/sleep.1970 · Cited by 103 · see citing works
Daytime Napping, Nighttime Sleeping, and Parkinson Disease
Gao, J., Huang, X., Park, Y., Hollenbeck, A. R., Blair, A. E., Schatzkin, A. G., & Chen, H. (2011) · American Journal of Epidemiology · doi:10.1093/aje/kwq478 · Cited by 102 · see citing works
Napping Is Associated with Increased Risk of Type 2 Diabetes: The Guangzhou Biobank Cohort Study
Lam, K.-B. H., Jiang, C. Q., Thomas, G. N., Arora, T., Zhang, W. S., Taheri, S., Adab, P., Lam, T. H., & Cheng, K. K. (2010) · SLEEP · doi:10.1093/sleep/33.3.402 · Cited by 101 · see citing works
Jung, K.-I., Song, C.-H., Ancoli‐Israel, S., & Barrett-Connor, E. L. (2012) · Sleep Medicine · doi:10.1016/j.sleep.2012.06.004 · Cited by 97 · see citing works
Daytime napping and mortality, with a special reference to cardiovascular disease: the JACC study
Tanabe, N., Iso, H., Seki, N., Suzuki, H., Yatsuya, H., Toyoshima, H., Tamakoshi, A., & for the JACC Study Group (2009) · International Journal of Epidemiology · doi:10.1093/ije/dyp327 · Cited by 97 · see citing works
Liukkonen, T., Räsänen, P., Ruokonen, A., Laitinen, J., Jokelainen, J., Leinonen, M., Meyer-Rochow, V. B., & Timonen, M. (2007) · Psychosomatic Medicine · doi:10.1097/psy.0b013e318157cb96 · Cited by 83 · see citing works
Jackowska, M., Meena Kumari, B., & Steptoe, A. (2013) · Psychoneuroendocrinology · doi:10.1016/j.psyneuen.2012.12.015 · Cited by 75 · see citing works
Svensson, M., Venge, P., Janson, C., & Lindberg, E. (2011) · Journal of Sleep Research · doi:10.1111/j.1365-2869.2011.00946.x · Cited by 63 · see citing works
The Siesta and Mortality: Twelve Years of Prospective Observations in 70-Year-Olds
Bursztyn, M., & Stessman, J. (2005) · SLEEP · doi:10.1093/sleep/28.3.345 · Cited by 61 · see citing works
Self-reported sleep patterns in a British population cohort
Leng, Y., Wainwright, N. W. J., Cappuccio, F. P., Surtees, P. G., Luben, R., Wareham, N. J., Brayne, C., & Khaw, K. (2014) · Sleep Medicine · doi:10.1016/j.sleep.2013.10.015 · Cited by 53 · see citing works
Self-citationAhmadi‐Abhari, S., Luben, R., Wareham, N. J., & Khaw, K. (2013) · European Journal of Clinical Investigation · doi:10.1111/eci.12116 · Cited by 38 · see citing works
Self-citationSelf‐reported sleep duration – what does it mean?
Lavie, P. (2009) · Journal of Sleep Research · doi:10.1111/j.1365-2869.2009.00813.x · Cited by 19 · see citing works
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The Sleep-Immune Crosstalk in Health and Disease
Besedovsky, L., Lange, T., & Haack, M. (2019) · Physiological Reviews · doi:10.1152/physrev.00010.2018 · Cited by 1,479 · see citing works
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Mantua, J., & Spencer, R. M. C. (2015) · Sleep Medicine · doi:10.1016/j.sleep.2015.06.014 · Cited by 45 · see citing works
- Authors
- Leng, Y., Ahmadi-Abhari, S., Wainwright, N. W. J., Cappuccio, F. P., Surtees, P. G., Luben, R., Brayne, C., & Khaw, K.-T.
- Affiliations
- University of Cambridge (GB)
- Department of Public Health and Primary Care, Strangeways Research Laboratory, University of Cambridge, Cambridge, UK
- University of Warwick (GB)
- Corresponding author
- Leng, Yue
- Venue
- BMJ Open
- Publisher
- BMJ
- Published
- 2014-11
- Volume
- 4
- Issue
- 11
- Pages
- e006071
- ISSN
- 2044-6055 (ISSN-L)
- PMC
- PMC4244397
- OpenAlex
- W2134023549
- Cited by
- 80
- References
- 47
- Citations by year
- 2026: 5 · 2025: 9 · 2024: 10 · 2023: 7 · 2022: 9 · 2021: 15 · 2020: 2 · 2019: 4 · 2018: 5 · 2017: 7 · 2016: 5 · 2015: 2
- FWCI
- 6.49
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- cc-by
- Locations
- BMJ Open (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Apollo (University of Cambridge) (submittedVersion, cc-by)
- HighWire Press Open Archive (submittedVersion)
- Warwick Research Archive Portal (University of Warwick) (submittedVersion)
- Funders
- Cancer Research UK (C864/A2883, C/864/A8257)
- National Institute for Health and Care Research (NF-SI-0512-10114, NF-SI-0611-10084)
- Cambridge Overseas Trust
- Economic and Social Research Council (ES/K002910/1)
- Topics
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
- Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
- Keywords
- daytime napping, sleep duration, C-reactive protein, systemic inflammation, older adults, time in bed, nocturnal sleep, EPIC-Norfolk cohort
- MeSH terms
- Aged, Aged, 80 and over, C-Reactive Protein, Cross-Sectional Studies, Female, Habits, Humans, Male, Middle Aged, Surveys and Questionnaires, Sleep, Time Factors, Cohort Studies
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