Sleep duration and napping in relation to colorectal and gastric cancer in the MCC-Spain study
Sleep duration is a novel and potentially modifiable risk factor for cancer. We evaluated the association of self-reported sleep duration and daytime napping with odds of colorectal and gastric cancer. We included 2008 incident colorectal cancer cases, 542 gastric cancer cases and 3622 frequency-matched population controls, recruited in the MCC-Spain case-control study (2008-2013). Sleep information, socio-demographic and lifestyle characteristics were obtained through personal interviews. Multivariable adjusted logistic regression models were used to estimate odds ratios (OR) with 95% confidence intervals (CI) for cancer, across categories of sleep duration (? 5, 6, 7, 8, ? 9 hours/day), daytime napping frequency (naps/week) and duration (minutes/nap). Compared to 7 hours of sleep, long sleep was associated with increased odds of colorectal (OR?9 hours: 1.59; 95%CI 1.30-1.94) and gastric cancer (OR?9 hours: 1.95; 1.37-2.76); short sleep was associated with increased odds of gastric cancer (OR?5 hours: 1.32; 0.93-1.88). Frequent and long daytime naps increased the odds of colorectal (OR6-7 naps/week, ?30 min: 1.32; 1.14-1.54) and gastric cancer (OR6-7 naps/week, ?30 min: 1.56; 1.21-2.02). Effects of short sleep and frequent long naps were stronger among participants with night shift-work history. Sleep and circadian disruption may jointly play a role in the etiology of colorectal and gastric cancer. ; Funding: The study was funded by the "Accion Transversal del Cancer", approved on the Spanish Ministry Council on 11 October 2007, by the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/0533, PI08/1359, PI09/00773-Cantabria, PI09/01286-León, PI09/01903-Valencia, PI09/02078-Huelva, PI09/01662-Granada, PI11/01403, PI11/01889-FEDER, PI11/00226, PI11/01810, PI11/02213, PI12/00488, PI12/00265, PI12/01270, PI12/00715, PI12/00150), by the Fundación Marqués de Valdecilla (API 10/09), by the ICGC International Cancer Genome Consortium CLL (The ICGC CLL-Genome Project is funded by Spanish Ministerio de Economía y Competitividad (MINECO) through the Instituto de Salud Carlos III (ISCIII) and Red Temática de Investigación del Cáncer (RTICC) del ISCIII (RD12/0036/0036)), by the Junta de Castilla y León (LE22A10-2), by the Consejería de Salud of the Junta de Andalucía (2009-S0143), by the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10), by the Recercaixa (2010ACUP 00310), by the European Commission grants FOOD-CT-2006-036224-HIWATE, by the Spanish Association Against Cancer (AECC) Scientific Foundation, by the Catalan Government DURSI grant 2009SGR1489. KP received a predoctoral grant PFIS (FI09/00385). MCT is funded by a Ramón y Cajal fellowship (RYC-2017-01892) from the Spanish Ministry of Science, Innovation and Universities and cofunded by the European Social Fund. ISGlobal acknowledges support from the Spanish Ministry of Science and Innovation through the "Centro de Excelencia Severo Ochoa 2019–2023" Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program. Agency for Management of University and Research Grants (AGAUR) of the Catalan Government grant 2017SGR723. Spanish Association Against Cancer (AECC) Scientific Foundation. DC is supported by Spanish Ministry of Economy and Competitiveness—Carlos III Institute of Health cofunded by FEDER funds/European Regional Develpment Fund (ERDF)—a way to build Europe (PI17/01280), the Centro de Investigacion Biomedica en Red: Epidemiologia y Salud Publica (CIBERESP, Spain) and the Agencia de Gestio d'Ajuts Universitaris i de Recerca (AGAUR), CERCA Programme/Generalitat de Catalunya for institutional suport (2017SGR1085). VM is funded by the Agency for Management of University and Research Grants (AGAUR) of the Catalan Government grant 2017SGR723; Instituto de Salud Carlos III, co-funded by FEDER funds—a way to build Europe—; Spanish Association Against Cancer (AECC) Scientific Foundation. Sample collection of this work was supported by the Xarxa de Bancs de Tumors de Catalunya sponsored by Pla Director d'Oncología de Catalunya (XBTC)", Plataforma Biobancos PT13/0010/0013" and ICOBIOBANC, sponsored by the Catalan Institute of Oncology. We thank CERCA Program, Generalitat de Catalunya for institutional support.