title: Measured cardiorespiratory fitness and self-reported physical activity: associations with cancer risk and death in a long-term prospective cohort study.
abstract: Physical activity is inversely associated with risk of some cancers. The relation with cancer-specific death remains uncertain. Mainly, studies on relationships between physical activity and cancer are based on self-reported physical activity (SPA). Hereby, we examined whether measured cardiorespiratory fitness (CRF) is associated with cancer risk, mortality, and case fatality. We also describe relationships between SPA and these outcomes, and between CRF and SPA. A cohort of 1997 healthy Norwegian men, aged 40-59 years at inclusion in 1972-75, was followed throughout 2012. At baseline, CRF was objectively measured. SPA (leisure time and occupational) was obtained through a questionnaire. Relationships between CRF or SPA, and the outcomes were estimated using Cox regression, adjusted for age, body mass index (BMI), and smoking. Pearson correlation coefficients evaluated agreements between CRF and SPA. During follow-up, 758 men were diagnosed with cancer and 433 cancer deaths occurred. Analyses revealed lower cancer risk (Hazard ratio [HR] 0.85, 95% confidence intervals [CI]: 0.68-1.00), mortality (HR 0.68, 95% CI: 0.53-0.88), and case fatality (HR 0.74, 95% CI: 0.57-0.96), in men with high CRF compared to low CRF. Light leisure time SPA was associated with lower cancer risk (HR 0.70, 95% CI: 0.56-0.86) and mortality (HR 0.64 95% CI: 0.49-0.83), whereas strenuous occupational SPA was associated with higher risks (HR 1.42, 95% CI: 1.13-1.78 and HR 1.45, 95% CI: 1.09-1.93). Correlations between CRF and SPA were 0.351 (P < 0.001) and -0.106 (P < 0.001) for leisure time and occupational SPA, respectively. A high midlife CRF may be beneficial for cancer risk, cancer mortality, and case fatality.
authors.affiliation: Department of Research, Cancer Registry of Norway, PB 5313 Majorstuen, Oslo, N-0304, Norway.
authors.forename: Trude E
authors.initials: TE
authors.lastname: Robsahm
authors.affiliation: Oslo centre for biostatistics and epidemiology, Oslo University Hospital, Pb 4950 Nydalen, Oslo, 0424, Norway.
authors.forename: Ragnhild S
authors.initials: RS
authors.lastname: Falk
authors.affiliation: Oslo Ischemia study, Oslo University Hospital, Oslo, Norway.
authors.forename: Trond
authors.initials: T
authors.lastname: Heir
authors.affiliation: Oslo centre for biostatistics and epidemiology, Oslo University Hospital, Pb 4950 Nydalen, Oslo, 0424, Norway.
authors.forename: Leiv
authors.initials: L
authors.lastname: Sandvik
authors.affiliation: Department of Research, Cancer Registry of Norway, PB 5313 Majorstuen, Oslo, N-0304, Norway.
authors.forename: Linda
authors.initials: L
authors.lastname: Vos
authors.affiliation: Oslo Ischemia study, Oslo University Hospital, Oslo, Norway.
authors.forename: Jan E
authors.initials: JE
authors.lastname: Erikssen
authors.affiliation: Department of Research, Cancer Registry of Norway, PB 5313 Majorstuen, Oslo, N-0304, Norway.|Department of Public Health and General Practice, Norwegian University of Science and Technology, PB 8905, Trondheim, 7491, Norway.
authors.forename: Steinar
authors.initials: S
authors.lastname: Tretli
mesh_terms: D000328:Adult; D000368:Aged; D000072599:Cardiorespiratory Fitness; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009369:Neoplasms / Q000453:epidemiology* / Q000209:etiology* / Q000401:mortality; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D057566:Self Report
keywords: Cardiorespiratory fitness; cancer; fatality; mortality; physical activity; risk