The dose–response effect of physical activity on cancer mortality: findings from 71 prospective cohort studies

Abstract

BackgroundThe WHO recommends moderate physical activity to combat the increasing risk of death from chronic diseases. We conducted a meta-analysis to assess the association between physical activity and cancer mortality and the WHO recommendations to reduce the latter.MethodsMEDLINE and EMBASE were searched up until May 2014 for cohort studies examining physical activity and cancer mortality in the general population and cancer survivors. Combined HRs were estimated using fixed-effect or random-effect meta-analysis of binary analysis. Associated HRs with defined increments and recommended levels of recreational physical activity were estimated by two-stage random-effects dose–response meta-analysis.ResultsA total of 71 cohort studies met the inclusion criteria and were analysed. Binary analyses determined that individuals who participated in the most physical activity had an HR of 0.83 (95% CI 0.79 to 0.87) and 0.78 (95% CI 0.74 to 0.84) for cancer mortality in the general population and among cancer survivors, respectively. There was an inverse non-linear dose–response between the effects of physical activity and cancer mortality. In the general population, a minimum of 2.5 h/week of moderate-intensity activity led to a significant 13% reduction in cancer mortality. Cancer survivors who completed 15 metabolic equivalents of task (MET)-h/week of physical activity had a 27% lower risk of cancer mortality. A greater protective effect occurred in cancer survivors undertaking physical activity postdiagnosis versus prediagnosis, where 15 MET-h/week decreased the risk by 35% and 21%, respectively.ConclusionsOur meta-analysis supports that current physical activity recommendations from WHO reduce cancer mortality in both the general population and cancer survivors. We infer that physical activity after a cancer diagnosis may result in significant protection among cancer survivors.

Shared Risk Factors in Cardiovascular Disease and Cancer

“…The AICR/WCRF reports that there is convincing evidence that physical activity reduces colorectal cancer risk, and there is probable evidence that it reduces postmenopausal breast and endometrial cancers. 34,36,65 A recent meta-analysis 80 that included 71 cohort studies found that individuals who participated in the most physical activity had an HR of 0.83 (95% CI 0.79 to 0.87) and 0.78 (95% CI 0.74 to 0.84) for cancer mortality in both the general population and among cancer survivors, respectively.…”

EXercise to prevent AnthrCycline-based Cardio-Toxicity (EXACT) in individuals with breast or hematological cancers: a feasibility study protocol

“…Exercise has also been shown to reduce all-cause mortality as well as both cancer [21] and cardiovascular-related mortality [22]. Importantly, while exercise can increase aerobic fitness as well as modify traditional CVD risk factors [23], exercise may also help protect the heart from the associated cardiotoxic effects of AC-based therapy [24].…”

The Role of Exercise in Pediatric and Adolescent Cancers: A Review of Assessments and Suggestions for Clinical Implementation

“…In adults, it appears that the most effective strategies for increasing physical activity levels after treatment are individualized programs that are initiated under supervision and are later adopted into life-style behaviors in an unsupervised setting [38,51]. It is not clear whether this is an ideal strategy for childhood cancer patients, but it appears that most current pediatric cancer exercise programs implement this approach [39,40].…”