Recreational Physical Activity and Epithelial Ovarian Cancer: A Case-Control Study, Systematic Review, and Meta-analysis

Abstract

It remains unclear whether physical activity is associated with epithelial ovarian cancer risk. We therefore examined the association between recreational physical activity and risk of ovarian cancer in a national population-based case-control study in Australia. We also systematically reviewed all the available evidence linking physical activity with ovarian cancer to provide the best summary estimate of the association. The case-control study included women ages 18 to 79 years with a new diagnosis of invasive (n = 1,269) or borderline (n = 311) epithelial ovarian cancer identified through a network of clinics, physicians, and state cancer registries throughout Australia. Controls (n = 1,509) were randomly selected from the national electoral roll and were frequency matched to cases by age and state. For the systematic review, we identified eligible studies using Medline, the ISI Science Citation Index, and manual review of retrieved references, and included all case-control or cohort studies that permitted assessment of an association between physical activity (recreational/ occupational/sedentary behavior) and histologically confirmed ovarian cancer. Meta-analysis was restricted to the subset of these studies that reported on recreational physical activity. In our case-control study, we observed weakly inverse or null associations between recreational physical activity and risk of epithelial ovarian cancer overall. There was no evidence that the effects varied by tumor behavior or histologic subtype. Twelve studies were included in the metaanalysis, which gave summary estimates of 0.79 (95% confidence interval, 0.70-0.85) for case-control studies and 0.81 (95% confidence interval, 0.57-1.17) for cohort studies for the risk of ovarian cancer associated with highest versus lowest levels of recreational physical activity. Thus, pooled results from observational studies suggest that a modest inverse association exists between level of recreational physical activity and the risk of ovarian cancer. (Cancer Epidemiol Biomarkers Prev 2007;16(11):2321 -30)

Aspirin, Nonsteroidal Anti-inflammatory Drugs, and the Risks of Cancers of the Esophagus

“…We aimed for similar numbers of male cases and controls in each stratum of age and state; female controls were intentionally oversampled at all ages to accommodate their simultaneous enrollment in a parallel case-control study of ovarian cancer (48). Of 3,258 potentially eligible control participants who were contacted and invited to participate, 175 were excluded because they were deceased (16), too ill (61), or unable to read or write in English (98), and 41 were lost to follow-up in the interval between initial contact and participation.…”

Estágios de mudança de comportamento para a atividade física em adolescentes

“…Evidências disponíveis indicam que a exposição a baixos níveis de atividade física constitui fator de risco para doenças crônicas não transmissíveis, como a obesidade, o diabetes, as doenças cardiovasculares e certos tipos de neoplasias (MONNINKHOF et al, 2007;NOCON et al, 2008;OLSEN et al, 2007;QIN et al, 2010;WAREHAM et al, 2005). Apesar do reconhecimento quanto à importância que as atividades físicas podem desempenhar na prevenção de doenças e melhoria da qualidade de vida, estudos têm relatado uma elevada prevalência de níveis insuficientes de prática de atividades físicas em todos os grupos populacionais, inclusive entre crianças e adolescentes (BASTOS et al, 2008;HOELSCHER et al, 2009).…”

Physical Activity and its Relation to Cancer Risk: Updating the Evidence

“…More than 20 studies have been conducted on physical activity and ovarian cancer demonstrating inconsistent findings (Olsen et al, 2007;WCRF/AICR, 2007;Friedenreich et al, 2010a;Speck et al, 2011). The reviews concluded that there was a modest inverse relationship between physical activity and ovarian cancer development with about 10-20% reduction of the risk.…”

“…Estimation of a dose-response trend showed inconsistency for all types of activity, i.e. the beneficial effect of physical activity was somewhat stronger for recreational activity than occupational activity (Olsen et al, 2007). It is worthwhile to add that two studies (Zhang et al, 2004, Patel et al, 2006 reported about 50% increase in ovarian cancer risk among women sitting ≥6 hours daily.…”