RESUMO
BACKGROUND: Lignans - oestrogenic substances present in various foods - are associated with postmenopausal breast cancer risk, but not much is known regarding their effects on survival. METHODS: In a follow-up study of 2653 postmenopausal breast cancer patients diagnosed between 2001 and 2005, vital status and causes of death were verified through end of 2009. Hazard ratios (HRs) and 95% confidence intervals (CIs) for estimated enterolignans, lignan-rich foods, and dietary fibre in relation to overall survival (OS) and breast cancer-specific survival (BCSS) were assessed using Cox proportional hazards models stratified by age at diagnosis and adjusted for prognostic/confounding factors. RESULTS: Median follow-up time was 6.4 years, and 321 women died, 235 with breast cancer. High estimated enterolactone and enterodiol levels were associated with significantly lower overall mortality (highest quintile, HR=0.60, 95% CI=0.40-0.89, P(Trend)=0.02 and HR=0.63, 95% CI=0.42-0.95, P(Trend)=0.02, respectively). Fibre intake was also associated with a significantly lower overall mortality. Differentiated by median fibre intake, associations with estimated enterolignans were still evident at low but not high fibre intake. There was no effect modification by oestrogen receptor status and menopausal hormone therapy. CONCLUSION: Postmenopausal breast cancer patients with high estimated enterolignans may have a better survival.
Assuntos
Neoplasias da Mama/metabolismo , Fibras na Dieta/metabolismo , Alimentos , Lignanas/metabolismo , Pós-Menopausa , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Análise de SobrevidaRESUMO
The objective of this study was to provide a systematic review and meta-analysis of studies on the relationship between body mass index (BMI) and leukocyte telomere length (LTL). Relevant studies were identified by a systematic search of MEDLINE, Embase and Web of Knowledge databases. Pooled correlation and regression coefficients were calculated using meta-analysis methods for both cross-sectional and longitudinal studies. Studies without suitable data for meta-analysis were summarized separately. Overall, 29 studies were included, of which 16 were eligible for meta-analysis, including two longitudinal studies. The majority of studies reported an inverse relationship between BMI and telomere length. For cross-sectional studies, the pooled estimates for correlation and regression coefficients were -0.057 (95% confidence interval [CI]: -0.102 to -0.012) and -0.008 kBP kg m⻲ (95% CI: -0.016 to 0.000), respectively. The two longitudinal studies were small (70 and 311 subjects), covered different age ranges and yielded inconsistent results. No evidence of any gender difference was observed. Despite some variation between studies and very limited data from longitudinal studies, the results of this meta-analysis suggest a biologically plausible inverse association between BMI and LTL in adults. However, the associations require clarification, in particular by large longitudinal studies with careful control for possible confounding factors in overall, age- and sex-specific analyses.