RESUMO
BACKGROUND: Both overweight/obesity and a Western lifestyle are associated with a poorer prognosis in women with breast cancer. The primary aim of this analysis was to examine the effect of a telephone-delivered lifestyle intervention program on reducing body weight and waist circumference, decreasing cardiovascular risk factors and improving lifestyle. DESIGN: Data is derived from an open-label, randomized, controlled phase III study that evaluated two chemotherapy regimens and the impact of a 2-year lifestyle intervention on disease-free survival and secondary outcomes in women with intermediate-risk to high-risk breast cancer. Initially, 2292 women with a body mass index (BMI) between 24 and 40 kg/m2 were randomized into one of two arms of the lifestyle intervention study. After accounting for dropout, 1785 participants remained: 776 in the intervention group (IG) who received a telephone-delivered lifestyle intervention supported by mailed materials, and 1009 in the low-level intervention group (LLIG) who received only mailed educational materials with general recommendations for a healthy lifestyle. Body weight, waist circumference, dietary intake, physical activity, and cardiovascular disease risk parameters were measured repeatedly throughout the intervention and a subsequent 2-year follow-up period. Linear mixed models for repeated measures were used to assess differences in study outcomes between the LLIG and IG at each measured time point. RESULTS: IG participants showed a mean weight loss of -2.7 kg (kg) (versus +0.4 kg, LLIG) at 6 months, -2.8 kg (vs. +0.8 kg, LLIG) at 12 months and -1.8 kg at 24 months (versus +0.9 kg, LLIG). Significant between-group differences for weight loss and reduced waist circumference were observed at all time points until the end of the lifestyle intervention (all p-values < 0.0001), including post-intervention. Reduced energy intake and a higher alternate healthy eating index (AHEI) score in the IG was detected during the lifestyle intervention (AHEI at 24 months: IG 49.1% versus LLIG 42.0%, p < 0.001). Modest significant improvements in several cardiovascular risk factors were observed during the intervention, including fasting plasma glucose, HbA1c, systolic and diastolic blood pressure, and lipids. CONCLUSIONS: A mainly telephone-delivered lifestyle intervention program can reduce body weight and waist circumference, improve diet quality, and decrease cardiometabolic risk in women with overweight/obesity and newly diagnosed, human epidermal growth factor receptor 2 (HER2)/neu-negative, intermediate-risk to high-risk breast cancer. Weight loss, reduced waist circumference and improved dietary patterns were maintained for up to two years post-intervention. TRIAL REGISTRATION: The protocol was registered under the EU Clinical Trials Register, https://www.clinicaltrialsregister.eu/, identifier: 2008-005453-38.
RESUMO
BACKGROUND: There is little evidence that dietary supplements are beneficial for patients with breast cancer; therefore, they are usually not recommended by treatment guidelines. The aim of the present analysis was to assess the prevalence of dietary supplement (DS) intake among women before and after a breast cancer diagnosis. METHODS: Participants in the SUCCESS C lifestyle intervention study, a randomized controlled trial in women with newly diagnosed intermediate- to high-risk breast cancer, completed two questionnaires on dietary supplement intake 24 months (QS1) and 48 months (QS2) after beginning the lifestyle intervention. The study was registered on 12.17.2008 under the EU Clinical Trials Register https://www.clinicaltrialsregister.eu/ , trial registration number: 2008-005453-38. The questionnaires collected data on DS intake during the 5-year period prediagnosis (QS1) and in the period postdiagnosis (QS2). Multivariate logistic regression models were fitted to examine differences in DS intake between the two intervention groups. The groups were then pooled to examine differences in DS use between the prediagnostic and postdiagnostic period. RESULTS: A total of 320 questionnaires from 58.5% of intervention group completers and 416 questionnaires from 46.6% of low-level intervention group completers were included in the analysis. Overall, 20.2% of all respondents reported taking DS prior to their diagnosis. After a cancer diagnosis, the percentage of women taking DS significantly increased to 56.4% (p for time effect < 0.0001). No differences in DS intake between the intervention groups were observed. Single or combined preparations of vitamins and minerals/trace elements were the most frequently reported supplements. Notably, a 9-fold increase in vitamin D intake was reported postdiagnosis, where the proportion of women increased from 3.8 to 34.5%. CONCLUSION: A 3-fold increase in the reported intake of dietary supplements was seen in women after a breast cancer diagnosis. These observations underscore the need to incorporate patient education surrounding the use of dietary supplements in a treatment care plan, particularly addressing the negligible benefits as well as the potential risks and treatment interactions.