Randomised controlled trial of a home-based physical activity intervention in breast cancer survivors

Abstract

BackgroundTo improve adherence to physical activity (PA), behavioural support in the form of behavioural change counselling may be necessary. However, limited evidence of the effectiveness of home-based PA combined with counselling in breast cancer patients exists. The aim of this current randomised controlled trial with a parallel group design was to evaluate the effectiveness of a home-based PA intervention on PA levels, anthropometric measures, health-related quality of life (HRQoL), and blood biomarkers in breast cancer survivors.MethodsEighty post-adjuvant therapy invasive breast cancer patients (age = 53.6 ± 9.4 years; height = 161.2 ± 6.8 cm; mass = 68.7 ± 10.5 kg) were randomly allocated to a 6-month home-based PA intervention or usual care. The intervention group received face-to-face and telephone PA counselling aimed at encouraging the achievement of current recommended PA guidelines. All patients were evaluated for our primary outcome, PA (International PA Questionnaire) and secondary outcomes, mass, BMI, body fat %, HRQoL (Functional assessment of Cancer Therapy-Breast), insulin resistance, triglycerides (TG) and total (TC), high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C) cholesterol were assessed at baseline and at 6-months.ResultsOn the basis of linear mixed-model analyses adjusted for baseline values performed on 40 patients in each group, total, leisure and vigorous PA significantly increased from baseline to post-intervention in the intervention compared to usual care (between-group differences, 578.5 MET-min∙wk−1, p = .024, 382.2 MET-min∙wk−1, p = .010, and 264.1 MET-min∙wk−1, p = .007, respectively). Both body mass and BMI decreased significantly in the intervention compared to usual care (between-group differences, −1.6 kg, p = .040, and −.6 kg/m2, p = .020, respectively). Of the HRQoL variables, FACT-Breast, Trial Outcome Index, functional wellbeing, and breast cancer subscale improved significantly in the PA group compared to the usual care group (between-group differences, 5.1, p = .024; 5.6, p = .001; 1.9 p = .025; and 2.8, p = .007, respectively). Finally, TC and LDL-C was significantly reduced in the PA group compared to the usual care group (between-group differences, −.38 mmol∙L−1, p = .001; and −.3 mmol∙L−1, p = .023, respectively).ConclusionsWe found that home-based PA resulted in significant albeit small to moderate improvements in self-reported PA, mass, BMI, breast cancer specific HRQoL, and TC and LDL-C compared with usual care.ClinicalTrials.gov identifierNCT02408107 (March 25, 2015)

Changes in metabolic risk, insulin resistance, leptin and adiponectin following a lifestyle intervention in overweight and obese breast cancer survivors

“…Very recently, Lahart et al (2016) evaluated the effectiveness of a home-based PA intervention on blood biomarkers and found significant decreases in total cholesterol and LDL-C when they compared their intervention group to their control group, which corroborates our findings; however, they did not find any difference for triglycerides. Another randomised clinical trial, which investigated the effects of a combined exercise and dietary intervention on health outcomes associated with long-term prognosis in overweight BC survivors, also described a significant decrease in total cholesterol (Scott et al, 2013).…”

“…Glucose homeostasis may affect BC prognosis (Champ et al, 2012;Erickson et al, 2011;Goodwin et al, 2002); however, the studies that evaluated the effect of lifestyle interventions, including exercise offered to BC survivors, on glucose homeostasis have shown inconsistent results (Befort et al, 2012;Fairey et al, 2003;Irwin et al, 2009;Lahart et al, 2016;Ligibel et al, 2008;Schmitz et al, 2005;Scott et al, 2013). The significant decreases in fasting blood glucose and insulin resistance in our study are not in line with the absence of between-group differences previously described in randomised clinical trials in which intervention groups were compared to control groups (Fairey et al, 2003;Lahart et al, 2016;Ligibel et al, 2008;Schmitz et al, 2005) on fasting insulin were even more contradictory, whereas three studies found no between-group differences (Fairey et al, 2003;Lahart et al, 2016;Schmitz et al, 2005), one study found a borderline between-group difference in favour of the exercise group (Irwin et al, 2009) Notes.QR: quartile range, (P25-P75); IGFl: insulin growth factor 1; HOMA-IR: homeostasis model assessment of insulin.…”

“…Several biological mechanisms, including endogenous reproductive hormones, chronic inflammation and metabolic changes such as insulin resistance, have been proposed to explain the effects of adiposity and PA on BC prognosis (Calle & Kaaks, 2004;Champ, Volek, Siglin, Jin, & Simone, 2012;Neilson, Friedenreich, Brockton, & Millikan, 2009;Patterson et al, 2013). Several intervention studies have already been implemented to reach this goal (Befort et al, 2012;Fairey et al, 2003;Irwin et al, 2009;Lahart, Metsios, Nevill, Kitas, & Carmichael, 2016;Ligibel et al, 2008;Schmitz, Ahmed, Hannan, & Yee, 2005;Scott et al, 2013); nevertheless, due to the heterogeneity of their results, it is difficult to draw clear conclusions about the effects that lifestyle changes may have on lipid profiles, insulin resistance or adipokine levels. Studies in BC survivors have described a high prevalence of comorbid conditions in this population, which are likely to affect total mortality and also BC-specific mortality (Braithwaite et al, 2012;Nechuta et al, 2013;Patnaik, Byers, DiGuiseppi, Dabelea, & Denberg, 2011;.…”

“…However, intervention studies, involving the use of biomarkers, are still needed to better understand how modifiable lifestyle factors such as PA and adiposity may play a role in the mechanisms previously mentioned. Several intervention studies have already been implemented to reach this goal (Befort et al, 2012;Fairey et al, 2003;Irwin et al, 2009;Lahart, Metsios, Nevill, Kitas, & Carmichael, 2016;Ligibel et al, 2008;Schmitz, Ahmed, Hannan, & Yee, 2005;Scott et al, 2013); nevertheless, due to the heterogeneity of their results, it is difficult to draw clear conclusions about the effects that lifestyle changes may have on lipid profiles, insulin resistance or adipokine levels. For this reason, we designed a one-arm pre-post intervention study offering diet and exercise sessions three times per week, over 12 weeks, to early-stage BC survivors having recently finished their main treatment.…”

Protocol for Moving On: a randomized controlled trial to increase outcome expectations and exercise among breast cancer survivors

“…For example, in one study, it took 12 months to recruit 40 participants at clinic follow-up visits (Fields, Richardson, Hopkinson, & Fenlon, 2016), and in another study, it took 23 months to recruit 210 participants through the mail (Befort et al, 2014). Retention will be considered feasible if attrition is less than 17%, which is comparable to other home-based exercise interventions for breast cancer survivors in which attrition ranged from 13% to 20% (Lahart, Metsios, Nevill, Kitas, & Carmichael, 2016;Pinto, Papandonatos, & Goldstein, 2013;Pinto, Rabin, Abdow, & Papandonatos, 2008;Rabin, Pinto, Dunsiger, Nash, & Trask, 2009).…”