Estimation of physical activity intensity cut-points using accelerometry in breast cancer survivors and age-matched controls

Perceived autonomy support from healthcare professionals and physical activity among breast cancer survivors: A propensity score analysis

The majority of women treated for breast cancer are physically inactive although physical activity (PA) could attenuate many adverse effects of cancer and treatment. Autonomy support from healthcare professionals may improve PA initiation, adherence and maintenance. This study aimed to determine, using a causal inference approach, whether or not perceived autonomy support (PAS) from healthcare professionals is associated with light, moderate, and vigorous intensity PA among women treated for breast cancer. Data were drawn from the longitudinal study "Life After Breast Cancer: Moving On" (n = 199). PAS was measured with the Health Care Climate Questionnaire and PA was assessed using GT3X triaxial accelerometers. Associations between PAS and PA were estimated with linear regressions and adjusted estimations were obtained using propensity score-based inverse probability of treatment weights (IPTW). Results reveal no association between PAS and PA of light ([Formula: see text](95%CI) = -0.09 (-0.68, 0.49)), moderate ([Formula: see text] (95%CI) = -0.03 (-0.17, 0.11)), or vigorous ([Formula: see text](95%CI) = 0.00 (-0.03, 0.02)) intensity. Different forms of engagement and support by healthcare professionals should be explored to identify the best intervention targets to encourage women to adopt and maintain regular PA in the cancer continuum.

Using ecological momentary assessment to understand associations between daily physical activity and symptoms in breast cancer patients undergoing chemotherapy

PURPOSE

Understanding real-time relationships between physical activity (PA) and symptoms during chemotherapy (CT) could have important implications for intervention. This study used ecological momentary assessment to examine the relationship between objective PA and symptoms during CT.

METHODS

Breast cancers patients (n = 67; M_age = 48.6 (SD = 10.3)) participated in data collection at three time points during CT: beginning, middle, and end. At each time point, participants answered four prompts assessing symptoms and wore an accelerometer for 10 days (3 days pre-CT, day of CT, and 6 days post-CT). Multilevel linear regression models examined the between- and within-person associations between moderate to vigorous (MVPA) and light-intensity physical activity (LPA) and same and next-day symptom ratings controlling for covariates.

RESULTS

On days when individuals engaged in more LPA or MVPA, separately, they reported improved affect, anxiety, fatigue, physical functioning (walking and activities of daily living), pain, and cognition that day (p < 0.001 for all). Findings were consistent for next-day symptom ratings with the exception that only previous day LPA was related to next-day fatigue and neither LPA nor MVPA were related to next-day cognition (p < 0.001 for all). No between-person effects were found.

CONCLUSIONS

Within person higher than usual PA on a given day, regardless of intensity, is associated with improved symptoms ratings on the current and next day.

IMPLICATIONS FOR CANCER SURVIVORS

Encouraging breast cancer patients undergoing CT to engage in daily PA could help manage CT-associated symptoms.

A comparison of total and domain-specific sedentary time in breast cancer survivors and age-matched healthy controls

Breast cancer survivors (BCS) engage in more sedentary behavior (SED) than those without cancer. However, the context in which SED is accrued is unknown. The purpose of this study is to examine differences in total and domain-specific SED of BCS and healthy controls. 20 BCS and 20 age-matched, healthy controls wore ActiGraph GT3X + accelerometers to measure SED and activity. Participants self-reported SED for transportation, occupational, screen time and leisure purposes. Multiple linear regressions were used to estimate differences in SED between BCS and controls. BCS spent significantly more time watching TV (152.4 vs. 60.3; p < 0.01) and less time in total SED (490.8 vs. 587.4; p = 0.046) and other leisure activities (57.6 vs. 106.9; p < 0.01) than healthy controls. BCS engage in more TV watching and less time in other leisure activities than controls, thus interventions should focus on reducing TV time. Understanding facilitators of TV viewing is needed to determine specific intervention targets.

Accelerometer output and its association with energy expenditure in persons with mild-to-moderate Parkinson's disease

OBJECTIVE

This study examined the association between ActiGraph accelerometer output and energy expenditure across different speeds of walking in persons with Parkinson's disease (PD), and further generated cut-points that represent a metric for quantifying time spent in moderate-to-vigorous physical activity (MVPA) among persons with PD.

METHODS

The sample included 30 persons with mild-to-moderate PD (Hoehn and Yahr stages 2-3) and 30 adults without PD matched by sex and age. All participants completed 5 minutes of quiet, seated rest and then underwent three, 6-minute bouts of walking on a treadmill at three different speeds relative to the individual's self-selected pace. Activity counts were measured using an ActiGraph accelerometer worn at the waist level on the least affected side for persons with PD and the dominant side for controls. The rate of oxygen consumption, or energy expenditure, was measured using a portable, open-circuit spirometry system.

RESULTS

Our results indicated a strong association between activity counts and energy expenditure for persons with PD (R2 = 0.87) and controls (R2 = 0.89). However, the significant difference in slopes resulted in a lower cut-point of 1,354 counts·min-1 for persons with PD than the cut-point of 2,010 counts·min-1 for controls.

CONCLUSION

Our results support the application of the disease-specific cut-point for quantifying the amount of time spent in MVPA using ActiGraph accelerometers among persons with mild-to-moderate PD. Such an application may provide accurate estimates of MVPA in this population, and better inform future research examining the possible determinants and consequences of physical activity as well as testing of interventions for changing MVPA in PD.

Development and Evaluation of an Accelerometer-Based Protocol for Measuring Physical Activity Levels in Cancer Survivors: Development and Usability Study

Background

The collection of self-reported physical activity using validated questionnaires has known bias and measurement error.

Objective

Accelerometry, an objective measure of daily activity, increases the rigor and accuracy of physical activity measurements. Here, we describe the methodology and related protocols for accelerometry data collection and quality assurance using the Actigraph GT9X accelerometer data collection in a convenience sample of ovarian cancer survivors enrolled in GOG/NRG 0225, a 24-month randomized controlled trial of diet and physical activity intervention versus attention control.

Methods

From July 2015 to December 2019, accelerometers were mailed on 1337 separate occasions to 580 study participants to wear at 4 time points (baseline, 6, 12, and 24 months) for 7 consecutive days. Study staff contacted participants via telephone to confirm their availability to wear the accelerometers and reviewed instructions and procedures regarding the return of the accelerometers and assisted with any technology concerns.

Results

We evaluated factors associated with wear compliance, including activity tracking, use of a mobile app, and demographic characteristics with chi-square tests and logistic regression. Compliant data, defined as ≥4 consecutive days with ≥10 hours daily wear time, exceeded 90% at all study time points. Activity tracking, but no other characteristics, was significantly associated with compliant data at all time points (P<.001). This implementation of data collection through accelerometry provided highly compliant and usable activity data in women who recently completed treatment for ovarian cancer.

Conclusions

The high compliance and data quality associated with this protocol suggest that it could be disseminated to support researchers who seek to collect robust objective activity data in cancer survivors residing in a wide geographic area.

From accelerometer output to physical activity intensities in breast cancer patients

OBJECTIVES

We aimed to investigate accelerometer output corresponding to physical activity intensity cut-points based on percentage of peak oxygen consumption (%VO₂peak) and Metabolic Equivalent of Task (MET) value in women treated for breast cancer.

DESIGN

Laboratory study.

METHODS

Fifty female patients shortly after completion of treatment for breast cancer were included. VO₂peak was determined during a cardiopulmonary exercise test. Subsequently, patients performed ten activities with different intensities while wearing an accelerometer on the right hip and a mobile oxycon to assess oxygen consumption. We studied the relationship between energy expenditure (expressed as %VO₂peak and MET-value) and accelerometer output (in counts per minute (cpm)) with linear regression analyses. We determined accelerometer output corresponding to physical activity intensity cut-points (40% and 60%VO₂peak; 3 and 6 MET) using regression equations.

RESULTS

VO₂peak was 22.4mL/kg/min (SD 5.2) and resting metabolic rate was 3.1mL/kg/min (SD 0.6). Accelerometer output corresponding to the cut-points for moderate (40% VO₂peak) and vigorous intensity (60% VO₂peak) were 1123 and 1911, respectively. The analyses based on MET-values resulted in accelerometer output of 1189cpm for the moderate (3 MET) and 2768 cpm for the vigorous intensity cut-point (6 MET).

CONCLUSIONS

Accelerometer outputs for moderate and vigorous intensity physical activity were lower than commonly used cut-points (i.e. 1952 and 5724 cpm), irrespective of the method used to express energy expenditure (%VO₂peak versus MET-value). Thus, categorizing physical activity intensities based on general-population cut-points, may underestimate physical activity intensities for women treated for breast cancer.