Exercise Prescription or Proscription in Colorectal Cancer
Men and women diagnosed with CRC (International Classification of Disease, Ninth Revision (ICD-9): 153 and 154) in the University of Pennsylvania Health System (UPHS) between October 30, 2008, and November 30, 2011, were considered for cohort inclusion. Cohort members were required to have all of their curative care in the UPHS. All cohort members were required to have a follow-up visit approximately 6 months after completing curative care. Patients with metastatic disease at diagnosis were excluded from cohort inclusion. This study was approved by the institutional review board of the University of Pennsylvania. The institutional review board determined that an informed consent could be waived on the basis that this study did not involve any direct patient interaction.
We conducted a targeted search to obtain peer-reviewed guidelines for exercise prescription among cancer survivors. Our search identified nine documents and ranged in publication year from 2006 to 2013. Three documents were published by the ACSM, including the ACSM's Guidelines for Exercise Testing and Prescription Eighth Edition, the ACSM's "Roundtable on Exercise Guidelines for Cancer Survivors", and the ACSM's Guide to Exercise and Cancer Survivorship. Additional documents were published by the ACS, NCCN, Australian Association for Exercise and Sport Science, and National Research Council Canada. Two documents were published by independent investigators, one as a supplement to the ACSM's "Roundtable on Exercise Guidelines for Cancer Survivors" and one that served as a foundation for the ACSM's guidelines. These guidelines were reviewed by the two authors, and health factors described as requiring referral to trained personnel for an individualized exercise program or supervision of exercise were abstracted into a categorized list. All guidelines were considered of equal importance, and health factors identified in any of the nine documents were included in this analysis. There was a high degree of consistency across guidelines, as 86% of health factors were described in two or more documents. Health factors were classified into one of the following system-specific categories: hematological, musculoskeletal, systemic, gastrointestinal, cardiovascular symptoms, cardiovascular disease history, pulmonary, neurological, comorbidities, and implanted medical device (see Table, Supplemental Digital Content 1, Derivation of outcomes, http://links.lww.com/MSS/A391). The presence of one or more health factors indicated the need to refer to trained personnel for an individualized exercise program or supervision of the ACSM/ACS/NCCN recommended dose of exercise. This approach is consistent with a variety of preexercise screening questionnaires.
The optimal time for lifestyle intervention and provision of lifestyle recommendations is 6 months after curative care. Six months allows time for the acute symptoms of cancer treatment to subside while still in the interval for the teachable moment to be in effect, a time when cancer survivors are most likely to adopt lifestyle and behavioral recommendations before regressing back to prediagnostic behaviors and lifestyle. Qualitative research has concluded that CRC survivors prefer to start exercise 6 months after completing curative care, when they feel physically and psychologically ready for exercise.
We abstracted data from the electronic medical record at the clinical visit most proximal to 6 months after curative care. Abstracted data included standard measures for cancer care follow-up in UPHS consisting of blood chemistry, resting pulse and blood pressure, oral temperature, physician-diagnosed symptoms and side effects, patient-reported symptoms and side effects present at the time of the clinical visit, and any ICD-9 or procedure codes used to classify conditions or procedures in our abstracted list. Demographic information, including age, sex, race, and tobacco use, were abstracted. Clinical information including type of cancer, stage (American Joint Committee on Cancer Staging Manual, Seventh Edition), and treatment (chemotherapy/radiation) were abstracted. We calculated the Charlson age comorbidity index to estimate 10-yr mortality.
Using the data abstracted at the 6-month follow-up visit, we generated binary variables (yes/no) to indicate if each cohort member had health factors sufficient to refer to trained personnel for an individualized exercise program or supervision of the ACSM/ACS/NCCN recommended dose of exercise. We generated a composite outcome as the sum of all health factors and then dichotomized that variable between CRC survivors that had zero versus one or more health factors. Values of zero indicate no need for referral or supervision of exercise. Values of one or more would indicate potential need to refer to trained personnel for an individualized exercise program or supervision of the ACSM/ACS/NCCN recommended dose of exercise. We estimated this proportion and calculated 95% confidence intervals (CI) using the binomial exact method. This outcome was modeled as our dependent variable in exploratory logistic regression analyses. We calculated the odds ratio (OR) and 95% CI to estimate the magnitude of association of demographic and clinical variables with the likelihood to refer to trained personnel for an individualized exercise program or supervision of exercise. For all covariates, we had ≥80% statistical power to detect an OR of 2.0, indicating a twofold increase in the need for referral for an individualized exercise program or supervised exercise. Lastly, we conducted prespecified sensitivity analyses, excluding common comorbidities among CRC survivors from the composite outcome including hypertension, diabetes, arthritis, obesity, and hyperlipidemia.
Methods
Cohort Inclusion
Men and women diagnosed with CRC (International Classification of Disease, Ninth Revision (ICD-9): 153 and 154) in the University of Pennsylvania Health System (UPHS) between October 30, 2008, and November 30, 2011, were considered for cohort inclusion. Cohort members were required to have all of their curative care in the UPHS. All cohort members were required to have a follow-up visit approximately 6 months after completing curative care. Patients with metastatic disease at diagnosis were excluded from cohort inclusion. This study was approved by the institutional review board of the University of Pennsylvania. The institutional review board determined that an informed consent could be waived on the basis that this study did not involve any direct patient interaction.
Synthesis of Exercise Guidelines
We conducted a targeted search to obtain peer-reviewed guidelines for exercise prescription among cancer survivors. Our search identified nine documents and ranged in publication year from 2006 to 2013. Three documents were published by the ACSM, including the ACSM's Guidelines for Exercise Testing and Prescription Eighth Edition, the ACSM's "Roundtable on Exercise Guidelines for Cancer Survivors", and the ACSM's Guide to Exercise and Cancer Survivorship. Additional documents were published by the ACS, NCCN, Australian Association for Exercise and Sport Science, and National Research Council Canada. Two documents were published by independent investigators, one as a supplement to the ACSM's "Roundtable on Exercise Guidelines for Cancer Survivors" and one that served as a foundation for the ACSM's guidelines. These guidelines were reviewed by the two authors, and health factors described as requiring referral to trained personnel for an individualized exercise program or supervision of exercise were abstracted into a categorized list. All guidelines were considered of equal importance, and health factors identified in any of the nine documents were included in this analysis. There was a high degree of consistency across guidelines, as 86% of health factors were described in two or more documents. Health factors were classified into one of the following system-specific categories: hematological, musculoskeletal, systemic, gastrointestinal, cardiovascular symptoms, cardiovascular disease history, pulmonary, neurological, comorbidities, and implanted medical device (see Table, Supplemental Digital Content 1, Derivation of outcomes, http://links.lww.com/MSS/A391). The presence of one or more health factors indicated the need to refer to trained personnel for an individualized exercise program or supervision of the ACSM/ACS/NCCN recommended dose of exercise. This approach is consistent with a variety of preexercise screening questionnaires.
Outcome Assessment Time Point
The optimal time for lifestyle intervention and provision of lifestyle recommendations is 6 months after curative care. Six months allows time for the acute symptoms of cancer treatment to subside while still in the interval for the teachable moment to be in effect, a time when cancer survivors are most likely to adopt lifestyle and behavioral recommendations before regressing back to prediagnostic behaviors and lifestyle. Qualitative research has concluded that CRC survivors prefer to start exercise 6 months after completing curative care, when they feel physically and psychologically ready for exercise.
Abstraction of Outcomes and Application of Exercise Guidelines to Participant Cohort
We abstracted data from the electronic medical record at the clinical visit most proximal to 6 months after curative care. Abstracted data included standard measures for cancer care follow-up in UPHS consisting of blood chemistry, resting pulse and blood pressure, oral temperature, physician-diagnosed symptoms and side effects, patient-reported symptoms and side effects present at the time of the clinical visit, and any ICD-9 or procedure codes used to classify conditions or procedures in our abstracted list. Demographic information, including age, sex, race, and tobacco use, were abstracted. Clinical information including type of cancer, stage (American Joint Committee on Cancer Staging Manual, Seventh Edition), and treatment (chemotherapy/radiation) were abstracted. We calculated the Charlson age comorbidity index to estimate 10-yr mortality.
Statistical Analysis
Using the data abstracted at the 6-month follow-up visit, we generated binary variables (yes/no) to indicate if each cohort member had health factors sufficient to refer to trained personnel for an individualized exercise program or supervision of the ACSM/ACS/NCCN recommended dose of exercise. We generated a composite outcome as the sum of all health factors and then dichotomized that variable between CRC survivors that had zero versus one or more health factors. Values of zero indicate no need for referral or supervision of exercise. Values of one or more would indicate potential need to refer to trained personnel for an individualized exercise program or supervision of the ACSM/ACS/NCCN recommended dose of exercise. We estimated this proportion and calculated 95% confidence intervals (CI) using the binomial exact method. This outcome was modeled as our dependent variable in exploratory logistic regression analyses. We calculated the odds ratio (OR) and 95% CI to estimate the magnitude of association of demographic and clinical variables with the likelihood to refer to trained personnel for an individualized exercise program or supervision of exercise. For all covariates, we had ≥80% statistical power to detect an OR of 2.0, indicating a twofold increase in the need for referral for an individualized exercise program or supervised exercise. Lastly, we conducted prespecified sensitivity analyses, excluding common comorbidities among CRC survivors from the composite outcome including hypertension, diabetes, arthritis, obesity, and hyperlipidemia.
Source...