Adherence to American Cancer Society Guidelines on Nutrition and Physical Activity in Female Cancer Survivors: Results from a Randomized Controlled Trial (Yale Fitness Intervention Trial)

Abstract

Background

American Cancer Society (ACS) publishes guidelines on nutrition and physical activity to minimize health risks in cancer patients and survivors. Studies show high adherence to such guidelines is associated with decrease in overall cancer incidence and mortality. However, there are sparse data on adherence to the ACS guidelines in cancer survivors.

Objective

The aim of this study was to describe adherence to the ACS guidelines in female cancer survivors who participated in an exercise intervention trial for 1 year.

Interventions/Methods

Peri-menopausal and early postmenopausal female cancer survivors (n=154) participated in a randomized controlled trial that examined the efficacy of an aerobic-resistance exercise intervention. In addition to BMI and alcohol, diet and physical activity data were collected with four day diet records and the International Physical Activity Questionnaire. A scoring system was used to determine adherence to the ACS guidelines, with scores ranging from 0 (no adherence) to 8 (highest adherence).

Results

Mean total adherence scores for ACS guidelines for all intervention and control condition participants, most of whom had breast or gynecological cancers, was 4.2 (baseline), 4.9 (6 months), and 4.8 (12 months), suggesting moderate adherence. Physical activity levels improved in both groups, however, no significant change was observed for adherence to weight, dietary or alcohol intake guidelines for either group.

Conclusions

Findings indicate only partial adherence to the ACS guidelines, even for motivated cancer survivors participating in an exercise intervention study.

Implications for Practice

Further research is needed regarding strategies and interventions to improve adherence to ACS guidelines.

INTRODUCTION

To minimize health risks in cancer patients, the American Cancer Society (ACS) has published guidelines for cancer survivors based on the most recent evidence on diet and physical activity patterns and cancer risk.¹ Guidelines include (1) maintaining a healthy weight, (2) adopting a physically active lifestyle, (3) consuming a healthy diet, and (4) limiting alcohol consumption. In particular, obesity is related to an increased risk of cancers including breast cancer in postmenopausal women,² and it is associated with poorer overall survival and increased mortality.^3,4 A physically active lifestyle can reduce the risk of breast, endometrial, and colon cancers² and it is related to decreased risk of cancer recurrence and mortality in cancer survivors.^5,6 A healthy diet rich in fruits and vegetables has been shown to lower the risk of lung, esophageal, stomach, and colorectal cancers² and it is associated with decreased overall mortality.^7,8 Alcohol intake is an established cause of cancers of the mouth, pharynx, larynx, esophagus, and liver² and higher alcohol consumption in cancer survivors is positively associated with overall mortality.⁸

Although evidence indicates that diet and physical activity have a significant impact on cancer outcomes, and while cancer patients do recognize diet as a potential cause for cancer development and an important factor for long-term health, it is important to understand patients’ actual current level of adherence to these guidelines. Adherence to health promoting lifestyle guidelines can decrease overall cancer incidence and mortality as well as prevent other health comorbidities.

In this paper, we therefore perform a secondary analysis of data collected in the Fitness Intervention Trial (FIT) involving peri-menopausal and postmenopausal women who were diagnosed and treated for breast, gynecologic, and/or colorectal cancers or lymphoma. Hypotheses of the current study are as follows:

• Women who participated in the exercise intervention component of the FIT study would not only change their exercise behavior, but would also improve other health behaviors, such as diet.

• Participants’ exercise and diet behavior would improve over the course of the year-long study.

We first investigate adherence to the ACS Guidelines on Nutrition and Physical Activity of female cancer survivors at the start of the FIT study and then examine whether participation in the FIT study improved their adherence over time.

MATERIALS AND METHODS

All study procedures were approved by the Human Subjects Research Review Committee and informed consent was obtained from all individual participants included in the study.

Study Design

The FIT was a randomized controlled trial designed to examine outcomes (bone mass, body composition, metabolic risk factors and functional status) of a 12 month aerobic-resistance exercise intervention compared to a home based physical activity group in peri-menopausal and postmenopausal female cancer survivors. Details of the study design and bone mass results are reported in a previously published article.⁹ In this secondary data analysis paper, we report baseline and post-baseline differences between the two groups of women on diet, physical activity, and adherence to ACS guidelines.

Briefly, the intervention group in the FIT study participated 3 times per week in aerobic-resistance exercise at a fitness center that was supervised for the first 6 months and then unsupervised for the next 6 months. The exercise intervention was designed to promote endurance and cardiovascular fitness (walking on a treadmill at a target heart rate goal), functional ability (resistance training for strength and flexibility), osteogenic stimuli (weight loaded belt), ground reaction forces (jumping), and joint reaction forces (lunges, squats, lower body weight lifting). Participants’ heart rate was measured every 5 minutes using a Polar heart rate monitor (Polar CIC Inc., Port Washington, NY). Participants were also encouraged to engage in moderate intensity activity on most other days of the week according to national guidelines.

The home based health promotion group (control group) was provided with national guidelines for the general public, recommending moderate intensity activity on most days of the week. Examples of types of moderate intensity activities were included in the guidelines.

At the beginning of the study, both groups were given a booklet describing healthy eating guidelines as suggested by the ACS, the American Heart Association (AHA), and the American Diabetes Association (ADA).¹⁰ The healthy eating guidelines suggested eating a variety of foods; increasing fruit, vegetable, and whole grain intake; limiting fat (particularly saturated fat and high cholesterol) intake, consuming calories to maintain weight, and limiting alcohol consumption. To give an overview of the booklet’s contents, a nutritionist provided all participants with a summary of the material on healthy eating guidelines. Participants’ questions regarding food choices, amounts, and previous misconceptions on healthy eating were discussed and answered. Both groups received calcium (1200 mg) and vitamin D (400 IU) supplements.

Sample

Participants in the parent FIT study included women diagnosed with breast, gynecologic or colorectal cancers or lymphoma who (1) completed non-hormonal therapy ≤ 36 months ago in the peri-menopausal transition or in early postmenopause (< 60 months since the last menstrual period), (2) had normal bone mineral density or osteopenia (T score −1.0 to −2.5) at baseline assessment, (3) were physically able to participate in the exercise program (physician release), (4) were English speaking, and (5) were able to complete questionnaires and give informed consent.

Setting

The exercise program for the intervention group was provided at community fitness centers. Each participant was given membership to a fitness center, and the study exercise intervention was taught and supervised by trained research interventionists.

The control group participants received monthly telephone calls to monitor their physical activity level. They also received generic cancer survivor information that did not specifically include the exercise component of the intervention.

Data Collection

Diet Records

Four day diet records were used to collect dietary intake at baseline, and 6 and 12 months post-baseline. These records, one for each day, included sections for breakfast, lunch, dinner, snacks, medications, and supplemental vitamin and mineral intake. At the beginning of the study, participants were educated on how to complete the record. Participants wrote the names of foods and drinks and the amount of each consumed each day. They were taught to estimate food portion size using various common household measures, such as standard measuring cups and spoons. These four page records were mailed to participants for completion before their scheduled hospital visits and were collected at these visits. Trained research staff reviewed the contents with participants for completeness and accuracy. The 4 day diet records were analyzed using the Elizabeth Stewart Hands and Associates (ESHA) Food Processor nutrition analysis system (version 10.3).

International Physical Activity Questionnaire

The International Physical Activity Questionnaire (IPAQ) short version was used to assess the physical activity level of study participants. Developed to obtain internationally comparable measures of physical activity,¹¹ reliability and validity of IPAQ was examined in 12 countries. The Spearman correlation coefficient for reliability was approximately 0.8, which indicates very good repeatability. There was also fair to moderate agreement (Spearman correlation coefficient for criterion validity of 0.3) with objective physical activity data measured by Computer Science and Application’s Inc. accelerometers.¹² The IPAQ short version was collected at baseline and then monthly after randomization to intervention or control groups either by face-to-face or telephone interviews. Study participants were asked about vigorous, moderate, and walking activities in the previous 7 days (for each type of activity, number of days and average amount of time per day), as well as average time spent sitting on a week day.

Adherence Scoring of ACS Guidelines on Nutrition and Physical Activity

To assess and operationalize adherence to ACS guidelines, a scoring system developed by McCullough and colleagues^13,14 was adapted. The method assigns 0 to 2 points for each of the four guidelines (0 = not meeting the recommendation, 1 = partial compliance, and 2= full compliance), resulting in a total adherence score for the 4 components that ranged from 0 to 8.

First ACS Recommendation: Maintain a Healthy Weight

To operationalize maintaining a healthy weight, participants within a normal weight range (BMI < 25 kg/m²) received a score of 2 for maintaining a healthy weight, within an obese range (BMI ≥ 30 kg/m²) received a score of 0, and those with BMI > 25 kg/m² and BMI < 30 kg/m² (overweight) received a score of 1.

Second ACS Recommendation: Adopt a Physically Active Lifestyle

To operationalize adoption of a physically active lifestyle, physical activity collected with IPAQ was first converted to metabolic equivalent (MET)-minutes based on activity values from the Compendium of Physical Activities by the American College of Sports Medicine.¹⁵ METs are intensity units based on energy expenditure, with one MET defined as the energy expenditure for sitting quietly. Total physical activity MET-minutes/week was calculated according to the Guidelines for Data Processing and Analysis of the IPAQ. As can be seen in Table 1, each activity was scored by specific type and intensity. In particular, walking MET-minutes per week was calculated by multiplying average walking minutes per day and number of walking days and then multiplying this result by 3.3 to account for the energy expenditure used in walking relative to sitting. Similar calculations were used to determine moderate intensity and vigorous intensity MET-minutes per week, with multipliers of 4.0 and 8.0, respectively. The walking, moderate-intensity, and vigorous-intensity MET-minutes per week were then summed. Less than 600 MET-minutes/week received a score of 0 for adherence to the ACS guideline of adopting a physically active lifestyle, 600–1200 MET-minutes/week received a score of 1, and ≥ 1200 MET-minutes/week received a score of 2.

Table 1.

Calculation of MET-minutes/week measured by IPAQ

Type of activity	Calculation Formula
Walking MET-minutes/week	3.3 * average walking minutes/day * walking days
Moderate MET-minutes/week	4.0 * average moderate-intensity activity minutes/day * moderate days
Vigorous MET-minutes/week	8.0 * average vigorous-intensity activity minutes/day * vigorous-intensity days
Total physical activity MET-minutes/week	sum of Walking + Moderate + Vigorous MET-minutes/week scores

Abbreviations: IPAQ, International Physical Activity Questionnaire; MET, metabolic equivalent.

Third ACS Recommendation: Consume a Healthy Diet with Emphasis on Plant Foods

The ACS guideline for a healthy diet is comprised of three components: (1) eat at least 5 servings of fruits and vegetables each day, (2) consume whole grains instead of refined grain products, and (3) limit consumption of red and processed meats. Each component received a score, and an overall score for a healthy diet was then computed. Consumption of a healthy diet was operationalized by this overall score.

For the first component (eating at least 5 servings of fruits and vegetables each day), the number of servings was counted according to the Exchange List System for Diabetic Meal Planning.¹⁶ Vegetables such as French fries, prepared in an unhealthy manner, were not included in this count. Participants received 1 point if they consumed ≥ 5 fruit and vegetable servings/day. They received an additional 1 or 2 points for being in the 2nd or 3rd tertile, respectively, of total carotenoids consumed, a measure used to represent quality of fruit and vegetables.

For the second component (consuming whole grains instead of refined grain products), not many participants in the present study specified whether the cereals, breads, and pasta they consumed were whole grains or refined grain products. Therefore, fiber was used as a proxy for whole grains as it is its major constituent. Fiber intake was divided into quartiles and assigned scores of 0–3 (lowest quartile = 0).

For the third component (limiting consumption of red and processed meats), the number of servings each week was counted according to the Exchange List System for Diabetic Meal Planning. Included in the calculation were beef, pork, hamburgers, hot dogs, lunch meat, sausage, bacon, etc. Intake (servings/week) was divided into quartiles and assigned scores from 0 to 3 (lowest quartile = 3).

To calculate an overall score for consuming a healthy diet, the three component scores were summed (0– 9 points) and then divided into three groups: those whose sum totaled 0–2 were assigned a score of 0 for the overall score for consuming a healthy diet, those whose sum totaled 3–6 were assigned a score of 1 for consuming a healthy diet, and those whose sum totaled 7–9 were assigned a score of 2 for consuming a healthy diet.

Fourth ACS recommendation: Limit Alcohol Consumption

To operationalize limited alcohol consumption, a score of 0 was given to women who consumed more than 1 drink per day, with moderate drinkers (1 drink/day) receiving a score of 1, and nondrinkers receiving a score of 2.

Statistical Analyses

Means and standard deviations were used to describe the ACS guideline adherence scores. For the physical activity guideline, means and standard deviations were used to describe the types and intensity of activity and total MET-minutes/week. Baseline scores of MET-minutes/week between the 2 groups were compared using a t-test. To assess changes in physical activity over 1 year, a time-group interaction effect was examined using a generalized linear mixed model (GLMM) with a within subject correlation structure. The model tested the time effect in the exercise intervention and control groups and the difference in time effects between the 2 groups.

The adherence scores for each guideline ranged from 0 to 2 and were considered as ordinal variables. They were tested using a proportional odds model (POM) that provides a cumulative odds ratio for higher scores. The total ACS adherence score, which ranged from 0 to 8, was considered a continuous variable and tested using GLMM with an estimation of time-group interaction. Comparison of changes in the mean ACS scores over 1 year between the 2 groups was performed using a generalized estimating equation (GEE) analysis.

An alpha of 0.05 was used for level of statistical significance. All analyses were performed using SAS software, Version 9 of the SAS system for Windows.

RESULTS

Sample

Details of the recruitment process and sample characteristics are described in a previously published article.⁹ Briefly, of the 672 female cancer survivors screened, 308 were eligible, and 154 were enrolled in the study. Seventy six participants were randomly assigned to the exercise intervention group and 78 participants were randomly assigned to the control group. Of the 154 participants, 4 women left the study after baseline data collection, 11 women withdrew within the first 6 months, and 3 women had a recurrence of cancer and were excluded from the study (attrition rate of 11.6%). There were no differences in attrition between the study groups.

Mean age of participants was 57.9 years (±7.1 years). Participants were predominantly white (88.3%), married (70.1%) with children (78.6%), and had at least some college education (82.7%). Most worked full-time (66.9%) and nearly half (47%) identified their household income as ≥$100 000. The majority of participants had breast (83.1%) or gynecological cancer (11.8%). Two-thirds of participants had received radiation (62.7%), and nearly half had chemotherapy (52.6%). Adjuvant endocrine therapy was common in women with breast cancer. Women in the intervention group were younger (50.6 years) than women in the control group (53.1 years) (p= .01).

Adherence Score of the ACS Guidelines on Nutrition and Physical Activity

First ACS Recommendation: Maintain a Healthy Weight

Nearly two-thirds of participants were overweight or obese with a mean BMI of 29.0 (±6.8) at baseline, 29.3 (±6.6) at 6 months post-baseline, and 29.1 (±6.7) at 12 months post-baseline (Table 2). There was no difference in BMI between groups over the 12 month period (p= .26).

Table 2.

BMI over 1 year

	Exercise Intervention Mean (SD)			Health Promotion (Control) Mean (SD)
	Baseline (n=76)	6 months (n=66)	12 months (n=60)	Baseline (n=78)	6 months (n=72)	12 months (n=70)
BMI	29.5 (6.8)	30.2 (7.1)	30.0 (7.2)	28.5 (6.8)	28.5 (6.1)	28.3 (6.2)

Abbreviations: BMI, body mass index.

Second ACS Recommendation: Adopt a Physically Active Lifestyle

Total MET-minutes/week was 1387.8 (SD: ±1676.7, median: 800.0), 2088.3 (SD: ±2232.2, median: 1388.9), and 1483.8 (SD: ±1362.3, median: 1074.3) at baseline, and 6 and 12 months post-baseline, respectively.

Compared to baseline, total MET-minutes/week increased at 6 and 12 months post-baseline for the exercise intervention group, while there was a decrease for the control group. The changes between the groups were significantly different at 6 (p< .0001) and 12 months post-baseline (p= .04) (Table 3, Table 4). In both groups, moderate MET-minutes/week increased at 6 and 12 months post-baseline, but the increase was much larger in the exercise intervention group at 6 months post-baseline (p= .0004). The distinguishable differences between the groups were especially seen in vigorous and walking MET-minutes/week. In particular, vigorous and walking MET-minutes/week increased significantly for the exercise group compared to the control group at 6 (p< .0001) and 12 months post-baseline (p= .0066). Change in walking MET-minutes/week between the groups was significant only at 6 months post-baseline (p= .02).

Table 3.

MET-minutes/week at baseline

	Exercise Intervention	Health Promotion (Control)	p value
Total MET-minutes/week	1327.2 ± 1493.8	1446.0 ± 1843.3	0.07
Moderate MET-minutes/week	434.9 ± 682.4	488.3 ± 844.7	0.06
Vigorous MET-minutes/week	353.7 ± 485.9	313.0 ± 704.5	0.001
Walk MET-minutes/week	538.6 ± 720.2	644.6 ± 1034.5	0.002

Abbreviations: MET, metabolic equivalent.

Table 4.

MET-minutes/week over 1 year

	Time	Exercise Intervention	Health Promotion (Control)	p value
Total MET-minutes/week	6 month	1712.83 ± 258.16	−282.68 ± 250.72	<.0001
	12 month	587.14 ± 272.90	−161.95 ± 261.14	0.04
Moderate MET-minutes/week	6 month	681.23 ± 127.38	33.15 ± 123.87	0.0004
	12 month	115.69 ± 133.59	38.19 ± 128.25	0.67
Vigorous MET-minutes/week	6 month	797.69 ± 102.57	−137.03 ± 99.33	<.0001
	12 month	342.39 ± 110.23	−77.82 ± 104.78	0.0066
Walk MET-minutes/week	6 month	236.63 ± 127.78	−178.80 ± 124.52	0.02
	12 month	157.37 ± 132.40	−126.27 ± 127.75	0.12

Abbreviations: MET, metabolic equivalent.

Third ACS Recommendation: Consume a Healthy Diet with Emphasis on Plant Foods

The average daily servings of fruits and vegetables was 3.4 (±1.9) at baseline, and 3.6 (±2.1, 1.8) at 6 and 12 months post-baseline. Participants in the control group consumed significantly more fruits and vegetables (3.8 servings, ±2.1) than those in the exercise intervention group (3.0 servings, ±1.6) at baseline (p= .01). However, there were no differences in fruits and vegetables intake between the 2 groups over the 12 month period (p= .07) (Table 4). The mean fiber intake was 17.0 (g) (±8.0) at baseline and 18.1 (g) (±9.6) at 6 months and 17.3 (g) (±7.8) at 12 months post-baseline. There was no difference in fiber intake between the 2 groups over the 12 month period (p= .67). Mean servings of red meat for all participants was 0.8 for each data point and there was no difference between groups over the 12 month period (p= .91).

Fourth ACS recommendation: Limit Alcohol Consumption

Mean alcohol intake for all participants was 0.4 (±0.6) at baseline and 0.3 (±0.5) at 6 and 12 months post-baseline (Table 5). Alcohol intake decreased at 6 and 12 months post-baseline in the exercise intervention group while it stayed about the same in the control group (p= .03).

Table 5.

Average daily fruits and vegetables, red meat, and alcohol intake over 1 year

	Exercise Intervention Mean (SD)			Health Promotion (Control) Mean (SD)
Servings	Baseline (N=75)	6 month (N=63)	12 month (N=53)	Baseline (N=72)	6 month (N=65)	12 month (N=66)
Fruits and Vegetables	3.0 (1.6)	3.5 (1.9)	3.5 (1.7)	3.8 (2.1)	3.8 (2.3)	3.7 (1.9)
Red meat	0.8 (0.7)	0.7 (0.7)	0.7 (0.7)	0.8 (0.7)	0.9 (0.8)	0.8 (0.7)
Alcohol	0.4 (0.6)	0.3 (0.5)	0.2 (0.3)	0.4 (0.6)	0.4 (0.6)	0.3 (0.5)

Overall Adherence to the ACS Guidelines for Nutrition and Physical Activity

For the total adherence score, the findings suggest modest adherence. Out of a possible score of 8, the mean total score was 4.2 (±1.5) at baseline, 4.9 (±1.5) at 6 months post-baseline, and 4.8 (±1.6) at 12 months post-baseline (Table 6). Of the four lifestyle behaviors included in the total score, adherence to the alcohol guideline score was the highest at all 3 time periods. Mean BMI and diet scores were similar at all 3 time points. The mean physical activity score increased slightly at 6 months. There was a significant overall group by time difference (p= .0241) in the physical activity score. In the exercise intervention group, the mean score at 6 months post-baseline (5.03) was significantly higher than at baseline (4.07) (p< .0001), the mean score at 12 months post-baseline (4.74) was significantly higher than at baseline (p= .0004), but there was no difference between the scores at 6 and 12 months post-baseline (p= .08). In the control group, the mean score at 6 months post-baseline (4.69) was significantly higher than the mean score at baseline (4.38) (p= .04) but no significant difference was observed between baseline and 12 months post-baseline (p= .10) or between 6 and 12 months post-baseline (p= .93). For each component of the total score, only the physical activity score showed significant overall group by time difference (p= .0004).

Table 6.

Mean adherence scores for ACS Guidelines on Nutrition and Physical Activity

	Exercise Intervention Mean (SD)			Health Promotion (Control) Mean (SD)
	Baseline (n=74)	6 month (n=62)	12 month (n=49)	Baseline (n=72)	6 month (n=65)	12 month (n=62)
BMI Score	0.9 (0.8)	0.8 (0.8)	0.9 (0.8)	1.0 (0.9)	1.0 (0.9)	1.1 (0.9)
Physical Activity Score	0.9 (0.8)	1.8 (0.5)	1.3 (0.7)	0.9 (0.9)	1.2 (0.8)	1.2 (0.8)
Diet Score	0.9 (0.6)	1.0 (0.6)	0.9 (0.6)	0.9 (0.7)	1.0 (0.7)	1.0 (0.6)
Alcohol Score	1.4 (0.7)	1.4 (0.6)	1.7 (0.5)	1.5 (0.7)	1.4 (0.7)	1.5 (0.7)
Total Score	4.1 (1.4)	5.0 (1.3)	4.8 (1.4)	4.4 (1.6)	4.7 (1.6)	4.8 (1.8)

Abbreviations: ACS, American Cancer Society; BMI, body mass index.

^*BMI score: 0 : ≥ 30 kg/m², 1 : 25 to < 30 kg/m², 2 : < 25 kg/m²

^*Physical activity score: 0 : < 600 MET minutes/week, 1 : 600–1200 MET minutes/week, 2 : > 1200 MET minutes/week

^*Diet score determined from combined scores of fruit/vegetable, fiber, and red/processed meat intake: 0 : 0–2 combined score, 1 : 3–6 combined score, 2 : 7–9 combined score

^*Alcohol score: 0 : > 1 drink/day, 1 : > 0 to ≤1 drink/day, 2 : nondrinker

^*Total score = BMI Score + Physical Activity Score + Diet Score + Alcohol Score

Table 7 provides a breakdown of participants’ ACS adherence scores.

Table 7.

Proportion of participants with adherence scores over 1 year

Adherence Score	Exercise Intervention (%)			Health Promotion (Control) (%)
	Baseline	6 month	12 month	Baseline	6 month	12 month
0–2	16.2	3.2	4.1	11.1	9.2	11.3
3	13.5	6.5	18.4	19.4	10.8	8.1
4	31.1	22.6	20.4	22.2	27.7	25.8
5	24.3	38.7	24.5	20.8	24.6	25.8
6	10.8	14.5	22.4	18.1	13.9	8.1
7	4.1	11.3	8.2	5.6	7.7	11.3
8	0	3.2	2.0	2.8	6.1	9.6

DISCUSSION

In this randomized controlled trial of a 12 month aerobic-resistance exercise intervention in peri-menopausal and postmenopausal female cancer survivors, we examined the extent to which their health promoting lifestyle behaviors were consistent with the ACS Guidelines on Nutrition and Physical Activity. Although studies have reported that adherence to these guidelines was associated with a decrease in cancer mortality,¹⁷ not many studies have assessed such adherence in cancer survivors.

Adherence to ACS guidelines was modest in the current study as the average total score was 4.2, 4.9, and 4.8 out of 8 at baseline, 6 and 12 months, respectively. Importantly, adherence to the alcohol intake guideline contributed the most to the total score. The total score increased at 6 and 12 months in both the exercise intervention and control groups, but the increase was only minimal. Participants in the exercise intervention group showed the greatest increase at 6 months, but both groups had the same average adherence score at 12 months. For the physical activity guideline, about 40% of participants were not adherent to this guideline at baseline. However, at 6 and 12 months, about 80% of the participants showed partial or full compliance with the guidelines. For the diet guideline, 50%–60% of the participants showed partial compliance with the guidelines at baseline, but the percentage did not change over the 12 month period.

These results indicate that adhering to ACS guidelines is challenging in the group of cancer survivors who were given information about these guidelines at baseline. Some studies have suggested a potential role of physical activity as a gateway to induce changes in other health promoting lifestyle behaviors.^18,19 However, results from the current study show that changing exercise behavior, as was the case among FIT participants, does not necessarily lead to changes in other health promoting lifestyle behaviors. This gives support to the recognition that in order to change a particular behavior, an intervention designed specifically for that targeted behavior may be needed.

To the authors’ knowledge, this is the first study to examine adherence to the ACS guidelines in adult cancer survivors using quantified scores. Few studies have assessed dietary intake and physical activity behaviors using quantified ACS guidelines adherence scores. Only 2 prospective cohort studies with healthy individuals and one study with childhood cancer survivors were found.

McCullough et al. examined 50,727 men and 61,239 women in the Cancer Prevention Study II (CPS-II) Nutrition Cohort.¹³ Similar to the current study participants, those in CPS-II were largely white (97%), married (89%), highly educated (38% college graduates), and overweight (40%) or obese (15%), with a mean age of 61.9 years for women. Results of the ACS guidelines adherence scores were also similar to those in the current study. Only 4% of women met all the recommendations and scored 8. The proportion of women for each score was as follows: 0–2 (11.6%), 3 (15.6%), 4 (20.5%), 5 (22.0%), 6 (17.1%), 7, 8 (13.4%).

In the second prospective cohort study, Thomson and colleagues used the same ACS guidelines adherence scores for postmenopausal women in the Women’s Health Initiative Observational Study (WHI-OS) aged between 50 and 79.¹⁴ A similar pattern for each ACS adherence score was observed: 0 (0.4%), 1 (3.8%), 2 (12.2%), 3 (19.9%), 4 (22.9%), 5 (20.8%), 6 (13.7%), 7 (5.4%), and 8 (0.9%).

The ACS guidelines adherence scores were also used to assess 413 childhood cancer survivors who were diagnosed prior to age 21 and survived for more than 5 years after diagnosis compared to 361 controls.²⁰ Participants’ mean age was 28.4 and many were either overweight (28.9%) or obese (32.4%). Childhood cancer survivors had the highest scores for physical activity, with 60.5% of them meeting physical activity goals. They had a mean ACS adherence score of 4.3 (±1.5) but only 0.7% of them scored the maximum 8 points, 4.8% met the red meat recommendation, 17.7% consumed at least five servings of fruits and vegetables per day, and 10.2% adhered to fiber recommendation. Childhood cancer survivors had slightly higher ACS adherence scores (4.3 ± 1.5) compared to controls (4.2 ± 1.5), although the difference was not statistically significant.

Results of the current study showed similar findings to other studies performed in non-cancer populations and among childhood cancer survivors using the same scoring method. These findings suggest that being a cancer survivor does not yield changes in health behaviors to a substantial level.

Kohler and colleagues reported that high adherence to ACS and World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) guidelines was associated with a 10 – 61% decrease in overall cancer incidence and mortality. Notably, cancer survivors are at higher risk for secondary cancers due to their cancer treatments and prolonged survival. It is therefore critical that they adhere to guidelines in order to prevent these cancers and other health comorbidities. In fact, when adherence to WCRF/AICR guidelines was assessed in association with prevalence of metabolic syndrome in breast cancer survivors, meeting all recommendations was associated with a 57% lower prevalence of metabolic syndrome (95% CI, 0.35–0.73). However, results from this study and those of others suggest that cancer survivors’ level of adherence to guidelines is suboptimal. Knowing this, health care providers have an opportunity to help their cancer surviving patients to lessen their patients’ morbidity and mortality by emphasizing the importance of healthful behaviors as given in the guidelines, especially with regard to diet and exercise.

There are limitations to the study. Study participants consisted of 154 peri-menopausal or postmenopausal female cancer survivors who were generally highly educated, employed, and mid-life white women with cancer who lived in Connecticut. The study sample does not represent the diverse socio-demographic characteristics of female cancer survivors in the US. Therefore, generalizability of the study results is limited. Regarding diet data collection, recording four days of diet records might have been burdensome to participants because it requires a high level of participant literacy and cooperation. It has been suggested that the burden of keeping 4 day diet records may alter the number and types of foods and beverages consumed and participants may decrease the complexity of their diet so that it is simpler to record.²⁵ In addition, self-reported data might have involved social desirability. As with all questionnaires, responses on diet records were subject to participants’ diligence and validity of their self-report. However, research assistants reviewed diet records with participants at the point of data collection to ensure the greatest possible completeness and accuracy, and there was no evidence that the validity of their self-report was different between the 2 study groups.

IMPLICATIONS FOR PRACTICE

With increased screening and improved treatment modalities, cancer survivors are living longer and their cancer-specific mortality is decreasing while mortality from other health comorbidities is increasing.^24,26 Compared to non–cancer populations, some cancer survivors have a higher prevalence of comorbid conditions²⁴ and comorbidity level is an important factor in non-cancer mortality and overall survival in all cancer survivors.²⁶ Therefore, it is critical that cancer survivors prevent other comorbidities through changes in their lifestyle behaviors. Unfortunately, findings from the current study show only partial adherence to the ACS guidelines in cancer survivors participating in an exercise intervention study. To minimize risks for chronic conditions and to improve the general health of cancer survivors, it is important to assess adherence to health promoting lifestyle behavior guidelines and evaluate outcomes at the individual patient level.

Nurses and advanced practice nurses in oncology and primary care settings can play a critical role in educating cancer survivors on health promoting lifestyle behaviors. Studies report that health professionals are the most common sources of information among cancer patients (27.3%), and among health professionals, and nurses (28.2%) are one of the leading sources after physicians (43.7%).²⁷ However, more than 50% of cancer survivors have reported that their information needs on physical activity and diet were unmet²⁸ and only 20% of oncologists provided such guidance.²⁹ It is unclear how well nurses and advance practice nurses in oncology and primary care settings are aware of the ACS guidelines. In order to provide sufficient information for cancer survivors, it is critical that health care providers be well educated on the guidelines and methods to assess level of adherence.

In addition, there is often poor and delayed communication and lack of clarity regarding roles between primary care providers (PCPs) and cancer specialists.³⁰ The roles of PCPs and cancer specialists regarding patient education need to be clearly defined.

However, awareness of the ACS guidelines may not be sufficient to improve cancer survivors’ adherence. Close monitoring and repeated encouragement from health care providers are needed to enhance healthy lifestyle in these survivors.

IMPLICATIONS FOR FUTURE RESEARCH

Despite the initial education on ACS Guidelines on Nutrition and Physical Activity, few participants in the current study were highly adherent to the guidelines. Previous studies indicate that there is little difference in health behaviors between the general public and cancer survivors. Further research is needed to explore reasons why cancer survivors are not adherent to the ACS guidelines. Awareness of the existence of the guidelines, level of understanding of the guidelines, and patient and environment characteristics that affect implementation of the guidelines need to be examined. In-depth qualitative interviews would likely provide considerable insight regarding the extent to which cancer survivors adopt guidelines.

In addition, in order to educate cancer survivors on health promoting lifestyle behaviors, it is important that health care providers are well informed about the guidelines. Further research is needed to assess health care providers’ knowledge on the guidelines and methods to assess patients’ adherence levels.