and Paper-Based Weight Loss Programs Tailored for ... - Springer Link

5 downloads 33583 Views 289KB Size Report
Nov 6, 2012 - SHED-IT Resources program, the SHED-IT Online pro- gram (both programs 3 ... assistant who was not involved in enrollment, assessment, or allocation of .... and/or had the greatest scope for improvement. (c) Wait-list control ... adaptation of the Australian Government Department of Vet- eran Affairs ...
ann. behav. med. (2013) 45:139–152 DOI 10.1007/s12160-012-9424-z

ORIGINAL ARTICLE

The SHED-IT Community Trial: A Randomized Controlled Trial of Internet- and Paper-Based Weight Loss Programs Tailored for Overweight and Obese Men Philip J. Morgan, Ph.D. & Robin Callister, Ph.D. & Clare E. Collins, Ph.D & Ronald C. Plotnikoff, Ph.D & Myles D. Young, B.Psych & Nina Berry, Ph.D. & Patrick McElduff, Ph.D. & Tracy Burrows, Ph.D. & Elroy Aguiar, B.Biomed.Sc. & Kristen L. Saunders, B.App.Sci.

Published online: 6 November 2012 # The Society of Behavioral Medicine 2012

Abstract Background There is limited evidence for effective obesity treatment programs that engage men. Purpose This study evaluated the efficacy of two gendertailored weight loss interventions for men, which required no face-to-face contact. Methods This was a three-arm, randomized controlled trial: (1) Resources (n054), gender-tailored weight loss materials (DVD, handbooks, pedometer, tape measure); (2) Online (n 053), Resources materials plus study website and efeedback; and (3) Wait-list control (n052). The interventions lasted 3 months and were grounded in Social Cognitive Theory. Results At 6 months, significantly greater weight loss was observed for the Online (−4.7 kg; 95 % CI −6.1, −3.2) and

Resources (−3.7 kg; 95 % CI −4.9, −2.5) groups compared to the control (−0.5 kg; 95 % CI −1.4, 0.4). Additionally, both intervention groups significantly improved body mass index, percent body fat, waist circumference, blood pressure, physical activity, quality of life, alcohol risk, and portion size, compared to controls. Conclusions Men achieved significant weight loss after receiving novel, minimal-contact, gender-tailored programs, which were designed for widespread dissemination.

P. J. Morgan (*) : R. C. Plotnikoff : M. D. Young : N. Berry : K. L. Saunders School of Education, Priority Research Centre in Physical Activity and Nutrition, University of Newcastle, Callaghan, NSW 2308, Australia e-mail: [email protected]

Internationally, obesity in men is a significant public health concern [1]. The burden of disease associated with obesity falls disproportionately upon men, as overweight men have greater abdominal fat tissue compared with women, which increases their risk of cardiovascular disease [2]. In Australia, 68 % of men are overweight or obese compared with 55 % of women [3]. Further, over the last 30 years the average body mass index (BMI) of Australasian men has increased faster than for men in almost all other high-income countries [1]. Based on participation rates in weight loss randomized controlled trials (RCTs), weight loss programs have not appealed to men. For example, a recent systematic review of 244 lifestyle weight loss RCTs identified that only 27 % of participants were men [4]. The reasons for this lack of engagement are likely due to a lack of attention to gender differences in program design and a failure to consider the physiological, psychological, and socio-cultural gender

R. Callister : E. Aguiar School of Biomedical Sciences and Pharmacy, Priority Research Centre in Physical Activity and Nutrition, University of Newcastle, Callaghan, NSW 2308, Australia C. E. Collins : T. Burrows School of Health Sciences, Priority Research Centre in Physical Activity and Nutrition, University of Newcastle, Callaghan, NSW 2308, Australia P. McElduff School of Medicine and Public Health, University of Newcastle, Callaghan, NSW 2308, Australia

Keywords Weight loss . Men . Obesity . Online . Treatment

Introduction

140

differences that influence health behavior [5]. Clearly, many weight loss programs do not engage men or embed motivators relevant to men and may contain dietary restrictions that men consider unacceptable [6]. Men express preferences for convenient weight loss programs that promote incremental diet and lifestyle changes, provide individualized feedback, and, importantly, include other men [6–8]. However, the evidence in support of male-only weight loss interventions is limited in both quality and quantity [9]. This indicates that designing weight loss interventions that can both engage men and improve their health outcomes is a unique challenge. In general, men are not attracted to structured face-to-face programs [6–8, 10]. In a recent systematic review, Pagato and colleagues [4] found that group weight loss interventions had the lowest representation of men, whereas self-guided interventions (for example, e-mail and internet) had the highest representation. Therefore, alternative modes of delivery using online tools and/or interactive resources may be more appealing, accessible, and convenient for men. The SHED-IT pilot study demonstrated that a weight loss program tailored for men (either paper-based or Internet-based with support via email) facilitated weight loss in a sample of male university staff and students [11–14]; however, both programs included one face-to-face information session delivered by a member of the research team. To increase the generalizability of the interventions, the SHED-IT programs needed to be tested in a broader community sample. To determine the efficacy of the programs, they also needed to be compared to a nointervention control group. To improve the potential reach of the program, it was of interest to determine whether a DVD could replace the face-to-face information session; removing this component would provide evidence for a version of the program with far greater potential for uptake and widespread dissemination. The aim of the current study was to determine whether, in the absence of face-to-face contact, a weight loss program tailored for men could lead to significant weight loss and improvements in secondary health outcomes in a community sample of overweight and obese men. Given the large numbers of men in Australia who require support for weight loss, this study focused specifically on examining the efficacy of two programs that differed in mode of delivery [Internet-based (Online) versus paper-based (Resources)] and support [dietary feedback (Online) versus no dietary feedback (Resources)], but had the potential for dissemination on a large scale. It was hypothesized that: 1. Compared to controls, both the SHED-IT Online and Resources groups would achieve a statistically significant (a) reduction in weight and (b) improvement in secondary health outcome measures at 3 and 6 months post-baseline.

ann. behav. med. (2013) 45:139–152

2. The Online group would have greater improvements in weight loss and secondary health outcomes at 3 and 6 months post-baseline compared to the Resources group.

Methods Participants The SHED-IT community trial protocol has been described in detail elsewhere [15]. Briefly, 159 overweight and obese men (BMI between 25 and 40 kg/m2) from the Hunter Region of New South Wales, Australia, were recruited via media articles and workplace notices in August 2010. Men were screened for eligibility [15] and completed a preexercise risk assessment screening questionnaire [16]. Men with significant risk factors for exercise-related complications were required to present a doctor’s clearance to participate in the study. Ineligibility criteria included a history of major medical problems such as heart disease in the preceding 5 years, diabetes and orthopedic or joint problems that would be a barrier to walking, recent weight loss of 5 % or more, and taking medications that might affect body weight. All participants were required to refrain from participating in other weight loss programs during the study, and needed to have access to a mobile phone and a computer with email and Internet facilities. Institutional review and approval were provided by the Human Research Ethics Committee of the University of Newcastle, with written informed consent obtained from all participants prior to commencement. The trial was registered with the Australian New Zealand Clinical Trials Registry, Number ACTRN 12610000699066. Study Design This was a multi-arm parallel, assessor-blinded, randomized controlled trial. Men were stratified by BMI (25–29.9 kg/ m2; 30–34.9 kg/m2; 35–40 kg/m2) and randomized with a balanced ratio (1:1:1) to one of the three study arms: the SHED-IT Resources program, the SHED-IT Online program (both programs 3 months duration), or no intervention for 6 months (wait-list control). Sample Size The sample size calculation was based on the primary outcome of weight loss at 6 months (study’s primary time point), which was assumed to have a standard deviation of 5 kg [13, 17]. A sample of 150 men was needed to allow for an attrition rate of 28 % to give the study 80 % power to detect a difference in weight loss between groups of 4 kg at

ann. behav. med. (2013) 45:139–152

the 1.5 % significance level using a two-sided test. For the purpose of the sample size calculation, an alpha of 0.015 was used to control the type I error rate for multiple comparisons. Randomization and Allocation The trial statistician, who was not involved in assessments, generated the allocation sequence for randomization, stratified by baseline BMI category (overweight, obese I, obese II) with a 1:1:1 ratio in block lengths of six. Study information for the three different groups was pre-packed into identical black plastic opaque envelopes and ordered according to the randomization schedule. This was completed by a research assistant who was not involved in enrollment, assessment, or allocation of participants. After completing baseline assessments, participants moved to a separate room to meet with a research assistant who was not involved in the assessments. The allocation sequence was concealed during this process. Each participant was allocated the next available number in their BMI category before being provided with their information pack. The allocation sequence was only revealed to staff involved in assigning participants to intervention groups immediately prior to assignment. Allocation was concealed from assessors at all time points. Intervention The SHED-IT Online and SHED-IT Resources interventions both lasted 3 months. With the exception of the assessment sessions, neither intervention included any face-to-face contact. Both SHED-IT programs were theoretically based and operationalized Bandura’s Social Cognitive Theory [18], targeting key mediators such as self-efficacy, self-management, perceived barriers, and social support. (a) SHED-IT (Self-Help, Exercise and Diet) Resources Men were provided with a weight loss resource package, which included (1) the 25-min SHED-IT Weight Loss DVD for Blokes; (2) the Weight Loss Handbook for Blokes and the Weight Loss Support Book for Blokes; and (3) a pedometer, tape measure for waist circumference, and a kilojoule counter book. These resources promoted nine evidence-based, theorydriven weight loss messages: (1) Read food labels, (2) Keep a healthy lifestyle diary, (3) Reduce kilojoule-dense snacks, (4) Be prepared, (5) Every step counts, (6) Reduce sitting time, (7) Surf the urge (i.e., resisting the desire or “urge” to snack unnecessarily on kilojoule-dense foods in response to habit or stimuli other than true hunger), (8) Reduce your portion sizes, and (9) Do not drink your kilojoules. The resources were tailored for men using information from the pilot study process evaluation [8, 14] and the men’s

141

health literature [5, 19–21]. Aside from recruiting men only, the program ensured the messages delivered were meaningful to men. For example, the DVD and handbooks used humor to convey messages, as research in health communication shows this is valued by men [22] and is considered a central facet of masculinity [23]. For example, the DVD presented the weight loss messages through a series of common eating and exercise scenarios, where a male presenter (PJM) spent a “day in the life” with another male who was chosen to be representative of the study demographic. Interaction between the men about the challenges of eating healthily and being active each day was presented using a “light hearted” approach. Rather than a strict dietary regime, men were taught the mathematics of weight loss and were advised to achieve a negative energy balance of 2000 kJ per day. Men were encouraged to target several key dietary behaviours (i.e. reducing portion sizes, reducing consumption of energy-dense nutrient-poor foods and sweetened beverages, and increasing vegetable intake) as our formative work identified these to be particularly problematic areas for men. [11, 13]. Men were still able to consume some energy-dense foods and drinks such as alcohol on occasion. Importantly, these dietary strategies took into account the many psychological, physiological, and sociological gender-specific differences in eating behavior. For example, men’s approach towards nutrition tends to be uncomplicated and pleasure orientated whereas restrained eating, dieting, and eating disorders are much more common in women, emanating from the greater desire of women to control their body weight than men [20]. In order to make messages more meaningful for men, dietary and exercise information was “masculinized” using anecdotes and strategies that men could relate to. Other examples include outlining statistics and research based on men-only, using images of men, and listing examples of goals and social support strategies that were more likely to resonate with men (e.g. increasing steps on the golf course, incorporating “having a beer” into their lifestyle). Jokes using popular movies and male actors were also integrated (e.g., Star Wars, Indiana Jones, and James Bond). The Handbook included information regarding the mathematics of weight loss and explained the nine weight loss tips in detail. The Support book was used by men to set goals and to document their key behaviors and outcomes. In the support booklet, men were instructed to measure and record their weight and waist circumference on graphs once each week, to complete eating and exercise diaries 4 days each week (including two weekend days), to record their pedometer-based steps for four days each week, and to identify sources of social support and record two strategies each month. Men were asked to set three SMART goals each month (one each for weight, physical activity, and

142

eating). SMART goal examples were provided to help men understand how to write goals. A check box was included for men to tick off whether the goals were achieved and men were also instructed to identify “rewards” for achievement of all of the monthly goals. This booklet was collected at the end of the program. (b) SHED-IT (Self-Help, Exercise and Diet using Internet Technology) Online group In addition to receiving all of the materials from the SHED-IT Resources intervention, men randomized to the SHED-IT Online group were provided with a website user guide (developed by the research team) and were instructed to use the online food and exercise diary on the freely available commercial ‘CalorieKing™ (Australia) website (http://www.calorieking.com.au). The SHED-IT Weight Loss Handbook for Blokes and the SHED-IT Weight Loss Support Book for Blokes were modified slightly with instructions to use the online food and exercise diary for 4 days each week (including two weekdays and two weekend days) in place of the paper-based food and exercise diary used by the Resources group. Participants were also asked to “weigh-in”, i.e., record their weight on the website at least once a week. As in the SHED-IT Resources intervention, men were advised to use their Support Book to document all other key self-monitoring behaviors, social support strategies, and individual goals. Men in the Online group also received seven feedback emails about their food and exercise diary entries. Men provided signed consent for the researchers to access their website diaries, and were instructed to use a specified username and password. Over the course of the three months, each participant was emailed seven individualized feedback sheets by research assistants. Online diaries were reviewed weekly in the first month, fortnightly in the second month, and once in the third month. The feedback sheets used a standardised template with sections on weight loss outcomes and strategies to improve both dietary and exercise behaviours. The feedback was designed to provide general encouragement and specific strategies to address those aspects of the diary entries that were furthest from ideal and/or had the greatest scope for improvement. (c) Wait-list control Men received no program until after the 6-month assessments. Data Collection and Measures Measures were obtained from all men at baseline (September 2010), 3 months (immediate post-intervention, December 2010) and 6 months (3 month follow-up, March 2011). Participants from all study arms were sent a letter reminding

ann. behav. med. (2013) 45:139–152

them of the upcoming assessments and also an email with a link to an online booking site. Measurements were taken at the Human Performance Laboratory at the University of Newcastle by trained research assistants, who adhered to standardized procedures and were blinded to group allocation. Participants were blind to group allocation at the baseline assessment. Demographic Characteristics Socio-demographic variables were collected by questionnaire including age, marital status, occupation, gross annual family income, educational level, ethnic origin, language spoken at home, and socio-economic status (SES) [24]. Primary Outcome The primary outcome was body weight (kilograms), which was measured on a digital scale to 0.01 kg (CH-150kp; A&D Mercury Pty Ltd, Australia). Secondary Outcomes BMI was calculated as weight (kg)/height (m)2. Waist circumference was measured: (1) level with the umbilicus, and (2) at the largest circumference between the lower costal border and the umbilicus [25] with a non-extensible steel tape (KDSF10-02; KDS Corporation, Osaka, Japan). Body composition measures (body fat percent, visceral fat area, skeletal muscle mass) were assessed by bioimpedance using the multi-frequency InBody720 (Biospace Co. Ltd., Seoul, Korea), which has been shown to be valid and reliable [26]. Blood pressure and resting heart rate were measured using a NISSEI/DS-105E digital electronic blood pressure monitor (Nihon Seimitsu Sokki Co. Ltd., Gunma, Japan) under standardized procedures. Physical activity was objectively measured using Yamax SW-200 pedometers (Yamax Corporation, Kumamoto City, Japan) for seven consecutive days. These pedometers are both reliable [27] and valid [28]. Data were included if men wore them for at least 4 days. Sedentary behaviors were assessed using an adaptation of the Sitting Questionnaire, which has been shown to be both a valid and reliable measure of sitting time [29]. Dietary intake (i.e., total kilojoule intake) was assessed using the Australian Eating Survey. The Australian Eating Survey is a 135-item semi-quantitative food frequency questionnaire that has been used previously in Australian youth aged 9–16 years [30] and is currently being validated in adults. Men were asked to report the frequency of their consumption of items over the previous 6 months (at baseline) or 3 months (at follow-up assessments). Portion size was assessed using portion size photographs from the Dietary Questionnaire for Epidemiological Studies Version 2

ann. behav. med. (2013) 45:139–152

(DQES v2), Food Frequency Questionnaire from the Cancer Council Victoria [31]. These photos are used to calculate a single portion size factor (PSF) to indicate whether on average a person eats median size serves (PSF01), more than the median (PSF>1), or less than the median (PSF40) over the 3-month period and weekly weight records (n>10). That is, compliance was defined as self-monitoring eating and exercise diaries approximately 4 days a week and weekly weight recording. The extent of this self-monitoring was recommended in the interventions and was also based on optimal self-monitoring frequency established in the literature [39].

Results Participant Flow Figure 1 illustrates the flow of participants through the trial. Over 600 men responded to the recruitment materials within a week, with most participants responding to media stories. Screening ceased after 289 phone screens when 200 eligible men had been identified. One hundred and fifty-nine of the eligible men returned their consent forms in time to participate. Measurements were obtained from 82 % of the sample at 3 months and 81 % at 6 months, with no significant difference in follow-up rates between study arms at 3 months (χ2 00.958, df02, P00.619) or 6 months (χ2 00.809, df02, P00.667). All randomized participants with baseline data (n0159) were analyzed for the primary outcome at 3 and 6 months. Participants lost to 6-month follow-up had a lower mean sleepiness score (P00.01) and greater mean percent fat mass (P00.003) at baseline than those retained at 6 months. Baseline Data Table 1 shows men had similar demographic and other baseline characteristics across the three groups. The mean (SD) age of participants was 47.5 (11.0) years. The majority (91 %) were Australian born, 27 % were classified as overweight, and the remaining 73 % were obese. The mean weight and waist circumference at umbilicus of men were 103.4 kg (14.0) and 113.3 cm (9.5), respectively. Change in Weight Figure 2 illustrates the mean change in weight by treatment group from the intention-to-treat analysis, which revealed that both intervention groups lost a significant amount of weight at 6-month follow-up (P