Processes of behavior change and weight loss in a theory-based weight loss intervention program: a test of the process model for lifestyle behavior change (original) (raw)

Examining the psychological pathways to behavior change in a group-based lifestyle program to prevent type 2 diabetes

2012

OBJECTIVEdTo examine the psychological process of lifestyle change among adults at risk for type 2 diabetes. RESEARCH DESIGN AND METHODSdA randomized control trial in which 307 volunteers (intervention, n = 208; wait control, n = 99) diagnosed with prediabetes completed a sixsession group-based intervention to promote healthier living. Participants' motivation to change, diet and exercise self-efficacy, mood, knowledge about diabetes, activity levels, healthy eating, waist circumference, and weight were assessed before and after the program. RESULTSdParticipation in the program was associated with significant increases in healthy eating and physical activity, reductions in waist and weight, and improvements in motivation, positive mood, self-efficacy, and knowledge. Examination of the pathways to lifestyle change showed that the educational aspect of the program increased activity levels because it increased diabetes knowledge and improved mood. Eating behavior was not mediated by any of the psychological variables. Improvements in diet and physical activity were, in turn, directly associated with changes in weight and waist circumference. CONCLUSIONSdAlthough the program significantly improved motivation, self-efficacy, and mood, its impact on knowledge uniquely explained the increase in physical activity. Group-based programs that are tailored to lifestyle behaviors may provide a cost-effective method of diabetes prevention, but more research is needed to explain why they improve healthy eating.

Which Behavior Change Techniques are Associated with Changes in Physical Activity, Diet and Body Mass Index in People with Recently Diagnosed Diabetes?

Annals of Behavioral Medicine

Meta-analyses have identified promising behavior change techniques (BCTs) in changing obesity-related behaviors from intervention descriptions. However, it is unclear whether these BCTs are used by intervention participants and are related to outcomes. The purpose of this study is to investigate BCT use by participants of an intervention targeting physical activity and diet and whether BCT use was related to behavior change and weight loss. Intervention participants (N = 239; 40-69 years) with recently diagnosed type 2 diabetes in the ADDITION-Plus trial received a theory-based intervention which taught them a range of BCTs. BCT usage was reported at 1 year. Thirty-six percent of the participants reported using all 16 intervention BCTs. Use of a higher number of BCTs and specific BCTs (e.g., goal setting) were associated with a reduction in body mass index (BMI). BCT use was associated with weight loss. Future research should identify strategies to promote BCT use in daily life. (Tr...

An innovative program for changing health behaviours

Asia Pacific Journal of Clinical Nutrition

Health-related behaviours affecting diet, weight control and physical activity are important for long-term cardiovascular health but behaviour change is difficult to initiate and even more difficult to maintain. We have developed a health promotion program, in which social support has a key role, to encourage a prudent diet, weight control and physical activity. Behaviour change is based on evaluating initial behaviour, weighing up costs and benefits, assessing barriers to change and goal-setting. We first evaluated the program in couples beginning to live together, a group chosen because of the risk of weight gain and decreased physical activity after marriage, readiness to change behaviour at that time in the life course and the opportunity to use partner's support in achieving behaviour change. In an initial short-term study with 39 couples, intake of fat and takeaway foods decreased and consumption of fruit, vegetables and reduced fat foods increased. Physical activity increased and there was a 6% fall in blood cholesterol. Further evaluation in 137 couples included assessment after 12 months. A decrease in fat intake and increase in physical activity and fitness seen at the end of the program persisted 1 year later. Lower cholesterol and a trend to lower weight gain and lower blood pressure were also maintained after 12 months. We have modified the program aiming for weight loss, improved dietary habits and increased physical activity in overweight treated hypertensives, supported by their partners. Decreased intake of energy, total and saturated fat, and weight loss seen at the end of the 16 week program was significantly greater in the intervention group than with usual care. Blood pressure fell in the program group at the end of intervention and, in men, withdrawal of antihypertensive drugs was significantly associated with the intervention. Weight loss and a decrease in waist circumference were maintained in the program group up to 16 months after entering the study. This program has the potential for wider application in other at-risk groups.

Translating the Diabetes Prevention Program Lifestyle Intervention for Weight Loss Into Primary Care

JAMA Internal Medicine, 2013

Background: The Diabetes Prevention Program (DPP) lifestyle intervention reduced the incidence of type 2 diabetes mellitus (DM) among high-risk adults by 58%, with weight loss as the dominant predictor. However, it has not been adequately translated into primary care. Methods: We evaluated 2 adapted DPP lifestyle interventions among overweight or obese adults who were recruited from 1 primary care clinic and had pre-DM and/or metabolic syndrome. Participants were randomized to (1) a coach-led group intervention (n = 79), (2) a selfdirected DVD intervention (n = 81), or (3) usual care (n=81). During a 3-month intensive intervention phase, the DPP-based behavioral weight-loss curriculum was delivered by lifestyle coach-led small groups or homebased DVD. During the maintenance phase, participants in both interventions received lifestyle change coaching and support remotely-through secure email within an electronic health record system and the American Heart Association Heart360 website for weight and physical activity goal setting and self-monitoring. The primary outcome was change in body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) from baseline to 15 months. Results: At baseline, participants had a mean (SD) age of 52.9 (10.6) years and a mean BMI of 32.0 (5.4); 47% were female; 78%, non-Hispanic white; and 17%, Asian/ Pacific Islander. At month 15, the meanϮSE change in BMI from baseline was Ϫ2.2Ϯ0.3 in the coach-led group vs Ϫ0.9 Ϯ 0.3 in the usual care group (P Ͻ .001) and Ϫ1.6Ϯ0.3 in the self-directed group vs usual care (P=.02). The percentages of participants who achieved the 7% DPPbased weight-loss goal were 37.0% (P=.003) and 35.9% (P=.004) in the coach-led and self-directed groups, respectively, vs 14.4% in the usual care group. Both interventions also achieved greater net improvements in waist circumference and fasting plasma glucose level. Conclusion: Proven effective in a primary care setting, the 2 DPP-based lifestyle interventions are readily scalable and exportable with potential for substantial clinical and public health impact.

A Structured Intentions and Action-Planning Intervention Improves Weight Loss Outcomes in a Group Weight Loss Program

American Journal of Health Promotion, 2013

Purpose. To assess whether forming general behavioral intentions and implementing intentions through action plans promotes weight loss and is moderated by weight loss goals and self-efficacy. Design. A quasi-experimental study comparing change in body mass index (BMI) for 15 months between a behavioral intentions condition (BIC), an implementation intentions condition (IIC), and a comparison condition (CC). Setting. Ten-week weight loss program delivered in weekly group meetings at community medical centers. Subjects. Six hundred thirty-two attendants at the weight loss program (80% of program attendants participated in the study). Intervention. Weight loss program focused on lifestyle changes, augmented by two experimental conditions (vs. a comparison condition): BIC, intended use of weight loss techniques; IIC, intended use and detailed plans for two techniques. Phone follow-up was conducted 3 and 12 months later. Measures. Main outcome: BMI during the program (computed on the bas...

Changes in eating, physical activity and related behaviors in a primary care-based weight loss intervention

2013

Objective-To examine changes in eating behaviors and physical activity, as well as predictors of weight loss success, in obese adults who participated in a 2-year behavioral weight loss intervention conducted in a primary care setting. Design-A longitudinal, randomized-controlled, multi-site trial. Subjects-390 obese (body mass index, 30 to 50 kg/m 2) adults, ≥21 yr, in the Philadelphia region. Methods-Participants were assigned to one of three interventions 1) Usual Care [Quarterly primary care provider (PCP) visits that included education on diet and exercise]; 2) Brief Lifestyle Counseling [quarterly PCP visits plus monthly Lifestyle Counseling (LC) sessions about behavioral weight control]; or 3) Enhanced Brief LC (the previous intervention with a choice of meal replacements or weight loss medication). Results-At month 24, participants in both Brief LC and Enhanced Brief LC reported significantly greater improvements in mean (±SE) dietary restraint than those in Usual Care (4.4±0.5, 4.8±0.5, and 2.8±0.5, respectively; both ps≤0.016). The percentage of calories from fat, along with fruit and vegetable consumption, did not differ significantly among the three groups.

Two-year weight-loss maintenance in primary care-based Diabetes Prevention Program lifestyle interventions

Nutrition & Diabetes, 2013

OBJECTIVE: To investigate whether the effects on weight loss and cardiometabolic risk factor reduction of two technologymediated lifestyle interventions for 15 months in a primary care-based translation trial sustained at 24 months (that is, 9 months after the end of intervention). DESIGN: This study analyzed data from an extended follow-up of participants in the original 'E-LITE' (Evaluation of Lifestyle Interventions to Treat Elevated Cardiometabolic Risk in Primary Care)-randomized controlled trial, which demonstrated the effectiveness of two adapted Diabetes Prevention Program (DPP) lifestyle interventions compared with usual primary care. SUBJECTS: ELITE randomized 241 overweight or obese participants with pre-diabetes and/or metabolic syndrome to receive usual care alone (n ¼ 81) or usual care plus a coach-led (n ¼ 79) or self-directed intervention (n ¼ 81). The interventions provided coach-led group behavioral weight-loss treatment or a take-home, self-directed DVD using the same 12-week curriculum, followed by 12 additional months of technology-mediated coach contact and self-monitoring support. Participants received no further intervention after month 15. A blinded assessor conducted 24-month visits by following the measurement protocols of the original trial. Measurements include weight and cardiometabolic risk factors (waist circumference, fasting plasma glucose, resting blood pressure, triglycerides, high-and low-density lipoprotein cholesterol, total cholesterol and triglyceride to high-density lipoprotein cholesterol ratio). RESULTS: At month 24, mean ± s.e. changes in body mass index (trial primary outcome) and weight (kg) from baseline were-1.9 ± 0.3 (P ¼ 0.001) and-5.4 ± 0.9 (Po0.001) in the coach-led intervention, and-1.6 ± 0.3 (P ¼ 0.03) and-4.5 ± 0.9 (P ¼ 0.001) in the self-directed intervention, compared with-0.9±0.3 and 2.4±0.9 in the usual care group. In addition, both interventions led to a greater percentage of participants maintaining X7% weight loss and sustained improvements in waist circumference and fasting plasma glucose levels than usual care. CONCLUSION: This study shows sustained benefits of the two primary care-based, technology-mediated DPP lifestyle interventions. The findings warrant replication in long-term studies involving diverse populations.

Physical activity, diet, and weight loss in patients recruited from primary care settings: An update on obesity management interventions

Obesity Science & Practice, 2021

Background: Obesity and related comorbidities are the most common chronic conditions in North America where behavior modification including the adoption of physical activity (PA) and a healthful diet are primary treatment strategies. Patients are more likely to engage in behavior modification if encouraged by their physician; however, behavioral counseling in primary care rarely occurs due to lack of training and resources. A more effective method may be to refer patients from clinical settings to other health professionals. Objective: This systematic review examines the effectiveness of behavior-based counseling for obesity management among participants referred from clinical settings. Methods: PubMed, CINAHL, and EMBASE were used to identify randomized clinical trials (2014-2020) for weight loss with the following inclusion criteria: trial duration ≥12 months, included a control or usual care group, recruited adults with overweight or obesity from primary care and/or treated in the primary care setting, and the intervention included counseling on PA and diet. Results: Seventeen studies, encompassing 21 different intervention groups with 6185 unique participants (56% female) met the inclusion criteria. All participants had overweight or obesity, with a body mass index between 28.2 and 41.0 kg/m 2. In 11 (52%) of the intervention groups, significant weight loss in the intervention group was observed compared to usual care (mean weight loss: 4.9[2.1] kg vs. 1.0 [0.9] kg). In 13 out of 18 interventions (72%) reporting weight loss at two time points, weight regain was observed by 12 months. Statistically significant weight loss was observed in one intervention (of two total) that was longer than 12 months. Conclusions: Sustained weight loss regardless of the behavior-based, intervention strategy remains a challenge for most adults. Given the established benefits of routine PA and a healthful diet, prioritizing the adoption of healthy behaviors regardless of weight loss may be a more effective strategy for ensuring long-term health benefit.