Maximizing retention in long-term clinical trials of a weight loss agent: use of a dietitian support team.

OBJECTIVE: High-attrition rates have been observed in long-term clinical trials of weight loss agents. We evaluated the impact of an innovative retention programme on 1-year retention. METHODS: Three Phase 3 global multicentre clinical trials evaluated the efficacy and safety of a CB1 receptor antagonist in subjects with BMI ≥ or = 27 kg/m2. The impact of a multifaceted retention programme including a dietitian screening interview, a comprehensive culturally adapted lifestyle modification programme, and a dietitian support system to maximize lifestyle adherence, was evaluated in 4,410 subjects from four subpopulations (non-US English-speaking, non-English-speaking, US-without dietitian screening and US-with dietitian screening) comprising 208 centres from 15 countries. RESULTS: The median proportion retained over the first year among subjects in three protocols was 82%. Non-English-speaking countries showed higher retention rates (89%) compared with the USA (73%) and non-US English-speaking (81%) countries. Within the USA, behavioural screening was associated with 29% reduction in dropout rate; for every five monthly teleconferences attended above 11, there was a 32% decrease in dropout rate. CONCLUSIONS: This novel retention programme greatly improved upon reported retention rates of studies conducted with other weight loss agents in long-term clinical trials. Its effectiveness should be confirmed in future trials.

The effect of lifestyle intervention and metformin on preventing or delaying diabetes among women with and without gestational diabetes: the Diabetes Prevention Program outcomes study 10-year follow-up.

CONTEXT: Gestational diabetes (GDM) confers a high risk of type 2 diabetes. In the Diabetes Prevention Program (DPP), intensive lifestyle (ILS) and metformin prevented or delayed diabetes in women with a history of GDM. OBJECTIVE: The objective of the study was to evaluate the impact of ILS and metformin intervention over 10 years in women with and without a history of GDM in the DPP/Diabetes Prevention Program Outcomes Study. DESIGN: This was a randomized controlled clinical trial with an observational follow-up. SETTING: The study was conducted at 27 clinical centers. PARTICIPANTS: Three hundred fifty women with a history of GDM and 1416 women with previous live births but no history of GDM participated in the study. The participants had an elevated body mass index and fasting glucose and impaired glucose tolerance at study entry. INTERVENTIONS: Interventions included placebo, ILS, or metformin. OUTCOMES MEASURE: Outcomes measure was diabetes mellitus. RESULTS: Over 10 years, women with a history of GDM assigned to placebo had a 48% higher risk of developing diabetes compared with women without a history of GDM. In women with a history of GDM, ILS and metformin reduced progression to diabetes compared with placebo by 35% and 40%, respectively. Among women without a history of GDM, ILS reduced the progression to diabetes by 30%, and metformin did not reduce the progression to diabetes. CONCLUSIONS: Women with a history of GDM are at an increased risk of developing diabetes. In women with a history of GDM in the DPP/Diabetes Prevention Program Outcomes Study, both lifestyle and metformin were highly effective in reducing progression to diabetes during a 10-year follow-up period. Among women without a history of GDM, lifestyle but not metformin reduced progression to diabetes.

Long-term changes in dietary and food intake behaviour in the Diabetes Prevention Program Outcomes Study.

AIMS: To compare change in dietary intake, with an emphasis on food groups and food intake behaviour, over time across treatment arms in a diabetes prevention trial and to assess the differences in dietary intake among demographic groups within treatment arms. METHODS: Data are from the Diabetes Prevention Program and Diabetes Prevention Program Outcomes Study. Participants were randomized to a lifestyle intervention (n = 1079), metformin (n = 1073) or placebo (n = 1082) for an average of 3 years, after which the initial results regarding the benefits of the lifestyle intervention were released and all participants were offered a modified lifestyle intervention. Dietary intake was assessed using a food frequency questionnaire at baseline and at 1, 5, 6 and 9 years after randomization. RESULTS: Compared with the metformin and placebo arms, participants in the lifestyle arm maintained a lower total fat and saturated fat and a higher fibre intake up to 9 years after randomization and lower intakes of red meat and sweets were maintained for up to 5 years. Younger participants had higher intakes of poultry and lower intakes of fruits compared with their older counterparts, particularly in the lifestyle arm. Black participants tended to have lower dairy and higher poultry intakes compared with white and Hispanic participants. In the lifestyle arm, men tended to have higher grain, fruit and fish intakes than women. CONCLUSIONS: Changes in nutrient intake among participants in the lifestyle intervention were maintained for up to 9 years. Younger participants reported more unhealthy diets over time and thus may benefit from additional support to achieve and maintain dietary goals.

Research charting a course for evidence-based clinical dietetic practice in diabetes.

Nutrition and lifestyle interventions have been a critical component in three of the four largest clinical trials that focused on diabetes in the past two decades. Evidence of the effectiveness of nutrition and lifestyle interventions with resepect to achieving diabetes-related outcomes for diabetes prevention and a reduction in diabetes complications for people with diabetes is clearly mounting. The Diabetes Control and Complications Trial (1983-1993), the Diabetes Prevention Program (1996-2001) and the Look AHEAD (Action for Health in Diabetes) Trial (2001-2012) have been providing key evidence for the dietitian's role in delivering effective nutrition and lifestyle interventions for people with prediabetes, type 1 and type 2 diabetes. The dietitians in these multicentre efficacy trials contributed to this evidence base by expanding their roles beyond implementing the protocol defined goal-based nutrition and lifestyle interventions to conducting ancillary research and using problem-solving strategies that tailor counselling approaches toward participants' barriers to goal achievement. As lifestyle coaches and case managers, dietitians had the opportunity to work with the same group of study participants over extended periods of time and use their clinical and research expertise to uncover important insights and strategies that helped achieve clinical goals related to glycaemia control, weight loss and activity. The present review will 'chart the course' of how the evidence base for nutrition and lifestyle interventions emanated from these trials and discuss the implications for clinical dietetic practice. Dietitians can use insights gleaned from these experiences with the research process to expand their roles and guide cutting edge evidence-based clinical dietetic practice in diabetes.

An expanded role for dietitians in maximising retention in nutrition and lifestyle intervention trials: implications for clinical practice.

The demand for clinical trials targeting lifestyle intervention has increased as a result of the escalation in obesity, diabetes mellitus and cardiovascular disease. Little is published about the strategies that dietitians have used to successfully screen potential study volunteers, implement interventions and maximise adherence and retention in large multicentre National Institutes of Health funded nutrition and lifestyle intervention clinical trials. This paper discusses an expanded role for the contributions of dietitians as members of an interdisciplinary team based on research experiences in the Diabetes Control and Complications Trial, Diabetes Prevention Program and Look AHEAD (Action for Health in Diabetes). Many of the strategies and insights discussed are also relevant to effective clinical practice. Dietitians need to broaden their scope of practice so that they are integrated proactively into the screening and intervention phases of large clinical trials to maximise retention and adherence to assigned nutrition, lifestyle and behavioural interventions. The skills of dietitians are a unique fit for this work and it is important that investigators and project managers consider including them in both the screening and intervention phases of such clinical trials to maximise retention results.

Assessing gene-treatment interactions at the FTO and INSIG2 loci on obesity-related traits in the Diabetes Prevention Program.

AIMS/HYPOTHESIS: The single nucleotide polymorphism (SNP) rs9939609 in the fat mass and obesity associated gene (FTO) and the rs7566605 SNP located 10 kb upstream of the insulin-induced gene 2 gene (INSIG2) have been proposed as risk factors for common obesity. METHODS: We tested for genotype-treatment interactions on changes in obesity-related traits in the Diabetes Prevention Program (DPP). The DPP is a randomised controlled trial of 3,548 high-risk individuals from 27 participating centres throughout the USA who were originally randomised to receive metformin, troglitazone, intensive lifestyle modification or placebo to prevent the development of type 2 diabetes. Measures of adiposity from computed tomography were available in a subsample (n = 908). This report focuses on the baseline and 1 year results. RESULTS: The minor A allele at FTO rs9939609 was positively associated with baseline BMI (p = 0.003), but not with baseline adiposity or the change at 1 year in any anthropometric trait. For the INSIG2 rs7566605 genotype, the minor C allele was associated with more subcutaneous adiposity (second and third lumbar vertebrae [L2/3]) at baseline (p = 0.04). During follow-up, CC homozygotes lost more weight than G allele carriers (p = 0.009). In an additive model, we observed nominally significant gene-lifestyle interactions on weight change (p = 0.02) and subcutaneous (L2/3 [p = 0.01] and L4/5 [p = 0.03]) and visceral (L2/3 [p = 0.02]) adipose areas. No statistical evidence of association with physical activity energy expenditure or energy intake was observed for either genotype. CONCLUSIONS/INTERPRETATION: Within the DPP study population, common variants in FTO and INSIG2 are nominally associated with quantitative measures of obesity, directly and possibly by interacting with metformin or lifestyle intervention.

Differentiating symptoms of depression from diabetes-specific distress: relationships with self-care in type 2 diabetes.

AIMS/HYPOTHESIS: The aim of this study was to examine the relationship between depressive symptoms and diabetes-specific distress and the independent relationships of each of these factors with diabetes self-care. We expected that symptoms of depression would be associated with poorer diabetes self-care, independent of diabetes-specific distress. METHODS: We surveyed 848 primary care patients with type 2 diabetes using the Harvard Department of Psychiatry/National Depression Screening Day Scale (HANDS), Problem Areas in Diabetes scale (PAID), Summary of Diabetes Self-Care Activities, and self-reported medication adherence. RESULTS: The PAID and HANDS scores were positively correlated in the overall sample (r=0.54, p<0.0001), among those who did not meet diagnostic criteria for major depressive disorder (MDD) based on the HANDS screening result (n=685; r=0.36, p<0.001) and in patients who did meet the screening criteria for MDD (n=163; r=0.36, p<0.001). Higher PAID scores significantly predicted lower levels of diet, exercise and medication adherence (all p values <0.05). However, once depression symptom scores were entered into these models, most relationships were reduced to non-significance, while the HANDS score retained significant relationships with most indices of diabetes self-care. The same pattern of results was found in the subset of patients who did not screen positive for MDD. CONCLUSIONS/INTERPRETATION: These results suggest that specific symptoms of depression have a greater negative relationship with diabetes self-care than diabetes-specific distress, even among those patients who do not meet screening criteria for MDD. Interventions that focus on improving the management of specific symptoms of depression may be more effective in improving self-care than those that focus on reducing distress.

First versus repeat treatment with a lifestyle intervention program: attendance and weight loss outcomes.

OBJECTIVE: Following unblinding of the Diabetes Prevention Program (DPP) results, a 16-session lifestyle intervention program was offered to all study participants, including those who had initially been randomized to lifestyle treatment. This study compares the effects of the lifestyle program between participants who had previous exposure and those who had not. DESIGN: A 16-session behavioral intervention was conducted in groups at each of the 27 DPP sites during a transitional (bridge) period from the DPP trial to the DPP Outcomes Study (DPPOS). Session participation for this 6-month behavioral weight loss program was confirmed by originally randomized treatment groups. SUBJECTS AND MEASUREMENTS: Independently assessed weight measurements were available within a 7-month period before and after the program for 2808 ethnically diverse participants. RESULTS: Participants from the lifestyle group in the DPP were the least likely to attend a repeat offering of a 16-session behavioral weight loss program conducted in groups. Weight loss during the transitional lifestyle program was strongly related to the duration of attendance in the three groups that were participating in the program for the first time (metformin, placebo and troglitazone), but not related to amount of earlier weight loss. CONCLUSION: Individuals who were naive to the behavioral program lost a greater amount of weight and this was strongly related to their degree of participation. A second exposure to a behavioral weight loss program resulted in unsatisfactory low attendance rates and weight loss.

Symptoms of depression prospectively predict poorer self-care in patients with Type 2 diabetes.

AIMS: To examine prospectively the association of depression symptoms with subsequent self-care and medication adherence in patients with Type 2 diabetes mellitus. METHODS: Two hundred and eight primary care patients with Type 2 diabetes completed the Harvard Department of Psychiatry/National Depression Screening Day Scale (HANDS) and the Summary of Diabetes Self-Care Activities (SDSCA) at baseline and at follow-up, an average of 9 months later. They also self-reported medication adherence at baseline and at a follow-up. RESULTS: Baseline HANDS scores ranged from 0 to 27, with a mean score of 5.15 +/- 4.99. In separate linear regression models that adjusted for baseline self-care, patients with higher levels of depressive symptoms at baseline reported significantly lower adherence to general diet recommendations and specific recommendations for consumption of fruits and vegetables and spacing of carbohydrates; less exercise; and poorer foot care at follow-up (beta ranging from -0.12 to -0.23; P < 0.05). Similarly, each one-point increase in baseline HANDS score was associated with a 1.08-fold increase in the odds of non-adherence to prescribed medication at follow-up (95% confidence interval 1.001, 1.158, P = 0.047). Increases in depression scores over time also predicted poorer adherence to aspects of diet and exercise. CONCLUSIONS: Depressive symptoms predict subsequent non-adherence to important aspects of self-care in patients with Type 2 diabetes, even after controlling for baseline self-care. Although the relationship between symptoms of depression and poorer diabetes self-care is consistent, it is not large, and interventions may need to address depression and self-care skills simultaneously in order to maximize effects on diabetes outcomes.

Association of diabetes-related emotional distress with diabetes treatment in primary care patients with Type 2 diabetes.

AIMS: To characterize the determinants of diabetes-related emotional distress by treatment modality (diet only, oral medication only, or insulin). METHODS: A total of 815 primary care patients with Type 2 diabetes completed the Problem Areas in Diabetes (PAID) Scale and other questions. We linked survey data to a diabetes clinical research database and used linear regression models to assess the associations of treatment with PAID score. RESULTS: PAID scores were significantly higher among insulin-treated (24.6) compared with oral-treated (17.8, P < 0.001) or diet-treated patients (14.7, P < 0.001), but not different between oral- vs. diet-treated patients (P = 0.2). Group scores remained similar, but the statistical significance of their differences was reduced and ultimately eliminated after sequential adjustment for diabetes severity, HbA(1c), body mass index, regimen adherence, and self-blood-glucose monitoring. Insulin-treated patients reported significantly higher distress than oral- or diet-treated patients on 16 of 20 PAID items. 'Worrying about the future' and 'guilt/anxiety when ... off track with diabetes' were the top two serious problems (PAID >or= 5) in all treatment groups. Not accepting diabetes diagnosis was a top concern for oral- and diet-treated patients, and unclear management goals distressed diet-treated patients. CONCLUSIONS: Primary care patients treated with insulin reported higher diabetes-related emotional distress compared with oral- or diet-treated patients. Greater distress was largely explained by greater disease severity and self-care burdens. To improve diabetes-specific quality of life, clinicians should address patients' sense of worry and guilt, uncertain acceptance of diabetes diagnosis, and unclear treatment goals.

Clinical and cost outcomes of medical nutrition therapy for hypercholesterolemia: a controlled trial.

OBJECTIVE: To compare the results and cost-effectiveness of a cholesterol lowering protocol implemented by registered dietitians with cholesterol lowering advice by physicians. DESIGN: Six month randomized controlled trial, cost-effectiveness analysis. Subjects included 90 ambulatory care patients (60 men, 30 women), age range 21 to 65 years, with hypercholesterolemia and not taking hypolipidemic drugs. Patients were randomly assigned to receive medical nutrition therapy (MNT) from dietitians using a NCEP based lowering protocol or usual care (UC) from physicians. Outcome measures were plasma lipid profiles, dietary intake, weight, activity, patient satisfaction, and costs of MNT. Changes from baseline for each variable of interest were compared between treatment groups using analysis of covariance controlling for baseline value of the variable and gender. RESULTS: MNT achieved a 6% decrease in total and LDL cholesterol levels at 3 and 6 months compared with a 1% increase and a 2% decrease in both values at 3 and 6 months with UC (P<.001 and P<.05, respectively). Weight loss (1.9 vs 0 kg, P<.001) and dietary intake of saturated fat (7% of energy vs 10%, P<.001) were better in the MNT than the UC group. The additional costs of MNT were $217 per patient to achieve a 6% reduction in cholesterol and $98 per patient to sustain the reduction. The cost-effectiveness ratio for MNT was $36 per 1% decrease in cholesterol and LDL level. APPLICATIONS/CONCLUSIONS: MNT from registered dietitians is a reasonable investment of resources because it results in significantly better lipid, diet, activity, weight, and patient satisfaction outcomes than UC.

Implications of the diabetes control and complications trial for renal outcomes and medical nutrition therapy.

The Diabetes Control and Complications Trial (DCCT) results have important implications related to the prevention and management of diabetic nephropathy. This paper provides an overview of the study design, methods and overall results with particular emphasis on renal outcomes and the role of medical nutrition therapy. The DCCT demonstrated that intensive diabetes therapy aimed at near normoglycemia resulted in a 39% reduction in the occurrence of microalbuminuria and a 54% reduction in the occurrence of albuminaria. Further analysis of DCCT data show that the impact of intensive therapy on renal outcomes may vary based on the stage of diabetic nephropathy, gender and prior exposure to hyperglycemia. This review highlights the clinical implications of the DCCT results for dietitians, nurses and physicians working with patients with diabetic nephropathy and describes post-DCCT advances in clinical practice and research.

Macronutrient and energy database for the 1995 Exchange Lists for Meal Planning: a rationale for clinical practice decisions.

For more than 50 years the exchange lists have been one method of meal planning for persons with diabetes as well as for those on weight-loss regimens. Little research has been conducted, however, concerning the methodologic basis of the system or its clinical effectiveness. Justification for specific food inclusions and general food groupings for the 1995 revision of the Exchange Lists for Meal Planning is provided by a database of foods and associated energy and macronutrient values. The mean energy and macronutrient values for each of the lists and sublists (starch, fruit, milk, and vegetables from the carbohydrate group; the meat and meal substitutes group, and the fat group) closely match the mean exchange values; however, the standard deviation and range are large. Interpretation of the database provides a rationale and guidance for decision making in clinical practice when using exchanges for meal planning, recipe, and food label calculations.

The role of diet behaviors in achieving improved glycemic control in intensively treated patients in the Diabetes Control and Complications Trial.

OBJECTIVE: To determine whether specific diet-related behaviors practiced by IDDM patients in the intensive treatment group of the Diabetes Control and Complications Trial were associated with lower HbA1c values. RESEARCH DESIGN AND METHODS: A questionnaire addressing various aspects of their dietary behavior during the previous year in the DCCT was completed by 623 DCCT intensive treatment group subjects. The association between self-reported diet behaviors and the subject's mean HbA1c during the previous year was evaluated using a linear rank test for trend. The goal of intensive treatment was to achieve blood glucose and HbA1c levels as close to the nondiabetic range as possible without hypoglycemia. RESULTS: Adherence to the prescribed meal plan and adjusting food and/or insulin in response to hyperglycemia were significantly associated with lower HbA1c levels. Over-treating hypoglycemia and consuming extra snacks beyond the meal plan were associated with higher HbA1c levels. Adjusting insulin dose for meal size and content and consistent consumption of an evening snack were associated, albeit to a lesser degree, with lower HbA1c. CONCLUSIONS: The average HbA1c among intensively managed patients who reported that they followed specific diet-related behaviors was 0.25 to 1.0 lower than among subjects who did not follow these behaviors. Health-care providers may wish to use these results to focus clinical care for intensively treated IDDM patients by emphasizing counseling on meal plans, prompt response to high blood glucose levels, appropriate treatment of hypoglycemia, and consistent snacking behaviors.

Geriatric team dynamics: the dietitian's role.

In 1980, a geriatric consultation team was formed at Massachusetts General Hospital to meet the complex medical, psychological, rehabilitative, nutritional, and social needs of geriatric patients. This team strives to provide elderly patients with the comprehensive care necessary to potentiate return to maximum independent functioning and to change attitudes of primary caretakers toward care of geriatric patients through increased recognition of the elderly as a heterogeneous group. The team consults on patients with changes in mental status, need for physical rehabilitation, "failure to thrive," or need for definitive planning for posthospital disposition. The dietitian conducts nutritional screening of each patient, is a nutrition resource for team members, and promotes collaboration in nutrition care planning. When the dietitian communicates nutrition concerns, goals, and care plans for patients to other health professionals, they use the information to reinforce her recommendations and integrate nutrition components into their care plans. A multidisciplinary approach has resulted in earlier identification and evaluation of functional ability, more comprehensive individualized care planning, and a reduced percentage of readmissions.