P

IPfL

ATAtdotiodftttlwimtmkietpdJ

Tb

LtrG

p

Rp

A

S

RESEARCH

erspectives in Practice

mplications of the Diabetes Preventionrogram and Look AHEAD Clinical Trials

or Lifestyle Interventions

INDA M. DELAHANTY, MS, RD; DAVID M. NATHAN, MD

pt(pssPlfbotcldcaddt

ptgAifst

CDvaotaAleptpbbtsu

BSTRACThe Diabetes Prevention Program (DPP) and LookHEAD (Action for Health in Diabetes) trials are long-

erm randomized clinical trials that have the potential toirect diabetes care and medical nutrition therapy forbesity, prediabetes, and type 2 diabetes both now and inhe future. This article summarizes and compares themportant evidence-based results of these diabetes andbesity clinical trials and reviews the similarities andifferences in lifestyle interventions that were designedor these trials. Although there were many similarities inhe features of the DPP and Look AHEAD interventions,he Look AHEAD lifestyle intervention was more ambi-ious in several ways: higher individual weight-loss goals,ower calorie and fat-gram targets based on initial bodyeight, more intensive intervention frequency, combin-

ng closed group and individual session format, and use ofore structured nutrition intervention strategies from

he outset, including meal replacements, structuredenus, and combined fat and calorie counting. Evidence,

nowledge, and insights gained from working on these clin-cal trials will be very important in determining the strat-gies, methods, and approaches needed to make sure thathe results of these trials will be fully applied in real-worldractice settings for obesity, prediabetes, and type 2iabetes.Am Diet Assoc. 2008;108:S66-S72.

he Diabetes Prevention Program (DPP) and its fol-low-up, the Diabetes Prevention Program OutcomesStudy, and Look AHEAD (Action for Health in Dia-

etes), are long-term randomized clinical trials that have

. M. Delahanty is chief dietitian and director of Nutri-ion and Behavioral Research and D. M. Nathan is di-ector, both at MGH Diabetes Center, Massachusettseneral Hospital, Boston.STATEMENT OF CONFLICT OF INTEREST: See

age S72.Address correspondence to: Linda M. Delahanty, MS,D, MGH Diabetes Center, Massachusetts General Hos-ital, 50 Staniford St, Suite 340, Boston, MA 02114.Manuscript accepted: October 19, 2007.Copyright © 2008 by the American Dietetic

ssociation.0002-8223/08/10804-1011$34.00/0

odoi: 10.1016/j.jada.2008.01.026

66 Supplement to the Journal of the AMERICAN DIETETIC ASSOCIATION

otential to direct diabetes care and medical nutritionherapy for obesity, prediabetes, and type 2 diabetesT2DM) both now and in the future. DPP results haverovided practitioners and third-party insurers withtrong evidence regarding the beneficial impact of life-tyle intervention on development of diabetes. Diabetesrevention Program Outcomes Study is determining how

ong lifestyle changes can be sustained with minimalollow-up and how long diabetes and its complications cane prevented or delayed in an ethnically diverse group ofverweight patients with prediabetes. The Look AHEADrial, in overweight people with T2DM, is designed toompare effects of a lifestyle intervention aimed at weightoss, and modeled after the DPP program, with a stan-ardized program of diabetes education and support onardiovascular outcomes. Similar to the impact DPP/Di-betes Prevention Program Outcomes Study has had oniabetes prevention, the 12-year Look AHEAD trial willefine the role of lifestyle intervention and medical nu-rition therapy in management of T2DM.

This article will summarize and compare the design,opulation characteristics, and available results ofhe primary prevention DPP/Diabetes Prevention Pro-ram Outcomes Study and secondary intervention LookHEAD clinical trials; review similarities and differences

n their lifestyle interventions; and discuss implicationsor implementing lifestyle intervention programs for obe-ity, prediabetes, and T2DM in real-world practice set-ings.

LINICAL CHARACTERISTICS OF DPP AND LOOK AHEADPP was designed to determine whether a lifestyle inter-ention directed at reducing body mass and increasingctivity levels, or the medication metformin, would delayr prevent development of diabetes in a high-risk popula-ion (1). The study was planned between 1994 and 1996nd recruitment began in 1996. The ongoing LookHEAD study, planned between 1999 and 2001 and

aunched in 2001 after successful completion of DPP, ismploying a similar lifestyle intervention, but instead ofrimary prevention, is examining effects of lifestyle in-ervention on occurrence of cardiovascular disease in peo-le with T2DM (2). The eligibility criteria and resultantaseline characteristics of DPP and Look AHEAD haveeen described (1-4). Each study recruited a populationhat would satisfy its particular goals. DPP recruitedubjects who were representative of the prediabetic pop-lation and at high risk for developing diabetes by virtue

f being overweight, having impaired glucose tolerance,

© 2008 by the American Dietetic Association

amampappydt

hbm(CAC

vsgtvflcl

atpp

suppyc

LTLloatitiaptd

nd fasting glucose levels that were generally above theedian for impaired glucose tolerance (1,3) (Table 1). In

ddition, DPP aimed to enroll a population enriched withinority racial-ethnic groups (African American, His-

anic American, Asian American and Pacific Islander,nd American Indian) that had been identified as being atarticularly high-risk for developing T2DM. The studyrojected a hazard rate of developing diabetes of 7.5% perear. In fact, the placebo-treated group had a higher rateuring the study (�11% per year), which contributed tohe study’s early termination.

Look AHEAD recruited a population of patients whoad already developed T2DM to determine the putativeenefits of a lifestyle intervention, similar to that imple-ented in DPP, on development of cardiovascular disease

CVD) over time (2). To enrich the rate of development ofVD events during the projected 12-year study, LookHEAD included some patients who had already had aVD event.While these two studies, bound together through pro-

ision of a similar lifestyle intervention, had differentpecific goals, they both sought to delay the usual pro-ression of dysglycemic states from prediabetes to diabe-es and then to long-term complications. Lifestyle inter-entions addressed the underlying “environmental”actors, specifically overweight, obesity, and sedentaryifestyle, which are widely accepted as central to in-reased risk of developing diabetes and, in turn, to its

Table 1. Eligibility criteria and baseline characteristics of recruited

DPP eligibilitycriteria

DPP bacharac

n 3,000 3,234Age (y) �25 50.6�1Sex (% women) 50 67.7Race (%)

NHWe 50 54.7African American

50

19.9Hispanic American 15.7Asian American/PIf 4.4American Indian 5.3

BMIg �24h 34�6Glucosej levels (mg/dL)

Fasting 95-125 107�82-Hour OGTTk 140-199 165�1

HbA1cm (%) 5.91�0

aDPP�Diabetes Prevention Program.bAHEAD�Action for Health in Diabetes.cMean�standard deviation.dChanged to 55-74 during 2nd year.eNHW�non-Hispanic white.fPI�Pacific Islander.gBMI �body mass index (calculated as kg/m2).h�22 in Asian Americans.i�27 if taking insulin.jTo convert mg/dL glucose to mmol/L, multiply mg/dL by 0.0555. To convert mmol/L gkOGTT�oral glucose tolerance test.lMean�standard error.mHbA1c�hemoglobin A1c.

ong-term complications. The studies were designed to A

April 2008 ●

ddress the metabolic continuum at different points inhe preclinical and clinical course. In the United States,rediabetes and diabetes affect as many as 60 millioneople (5).The major recruitment criteria and profiles of the two

tudy populations at baseline are shown in Table 1. Pop-lations recruited represent two discrete slices of therediabetes to diabetes continuum. Not surprisingly, therediabetes cohort in DPP was approximately 8 yearsounger and slightly less overweight than the diabeticohort in Look AHEAD.

IFESTYLE INTERVENTION IN DPP AND LOOK AHEAD DESIGNhe major features of lifestyle interventions in DPP andook AHEAD are summarized in Figure 1. The DPP

ifestyle intervention program has been described previ-usly (6) and content and intervention materials arevailable at www.bsc.gwu.edu/dpp/index.html. Much ofhe content and materials used in Look AHEAD lifestylentervention were adapted from DPP materials and thenailored for patients with T2DM (7). Intervention sessionsn both trials focused on similar nutrition, behavioral,nd activity topics during the first year. In addition, bothrograms offered refresher programs and campaigns twoo three times per year, which were similar in content anduration (6,7).At first glance, it is clear that both DPP and Look

ts for DPPa and Look AHEADb

eics

Look AHEADeligibility criteria

Look AHEAD baselinecharacteristics

5,000 5,12545-74d 58.7�6.8c

50 59.4

�67 63.215.613.21.05.1

�25i 36.0�6c

153�0.9l

�11 7.27�0.2c

to md/dL, multiply mmol/L by 18.0. Glucose of 108 mg/dL�6.0 mmol/L.

cohor

selinterist

0.7c

.7c

.3c

7c

.5c

lucose

HEAD programs focused on the same process features:

Supplement to the Journal of the AMERICAN DIETETIC ASSOCIATION S67

(c(fetsvpii

GTwacoWsLbl

mib

cm2cb11kg5kAf

mwbh

Fa mea

S

a) goal-setting for weight, activity, and fat-gram andalorie intake; (b) self-monitoring to achieve these goals;c) frequent contact to provide accountability and sustainocus; (d) use of problem-solving and other “toolbox” strat-gies to address goals and potential barriers to achievinghem; and (e) emphasis on managing individual high-riskituations. However, closer examination of these inter-entions reveals several differences that might help ex-lain differences in weight-loss results at 1 year andnform efforts to translate these programs and resultsnto practice.

oal-Settinghe DPP weight-loss goal of losing 7% of initial bodyeight was based on results of previous weight-loss tri-ls, perceived feasibility of achieving the goal in a multi-enter trial, and epidemiologic data supporting this levelf weight loss as effective in reducing diabetes risk (6).hile both DPP and Look AHEAD interventions set

tudy-wide weight-loss goals of 7% of initial body weight,ook AHEAD set individual weight-loss goals of 10%,ased on success of DPP, evidence that larger weight

DPP

Weight-loss goal

Study goal=7% of iniIndividual goal=7% oweight

Activity goal 150 minutes per weekIntervention format Individual sessions

Frequency of follow-up

16 sessions in the firswith minimum of onefollow-up every 2 mothereafter

Refresher groups/campaigns

Three times per year months

Supervised activity sessions

Two times per week tthe trial

Nutrition intervention

Fat-gram counting wicalorie counting as neselected diet

Meal replacements Recommended as a tocampaign strategy

Basic toolbox strategies (to improve or maintain weight loss or physical activity)

Used throughout the ibased on identificatioto achieving activity aloss goals: problem-sostrategies and no-costreinforcers for fulfillicontracts

Advanced toolbox strategiesa

Higher-cost items usebarriers to weight lossafter first 6 months onlow-cost options had tried

igure 1. Comparison of lifestyle intervention features of Diabetes PExamples of advanced toolbox strategies could be provision of frozen

osses are generally associated with greater improve- p

68 April 2008 Suppl 1 Volume 108 Number 4

ents in outcomes, and speculation whether DPP partic-pants would have lost more weight if a higher goal hadeen set (7).To help achieve its weight-loss goals, DPP set daily

alorie goals that were 500 to 1,000 calories below weightaintenance, with the aim of achieving weight loss of 1 topounds per week. Fat-gram goals were based on 25% of

alories from fat. Four standard calorie levels were used,ased on initial body weights: 1,200 kcal/day (33 g fat) for20 to 170 lb; 1,500 kcal/day (42 g fat) for 175 to 215 lb;,800 kcal/day (50 g fat) for 220 to 245 lb; and 2,000cal/day (55 g fat) for �250 lb (6). Look AHEAD calorieoals were more ambitious: 1,200 to 1,500 kcal/day (40 to0 g fat) for initial weights �250 lb and 1,500 to 1,800cal/day (50 to 60 g fat) for initial weights �250 lb. LookHEAD fat-gram goals were set at �30% of calories from

at (7).The DPP activity goal of 150 minutes per week ofoderate-intensity physical activity, similar to a briskalk, was selected because evidence supported its feasi-ility and effectiveness, and it was consistent with publicealth recommendations and the Surgeon General’s Re-

Look AHEAD trial eight ial

Study goal was 7% of initial weight Individual goal was 10% of initial weight 175 minutes per week Group plus individual sessions

onths, rson

24 sessions in the first 6 months; 18 sessions in months 7 to 12; minimum of monthly individual sessions years 2 to 4

irst 6 Two to three times per year in years 2 and beyond

hout Periodically in refreshers or campaigns

dition of ; self-

Calorie counting with inclusion of fat-gram counting; portion-controlled diet

x or Recommended as a regular part of the portion-controlled diet and campaigns

ention arriers eight-

w-cost havioral

Used in first 6 months for difficulty reaching weight-loss and activity goals: problem-solving, motivational interviewing, and behavioral contracts

ddress activity -cost or y been

Used after the first 6 months if participants did not meet activity goal or lose 5% of initial weight or regained 2% or more from lowest weight; includes use of higher-cost items, including weight-loss medication

tion Program (DPP) and Look AHEAD (Action for Health in Diabetes).ls or exercise items.

tial wf init

t 6 m in-penths

after f

hroug

th adeded

olbo

ntervn of bnd wlving

or long be

d to a and ce no

alread

reven

ort on Physical Activity and Health (8). The 150-minute

pf7dwTDt

motou

SDaiHdptfrtBt

ITucwminesa

presssmymb

frtlfi(gc

mdfi

NTDmpchscledwp

foppmteottitfat

TTiateibctphbd

pstfewulf

er week goal could include up to 75 minutes per weekrom strength training and would expend approximately00 kcal. DPP lifestyle participants were encouraged toistribute their activity during at least 3 days per week,ith at least 10 minutes of physical activity per session.o support participants in achieving activity goals, eachPP center offered supervised activity sessions at least

wo times per week throughout the trial (6).Look AHEAD’s physical activity goal was set at 175inutes per week, again based on the success of DPP, and

n findings that higher levels of physical activity substan-ially improve weight-loss maintenance and other healthutcomes (7,9). Look AHEAD’s activity program reliespon unsupervised (at-home) exercise.

elf-MonitoringPP developed a fat and calorie counter booklet thatddressed needs of a culturally diverse population andncluded foods commonly consumed by African-American,ispanic-American, Asian-American, and American In-ian subgroups. DPP self-monitoring booklets helpedarticipants track food portions, fat-gram and calorie in-ake, and activity minutes. Look AHEAD used the sameat and calorie counter and food and activity diary. Theseesources are available at www.ndep.nih.gov, as part ofhe National Diabetes Education Program “Small Stepsig Rewards Program: Prevent Type 2 Diabetes” toolkit

hat was developed based on DPP results (10).

ntervention Frequency and Formathe DPP lifestyle intervention was delivered by individ-al lifestyle coaches. Participants received a 16-week coreurriculum during the first 6 months (approximatelyeekly contact) and then had at least one contactonthly for the remainder of the study (at least one

n-person visit every 2 months, with phone visits aseeded to maintain once per month contact) (6). On av-rage, lifestyle participants attended 23.6�7.1 individualessions during year 1, 12.5�7.1 sessions during year 2nd 50.3�21.8 sessions during the entire trial (11).The Look AHEAD intervention is delivered in a group

lus individual format by intervention teams that includeegistered dietitians (RDs), behavioral psychologists, andxercise specialists. Participants are offered weekly ses-ions, with three group sessions and one individual ses-ion per month in the first 6 months and two groupessions and one individual session per month duringonths 7 to 12, a total of 42 sessions the first year. In

ears 2 to 4, participants are offered a minimum ofonthly individual sessions and one additional contact

y group, phone, mail, or e-mail (7).Individual sessions in DPP and Look AHEAD ranged

rom 20 to 60 minutes and included private weigh-in,eview of self-monitoring records, presentation of a newopic, ongoing identification of personal barriers to weightoss and activity, and development of action plans/goalsor the next session (6,7). Group sessions in Look AHEADnclude the same 10 to 20 participants for the first yearclosed groups) and range from 60 to 75 minutes. Theroup format includes the same private weigh-in, group

heck-ins to self-report on progress with weight, self- p

April 2008 ●

onitoring, and goal-setting, presentation of a new topic,iscussion and problem-solving of ongoing barriers, identi-cation of action plans, and homework for next session (7).

utrition Intervention Strategyhe main focus of the nutrition intervention strategy inPP started with a self-discovery process through self-onitoring of food intake and fat-gram intake. Partici-

ants learned that there were three ways to eat less fat:hoose high-fat foods less often, eat smaller portions ofigh-fat foods, or substitute lower-fat foods. For the firsteven sessions, participants focused only on fat-gramounting. Then, if they were not on track for a 7% weightoss at session 7, they would also receive a calorie goal tonhance progress with weight loss on their self-selectediet. Meal replacements and structured menus or mealsere optional toolbox items that coaches could use witharticipants to enhance weight loss (7).In Look AHEAD, the nutrition intervention strategy

ocused on calorie-counting with fat-gram goals and usef meal replacements as part of the intervention for allarticipants from the outset. For the first 4 to 16 weeks,articipants were encouraged to use two meal replace-ents and two snack replacements per day, and struc-

ured menus for their main meal. After that, they werencouraged to transition to one meal replacement andne snack replacement per day and continue with struc-ured menus and meals and a portion-controlled diet forhe remainder of the day (7). Look AHEAD nutritionntervention strategies were chosen based on evidencehat combining fat and calorie counting vs calorie orat-gram counting alone, and using meal replacements vs

self-selected diet from the outset resulted in substan-ially greater weight losses (7,12,13).

oolbox Approacheshroughout DPP, coaches worked with each participant

ndividually to identify personal barriers to achievingctivity and weight-loss goals. They could use a variety ofoolbox approaches to help participants deal with barri-rs. Toolbox approaches were used in hierarchical fash-on, such that low-cost or no-cost approaches (in terms ofoth staff time and money) were used first and higher-ost approaches were used after low-cost approaches wereried. The most common toolbox approaches used wereroblem-solving and use of reinforcers for fulfilling be-avioral contracts. Examples of higher-cost items mighte the purchase of walking shoes, a cookbook, frozeninners, or enrollment in a community class (6,14).In Look AHEAD, basic and more-advanced toolbox ap-

roaches were designed with specific criteria for use. Ba-ic toolbox strategies, such as problem-solving, motiva-ional interviewing, and behavioral contracts, were usedor participants who had difficulty adhering to diet andxercise recommendations, or who were losing �1% ofeight per month. Advanced toolbox approaches weresed after the first 6 months for participants who failed to

ose 5% of initial weight or who had regained 2% or morerom their lowest weight (7).

In Look AHEAD, advanced toolbox items could include

rovision of frozen meals, community classes, exercise

Supplement to the Journal of the AMERICAN DIETETIC ASSOCIATION S69

ihaoPwer

fLilwifsiLmwtnp

LDasi1pA

LTstlsaiDamit(

MIldwDymtma

oa

oilCssCoardpistt(L

TIBtpcDsta(m(

Ibfsty

S

tems, or use of weight-loss medication. Thus far, orlistatas been the only weight-loss medication in the toolbox,nd it is only offered as an option to those who lost �5%f initial weight or regain �2% from their lowest weight.articipants who lose and maintain �10% of initialeight are not eligible for weight-loss medication; how-ver, those who lose 5% to 9.9% of initial weight canequest it (4,7).In summary, although there were many similarities in

eatures of DPP and Look AHEAD lifestyle interventions,ook AHEAD’s lifestyle intervention was more ambitious

n several ways: higher individual weight-loss goals;ower calorie and fat-gram targets based on initial bodyeight; more intensive intervention frequency capitaliz-

ng on advantages of both closed group and individualormats; and more structured nutrition-interventiontrategies that combined fat and calorie counting andncorporated use of meal replacements from the outset.ook AHEAD’s lifestyle intervention was planned to beore ambitious because people with T2DM enrolled ineight-loss programs have traditionally lost less weight

han their nondiabetic counterparts and because of theeed to produce weight loss over 12 years to answer therimary study question.

IFESTYLE INTERVENTION IN DPP AND LOOK AHEAD RESULTSPP completed its major clinical trial phase in 2001, afterpproximately 3 years mean study duration and 1 yearooner than its planned duration. Look AHEAD is ongo-ng and is approximately halfway through its anticipated2-year duration. The currently available data allow com-arison of weight-loss results at 1 year for DPP and LookHEAD.

ifestyle Changes: Intermediate Outcomeshe Look AHEAD lifestyle intervention borrowed exten-ively from DPP’s protocol; therefore, similar results inhe two studies with regard to weight loss and activityevels would not be surprising. However, differences intudy populations reviewed here; potential impact of di-betes medications on weight change in Look AHEAD;mplementation of lifestyle interventions individually inPP, but in groups in Look AHEAD; and differences,lbeit modest, in lifestyle goals between the two studies,ight have resulted in different outcomes. In fact, the

ntermediate outcomes of the lifestyle interventions inhe two studies were remarkably more similar than notTable 2).

ajor Study Outcomesn DPP, lifestyle intervention was highly effective in de-aying onset of diabetes, reducing the cumulative inci-ence by 58% compared with placebo. Similar resultsere achieved with lifestyle intervention in the Finnishiabetes Prevention study (15). Of note, secondary anal-ses of DPP revealed that weight loss appeared to be theajor mediator of diabetes prevention, with physical ac-

ivity levels playing a “supporting role” by helping toaintain weight loss (16). Look AHEAD has not reported

ny interim outcome results of its lifestyle intervention, D

70 April 2008 Suppl 1 Volume 108 Number 4

ther than the intermediate weight loss already noted,nd CVD risk factors reviewed later.In addition to the salutary effect of lifestyle intervention

n diabetes prevention, reduction in diabetes complications,ncluding CVD, is an important goal of the ongoing fol-ow-up to DPP, the DPP Outcomes Study. Reduction inVD outcomes is the primary goal of Look AHEAD. Bothtudies will require more years of follow-up to demon-trate the putative effects of lifestyle intervention onVD; however, a beneficial effect of lifestyle interventionn CVD risk factors has been demonstrated after 3 yearsnd 1 year of follow-up in DPP and Look AHEAD studies,espectively (4,17) (Table 3). Lifestyle intervention in pre-iabetes and diabetes results in improvements in bloodressure and lipids, in addition to weight loss and phys-cal conditioning. In addition, DPP lifestyle interventionubstantially reduced levels of nontraditional risk fac-ors, including C-reactive protein and fibrinogen relativeo placebo and, to a lesser degree, relative to metformin18). Comparable analyses have not yet been reported inook AHEAD.

RANSLATING EVIDENCE-BASED LIFESTYLE INTERVENTIONSNTO COMMUNITY RESEARCH AND CLINICAL PRACTICEecause Look AHEAD is still in progress, studies inves-

igating means of translating its results into communityractice have not yet been conducted. However, an in-reasing number of studies are investigating translatingPP results (19-26). These DPP translational research

tudies have demonstrated that DPP lifestyle interven-ion can be successfully implemented in various settings;

diabetes education center and medical fitness facility19), primary care settings (20), urban underserved com-unities (19,21,22), YMCAs (21), Latino communities

22), and employee worksites (24,25).As a result of United States Congressional direction,

ndian Health Service (IHS) established the Special Dia-etes Program for Indians Diabetes Prevention Project tound activities based on DPP, including (a) diabetescreening, (b) recruitment of individuals with “prediabe-es” into programs (approximately 50 per year for 3ears), (c) implementation of group classes providing the

Table 2. DPPa and Look AHEADb lifestyle goals and results after 1year of intervention

DPPgoals

DPPresults

LookAHEADgoals

LookAHEADresultsc

Weight change frombaseline% reduction �7 7.2 �7 8.6

Activity levels (min/week) 150 208 175 NAd

aDPP�Diabetes Prevention Program.bAHEAD�Action for Health in Diabetes.cMean follow-up 1 year (3,4,7).dNA�not available; activity level in minutes per week has not yet been published forthe Look AHEAD study.

PP’s 16-session education curriculum, and (d) individ-

uitTtTD2

CDticTsopse

pl

bpitv

lfvsBAdcmsttacbifolrmta

t

Fa

D

al lifestyle coaching sessions, exercise programs, cook-ng and shopping demonstrations, and follow-up supporto reinforce the curriculum program. Currently, 36ribal, IHS, and Urban Indian programs nationwide par-icipate in the program (personal communication,ammy L. Brown, MPH, RD, Nutrition Consultant, IHSivision of Diabetes Treatment and Prevention, July 16,007).The Diabetes Primary Prevention Initiative, funded byenters for Disease Control and Prevention’s Division ofiabetes Translation, has funded five Diabetes Preven-

ion and Control Programs to design and implement pilotnterventions adapted from DPP in California, Massa-husetts, Michigan, Minnesota, and Washington State.hese programs focus on interventions, surveillance, andystems dynamics modeling and are targeting health carerganizations, local worksites, educators, primary careractices, community-based lifestyle intervention re-ources, YMCA programs, and clinic and communityvents to conduct diabetes screenings.More full-scale translational research trials are

lanned and RDs need to consider how they might trans-ate these evidence-based interventions into practice.

Figure 2 represents a conceptual model for evidence-ased translation of DPP and Look AHEAD into clinicalractice using individual, group, or combined group andndividual formats. This process starts with helping pa-ients determine, through a behavioral screening inter-

Table 3. Effects of DPPa and Look AHEADb lifestyle interventions onglycemia and cardiovascular disease risk factors

DPPc

(n�1,079)Look AHEADd

(n�2,496)

HbA1ce (%) NAf �0.64�0.02g

Fasting plasma glucose(mg/dL)h NAf �21.5�0.9g

Blood pressure (mm Hg)Systolic �3.3�0.5g �6.8�0.4g

Diastolic �3.8�0.3g �3.0�0.2g

LDLi cholesterol (mg/dL)j NSk �5.2�0.6HDLl cholesterol (mg/dL)j �1.0g �3.4�0.2g

Triglycerides (mg/dL)m �25.4g �30.3�2.0g

aDPP�Diabetes Prevention Program.bAHEAD�Action for Health in Diabetes.cMean follow-up of �3.0 years (3,17).dMean follow-up 1 year (4,7).eHbA1c�hemoglobin A1c.fNA�specific results not available; however, for approximate results, see Figure 3 inreference 3.g�0.001 compared with control group.hTo convert mg/dL glucose to mmol/L, multiply mg/dL by 0.0555. To convert mmol/Lglucose to mg/dL, multiply mmol/L by 18.0. Glucose of 108 mg/dL�6.00 mmol/L.iLDL�low-density lipoprotein.jTo convert mg/dL cholesterol to mmol/L, multiply mg/dL by 0.0259. To convert mmol/Lcholesterol to mg/dL, multiply mmol/L by 38.7. Cholesterol of 193 mg/dL�5.00mmol/L.kNS�not significant.lHDL�high-density lipoprotein.mTo convert mg/dL triglycerides to mmol/L, multiply mg/dL by 0.0113. To convertmmol/L triglycerides to mg/dL, multiply mmol/L by 88.6.

iew process, whether or not they are ready to commit to g

April 2008 ●

ifestyle change and what type of program is best suitedor them. Once readiness is established, RDs can reviewarious weight-loss trajectories that would be consideredafe, realistic, efficacious, and successful for 6 months.ecause calorie and fat-gram goals for DPP and LookHEAD were somewhat different, RDs can review theseistinctions with clients and help them choose fat andalorie goals that are achievable, based on assessment ofotivation and usual eating habits. Because both self-

elected and structured diet approaches have been showno be effective, RDs can review advantages and disadvan-ages of each, offer patients a menu approach to selecting

nutrition intervention strategy, and then agree uponalorie and fat-gram goals, an individual, group, or com-ined individual and group format, type of self-monitor-ng (related to weight, food, activity), and frequency ofollow-up needed to support goal achievement. Every stepf the process described in Figure 2 helps patients estab-ish realistic goals that are achievable; receive positiveeinforcement for those achievements; and learn self-onitoring skills, problem-solving skills, and self-motiva-

ional strategies that contribute to increased self-efficacynd satisfactory results.As researchers and practitioners, RDs are in key roles

o make sure the evidence, knowledge, and insights

igure 2. Translating lifestyle interventions to clinical practice settings.DPP�Diabetes Prevention Program. bAHEAD�Action for Health iniabetes.

ained from working in clinical trials are translated and

Supplement to the Journal of the AMERICAN DIETETIC ASSOCIATION S71

ftttplspistisld

Stst

R

1

1

1

1

1

1

1

1

1

1

2

2

2

2

2

2

2

S

ully applied in both community-based research and prac-ice. RDs in DPP and Look AHEAD received annualraining focused on effective delivery of lifestyle interven-ion sessions; extensive use of case presentations; role-laying; and clinical practice skills, such as reflectiveistening, motivational interviewing, and empowermenttrategies. Most centers also had a part-time behavioralsychologist who could help RDs address chronic behav-oral barriers to diet and exercise adherence (6,7). RDshould seek opportunities to refine their skills and iden-ify what roles they might play in establishing or partic-pating in community programs and translational re-earch so they are positioned to effectively apply lessonsearned in DPP and Look AHEAD and help combat theual epidemics of obesity and T2DM.

TATEMENT OF CONFLICT OF INTEREST: The au-hors have no conflict of interest to report with the spon-or of this supplement article or products discussed inhis article.

eferences1. Diabetes Prevention Program Research Group. The Diabetes Preven-

tion Program: Design and methods for a clinical trial in the preventionof type 2 diabetes. Diabetes Care. 1999;22:623-634.

2. Look AHEAD Research Group. Look AHEAD (Action for Health inDiabetes): Design and methods for a clinical trial of weight loss for theprevention of cardiovascular disease in type 2 diabetes. Con ClinTrials. 2003;24:610-628.

3. Diabetes Prevention Program Research Group. Reduction in the inci-dence of type 2 diabetes with lifestyle intervention or metformin.N Engl J Med. 2002;346:393-403.

4. Look AHEAD Research Group. Reduction in weight and cardiovascu-lar disease risk factors in individuals with type 2 diabetes. DiabetesCare. 2007;30:1374-1383.

5. National Diabetes Surveillance System: Data and Trends. Atlanta,GA: National Center for Chronic Disease Prevention and HealthPromotion, Centers for Disease Control and Prevention. Centersfor Disease Control and Prevention Web site. http://www.cdc.gov/diabetes/statistics/index.htm. Accessed July 24, 2007.

6. The Diabetes Prevention Program Research Group. The DiabetesPrevention Program (DPP): Description of lifestyle intervention. Di-abetes Care. 2002;25:2165-2171.

7. Wadden TA, Smith West D, Delahanty LM, Jakicic JM, Rejeski J,Berkowitz RI, Williamson DA, Kelley DE, Kumanyika SK, Hill JO,Tomchee CM, Look AHEAD Research Group. The Look AHEADstudy: A description of the lifestyle intervention and the evidencesupporting it. Obesity. 2006;14:737-752.

8. Centers for Disease Control and Prevention, National Center forChronic Disease Prevention and Health Promotion: Physical Activityand Health: A Report of the Surgeon General. Washington, DC: USDepartment of Health and Human Services, President’s Council onFitness and Sports; 1996.

9. Jeffrey RW, Wing RR, Sherwood NE, Tate DF. Physical activity and

weight loss: Does prescribing higher physical activity goals improveoutcome? Am J Clin Nutr. 2003;78:684-689.

72 April 2008 Suppl 1 Volume 108 Number 4

0. Delahanty LM, Nathan DM. Research navigating the course of clini-cal practice in diabetes. J Am Diet Assoc. 2004;104:1846-1853.

1. Wing RR, Hamman RF, Bray GA, Delahanty L, Edelstein SL, Hill JO,Horton ES, Hoskin MA, Kriska A, Lachin J, Mayer-Davis EJ, Pi-Sunyer X, Regensteiner JG, Venditti E, Wylie-Rosett J, DiabetesPrevention Program Research Group. Achieving weight and activitygoals among Diabetes Prevention Program lifestyle participants. ObesRes. 2004;12:1426-1434.

2. Ditschuneit HH, Fletchner-Mors M, Johnson TD, Adler G. Metabolicand weight loss effects of long-term dietary intervention in obesesubjects. Am J Clin Nutr. 1999;69:198-204.

3. Pascale RW, Wing RR, Butler BA, Mullen M, Bononi P. Effects of abehavioral weight loss program stressing calorie restrictions versuscalorie plus fat restriction in obese individuals with NIDDM or afamily history of diabetes. Diabetes Care. 1995;18:1241-1248.

4. Wylie-Rosett J, Delahanty L. An integral role of the dietitian: Impli-cations of the Diabetes Prevention Program. J Am Diet Assoc. 2002;102:1065-1068.

5. Tuomilehto J, Lindstrom J, Eriksson JG, Valle TT, Hamalainen H,Ilanne-Parikka P, Keinanen-Kiukaanniemi S, Laakso M, LouherantaA, Rastas M, Salminen V, Uusitupa M, Finnish Diabetes PreventionStudy Group. Prevention of type 2 diabetes mellitus by changes inlifestyle among subjects with impaired glucose tolerance. N EnglJ Med. 2001;34:1342-1350.

6. Hamman RF, Wing RR, Edelstein SL, Lachin JM, Bray GA, Delah-anty L, Hoskin M, Kriska AM, Mayer-Davis EJ, Pi-Sunyer X, Regen-steiner J, Venditti B, Wylie-Rosett J, for the Diabetes PreventionProgram Research Group. Effect of weight loss with lifestyle inter-vention on risk of diabetes. Diabetes Care. 2006;29:2102-2107.

7. Diabetes Prevention Program Research Group. Impact of intensivelifestyle and metformin therapy on cardiovascular disease risk factorsin the Diabetes Prevention Program. Diabetes Care. 2005;28:888-894.

8. Diabetes Prevention Program Research Group. Intensive lifestyle inter-vention or metformin on inflammation and coagulation in participantswith impaired glucose tolerance. Diabetes. 2005;54:1566-1572.

9. Seidel MC, Powell RO, Piatt GA. Translating the diabetes preventionprogram in an urban underserved community: Long term sustainabil-ity of positive clinical outcomes. Diabetes. 2007;56(suppl):A42.

0. Kramer MK, Miller R, Venditti E, Orchard TJ. Group lifestyle inter-vention for diabetes prevention in those with metabolic syndrome inprimary care practice. Diabetes. 2006;55(suppl):A517.

1. Ackermann RT, Marrero D, Honghong Z, Brizendin EJ. Translatingthe Diabetes Prevention Program into the community: The YMCAmodel. Diabetes. 2007;56(suppl):A43.

2. Ruggiero L, Rodriguez-Sanchez M, Oros S. Translating the DiabetesPrevention Program’s (DPP) lifestyle intervention to the community:Making the connection Latino pilot study. Diabetes. 2007;56(suppl):A226.

3. Janetski JH, Lisowski C. Living on the edge of diabetes: A study usingthe Diabetes Prevention Program in a community setting. Diabetes.2007;56(suppl):A229.

4. Aldana S, Barlow M, Smith R, Yanowitz F, Adams T, Loveday L,Arbuckle J, LaMonte M. The Diabetes Prevention Program: A work-site experience. AAOHN J. 2005;53:499-507; quiz 506-507.

5. Aldana S, Barlow M, Smith R, Yanowitz F, Adams T, Loveday L,Merrill RM. A worksite diabetes prevention program: Two-year im-pact on employee health. AAOHN J. 2006;54:389-395.

6. McBride PE, Einerson JA, Grant H, Sargent C, Underbakke G, Vit-cenda M, Zeller L, Stein JH. Putting the Diabetes Prevention Pro-gram into practice: A program for weight loss and cardiovascular risk

reduction for patients with metabolic syndrome or type 2 diabetesmellitus. J Nutr Aging Health. In press.