Critical Assessment of Type 2 Diabetes Prevention Interventions in Canada:

Finding a path through the evidence labyrinth

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Mechthild Meyer (Gentium Consulting)

Alma Estable (Gentium Consulting)

Laurie Gibbons (The Public Health Agency of Canada)

www.gentium.ca

What we hope you will take away

What works: Know evidence-based components for lifestyle interventions to prevent type 2 diabetes

An approach: A way to map out the components of these interventions

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Imagine this…Your role: Program planner (chronic disease

prevention) at a health department (HD)

Context: HD in a mid-size town, main employer: paper mill

Public Health Standard Requirement: Develop programs that are ‘evidence-based'

Chronic Disease Prevention: Reduce obesity, pre-diabetes

HD strategic goal: Decrease percentage of the adult population with pre-diabetes (obese, overweight) by 2% over the next ten years

HD target: Hard to reach adult population, especially males3

Where to start …. assessing the effectiveness of interventionsLifestyle and environmental

interventions resulting in lasting behavioural change

You heard that most focus on reducing weight or preventing weight gain through

Physical activityDietary behaviour

Hunch/Myth or evidence?

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Looks familiar?

Assessing the effectiveness of type 2 diabetes interventions

Systematic Reviews, Syntheses

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Multiple combinations

of intervention components

What part of the

intervention makes it effective?

What does the evidence say?Evidence contradictory and limited: Lifestyle interventions are as effective as

pharmaceutical interventions to reduce the rate of progression to type 2 diabetes

Effective components:

• Intensive low-fat diets + exercise + counselling

• “Mediterranean” diet combined with behaviour therapy

Types of effective lifestyle interventions are:

• Sustained, long-term, intensive, multicomponent

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What does the evidence say?Diet-only interventions

Exercise-only interventions

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• Some reduce weight

• Long-term follow-up: no evidence in diabetes risk reduction

Increase physical activity, e.g., walking

Limited evidence: changes last

Insufficient evidence: reduce risk factors for diabetes

Combined interventions• Evidence: Diet + Exercise + psych. support

reduce incidence of type 2 diabetes in high risk groups (pre-diabetes or metabolic syndrome)

Intervention Components

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Multiple Intervention Components

Education

Counselling

Diet Modification

Physical Activity Modification

DevicesEnvironment, policy change

What is an Intervention?

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What: components (i.e., diet, PA)

Interventions are complex with many different components

Approach: activities (i.e., course, counselling) How: delivery (i.e., online, in person)

Who: intermediaries (e.g., teacher, dietician)

Where: setting (e.g., school, workplace)Timing: length (e.g., 3-months, follow-up)

Interventions may include a variety of components

What (content)

Nutrition: reduced overall calories

Nutrition: reduced fats

Nutrition: increase in

fibre

Nutrition: increase in F&V intake

Physical Activity: reduced

screen time

PA: increased level of PA

PA: increased walking

Approach (activity)

Advice, prescription

Counselling ortherapy

Support (peer, family, work crew)

Program sessions, course,

curricula, structured

Environmental changes,

policies

Incentives (monetary, time, value

driven)

Media campaign,

communication

How (medium)

Devices (pedometers, prepared

foods)

Individual (one-on-one)

In groups, supervised

Print material, info. in writing

Telephone

Internet, web-based, email, SM,

apps

In groups, unsupervise

d

Who (intermediari

es)

Professional (i.e. health,

teacher, trainer)

Para-professional,

peer

Family, parent, friend

Researcher

Self-managed

Policy makers

Where (site)

Home

Community, neighbourho

od

Population-wide

School, daycare

Clinical setting, hospital

Workplace

Research institute

Timing (length,

frequency)

Once

Regularly, over a

specific time frame

Ongoing, sustained

With follow-up

No follow-up

One to 12 years

Unspecified

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Example: POWER - Preventing Obesity Without Eating like a Rabbit (Australia)

What: change in nutrition, physical activityWhere: Workplace, target: overweight, obese,

male, blue collar shift workersApproach: One educational information session

(behaviour change strategie, monetary incentives)

How: Weight loss handbook, pedometerWebsite: online support

Self-weighing each week

Email feedback by professionals

Who: Delivered by trained staffTiming: 14 weeks with follow-up

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POWER - Evidence (outcomes)

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After 14 weeks participants had lost significantly more weight (on average 4.3 kg), about 5% of their baseline weight, than controls

Significant effects on waist circumference, BMI, systolic blood pressure, resting heart rate and physical activity.

Only 28% of men in the intervention group used the online component of the intervention, but those who did lost most weight

Source: Morgan et al. (2011). Efficacy of a workplace-based weight loss program for overweight male shift workers: the Workplace POWER (Preventing Obesity Without Eating like a Rabbit) randomized controlled trial. Prev Med, 52(5), 317-325.

Example: POWERWhat

(content)

Nutrition: reduced overall calories

Nutrition: reduced fats

Nutrition: increase in

fibre

Nutrition: increase in F&V intake

Physical Activity: reduced

screen time

PA: increased level of PA

PA: increased walking

Approach (activity)

Advice, prescription

Counselling or Therapy

Support (peer, family, work crew)

Program sessions, course,

curricula, structured

Environmental changes,

policies

Incentives (monetary, time, value

driven)

Media campaign,

communication

How (medium)

Devices (pedometers, prepared

foods)

Individual (one-on-one)

In groups, supervised

Print material,

info.in writing

Telephone

Internet, web-based, email, SM,

apps

In groups, unsupervise

d

Who (intermediari

es)

Professional (i.e. health,

teacher, trainer)

Para-professional,

peer

Family, parent, friend

Researcher

Policy makers

Self-managed

Where (setting)

Home

Community, neighbourho

od

Population-wide

School, daycare

Clinical setting, hospital

Workplace

Research institute

Timing (length,

frequency)

Once

Regularly, over a

specific time frame

Ongoing, sustained

With follow-up

No follow-up

One to 12 years

Unspecified

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Example: POWER

What

(content)Nutritio

n: reduced overall caloriesNutritio

n: increas

e in F&V

intakePA: increased level

of PAPA:

increased

walking

Approach

(activity)

Support (peer, work crew)

Program

session

Incentives

(monetary)

How (medium

)

Devices (pedomet

er)

Print material

Web-based, email

In groups,

unsupervised

Who (intermedia

ries)

Professional

Self-managed

Where (setting)

Workplace

Timing (length,

frequency)

Regularly, 14-weeks

With follow-

up

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Conclusions

Mapping out intervention components may make it easier to know what combination lead to the ‘evidence’ (desired outcomes)

Knowing the components facilitates program planning

Program planners can be more confident that their program is evidence-based

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Thanks!For more information:

Mechthild Meyer: meyer@gentium.caAlma Estable: estable@gentium.caLaurie Gibbons: laurie.gibbons@phac-aspc.gc.ca

Gentium Consulting: www.gentium.ca The Public Health Agency of Canada

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