EAL

MNT: Cost Effectiveness, Cost-benefit, or Economic Savings of MNT (2009)

Citation:

Herman WH, Hoerger TJ, Brandle M, Hicks K, Sorensen S, Zhang P, Hamman RF, Ackermann RT, Engelgau MM, Ratner RE, Diabetes Prevention Program Research Group. The cost-effectivness of lifestyle modification or metformin in preventing type 2 diabetes in adults with impaired glucose tolerance. Ann Intern Med. 2005; 142 (5): 323-332.

PubMed ID: 15738451

Study Design:

Cost-effectiveness analysis of DPP and UKPDS data

Class:

M - Click here for explanation of classification scheme.

Quality Rating:

POSITIVE: See Quality Criteria Checklist below.

Research Purpose:

To estimate the lifetime cost-utility (costs, health outcomes, cost-effectiveness) of the DPP interventions (lifestyle vs. metformin vs. placebo).

Inclusion Criteria:

Impaired glucose tolerance
Fasting glucose 5.27mmol to 6.94mmol per L
At least 25 years old
BMI of at least 24kg/m².

Exclusion Criteria:

Not reported.

Description of Study Protocol:

Recruitment: Not reported. Target population was members of the DPP cohort 25 years of age or older with impaired glucose tolerance.
Design: Cost-effectiveness analysis of DPP and UKPDS data.

Intervention

Placebo
Metformin
Intensive lifestyle intervention.

Statistical Analysis

Lifetime Simulation model (CDC, Markov structure) to track costs and QALYs (data from progression, costs, quality of life associated with IGT)
Base case and sensitivity analysis.

Data Collection Summary:

Timing of Measurements

The duration and follow-up were within a three-year trial period, however, in this analysis, costs were projected over a lifetime.

Dependent Variables

Cumulative incidence of diabetes, microvascular and neuropathic complications, cardiovascular complications, survival
Total direct medical and non-medical costs and health utility of IGT and type 2 diabetes
Quality-adjusted life-years (QALY)
Cost per QALY.

Independent Variables

Placebo vs. Metformin vs Intensive lifestyle intervention (DPP RCT).

Description of Actual Data Sample:

Initial N: 3,234 participants (68% female)
Age: Mean 51 years
Ethnicity: 45% minority
Anthropometrics: Mean BMI 34kg/m²
Location: DPP Coordinating & Biostatistics Centers, George Washington University, Rockville, Maryland, USA.

Summary of Results:

Variables	Lifestyle	Metformin	Placebo
Lifetime Intervention Cost ($)	9,718	8,801	2,907
Lifetime Outcome Cost ($)	42,256	46,460	48,432
Total Lifetime Direct Medical Cost ($)	51,974	55,261	51,339
Lifetime QALYs (Change re: Placebo)	10.89 (0.57)	10.45 (0.13)	10.32
Cost/Change QALY ($)	1,124	31,286

Base-Case Analysis

Compared to placebo, lifestyle and metformin interventions were estimated to delay the development of type 2 diabetes by 11 and three years, respectively and to reduce the absolute incidence of diabetes by 20% and 8%, respectively
Cumulative incidence of complications were reduced and survival improved by 0.5 and 0.2 years in the lifestyle and metformin groups, respectively
Compared to placebo, cost/QALY was approximately $1,100 and $31,300 for the lifestyle and metformin interventions, respectively. From a societal perspective, interventions cost $8,800 and $29,900/QALY, respectively.
From both perspectives, the lifestyle intervention dominated the metformin intervention.

Sensitivity Analysis

Cost-effectiveness improved when interventions were implemented as they would be in clinical practice. Lifestyle intervention was cost-effective in all age groups.
Metformin intervention did not represent good use of resources for persons older than 65 years of age.

Author Conclusion:

Compared with placebo, DPP lifestyle and metformin interventions provided substantial health benefits at an attractive cost. The lifestyle intervention, compared with the metformin intervention, provided greater health benefits at lower costs. Health policy should promote diabetes prevention to high-risk individuals.

Funding Source:

Government:

NIH. NIDDK, Office of Research on Minority, NICHD, NIA, Indian Health Service, NCRR

Industry:

Bristol Myers Squibb, Parke-Davis

Pharmaceutical/Dietary Supplement Company:

Reviewer Comments:

Authors note that simulation results depend on the accuracy of the underlying assumptions, including participant adherence.

Quality Criteria Checklist: Review Articles
Relevance Questions
	1.	Will the answer if true, have a direct bearing on the health of patients?	Yes
	1.	Will the answer if true, have a direct bearing on the health of patients?	Yes
	2.	Is the outcome or topic something that patients/clients/population groups would care about?	Yes
	2.	Is the outcome or topic something that patients/clients/population groups would care about?	Yes
	3.	Is the problem addressed in the review one that is relevant to dietetics practice?	Yes
	3.	Is the problem addressed in the review one that is relevant to dietetics practice?	Yes
	4.	Will the information, if true, require a change in practice?	Yes
	4.	Will the information, if true, require a change in practice?	Yes

Validity Questions
	1.	Was the question for the review clearly focused and appropriate?	Yes
	1.	Was the question for the review clearly focused and appropriate?	Yes
	2.	Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described?	N/A
	2.	Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described?	N/A
	3.	Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased?	Yes
	3.	Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased?	Yes
	4.	Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible?	N/A
	4.	Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible?	N/A
	5.	Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined?	Yes
	5.	Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined?	Yes
	6.	Was the outcome of interest clearly indicated? Were other potential harms and benefits considered?	Yes
	6.	Was the outcome of interest clearly indicated? Were other potential harms and benefits considered?	Yes
	7.	Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described?	Yes
	7.	Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described?	Yes
	8.	Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included?	Yes
	8.	Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included?	Yes
	9.	Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed?	Yes
	9.	Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed?	Yes
	10.	Was bias due to the review's funding or sponsorship unlikely?	Yes
	10.	Was bias due to the review's funding or sponsorship unlikely?	Yes