Ebph.it
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
A systematic review of the
cost-effectiveness of lifestyle
modification as primary prevention
intervention for diabetes mellitus type 2
Katrin I. Radl(1), Carolina Ianuale(2), Stefania Boccia(2)
Background: diabetes is one of the leading causes of death, and has a huge economic impact on
the burden of society. Lifestyle interventions such as diet, physical activity and weight reducing are
proven to be effective in the prevention of diabetes. To encourage policy actions, data on the cost-
effectiveness of such strategies of prevention programmes are needed.
MeThods: a systematic review of the literature on the cost-effectiveness of prevention strategies
focusing on lifestyle interventions for diabetes type 2 patients. a weighted version of drummond
checklist was used to further assess the quality of the included studies.
resuLTs: six studies met the inclusion criteria and were therefore considered in this paper. Intensive
lifestyle intervention to prevent diabetes type 2 is cost-effective in comparison to other interventions.
all studies were judged of medium-to-high quality.
concLusIons: policy makers should consider the adoption of a prevention strategy focusing on
intensive lifestyle changes because they are proven to be either cost-saving or cost-effective.
Key words: Diabetes; Prevention; Cost-effectiveness; Lifestyle
(1) SDA Bocconi School of Management, Milan, Italy
Corresponding author: Katrin Radl, Gletscherblick
(2) Institute of Hygiene, Università Cattolica del Sacro
30b, 6080 Igls, Austria. Tel: 0043 676 3302 448.
Cuore, Rome, Italy
the literature shows strong evidence that evitable risk factors like overweight and lack
Diabetes mellitus is one of the top ten
of physical activity are the main determining,
causes of death for both low and high-
non-genetic factors of DMT2 [3-7]. The
income countries [1]. An interaction of genetic
worldwide increase of the prevalence of
predisposition along with behavioural and
diabetes mellitus type 2, and the importance
environmental risk factor was found to be a
of obesity and lack of physical activity, as
reason for diabetes mellitus type 2 (DMT2)
stated by the WHO [8] increase the need of
[2]. Even though it is not yet known what
prevention strategies and policy implications
role genetics play in occurrence of diabetes,
to be taken. Caring for diabetes and the
coSt-effectiveneSS of lifeStyle modification for dmt2
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
subsequent complications is expensive [9],
Quality Adjusted Life Years (QALYs) gained
however some interventions have the ability
or as Life Years Gained (LYGs); original
to reduce the burden of the disease. One
publication language was English; published
possible primary prevention strategy relies
between January 2007 and February 2012;
on lifestyle modification i.e., changed dietary
diabetes type 2. Studies were excluded if
habits, increased physical activity, maintaining
the lifestyle intervention was combined with
or reducing body weight. In the last years
therapy, or if they were compared with
several randomised, controlled clinical trials
treatments such as gastric bypass surgery or
have investigated the impact of changing diet
therapeutic or enteral nutrition.
and physical activity on the prevention of type 2 diabetes. The Finnish Diabetes Prevention Study (DPS) as well as many other studies
reporting of results
[10-12], demonstrated a clinically significant impact of lifestyle changes in the decrease of
In order to make ICERs (Incremental
diabetes. However, resources are scarce and it
Cost-Effectiveness Ratio) within the different
is important to review if the adoption of such
studies comparable, all costs were converted
a prevention strategy is cost-effective. The aim
into 2012 Euro using the OANDA Currency
of this study is to systematically review the
Exchange Calculator [14] for yearly average
existing English literature available from 2007
annual exchange rates. Costs already expressed
to 2012 on the cost-effectiveness of lifestyle
in Euro (€) were also adjusted to 2012 by using
changes as a primary prevention intervention
the Italian Consumer Price Index [15]. ICERs
for diabetes mellitus.
are then presented in €/QALY or €/LYG and rounded to the nearest hundred Euro.
For the classification of the intervention a
research desIgn and MeThods
threshold approach was used, assuming that an intervention is cost-effective if the ICER is
This systematic review was performed
lower than € 20 000-30 000 and cost saving if
following the PRISMA statement [13]. Studies
the costs are lower and health outcomes are
were identified by searching NCBI's PubMed
better than in the compared intervention.
database and SCOPUS database. Following
Results from the included studies are
keywords were used to search the database
summarised giving an overview of the study
for appropriate literature indicating diabetes:
population, the intervention, the comparison,
diabetes OR diabetes mellitus OR diabetes
where effectiveness data was drawn from, the
AND mellitus OR diabetes insipidus OR
analytical horizon, the study perspective and
diabetes AND insipidus; indicating cost-
the classification of the intervention using the
effectiveness: cost-benefit analysis OR cost-
criteria described earlier.
benefit AND analysis OR cost-effectiveness OR cost AND effectiveness; indicating prevention: prevention AND control OR prevention
OR prevention and control OR prevention; indicating lifestyle: life AND style OR lifestyle
A weighted version of Drummond checklist
OR life style.
was used to further evaluate the quality of the studies included in the systematic review [16, 17]. The checklist was developed to assess the
Inclusion and exclusion criteria
quality of an economic evaluation considering the following sections: study design, data
Criteria for inclusion in the review were the
collection, analysis and interpretation of results.
following: original cost-effectiveness analysis
All of the 35 items were explored by two
or other full economic analysis; primary
independent reviewers for included study. The
intervention by changing lifestyle (e.g. by diet
weighted version assigned a maximum global
and/or physical activity); prevention strategy
score of 26 for study design, of 45 for data
for diabetes type 2 patients; pharmacotherapy
collection, of 48 for analysis and interpretation
or no intervention was a comparator to lifestyle
of results section, while the global highest
intervention; outcomes were presented as
available score was 119.
coSt-effectiveneSS of lifeStyle modification for dmt2
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
Study (DPS) [20]. By developing a Markov model with seven states over a lifetime horizon
Following this search strategy, 128 studies
they estimated that prevention strategies based
were found in the PubMed database and 139
on lifestyle interventions could be cost-effective
in SCOPUS database. All studies were then
from the societal perspective but depended
exported into EndNote. After exclusion of
on sex, age group and threshold values.
papers published before 2007, 145 abstracts
However the results of the two studies were
remained for screening. Six studies were
quite different. The study result of 2007 [18]
identified as being eligible for this review
was that in borderline groups the cost/QALY
meeting the inclusion criteria. Most of the
was € 47/QALY for females and € 228/QALY
papers were excluded because they were either
for males. In the study conducted only one
not related to diabetes or did not provide the
year later [19], the ICERs were much higher,
right outcome data (€/QALY or €/LYG) (Figure
coming up to € 3 200/QALY for females and
1 for the Flow Diagram). A summary of the
€ 1 600/QALY for males at the age of 30 with
studies included in this systematic review can
overweight. The difference might result from
be found in Table 1.
the different population and age considered in
Two studies by Galani et al. [18, 19] focusing
the result, but this still has to be considered
on lifestyle intervention were conducted on
when interpreting the results.
both obese and overweighed population
Icks et al. [21] investigated the cost-
groups in Switzerland. Effectiveness data was
effectiveness of the Diabetes Prevention
taken from the Finnish Diabetes Prevention
Program (DPP) in a real-world setting in
ThE sEaRch sTRaTEGy and Flow dIaGRam FoR daTabasEs sEaRch
coSt-effectiveneSS of lifeStyle modification for dmt2
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
Germany, getting their effectiveness data
patient participation to achieve better clinical
both from the DPS and literature review.
and cost-effectiveness, because acceptance of
They conclude that even though the lifestyle
and adherence to the intervention is low
intervention program was more cost effective
and the drop- out rate is high. ICERs were
than metformin, before implementing such a
calculated from the societal and healthcare
strategy efforts should be made to improve
perspective and were reported as € 31 000/
dEscRIpTIon oF ThE cosT-EFFEcTIvEnEss sTUdIEs FoR dIabETEs pREvEnTIon
yEaR, InTERvEnTIon compaRIson
modEl classIFIcaTIon
dIscoUnT analysIs
€200/QALY 2006, 3% Probabilistic DAM Cost-effective
€1 600/QALY 2006, 3% Probabilistic DAM Cost-effective
years old and overweighted
[18], 2007, intervention
€10 900/LYG; 2000; 3% Univariate DAM Cost-effective
[20], 2012, intervention
2012; 3% Probabilistic
older age groups
Probabilistic Markov
coSt-effectiveneSS of lifeStyle modification for dmt2
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
QUalITy oF InclUdEd sTUdIEs
REFEREE's chEcklIsT
(1) The research question is stated
(2) The economic importance of the research
question is stated
(3) The viewpoint(s) of the analysis are clearly
stated and justified
(4) The rationale for choosing the alternative
programmes or interventions compared is stated
(5) The alternatives being compared are clearly
(6) The form of economic evaluation used is stated
(7) The choice of form of economic evaluation is
justified in relation to the questions addressed
(8) The source(s) of effectiveness estimates used
(9) Details of the design and results of
effectiveness study are given (if based on a
single study)(10) Details of the method of synthesis or meta-
analysis of estimates are given (overview)
(11) The primary outcome measure(s) for the
economic evaluation are clearly stated
(12) Methods to value health states and other
benefits are stated
(13) Details of the subjects from whom
valuations were obtained are given
(14) Productivity changes (if included) are
reported separately
(15) The relevance of productivity changes to the
study question is discussed
(16) Quantities of resources are reported
separately from their unit costs
(17) Methods for the estimation of quantities
and unit costs are described
(18) Currency and price data are recorded
(19) Details of currency of price adjustments for
inflation or currency conversion are given
(20) Details of any model used are given
(21) The choice of model used and the key
parameters on which it is based are justified
(22) Time horizon of costs and benefits is stated
(23) The discount rate(s) is stated
(24) The choice of rate(s) is justified
(25) An explanation is given if costs or benefits
are not discounted
(26) Details of statistical tests and confidence
intervals are given for stochastic data
(27) The approach to sensitivity analysis is given
(28) The choice of variables for sensitivity
analysis is justified
(29) The ranges over which the variables are
varied are stated
(30) Relevant alternatives are compared
(31) Incremental analysis is reported
(32) Major outcomes are presented in a
disaggregated as well as aggregated form
(33) The answer to the study question is given
(34) Conclusions follow from the data reported
(35) Conclusions are accompanied by the
appropriate caveats
Y=yes; N=not; NC=not clear; NA=not appropriate
coSt-effectiveneSS of lifeStyle modification for dmt2
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
QALY and € 5 400/QALY respectively.
(item 27), the choice of variables for sensitivity
In order to assess the economic
analysis is justified (item 28); moreover all the
consequences of a DPS intervention in Sweden,
studies compared relevant alternatives (item
Lindgren et al. [22] created a simulation model,
30), reported incremental analysis (item 31),
using effectiveness data from the DPS and cost
answer to the study questions (item 33) and
data from Swedish studies. Besides showing
conclusions (item 34). Most studies stated
that such a program would be both cost-saving
research question (item 1) and the viewpoint of
from the healthcare perspective and cost-
analysis (item 3), justified the form of economic
effective form a societal perspective, they also
evaluation (item 7), stated the primary outcome
prognosticated an increase of survival and the
measure of economic evaluation (item 11),
cost associated with it. ICERs were € 10 900/
described methods for quantities and estimation
LYG and € 156 000/LYG, respectively.
of unit costs (item 17) and details of any model
A four-state Markov model was used by
used (item 20), justified the choice of model
Neumann et al. [23] with data on transition
used (item 21), stated the range over which
probabilities from best available evidence,
variables are varied (item 29), gave appropriate
calculating costs from the perspective of society.
conclusions (item 35). Details of the study
Their results show that diabetes prevention
design were not clearly given by Neumann
intervention can be cost-effective, but the outcome
and al. [23], Galani and al. [18] and Galani
is very uncertain and depending on different
and al. [19]. Finally some deficiencies have
factors, such as age. QALYs gained through
been highlighted referring to analysis and
this strategy were low, but the ICER showed
interpretation of results section. According to
cost-effectiveness if initiation of the intervention
the weighted Drummond's scale, the median
was at an age of 70 years. For men and women
quality score of selected studies was 93, with
between 30 and 50 years the adoption of the
a minimum score of 77, and a maximum score
intervention leads to a saving in costs.
of 105 (Table 2). In study design question two
In order to assess the cost effectiveness
studies attained the maximum available score,
of the DPP, the Diabetes Prevention Program
no maximum available score was attained
Research Group [24] performed an economic
in data collection section and analysis and
evaluation both from the health care and societal
interpretation of results.
perspective using prospectively collected data on resource utilisation, cost and quality of life. Throughout their study they approved
the cost-effectiveness of lifestyle intervention over metformin and the cost-saving compared
Several studies such as the US DPP [25],
to placebo. They reported € 19 400/QALY for
the Finnish DPS [11] and the Indian DPP [26]
females and € 27 600/QALY for males for a
have already presented the efficacy of lifestyle
population aged 70 years.
modification. Our systematic review showed that lifestyle modification as a prevention strategy is not only efficient but it is also cost
Quality of characteristics included in the study
effective and/or in some cases cost saving. If the
and quality of the included studies
costs of such an intervention could be further reduced, cost-effectiveness would increase. A
Table 2 reports qualitative evaluation
possible first step in this direction could be the
assigned to each included study, according
changing of the setting where the intervention
to the 35 items exploring study design, data
was provided. But also the different methods
collection and analysis and interpretation of
available (information delivery about lifestyle
results. All the studies clearly defined the
modifications in groups or on a one-by-one
economic importance of research question
basis) should be evaluated and improved.
(item 2), the form of economic evaluation (item
However our study has several limitations:
6), the sources of effectiveness estimates (item
first, we included only English-language
8); in all the studies quantities of resources are
publications; second, most of these studies rely
reported separately from their unit costs (item
on different methodologies, include varying
16), currency and prices data are reported (item
types of costs, have different outcomes or
18), the approach to sensitivity analysis is given
measure outcomes differently and have a related
coSt-effectiveneSS of lifeStyle modification for dmt2
epidemiology Biostatistics and public Health - 2013, volume 10, number 2
SyStematic reviewS and meta- and pooled analySeS
baseline risk which makes the comparison
when evaluating the cost-effectiveness.
difficult. Also the country setting can influence
Furthermore it would be advantageous to
the outcomes. Another issue that should be
have information about the cost-effectiveness of
considered is that different healthcare systems,
changes in public policies or public insurance
population groups and values, clinical practices,
incentives to physician, may have an impact on
Eventually the impact of multiple different
interventions should be evaluated as well,
We considered a threshold approach for the
because in a real-world setting patients follow
classification of the cost-effectiveness, however
more than one intervention at the same time.
setting a threshold is controversial. Since the
It is important to keep in mind that
UK [27], the USA [28] and Australians [29] all
cost-effectiveness should not replace decision
use different thresholds, the WHO recommends
makers, but should inform them to help them
basing the decision on the country's GDP [30].
making their decision. Cost-effectiveness is
An intervention is considered as cost-effective
not the only aspect to consider when deciding
if the costs per DALYs are 1.3 GDP per capita.
whether or not to adapt an intervention,
Five of the six studies used economic decision
because CEAs (Cost-Effectiveness Acceptability)
models to evaluate the costs, thus providing
do not take into account the benefits, utility,
information at a much lower level than trials
willingness to pay (both from a personal
in a real world setting. But even with the help
and a societal perspective), or any social,
of Decision Modelling not all costs, values and
legal or ethical issues that may occur when
criteria that are relevant for decision makers
adapting the intervention. Although the six
can be captured. Furthermore they are based
studies included in the systematic review are
on assumptions and may not represent the
of good quality, some deficiencies have been
reality due to oversimplification. However DAMs
documented in all the sections. Future studies
(Decision Analysis Model) have the ability to
will need to take better account of the items
help to inform policy makers. In the future
related to study design, data collection and
economic evaluation of diabetes intervention
results from a methodological point of view.
should address the impact in real-world settings,
This is also necessary to perform comparable
because non-compliance, drop-out rates or
and scientifically based economic evaluations.
attrition rates are very often not considered
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Source: http://ebph.it/article/viewFile/8846/8037
TROOP 505 OVER THE COUNTER (OTC) MEDICATION AUTHORIZATION This form authorizes registered adult leaders of Troop 505 of Naperville Illinois to dispense "over the counter" (non-prescription) medications to scouts under their supervision if in their judgment it is appropriate. Execution of this form is voluntary; however, under BSA policy, adult leaders are prohibited from
Oriental Pharmacy and Experimental Medicine 2008 8(1), 24-31 Investigation into the mechanism of action of Moringa oleifera for its anti-asthmatic activity Anita Mehta* and Babita Agrawal Department of Pharmacology, L.M. College of Pharmacy, Ahmedabad - 3800009, India In the present investigation, we studied the effect of alcoholic extract of Moringa oleifera (M.oleifera) seed kernels on various experimental models of bronchial asthma. Significant (P < 0. 05)increase in preconvulsion time was observed due to pretreatment with M. oleifera when theguinea pigs were exposed to either acetylcholine (Ach) or histamine aerosol. This bronchodilatingeffect of M. oleifera was comparable to ketotifen fumarate. Spasmolytic effect of M. oleifera was alsoobserved by dose dependent inhibition of ideal contractions induced by Ach, 5HT, histamine andBaCl2. Alcoholic extract of M. oleifera produced significant dose dependent protection by eggalbumin and compound 48/80 induced mast cell degranulation. Pretreatment with alcoholicextract of M. oleifera also decreased carrageenan induced rat paw edema, which was comparableto that of standard diclofenac sodium. Minimum inhibitory concentration for alcoholic extract ofM. oleifera was low as compared to cold-water extract and hot water extract when antimicrobialactivity was tested against various respiratory pathogens like Escherichia coli (E. coli), Staphylococusaureus (S. aureus) and pseudomonas aeruginosa (P. aeruginosa). Our data suggest that antiasthmaticactivity of M. oleifera seed kernels may be due to its bronchodilator, anti-inflammatory, mast cellstabilization and antimicrobial activity.