分子薬学および有機プロセス研究ジャーナル

抽象的な

Transition of Intervention of Clinical Trials for Obesity

 Sato H,

 ABSTRACT
Objectives: Earlier studies have revealed that
modification of lifestyle habits from the aspects of
nutrition and exercise is the most effective measure to
control metabolic syndrome, and this finding may be
reflected in the number of registered clinical trials.
This paper aims to test this assumption and conduct
exploratory analysis of the recent trends in clinical
trials related to obesity.
Design and methods: Of the clinical trial data
registered with the International Clinical Trial
Registry Platform (ICTRP), we used 1,478 data sets of
obese patients for analysis (available as of August
2016). This study is exploratory analysis, aiming to
test some hypotheses and identify the overall
tendency. The target hypotheses are as follows.
Among clinical trials targeting obese patients, the
amount of these intended to verify the effect of
lifestyle modification has been increasing year by
year. Results: the share of clinical trials targeting
obesity has been increasing year by year. We clearly
found that the amount of clinical trials using lifestyle
intervention has been increasing .
In the study conducted by Knowler in 2002, the
research team divided obese patients with BMI25 or
higher into three groups, i.e., those given a placebo,
those treated with metformin, and those instructed to
modify their lifestyle, and observed their conditions
over four years. The research team found that the
cumulative incidence of diabetes was statistically
significantly lower among the lifestyle modification
group than among the metformin group. Following a
number of similar study results, more importance has
been given to lifestyle modification than to treatment
with mediation as a strategy to control obesity, or
metabolic syndrome. Leading the planet during this
area, Japan introduced a system of specified medical
checkups and specified medical guidance in 2008.
Under this technique , people receiving medical
checkups undergo measurement of their waist
circumference, BMI, then forth. The system is
designed to thereby find people who are at risk of
lifestylerelated diseases due to high blood sugar, high
blood pressure, and lipid abnormality, from among
those whose measurement results exceed the standard
ranges. These people are given health guidance to
switch their lifestyle habits. Other countries followed
Japan, starting to implement government-led measures to
modify people’s lifestyle habits including diet and
exercise. Backed up by a number of study results such as
those obtained by Sacks and Eyles , the first bill in the
United States to levy tax on soda and other sugarsweetened
beverages was passed by the council of the
City of Berkeley, California . A similar soda tax is also
scheduled to be introduced in the City of Philadelphia .
This trend has the potential of spreading across the
United States.
Thus, earlier studies have revealed that modification
of lifestyle habits from the aspects of nutrition and
exercise is the most effective measure to control
metabolic syndrome, and this finding may be reflected in
the number of registered clinical trials. Presumably,
among clinical trials targeting obese patients, while the
amount of trials using surgery and drugs has been
relatively decreasing year by year, the amount of these
intended to verify the effect of lifestyle modification has
been relatively increasing year by year. This paper aims
to test this assumption and conduct exploratory analysis
of the recent trends in clinical trials related to obesity
In the Advanced search of ICTRP [7], when inputting
the disease name in the condition column, data of the
corresponding clinical trial is output. In this study, we
entered “obesity” within the condition field of Advanced
search and analyzed the info of all clinical trials output.
Of the clinical trial data registered with the International
Clinical Trial Registry Platform (ICTRP) [8], we used
1,478 data sets of obese patients for analysis (all from
database inception to August 19, 2016)
In order to analyze these hypotheses, we extracted
data regarding Date Registration, Study Type, Gender,
Minimum Age, Maximum Age, and Phase, from the
1,478 data sets mentioned above. We also read data
regarding interventions one by one and classified the
data into five categories, i.e. Surgery, Device,
Supplement, Lifestyle Habits, and Other. An
intervention that may fall within more than one category,
such as modification of lifestyle habits after surgery, is
classified as “Surgery.” Other interventions that may fall
within more than one category are classified into the
category of more invasive intervention. “Device” covers
a good range, including implantable devices,
communication devices for remote medical aid , and
even video games. “Supplement” mainly includes
vitamin tablets and plant extracts. As “Lifestyle Habits,” we selected nutrition and exercise as well as education
on these as the major types of interventions. Other
interventions that cannot be assigned to one of these
categories, such as acupuncture and moxibustion
therapy, music therapy, and survey, are classified into
“Other.”
The percentage of clinical trials targeting obesity
has been increasing year by year. This trend is clear
from the residuals adjusted for degrees of freedom.
While all residuals in clinical trials targeting obesity
conducted years ago take negative values, all residuals
in recent clinical trials take positive values. Table 2
shows the yearly trends of interventions used in
clinical trials targeting obese patients. Looking at the
residuals adjusted for degrees of freedom after
conducting a chi-squared test, we clearly found that
the number of clinical trials using lifestyle
intervention has been increasing
Keywords: Obesity; Metabolic syndrome; Clinical
trials