Diabetes in South Asia: Systematic Review of Risk Factors, Prevalence

This report presents a systematic review and meta-analysis of diabetes prevalence and associated risk factors in South Asia. The study investigates the trends of diabetes incidence, its prevalence in South Asian countries including India, Pakistan, Bangladesh, Nepal, Sri Lanka, Bhutan, Maldives and Afghanistan, and explores the associated risk factors, including genetic susceptibility, lifestyle factors, and urbanization. The research methodology involves a comprehensive literature search across databases like EMBASE, Cochrane Central, OVID, and MEDLINE, adhering to specific inclusion and exclusion criteria. The report aims to determine the prevalence rates, identify key risk factors, and suggest potential public health measures to address the rising diabetes burden in the region. The PRISMA flowchart is used to ensure structured reporting of the collected evidence. The findings are synthesized to provide a comprehensive understanding of the diabetes epidemic in South Asia and its implications for public health strategies. The report also mentions that the diabetes prevalence in India could show a growth of 72 per cent by the year 2030, resulting in an increase in the current prevalence rate.

Running head: DIABETES IN SOUTH ASIA
Prevalence and Analysis of Diabetes Associated Risk Factors in South Asia
Name of the Student
Name of the University
Author Note

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Undertaken Literature Search
Process of literature search:
To explore the available literature and research studies conducted in the past, a search
protocol was followed to search for relevant studies in databases using their advanced search
option. The databases, which were considered for the search of literature included EMBASE,
Cochrane Central, OVID and MEDLINE. The Medical Subject Headings (MeSH) which
were most relevant to the current research, included ‘diabetes mellitus’ and diabetes. The
MeSH subheading term was fixed to ‘Epidemiology.’ However, in addition to these MeSH
terms, the search was performed with the help of keywords relevant to the research topic.
These keywords included diabetes, prevalence, incidence rate, morbidity, mortality, South
Asia, type-2 diabetes, risk factors, India, Bhutan, Nepal, Sri Lanka, Bangladesh, Pakistan and
Maldives. The use of Boolean operators was made in the advanced search options in the
medical databases for conjuncture of keywords to increase the relevancy of the search results
to the research topic [1]. Both the Boolean operators ‘OR’ & ‘AND’ were used to make the
search, where the operator ‘AND’ was used initially to increase the count of search results
from the database and the operator ‘OR’ was used to increase the relevancy of search results,
refine and narrow down the search results. The count of search results in different databases
was high, with 6257 results in Cochrane Central, 8074 results in EMBASE, 2482 in
MEDLINE, and 2776 in Ovid.
Article selection:
The selection of relevant articles and research studies were made in compliance with
eligibility criteria. The inclusion criteria included the publishing year of the research studies
to be between 2012 and 2020, the publishing language of the journal articles to be only in
English, the age of the chosen sample population to be adults over 18 years of age, and only

2DIABETES IN SOUTH ASIA
the species of humans. Exclusion criteria stated that all studies concerned with the diabetes
prevalence in countries other than South Asian countries were excluded. The resulting pieces
of literature were screened by the analysis of the study title and abstract provided in the peer-
published journal article.
Background Literature Review
One of the major health concern globally is the increasing incidence rate of the
disease, diabetes mellitus. Diabetes mellitus is a health condition present globally and affects
individuals from all age groups. The leading indicator of diabetes in the human body is the
increase in the blood sugar levels, causing the condition of hyperglycaemia [2]. High glucose
levels in the blood are defined by the dissemination of the fasting plasma glucose in a sample
population, which is higher than the theoretical dissemination derived from epidemiological
studies that would critically minimize the risks to the health of the population. The
determined level for fasting blood glucose level is 7 mmol/L and levels higher than this
indicate the condition of hyperglycaemia [3]. In the human body, the hormone, insulin, is
known for regulating blood glucose levels and several types of diabetes have different
underlying causes for the increase in the blood glucose levels. The three primary types of
diabetes mellitus include type-1 diabetes, type-2 diabetes, and gestational diabetes [2]. In
type-1 diabetes, the insulin producing cells get destroyed, which disables the body’s
capability to regulate blood glucose level. Genetic susceptibility is thought to be the
underlying cause of type-1 diabetes mellitus. In type-2 diabetes, the cells become resistant to
insulin’s action and the pancreas is unable to meet the body’s insulin hormone demand,
leading to building up of glucose in the bloodstream. In type-2 diabetes mellitus,
environmental factors in addition to genetic susceptibility, are deemed to be the cause of
diabetes and being overweight is strongly linked to the condition of type-2 diabetes mellitus
[2]. In gestational diabetes, the female body is undergoing several hormonal changes required

3DIABETES IN SOUTH ASIA
to sustain a pregnancy. This makes the cells more resistant to the hormone insulin, leading to
a rise in the glucose levels in the blood. Diabetes is a severe health condition and a life-long
disease, and with the steep increasing incidence rates, it has become one of the major health
conditions globally. According to the World Health Organization’s 2014 report [3], the global
diabetes prevalence mellitus in 2014 was 8.5%, accounting for over 422 million individuals
globally. The numbers have increased from the global diabetes prevalence at 4.7% in 1980,
that is, over 108 million individuals, indicating a drastic increase in the incidence and
prevalence rate of diabetes. It is one of the major underlying causes of death with over 1.6
million reported deaths in the year 2016 due to the health condition of diabetes [3].
Many of the past conducted literature indicated diabetes to be epidemic but limited to
only developed countries. However, the current global reports indicate the incidence of
diabetes to be the highest in low and middle income countries [4]. The burden of diabetes is
severe in South Asian countries, which include several low and middle income countries
including India, Maldives, Bhutan, Sri Lanka, Nepal, Bangladesh, Afghanistan and Pakistan
[5]. These South Asian countries contribute to over 24% of the world’s total population, with
over 1.8 billion people. Due to lifestyle and biological factors, predisposition to the
development of diabetes in the population from South Asian countries can be observed [6].
The incidence of type-2 diabetes in South Asian countries is six time higher than the
European countries, which is a strong indicator of the growing health concern of diabetes in
South Asian countries. In addition to this, the risk of developing cardiovascular diseases in
the population from South Asia is three times higher than that of the population from
European countries, increasing the health burden among the South Asian countries [5].
Genetic susceptibility is found to be one of the major causes in addition to lifestyle factors,
which makes the population more susceptible to type-2 diabetes mellitus. According to Shah
and Kanaya [7], India, with its second largest population in the world, is one of the major

4DIABETES IN SOUTH ASIA
hubs of the diabetic population globally. The authors state that the diabetes prevalence in
India could show a growth of 72 per cent by the year 2030, resulting in an increase in the
current prevalence rate of 7.6% to an estimation of 87 million adults resulting in a 9.1%
prevalence rate by the year 2030. Such a dramatic increase in diabetes prevalence in the
South Asian inhabitants is multifactorial, as the population has shown a marked incidence of
increased resistance to insulin and visceral adiposity, genetic predisposition and impaired β-
cell function. Increased urbanization marks the increase in mental stress and decreased
physical activity levels have further contributed to diabetes prevalence [8]. Even though there
are wide-ranging reviews on diabetes in the South Asian countries, to date, there has been
only one study on the prevalence and its relevant diabetes trends, which was published in the
year 2012. The present study aims to discuss the prevalence rate of diabetes among adults
from individual South Asian nations and determine risk factors reported to be associated with
the development of diabetes in these counties.
Aim and Objectives
This paper aims to provide an all-inclusive and up-to-date systematic review of the
prevalence and meta-analysis of risk factors of diabetes in South Asia.
The research study has the following objectives:
 To determine the trends of incidence of diabetes and its prevalence in South
Asian Countries.
 To investigate the diabetes associated risk factors and perform a meta-analysis
 To suggest the potential public health measures to address the increasing
diabetes prevalence and its associated risk factors in South Asian countries.
Research Questions
 What is the trend of diabetes mellitus and its prevalence rate in South Asian
countries?

5DIABETES IN SOUTH ASIA
 What are the diabetes associated risk factors in context to its prevalence in
South Asian countries?
 What are the potential public health measures to address the prevalence and
diabetes associated risk factors in South Asian countries?
Research Design 1000
The research topic is concerned with the diabetes prevalence mellitus and risk factors
associated with the disease, limited geographically, that is, only restricted to South Asian
countries. With the help of the above mentioned search strategy, the chosen medical
databases will be searched for relevant pieces of literature. Inclusion criteria will ensure that
the research articles are peer-reviewed and are published between the years 2012 to 2020.
The stringent timeframe of the research studies will ensure the latest data available on the
prevalence rate and diabetes associated risk factors in South Asian countries. The publishing
language is limited to English only, for a global understanding of the research study and its
findings. The study design of the research studies will also influence their selection in the
review of the literature. The preferred study design is studies conducted with randomized
control trials as it provides the highest level of evidence. To measure the outcome of risk
factors, the RCT studies with odds ratio statistical analysis will be preferred. Other studies
including observational studies, will also be included for selection in the systematic review.
To eliminate the risk of bias in observational studies, the STROBE checklist will be followed
for assessment.
The two outcomes measures for the study are to estimate the diabetes prevalence and
its associated risk factors, along with risk factors summarized in the odds ratio.
The studies in the search results that did not include the diabetes prevalence in any of
the South Asian countries or presented the risk factors associated with the disease will be
excluded from further review by the researcher.

6DIABETES IN SOUTH ASIA
The primary screening of the articles by their titles and abstracts will be performed
by one researcher to collect data on the studies that are relevant to the research topic and the
researcher will review them to get estimates on the prevalence of the disease in the chosen
geographical region.
The abstract screening process is one of the most crucial aspects of the conduction of
comprehensive and high quality systematic review and meta-analyses [9]. The researcher
reviewing the abstracts will use abstract screening tools which include items such as
objective of the research, estimation of the diabetes prevalence in South Asian countries, a
summary of the associated risk factors in the term of odds ratio statistical analyses and will
use text-mining application for abstract screening.
Following the selection of articles for systematic review, synthesis of results will be
completed. The use of PRISMA (Preferred Reporting Items for Systematic Reviews and
Meta-Analyses) flowchart will ensure structured reporting of collected evidence, highlighting
the pathway of initial search results, its refinement and the final selection of articles [10]. The
PRISMA flowchart will help to present the initial numbers in search results and the final
selection post refining of the articles in context to the relevancy of the research study.

7DIABETES IN SOUTH ASIA
Figure 1: PRISMA Flow Chart depicting the Identification and selection of studies
Records identified through
MEDLINE database searching
(n = 2482)
Sc
re
en
in
g
In
cl
ud
ed
El
igi
bil
ity
Id
en
tif
ic
ati
Additional records identified
through other sources
(n = 17,107)
Records after duplicates removed
(n = )
Records screened
(n = )
Records excluded
(n = )
Full-text articles
assessed for eligibility
(n = )
Full-text articles
excluded, with reasons
(n = )
Studies included in qualitative
synthesis
(n = )
Studies included in
quantitative synthesis
(meta-analysis)
(n = )

8DIABETES IN SOUTH ASIA
Post the PRISMA flowchart that depicts the flow chart of the selection of relevant
studies, a table of characteristics for the included studies will be presented. The table of
characteristics will systematically arrange the research studies by the name of the authors
with other attributes or characteristics such as the range of years reported in the study, the age
range chosen for the diabetic population, diabetes definition, type of data reported, country of
focus (among the selected South Asian countries) and the origin of data.
This table of characteristic for included studies will be followed by another table
which will present the prevalence estimates of diabetes in the South Asian countries arrange
by the year of reporting. This table will critically help to analyse the trends in the diabetes
prevalence in South Asian countries and draw conclusive evidence on the prevalence rate.
To synthesize quantitative information from included studies, meta-analysis is used to
produce results that summarize the key findings of the research. For the particular chosen
research topic, meta-analysis of the diabetes associated risk factors in South Asian countries
and its influence on the prevalence rate in the specified regions. To measure the associated
risk factors, odds risk ratio statistics data collected from included studies will be statistically
synthesized to draw a conclusion on the probable diabetes associated risk factors and how it
affects the prevalence rate of the disease in South Asian countries. The statistical synthesis
will be ensured with the help of random effects meta-analysis model. It is the preferred model
for meta-analysis of the research studies because of the huge variation in the sample
population size. South Asian countries include India, Maldives, Pakistan, Bangladesh, Sri
Lanka, Nepal, and Bhutan, with a collective population of over 24% of the world’s total
population. Therefore, there are significant chances of heterogeneity in research studies, that
is, differences in treatment effects and other study differences. Thus, random-effects meta-
analysis is the preferred choice for statistical analysis as it takes into consideration the study
differences, sampling variability and assumes variability in the observed estimates [11].

9DIABETES IN SOUTH ASIA
The final results and research findings will be presented in the form of a forest plot.
Blobbogram, another name of the forest plot, is a graphical presentation of the estimated
research findings and results from a number of research studies that are concerned with a
single research question. The research topic for this study is to find out the diabetes
prevalence and its associated risk factors in South Asian countries. As the selection of articles
and research studies is strictly limited to be highly relevant to the research topic, the preferred
presentation of research findings should conform to the key aspects of the original question,
ensuring relativity and common aspects of prevalence and diabetes associated risk factors in
all included studies [12]. In the forest plot, all the relevant studies that are concerned with the
same research question and a common statistic can be graphically presented to readers to help
them visualize the research findings from the meta-analysis and systematic review of the
literature [13]. In the forest plot graph of research findings, the horizontal axis will plot the
odds ratio of diabetes associated risk factors in South Asian countries and the vertical axis or
the line of null effect will plot the list of authors whose research articles have been reviewed
in the study. The results of the studies will be plotted along with a 95% confidence in the
result line.
Therefore, it can be concluded that the forest plot will be the most suitable method to
synthesize the research findings and collectively present the data in graphical form for better
understanding.
Results

10DIABETES IN SOUTH ASIA
Results 1 2 3
The results and
findings from the
systematic review of
literature and meta-
analysis will most
probably support the
current literature by
providing evidence
of the increasing
incidence and
diabetes prevalence
mellitus in South
Asian countries [7].
The country India,
which has the
second largest
population in the
world, is more likely
to show the highest
growth in the
prevalence rate of
diabetes amongst the
other South Asian
countries [14]. It is
hypothesized that
increasing incidence
and diabetes
prevalence will
result in the major
economic burden of
the health care
system of the South
Asian countries, all
of which are either
low or middle
income countries
with developing
status. The health
The major diabetes
associated risk
factors in the South
Asian population
may include
psychosocial,
environmental,
lifestyle, dietary,
medical conditions
and biomarker
factors. Biomarkers
include low hip
circumference,
increased adiposity,
decreased level of
vitamin D and
adiponectin,
increased levels of
C-reactive protein,
uric acid, gamma-
glutamyl transferase
and alanine
aminotransferase
[16]. The risk factor
of unhealthy dietary
Medical conditions
might include
preterm birth,
metabolic syndrome,
gestational diabetes,
late menarche age
and high systolic
blood pressure [18].
Other risk factors of
psychosocial,
environmental and
lifestyle may include
air pollution,
smoking, low
alcohol drinking,
high sedentary time,
decreased level of
physical activity,
low level of
conscientiousness,
and education [19].

11DIABETES IN SOUTH ASIA
condition of diabetes
in South Asian
countries might be
the highest in
comparison to other
parts of the world.
Moreover, diabetes
contributes to higher
rates of
complications such
as cardiovascular
diseases and its
associated morbidity
and mortality [15].
patterns includes
low adherence to a
healthy diet,
decreased intake of
heme iron, coffee
and whole grains,
increased
consumption of
sweetened beverages
and processed meat
[17]
Ethical Issues
This research study requires no actual involvement of patients or other participants for
data collection, as the paper aims at conducting a systematic review of the literature
published in the past few years and relevant to the topic. No public or patients were involved
in the outcome measures or setting up the research question of this study. Thus, the research
study does not require to seek ethical approval from the Institutional Review Board to be
conducted. However, taking in the influential role of systematic reviews on future researches,
the research study will ensure that the selected studies are free from any ethical issues, with
the help of critical evaluation and interpretation of the research study design and other aspects
of research methods [20]. To ensure that the selected researches are free from any ethical

12DIABETES IN SOUTH ASIA
issues, the research studies will be selected based on their audience-appropriate transparency,
decisively informed selective inclusivity and informed reflexivity and subjectivity. Other
aspects, such as funding source intersect of the selected research studies, will be analysed to
eliminate any potential ethical issue and keep the findings of the systematic review of
literature reliable with high validity [21].
Timeline for Proposed Research
The proposed timeline for the systematic review of the literature to be conducted is
presented below in the form of a Gantt chart.
Activities 1st
Week
2nd
Week
3rd
Week
4th
Week
5th
Week
6th
Week
Initial Design and Searches ✓
Selection of the topic ✓
Orientation of reviews
within the literature
✓
Development of Search
Strategy
✓
Conduction of the
literature Search
✓
Assessing Eligibility of the
Studies
✓
Abstracts and Titles
Screening
✓ ✓
Screening of Full-Text
Articles
✓ ✓

13DIABETES IN SOUTH ASIA
Reference Analysis in
Included Studies
✓
Dissemination
Prepare results for
presentation
✓
Communicate research
findings
✓

14DIABETES IN SOUTH ASIA
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