Epidemiologic Transition and Spread of Non-Communicable Disease

Master of Public Health
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Epidemiologic transition and spread of non-communicable disease: Noncommunicable
disease (NCD) is also termed as chronic disease which persist for the longer duration. NCDs
mainly occurs due to multiple factors like genetic, physiological, environmental and
behavioural factors. NCDs mainly occur in the low and middle socio-economic countries and
globally approximately 70 % deaths occur due to NCDs. Approximately, 85 % deaths of
NCDs occur in low and middle socio-economic countries. NCDs are categorised into
different types like cardiovascular, cancers, diabetes and respiratory diseases. Cardiovascular
disease includes heart attack and stroke. Respiratory diseases include chronic obstructive
pulmonary disease and asthma. Most of deaths of NCDs occur due to cardiovascular diseases
with approximately 18 million people annually die due to cardiovascular disease followed by
cancers, respiratory disease and diabetes deaths occur in 9, 3.9 and 1.6 million people
respectively. Population of developing countries are misfortunate due to multiple factors like
poverty, malnutrition, infectious diseases and diseases related to pregnancy and childbirth
(Rodriguez-Fernandez et al., 2016). In developing countries, in the last of 12 years;
traditional diseases reduced from 49 to 38 % and NSDs increased from 40 to 51 %. This
burden of disease estimated in terms of disability-adjusted life years relative to all causes of
disease. In developing countries, number of deaths are proportional to the burden of disease.
Number of deaths due to the traditional diseases reduced from 37 to 27 % and number of
deaths due to NCDs increased from 53 to 63 %. In developing countries, disease burden is
3.5 times higher and deaths are 2.5 % higher for NCDs as compared to the western countries.
Rapid rise in NCDs occur in developing countries; however, it remains stable in the western
countries (Min et al., 2018; Siegel et al., 2016).
Increase in the global burden and diverse pattern of NCDs in the different geographical
regions are helpful in demonstrating epidemiologic transition. During the past two centuries,
it has been observed that there is dramatic shift in the death due to infectious disease and
malnutrition to the cardiovascular disease and cancer in the both developed and developing
countries. However, rate of shift is at faster rate in the developing countries as compared
developed countries. Between 1999 to 2020; there was increase in the prevalence of
cardiovascular diseases by 120 and 137 % in women and men respectively (Rodriguez-
Fernandez et al., 2016; Min et al., 2018).
Risk factors: Tobacco is one of the major factors for the occurrence of NCDs in developing
countries. Modifiable risk factors can be controlled through intervention and probability of
disease occurrence can be effectively reduced. WHO recommended four modifiable risk
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factors for NCDs like physical activity, tobacco use, alcohol use and unhealthy diet in the
form of high fat and sodium intake with low fruit and vegetable intake. Non-modifiable risk
factors can not be controlled through intervention. These risk factors include age, gender,
race and family history (Esmailnasab, Moradi, and Delaveri, 2012). Tobacco use is
responsible for the prevalence of cardiovascular disease, diabetes, cancer and chronic
respiratory disease in countries like India. Unhealthy diet, physical activity and harmful use
of alcohol are mainly responsible for the occurrence of cardiovascular disease, diabetes and
cancer. Modifiable risk factors lead to metabolic risk factors which are the biochemical
processes responsible for the body’s normal functioning. WHO prioritised four metabolic risk
factors for NCDs which include increased blood pressure, increased total cholesterol level,
raised glucose level and overweight and obesity (Nethan, Sinha, and Mehrotra, 2017).
Environmental risk factors are the major cause of NCDs in the developing world. Household
and outdoor pollution are the major environmental risk factors responsible for the occurrence
of NCDs. Environmental risk factors can be of different types like physical, chemical,
biological and work related. These environmental factors can be modifiable; however, natural
environmental factors can not be modifiable. Approximately 90 % population of the
developing countries are exposed to harmful pollution levels in the ambient air and 40 %
population in developing countries exposed to harmful smoke due to cooking with inefficient
technology and fuel combinations. Stroke, ischaemic heart disease, lung cancer and chronic
obstructive respiratory disease occur in 24, 25, 28 and 43 % respectively population of
developing countries like Republic of Korea, Cubatao and Brazil due to exposure to ambient
and household air pollution. Workplace related exposure of chemicals and chemical mixtures
are responsible for approximately 1.3 million deaths annually in the form of cardiovascular
diseases, chronic obstructive pulmonary disease, and cancers. Chemical exposure also leads
to neurological and mental disorders (Nelson, Nyarko, and Binka 2015; Norman et al., 2015).
Determinants: Social determinants are responsible for the distribution of risk factors of
NCDs. Social inequalities before birth and in the early life are responsible for the lifetime
NCDs. Child development is associated with social gradients in terms of physical, cognitive
and emotional/behavioural aspects. Disadvantaged socioeconomic status is mainly
responsible for the improper brain development which contribute to the improper regulation
and control of behaviour and thought process which produces risk factors of NCDs. These
risk factors include loss of cognitive control over diet and physical activity. Family
environment is mainly responsible for the occurrence of obesity and overweight. Low and
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