Understanding epidemiological transition in India

Abstract

Background: Omran's theory explains changing disease patterns over time predominantly from infectious to chronic noncommunicable diseases (NCDs). India's epidemiological transition is characterized by dual burden of diseases. Kumar addressed low mortality and high morbidity in Kerala, which seems also to be true for India as a country in the current demographic scenario.

Methods: NSS data (1986-1987, 1995-1996, 2004) and aggregated data on causes of death provided by Registrar General India (RGI) were used to examine the structural changes in morbidity and causes of death. A zero-inflated poisson (ZIP) regression model and a beta-binomial model were used to corroborate the mounting age pattern of morbidity. Measures, namely the 25th and 75th percentiles of age-at-death and modal age-at-death, were used to examine the advances in mortality transition.

Objective: This study addressed the advances in epidemiological transition via exploring the structural changes in pattern of diseases and progress in mortality transition.

Results: The burden of NCDs has been increasing in old age without replacing the burden of communicable diseases. The manifold rise of chronic diseases in recent decades justifies the death toll and is responsible for transformation in the age pattern of morbidity. Over time, deaths have been concentrated near the modal age-at-death. Modal age-at-death increased linearly by 5 years for females (r(2)=0.9515) and males (r(2)=0.9020). Significant increase in modal age-at-death ascertained the dominance of old age mortality over the childhood/adult age mortality.

Conclusions: India experiences a dual burden of diseases associated with a remarkable transformation in the age pattern of morbidity and mortality, contemporaneous with structural changes in disease patterns. Continued progress in the pattern of diseases and mortality transition, accompanied by a linear rise in ex, unravels a compelling variation in advances found so far in epidemiological transition witnessed by the developed nations, with similar matrices for India.

Keywords: communicable diseases; disease patterns; epidemiological transition; mortality transition; noncommunicable diseases.

Fig. 1

Age pattern of prevalence rate of chronic diseases by sex and residence, India for 1986–1987, 1995–1996, and 2004.

Fig. 2

Share of major causes of death among females and males, rural India, 1975–1995: Infectious and parasitic diseases, circulatory diseases, respiratory diseases, diseases of the digestive system, injury, poisoning, and certain other external causes, such as senility.

Fig. 3

Share of major causes of death among females and males, urban India, 1972–1997: Infectious and parasitic diseases, circulatory diseases, respiratory diseases, diseases of the digestive system, injury, poisoning, and certain other external causes.

Fig. 4

Distribution of deaths attributed to communicable diseases and NCDs, by broad age groups, rural India, 1977, 1987, and 1997.

Fig. 5

Distribution of deaths attributed to communicable diseases and NCDs, by broad age groups, urban India, 1975, 1985, and 1995.

Fig. 6

Distribution of age-at-death and modal age-at-death for selected years, female and male, India, 1973–1977, 1983–1987, 1993–1997, and 2003–2007.

Fig. 7

Trends in modal age-at-death by sex and residence, India, from 1970–1974 to 2003–2007; rural female, rural male, urban female, and urban male.

Fig. 8

Trends in modal age-at-death among females and males of selected developed countries and India, including Sweden, Switzerland, the UK, France, Italy, and Japan.