India’s battle with affluence and poverty

A billion-plus population with unequal distribution of wealth is stretching India’s health system two ways, research has revealed.

Rising affluence in some quarters is adding obesity, diabetes and cardiovascular diseases to the long-term burden of gut and lower respiratory tract infections that usually afflict the poor.

This paradoxical mix of diseases reflects an ongoing epidemiologic transition, which has emerged alongside the transition from a low-income to middle-income economy, researchers say.

In a paper published in the journal JAMA Open Network, epidemiologists Daniel Corsi from the University of Ottawa in Canada and SV Subramanian from the US-based Harvard TH Chan School of Public Health provide a picture of how India’s economic transition is shaping the burden of disease.

Analysing data from the fourth Indian National Family Health Survey, an exercise that measured the height, weight, blood pressure and random blood glucose levels of women aged 15 to 49 and men 15 to 54, the pair found a clear link between socio-economic status (SES) markers such as household wealth, education and social caste and the risks of obesity, diabetes and high blood pressure. 

Among the SES markers, household wealth could be positively linked to all three conditions. The prevalence of diabetes varied from 1.5% among the poorest households to 4.5% among the richest.  High blood pressure ranged between 11% and 17.1% on the same measure. Obesity ranged 1.7% to 18.6%. 

Education was found to play a marginal role in obesity, with prevalence increasing from 7% among those with no schooling to 13% among the college educated. Wealth and obesity were robustly correlated.

Obesity, diabetes and high blood pressure are the major risk factors that predispose people to cardiovascular diseases.

“The study can help quantify how such risk factors for cardiovascular disease are distributed across different socio-economic groups in India,” says Corsi. “It can help devise plans to target vulnerable people in specific regions where resources may be most appropriately allocated.”   

There are a variety of potential mechanisms through which wealth status may be linked to obesity and diabetes, Corsi explains.

Wealth might bring about changes in lifestyle, such as reduced physical activity or a switch from agricultural to more sedentary occupation. Movement into urban areas and the resulting easy availability of processed and nutrient-rich food are potential triggers for obesity.

Corsi and Subramanian note that members of low-status castes and tribes had lower levels of diabetes, high blood pressure, and obesity compared to other social groups.  However, they were also at greater risk for communicable diseases which may arise through sub-optimal nutritional status, compromised immune systems, and poor hygiene.

A separate study conducted in 2016 among children under the age of five belonging to the Sugali tribes living in urban areas in the state of Andhra Pradesh found that malnutrition, diarrhoea and acute respiratory infections hit the community hard. The researchers – led by Venkatashiva Reddy of the All India Institute of Medical Sciences, New Delhi – suggested that social exclusion of the low-status tribe was a driver of ill health.

What Corsi and Subramanian have pointed out in their study may be the tip of an iceberg. Other research is showing that India’s disease prevalence is much more complex and diverse than previously thought.

The country contains more than 2000 ethnic groups with genetically distinct ancestry and diverse lifestyles.

According to a 2017 paper in the journal The Lancet, it has undergone heterogeneous economic growth over the past few decades, leading to wide variations in health and disease distribution.

Multiple researchers, members of the India State-Level Burden Initiative, analysed 333 disease conditions and injuries and 84 risk factors for every state of India from 1990 to 2016. They found that the burden from major communicable diseases such as diarrhoea, lower respiratory tract infections and tuberculosis, as well as neonatal disorders, remained high relative to other countries, despite increasing wealth.   

Unabated urbanisation and ageing of the population add to the woes, posing major challenges to the Indian health system over the next few decades. By 2050, half of India’s populations are projected to be urbanites, up from a third at present.

The risks inherent in this scenario are clear to Corsi and Subramanian.

“India has experienced tremendous economic growth in recent decades, but improvements have been remarkably uneven and concentrated among a small minority,” they conclude.

“There is a risk that health care resources could follow a similar trajectory amid the target of universal health coverage.”