Over half of those aged 20 now may get diabetes, finds study

NEW DELHI: A little over one in two men (56%) and close to twothirds (65%) of women who are now 20 years old are likely to develop diabetes later in life, according to an international study on the lifetime risk of diabetes in people living in urban India. Lifetime risk is the cumulative probability of developing diabetes over the course of life.

Obesity raised the chances of developing diabetes substantially, with the lifetime risk being highest among obese metropolitan Indians -- as high as 86% among 20-year-old women and 87% among men of the same age.

“The numbers are alarming across the spectrum of weight and rises dramatically with higher weight. The risk is 85% for people who are obese, which is massive,” said the study’s co-author, Professor Nikhil Tandon of the Department of Endocrinology and Metabolism at the All India Institute of Medical Sciences (AIIMS), New Delhi.

“People with healthy or lower weight had considerably higher diabetes-free life expectancy, which means diabetes prevention, testing and treatment must be made a national priority, particularly given the rapid increase in urban obesogenic environments,” Tandon added.

Being thin lowered risk. People who have normal or underweight Body Mass Index (BMI) lived out 80-85% of their remaining years diabetes-free, compared to obese 20-year-olds who have only 46-52% of their remaining life years disease-free, according to the paper published in Diabetologia, which is the journal of the European Association for the Study of Diabetes.

Those who were free of diabetes at the age of 60 years had lower risk, with around 38% of women and 28% of men developing diabetes at a later age, found the study that used data from Delhi and Chennai. Women consistently had a higher lifetime risk across the lifespan.

Adult-onset diabetes would account for 95% of the cases, found researchers from India, the US and the UK, who were led by Dr Shammi Luhar from the Department of Public Health and Primary Care, University of Cambridge, UK.

The study used age-, sex- and BMI-specific incidence rates of diabetes in urban India taken from the Centre for Cardiometabolic Risk Reduction in South Asia (2010–2018); age-, sex- and urban-specific rates of mortality from period lifetables reported by the Government of India (2014); and prevalence of diabetes from the Indian Council of Medical Research’s India Diabetes study (2008–2015).

A US study using data from 2000–2011 reported a lifetime diabetes risk of 40% among men and women aged 20 years from the general population.

“Our new estimates from India are much closer to estimates of lifetime risk of diabetes of 20-year-olds among the black and Hispanic populations in the US (above 50%), groups considered at a higher risk of developing diabetes than the general population,” said the study.

“Indians seem to have a more rapid decline in beta cell function at much lower BMI and progress towards diabetes at least a decade earlier than Caucasians. So while genes do have a pre-disposive role, the gene-environment interaction is also important as an unhealthy lifestyle can tilt the balance,” said Dr Tandon.

“High risk of diabetes in urban populations has been shown in other studies, and this detailed analysis further consolidates it... However, we need further studies to corroborate these since this research is based on a modelling analysis,” said Dr Anoop Misra, chairman, FortisC-DOC Centre for Diabetes, Metabolic Diseases and Endocrinology, New Delhi.

In India, 77 million adults have diabetes and this number is expected to almost double to 134 million by 2045. Urbanisation, unhealthy diets and increasing inactivity, coupled with the relatively high predisposition of Indians and other South Asian populations to developing diabetes at both lower ages (up to a decade earlier) and lower BMIs, when compared with white European populations, are fuelling a hidden epidemic.

“Such high probabilities of developing diabetes will have severely negative implications for India’s already strained health system and also out-ofpocket expenditure on diabetes treatment by patients, unless diabetes is immediately acknowledged for what it is: one of the most important threats to public health in India.,” said Dr Luhar.