Cancer accounted for 8.3% of all deaths in 2016, double that of 1990. Cancer cases, too, doubled over the period — from 5.5 lakh in 1990, to 10.6 lakh in 2016. If you look at the absolute numbers, this is rather alarming. But when you factor in the way the population has aged in the 26 years — remember, cancer becomes more common as people age — there was hardly any change in the ‘age-standardised’ incidence rate. Here is a detailed look at how the ailment impacts Indians.
WHAT IS AGE-STANDARDISATION?
The occurrence of a disease may be more prevalent at certain ages, say, when you are older, than at others. As a result, if the proportion of people in that age group goes up over time, the overall prevalence will also go up even without any age group being worse off than before. Age-standardised data, therefore, adjusts data from two different time periods for the change in age structure so that they become comparable. According to the 1991 Census, 29% of the population were in the 35-79 age group (when most cases of cancer occur). By 2011, the population in this group had increased to 34%.
TOP CAUSES OF CANCER BY TYPE AND BY GENDER
* DALYs: Disablity Adjusted Life Years. It’s a measure of overall disease burden, expressed as number of years lost due to illness, disability or early death
FASTEST GROWING CANCER
The study looked at 28 types of cancer and found that
liver cancer was the fastest growing. The number of cases grew 206% over 26 years. But after age-standardisation, it grew by 51%. Cases of
stomach cancer actually dropped by a third after age-standardisation. Incidence of 12 types of cancer dropped over the period, if you look at the age-standardised data.
