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| Photo Credit: Shiv Kumar Pushpakar

That the use of smokeless tobacco increases the risk of oral cancer is well known. In a new study, researchers from the M S Ramaiah University of Applied Sciences, Bengaluru have found that the risk of oral cancer due to chewing tobacco is particularly high in people older than 60 years. Also, oral cancer was not uniquely associated with men using chewing tobacco across all age groups, including in those older than 60 years. This would mean that both women and men are at equal risk of developing oral cancer caused by smokeless tobacco.

The study, which was published recently in the Journal of Indian Association of Public Health Dentistry, found that while smokeless tobacco increased the odds of developing oral cancer by nearly 13 times compared to smoked tobacco across all age groups, in people older than 60 years, smokeless tobacco increased the odds of developing oral cancer by 19.5 times compared to smoked tobacco. 

“Age plays a crucial role in the risk of developing oral cancer. This is largely because the longer a person lives, the more time there is for genetic damage and cellular changes to accumulate, which can lead to cancer. Although tobacco use is a well-known major risk factor, age-related changes in the body — regardless of tobacco use — also contribute to the increased risk of oral cancer in older populations,” says Dr. Danny John from the Department of Public Health at M S Ramaiah University of Applied Sciences, and a coauthor of the paper.

“The odds of developing oral cancer were alarmingly higher among elderly users of smokeless tobacco. Individuals consuming smokeless tobacco had nearly 19.5 times higher risk of developing oral cancer compared to non-users,” Dr. Amra Sultana from the Department of Public Health Dentistry at the M S Ramaiah University of Applied Sciences, and the corresponding author of the paper, says in an email.

“The use of betel quid with raw tobacco increases the risk of oral cancer by over 21 times,” says Dr. Sultana. “A clear dose-response relationship was also observed. Those using smokeless tobacco more than five times a day faced an approximately 39-fold increase in risk.”

Extended use of smokeless tobacco for over 20 years or more was linked to a nine-fold increase in cancer risk. The study did not show a statistically significant association between smoked tobacco — cigarettes and beedis — with oral cancer in people older than 60 years.

The study was an observational case-control study involving 120 adults and was carried out in a tertiary care dental institution situated in Kaiwara in the Chikkaballapur district, which is 70 km away from Bengaluru. Of the 120 people included in the study, 30 had oral cancer while the remaining 90 served as controls. The controls were selected from the places where cases were residing.