KARACHI, July 12: A sharp increase in tobacco-related cancers in the country has been reported as a result of continuous negligence and failure on part of the health department to take action against the responsible people/organizations.

Smoking is the major cause of cancer as well as an important determinant of other neoplasm and non-neoplasmic diseases. In Pakistan, a nation-wide survey found that 21.6 per cent of the patients, aged 15 or above, were smokers with a higher proportion among men (36%) and women (9%).

A comprehensive data gathered from the Liaquat National Hospital, Jinnah Postgraduate Medical Centre and the Civil Hospital Karachi showed that lung cancer, an outcome of excessive tobacco use, was one of the “major threats” to the country.

Another study by Karachi Cancer Registry showed that lung cancer was the most frequent among men in the defunct district south, age-standardized incidence rate reaching 20.3/100,000, while for women the rate was 2.9/100,000. The results for entire Karachi (population 9,802,134) also showed a similar risk 17/100,000 for men and 2.1/100,000 for women.

The implications of this result are enormous in a very large country with little effort to control the spreading of smoking. The study has also provided evidence of a carcinogenic effect of tobacco products other than cigarettes. A possible role of occupational carcinogens and indoor air pollutants was also suggested.

The study was aimed at investigating environmental risk factors of lung cancer. The primary role of tobacco smoking as a case of lung cancer was confirmed. The risk appeared to be slightly higher among biri smokers than among cigarette smokers. Indeed as biris do not burn efficiently, it must be puffed continuously, resulting in delivery of higher dose of tar and nicotine.

Despite a small number of smokers among women, the study confirmed the central role of tobacco in lung carcinogenesis in the group. The limitation of the spread of smoking epidemic among women offers a major opportunity for control of the burden of cancer and other chronic diseases in the future, the study suggested.

Chewing of tobacco was only marginally associated with increased lung cancer risk. However, heavy exposure to this habit resulted in a significantly elevated odd ratio.

Analysis on sources of indoor air pollution was limited by the crudeness of information collected.

Smokers in the study were defined as those having smoked at least once a day for a minimum period of six months. In order to combine the consumption of different tobacco brands, the products were calculated cigarette-equivalents by using the weight: 0.75 for biri, 3 for pipe, 4 for cigar and 20 for hookah.

The subjects were asked about their places of residences, including fuels commonly used for cooking and heating. It generated variables of ever exposure to each type of fuel. All subjects reported living in homes equipped with a cooking system, while 73 per cent of subjects never sued a heating system.

The majority of subjects were 46 to 65 years of age. The proportion of men stood approximately 90 per cent in both cases and controls.

An increased risk for lung cancer was observed among habitual smokers and more especially among current smokers.—PPI