Hookah smoking and lung cancer in the Kashmir valley of the Indian subcontinent.

BACKGROUND: The literature about the causal relationship between lung cancer and tobacco smoking mostly concerns cigarettes. Hookah smoking is popular in the Kashmir valley of the Indian subcontinent, and is generally believed to be innocuous because of the passage of the smoke through water before inhalation. OBJECTIVE: To determine the relationship of hookah smoking to lung cancer in Kashmir. MATERIALS AND METHODS: In a case-control design, 251 cases of lung cancer and 500 age-matched controls were studied. A predefined questionnaire was administered through a personal interview regarding various smoking and dietary patterns and the results compared through statistical analyses. RESULTS: There were 194 (178 current) ever-smokers amongst the cases and 223 (134 current) amongst controls. Smokers had a 4.2 times risk of lung cancer compared to non smokers (OR 4.23, 95% CI 3.0-5.96, p < 0.0001). There were 120 hookah smokers amongst the cases and 100 amongst the controls and hookah smokers were nearly six times at risk for lung cancer as compared to nonsmokers (OR 5.83, (95% CI 3.95-8.60, p < 0.0001). Cigarette smokers were commoner amongst cases (46 vs 64 in controls; OR 3.49, 95% CI 2.18-5.60, p=0.000). The severity of smoking was associated with a higher risk of lung cancer (Chi-square 72.1, p 0.000).The practice of changing water of the hookah after each session proved non-existent. CONCLUSION: Hookah smoking is associated with a significantly higher risk for lung cancer in Kashmiri population, with about 6 fold elevated risk as compared to non-smoking controls.

Lung cancer in the Kashmir valley.

BACKGROUND: Lung cancer has been found to be the second commonest cancer according to a hospital-based data from Kashmir, India. However, no incidence studies are available. OBJECTIVE: To ascertain the incidence of lung cancer in Kashmir. MATERIALS AND METHODS: All newly histologically diagnosed cases of lung cancer seen in various hospital and private laboratories of the Kashmir valley were registered over a period of two years (January 1, 2004 to December 31, 2005). Also included were patients attending the various oncological service areas of the institute and those diagnosed from any other laboratory outside the state. The incidence rate was calculated using the January 2005 population as the reference population estimated using the census-based projected populations. RESULTS: Four hundred and sixty-two incident cases of lung cancer were seen during the study period. The crude incidence rate, age standardized (world) and truncated age adjusted (40-69 years, world) incidence rates for lung cancer per 100 000 population were 4.01, 6.48 and 15.28 respectively (males 6.55, 10.09 and 23.94 respectively and females 1.19, 2.14 and 4.65). The age adjusted rates for males in district Srinagar was 19.34 per 100 000. One hundred and fifty nine (69.8%) of the 221 had a history of Hukkah smoking. CONCLUSIONS: Even though Kashmir as a whole is a low incidence area for lung cancer (ASR of < 15), Srinagar district has the highest incidence of lung cancer among the males in Kashmir. The data presented is assumed to be the closest approximation to a population-based data registry and the geographical incidence maps of ICMR need appropriate updating.