Esophageal cancer in relation to alcohol drinking and tobacco use among men in Kerala, India - Karunagappally cohort.

BACKGROUND: In the Karunagappally cohort, esophageal cancer is the third most common cancer with an age-adjusted incidence rate of 6.2 per 100,000 person-years among men. The present study analyzed the risk of esophageal cancer in relation to alcohol drinking and tobacco use. METHODS: The study included 65,528 men aged 30-84 years in the Karunagappally cohort, India. RESULTS: Poisson regression analysis showed that alcohol drinking significantly increased (P = 0.027) the risk of esophageal cancer and the relative risk (RR) for current drinkers was 1.6, (95 % confidence interval (CI) = 1.1-2.3). The risk increased significantly in heavy alcohol drinkers (250 g of ethanol or above per day) (RR = 2.1, 95 % CI = 1.2-3.5) (P for trend = 0.014) and among current arrack consumers (RR = 1.8, 95 % CI = 0.99-3.29) (P for trend = 0.025). Current bidi and cigarette smokers showed an increase in the trend of cancer risk. A significantly higher risk was seen in those who had started smoking bidi before the age of 18 years, RR = 1.9 (95 % CI = 1.1-3.3) (P for trend = 0.044). Furthermore, increased RR for heavy bidi and cigarette smokers were 1.6 (95 % CI = 1.1-2.5) and 2.4 (95 % CI = 1.3-4.5), respectively. CONCLUSION: To the best of our knowledge, this is the first cohort study in India to report an increased esophageal cancer risk with respect to alcohol drinking.

Thyroid nodule prevalence among women in areas of high natural background radiation, Karunagappally, Kerala, India.

PURPOSE: Radiation exposure has been reported to cause thyroid nodules. The study area was Karunagapally, which has several areas with high natural radiation levels derived from thorium and its decay products. Since thyroid abnormalities are more common in women, the focus was only on women. METHODS: The examinations included interview, ultrasonography of the thyroid and serum assays of free thyroxine (FT4), thyrotropin (TSH), and anti-thyroglobulin levels. Cumulative dose during the childhood and lifetime cumulative dose (lagged by 5 years) were estimated. RESULTS: We examined 524 female residents aged 17-73 years and found 75 cases of solitary solid thyroid nodules. The prevalence of thyroid nodules were 14.1 % (n = 42) in high dose panchayats and 14.5% (n = 33) in low-dose panchayats. In the logistic regression analysis adjusted for age, the prevalence of solitary thyroid nodule was not linearly related to childhood cumulative dose (P for trend = 0.159) and lifetime cumulative dose (P for trend = 0.333). The prevalence of thyroiditis and hypothyroidism was not related to natural radiation exposure. Serum levels of FT4 or TSH were not related to natural radiation exposure. CONCLUSIONS: The results obtained from the present study do not support the increase of solitary thyroid nodule, thyroiditis or hypothyroidism in relation to high-natural-background-radiation exposure.

Gastric cancer risk in relation to tobacco use and alcohol drinking in Kerala, India--Karunagappally cohort study.

AIM: To assess the risk of gastric cancer (GC) in relation to tobacco use and alcohol drinking in the Karunagappally cohort in Kerala, South India. METHODS: This study examined the association of tobacco use and alcohol drinking with GC incidence among 65553 men aged 30-84 in the Karunagappally cohort. During the period from 1990-2009, 116 GC cases in the cohort were identified as incident cancers. These cases were identified from the population-based cancer registry. Information regarding risk factors such as socioeconomic factors and tobacco and alcohol habits of cohort members were collected from the database of the baseline survey conducted during 1990-1997. The relative risks (RRs) and the corresponding 95% confidence intervals (95%CIs) for tobacco use were obtained from Poisson regression analysis of grouped survival data, considering age, follow-up period, occupation and education. RESULTS: Bidi smoking was associated with GC risk (P = 0.042). The RR comparing current versus never smokers was 1.6 (95%CI: 1.0-2.5). GC risk was associated with the number of bidis smoked daily (P = 0.012) and with the duration of bidi smoking (P = 0.036). Those who started bidi smoking at younger ages were at an elevated GC risk; the RRs for those starting bidi smoking under the age of 18 and ages 18-22 were 2.0 (95%CI: 1.0-3.9) and 1.8 (95%CI: 1.1-2.9), respectively, when their risks were compared with lifetime non-smokers of bidis. Bidi smoking increased the risk of GC among never cigarette smokers more evidently (RR = 2.2; 95%CI: 1.3-4.0). GC risk increased with the cumulative amount of bidi smoking, which was calculated as the number of bidis smoked per day x years of smoking (bidi-year; P = 0.017). Cigarette smoking, tobacco chewing or alcohol drinking was not significantly associated with GC risk. CONCLUSION: Among a male cohort in South India, gastric cancer risk increased with the number and duration of bidi smoking.

Estimation of external dose by car-borne survey in Kerala, India.

A car-borne survey was carried out in Kerala, India to estimate external dose. Measurements were made with a 3-in × 3-in NaI(Tl) scintillation spectrometer from September 23 to 27, 2013. The routes were selected from 12 Panchayats in Karunagappally Taluk which were classified into high level, mid-level and low level high background radiation (HBR) areas. A heterogeneous distribution of air kerma rates was seen in the dose rate distribution map. The maximum air kerma rate, 2.1 µGy/h, was observed on a beach sand surface. 232Th activity concentration for the beach sand was higher than that for soil and grass surfaces, and the range of activity concentration was estimated to be 0.7-2.3 kBq/kg. The contribution of 232Th to air kerma rate was over 70% at the measurement points with values larger than 0.34 µGy/h. The maximum value of the annual effective dose in Karunagappally Taluk was observed around coastal areas, and it was estimated to be 13 mSv/y. More than 30% of all the annual effective doses obtained in this survey exceeded 1 mSv/y.

Associations of tobacco use and alcohol drinking with laryngeal and hypopharyngeal cancer risks among men in Karunagappally, Kerala, India -Karunagappally cohort study.

BACKGROUND: From among a cohort of 65,553 men aged 30-84 in Karunagappally Taluk, Kerala, India, 52 hypopharyngeal cancer cases and 85 laryngeal cancer cases were identified by the Karunagappally Cancer Registry during the period between 1990 and 2009. METHODS: We conduct Poisson regression analysis of grouped data, taking into account age and education. RESULTS: This study showed that the incidence rates of cancers of the hypopharynx and the larynx were strongly related to the number of bidis smoked a day (P<0.001 for both hypopharyngeal and laryngeal cancers) and duration of bidi smoking (P=0.009; P<0.001). Laryngeal cancer risk was significantly increased by bidi smoking (P<0.001), cigarette smoking (P=0.013) and regular alcohol use (P=0.005). CONCLUSION: The present study, the first cohort study to examine the association of hypopharyngeal and laryngeal cancer incidence rates with bidi smoking in South Asia, clearly showed dose-response relationships between those cancer risks and bidi smoking; larger amounts of bidi smoked a day and longer durations of bidi smoking increased the incidence rates of those cancers. Tobacco chewing was found not related to the risk of hypopharynx or larynx cancer.