Risk assessment and prediction for lung cancer among Hong Kong Chinese men.

OBJECTIVE: Most of the previous risk prediction models for lung cancer were developed from smokers, with discriminatory power ranging from 0.57 to 0.72. We constructed an individual risk prediction model for lung cancer among the male general population of Hong Kong. METHODS: Epidemiological data of 1,069 histology confirmed male lung cancer cases and 1,208 community controls were included in this analysis. Residential radon exposure was retrospectively reconstructed based on individual lifetime residential information. Multivariable logistic regression with repeated cross-validation method was used to select optimal risk predictors for each prediction model for different smoking strata. Individual absolute risk for lung cancer was estimated by Gail model. Receiver-operator characteristic curves, area under the curve (AUC) and confusion matrix were evaluated to demonstrate the model performance and ability to differentiate cases from non-cases. RESULTS: Smoking and smoking cessation, education, lung disease history, family history of cancer, residential radon exposure, dietary habits, carcinogens exposure, mask use and dust control in workplace were selected as the risk predictors for lung cancer. The AUC of estimated absolute risk for all lung cancers was 0.735 (95% CI: 0.714-0.756). Using 2.83% as the cutoff point of absolute risk, the predictive accuracy, positive predictive value and negative predictive value were 0.715, 0.818 and 0.674, respectively. CONCLUSION: We developed a risk prediction model with moderate discrimination for lung cancer among Hong Kong males. External validation in other populations is warranted for this model in future studies.

Lung cancer risk in painters: results from the SYNERGY pooled case-control study consortium.

OBJECTIVES: We evaluated the risk of lung cancer associated with ever working as a painter, duration of employment and type of painter by histological subtype as well as joint effects with smoking, within the SYNERGY project. METHODS: Data were pooled from 16 participating case-control studies conducted internationally. Detailed individual occupational and smoking histories were available for 19 369 lung cancer cases (684 ever employed as painters) and 23 674 age-matched and sex-matched controls (532 painters). Multivariable unconditional logistic regression models were adjusted for age, sex, centre, cigarette pack-years, time-since-smoking cessation and lifetime work in other jobs that entailed exposure to lung carcinogens. RESULTS: Ever having worked as a painter was associated with an increased risk of lung cancer in men (OR 1.30; 95% CI 1.13 to 1.50). The association was strongest for construction and repair painters and the risk was elevated for all histological subtypes, although more evident for small cell and squamous cell lung cancer than for adenocarcinoma and large cell carcinoma. There was evidence of interaction on the additive scale between smoking and employment as a painter (relative excess risk due to interaction >0). CONCLUSIONS: Our results by type/industry of painter may aid future identification of causative agents or exposure scenarios to develop evidence-based practices for reducing harmful exposures in painters.

Smoking cessation sharply reduced lung cancer mortality in a historical cohort of 3185 Chinese silicotic workers from 1981 to 2014.

BACKGROUND: Population-based studies showed an over 50% decrease in lung cancer risk after quitting smoking for 5-6 years, but the beneficial effect in silicotics remains unknown. We aimed to rectify this knowledge gap using a large historical cohort of 3185 Chinese silicotics since 1981 and followed-up till 2014. METHODS: Baseline information on workers' socio-demographics, smoking habits, occupational history, and medical history was collected. Smoking status was reassessed during follow-up. Multiple Cox proportional hazards model was performed to evaluate the impact of smoking cessation on lung cancer mortality. RESULTS: Overall, 1942 deaths occurred and 188 lung cancer deaths were identified. Compared with never quitters, silicotics who were new quitters had almost halved their lung cancer risk [hazard ratio (HR) = 0.51, 95%CI: 0.34-0.76], while persistent quitters had a 53% risk reduction (HR = 0.47, 95%CI: 0.33-0.66). Lung cancer mortality approximately halved after quitting smoking for 10 years. While the risk kept decreasing with years since cessation, it did not reverse back to that of never smokers. Persistent quitters with small opacities tended to have higher beneficial effects than those with large opacities. CONCLUSIONS: Smoking cessation for 10 years halved lung cancer mortality among silicotics, while the beneficial effect was prominent for patients with small opacities.

Nighttime eating and breast cancer among Chinese women in Hong Kong.

BACKGROUND: A novel line of research suggests that eating at nighttime may have several metabolic consequences that are highly relevant to breast cancer. We investigated the association between nighttime eating habits after 10 p.m. and breast cancer in Hong Kong women. METHODS: A hospital-based case-control study was conducted during 2012-2015. A total of 922 patients with incident breast cancer (cases) and 913 hospital controls were recruited and interviewed using a standard questionnaire including information on eating behavior during both daytime and nighttime. We collected the timing, duration, types and frequencies of food intake of eating at nighttime. Odds ratios (ORs) for the risk of breast cancer in relation to nighttime eating-related variables were calculated by unconditional multivariable logistic regression. RESULTS: Eating at night after 10 pm was significantly associated with breast cancer with an adjusted OR of 1.50 (95% confidence interval (CI) 1.06-2.12, P = 0.02), and the associations were stronger in women who had the longest duration of nighttime eating (≥20 years) (adjusted OR = 2.28 (95% CI 1.13-4.61, P = 0.02) and who ate late (midnight to 2 a.m.) (adjusted OR = 2.73, 95% CI 1.01-6.99, P = 0.04). Interestingly, nighttime eating was only associated with breast cancer among women who consumed staple foods (OR = 2.16, 95% CI 1.42-3.29, P < 0.001) but not those who ate vegetables or fruits as nighttime meals. The significant association between nighttime eating and breast cancer was observed among women with body mass index (BMI) <25 (OR = 2.29, 95% CI 1.48-3.52, P < 0.001) but not among women with BMI ≥25. CONCLUSIONS: Results from this study suggest a possible association between nighttime eating behavior and breast cancer. These findings need to be confirmed by independent large studies.

Disparities of time trends and birth cohort effects on invasive breast cancer incidence in Shanghai and Hong Kong pre- and post-menopausal women.

BACKGROUND: Breast cancer is the leading cause of cancer morbidity among Shanghai and Hong Kong women, which contributes to 20-25% of new female cancer incidents. This study aimed to describe the temporal trend of breast cancer and interpret the potential effects on the observed secular trends. METHODS: Cancer incident data were obtained from the cancer registries. Age-standardized incidence rate was computed by the direct method using the World population of 2000. Average annual percentage change (AAPC) in incidence rate was estimated by the Joinpoint regression. Age, period and cohort effects were assessed by using a log-linear model with Poisson regression. RESULTS: During 1976-2009, an increasing trend of breast cancer incidence was observed, with an AAPC of 1.73 [95% confidence interval (CI): 1.54-1.92)] for women in Hong Kong and 2.83 (95% CI, 2.26-3.40) in Shanghai. Greater upward trends were revealed in Shanghai women aged 50 years old or above (AAPC = 3.09; 95% CI, 1.48-4.73). Using age at 50 years old as cut-point, strong birth cohort effects were shown in both pre- and post-menopausal women, though a more remarkable effect was suggested in Shanghai post-menopausal women. No evidence for a period effect was indicated. CONCLUSIONS: Incidence rate of breast cancer has been more speedy in Shanghai post-menopausal women than that of the Hong Kong women over the past 30 years. Decreased birth rate and increasing environmental exposures (e.g., light-at-night) over successive generations may have constituted major impacts on the birth cohort effects, especially for the post-menopausal breast cancer; further analytic studies are warranted.

Occupational risk factors for nasopharyngeal carcinoma in Hong Kong Chinese: a case-referent study.

PURPOSE: This study aimed to investigate the occupational risk factors for nasopharyngeal carcinoma (NPC) in Hong Kong Chinese. METHODS: We conducted a case-referent study with 352 incident cases and 410 referents recruited between June 2010 and December 2012. Full occupational histories were obtained via face-to-face interviews. Unconditional logistic regressions were performed to estimate the odds ratios (ORs) for NPC associated with occupational risk factors. RESULTS: Workers of craft related trades and elementary occupations were at elevated NPC risk with the adjusted ORs of 2.09 [95% confidence interval (CI) 1.09, 4.01] and 2.14 (95% CI 1.04, 4.41), respectively, compared with those clerical support workers as the reference group. Occupational exposures to cotton dust, chemical fumes, and welding fumes were significantly associated with increased NPC risk after adjustment for confounders [adjusted ORs (95% CIs) 1.93 (1.13, 3.28), 13.11 (1.53, 112.17), and 9.18 (1.05, 80.35), respectively]. We also observed significant exposure-response relationship for the duration of exposure to cotton dust (P for trend = 0.0175). Those with occupational exposure to cotton dust for 15 years or more were at significantly increased risk of NPC (adjusted OR 2.08, 95% CI 1.01, 4.28). CONCLUSIONS: This study indicates that employment in craft related trades and elementary occupations, as well as occupational exposures to chemical fumes, welding fumes, and cotton dust may be associated with an increased risk of NPC. Further epidemiological studies remain warranted to clarify the roles of specific occupational risk factors on NPC development.

Secondhand Smoke Enhances Lung Cancer Risk in Male Smokers: An Interaction.

INTRODUCTION: Previous studies revealed that some indoor air pollutants and fine particle matter can interact with active smoking, enhancing lung cancer risk in smokers. Secondhand smoke (SHS), with remarkable differences from active smoking, contributes significantly to indoor air pollution and generates a considerable amount of fine particle matter, may cause a similar interaction with active smoking. METHODS: Information on lifetime SHS along with active smoking and other confirmed or suspected risk factors for lung cancer was collected in this case-referent study. Odds ratios and the 95% confidence intervals (95% CIs) of smoking status in different levels of SHS were evaluated. Potential multiplicative and additive interactions were explored. RESULTS: Compared with never-smokers without SHS, current smokers who were exposed to a high level of SHS demonstrated the highest odds ratio (15.13, 95% CI: 8.60, 26.65), almost doubles the effect in the current smokers without SHS. Significant additive interactions between current smoking and high level of SHS were observed for all lung cancers (synergy index = 1.80, 95% CI: 1.02, 3.24) and the squamous carcinoma subgroup. CONCLUSIONS: High level of SHS exposure greatly enhanced lung cancer risk among current smokers, consistent with an additive interaction; while this interaction was predominant for the squamous carcinoma. The results provide new evidence to the rationale of promoting global smoking cessation. IMPLICATIONS: Some indoor air pollutants can interact with active smoking, yielding a synergistic effect on inducing lung cancer. SHS, with noticeable differences from active smoking, is a major source of indoor air pollution. However, little has been known about the effect of SHS in smokers and whether there is a similar interaction between SHS and active smoking. In this study, we evaluated their separate and joint effects and indeed found a more than additive interaction between them. This finding suggests a potential problem of gathering smoking aggravating by venue restriction policies and re-advocates policy efforts on smoking cessation.

Exposure-response estimate for lung cancer and asbestosis in a predominantly chrysotile-exposed Chinese factory cohort.

BACKGROUND: Cumulative fiber exposures, predominantly chrysotile, were estimated in a Chinese asbestos worker cohort and exposure-response relationships with lung cancer mortality and cumulative incidence of asbestosis were determined. METHODS: Individual time-dependent cumulative exposures were estimated for 577 asbestos workers, followed prospectively for 37 years. Occupational history and smoking data were obtained from company records and personal interviews; vital status and causes of death were ascertained from death registries and hospital records. Hazard ratios were generated for disease outcomes, with adjustments for smoking and age. RESULTS: Median cumulative fiber exposure for the cohort was 132.6 fiber-years/ml (IQR 89.3-548.4). Exposure-response relationships were demonstrated for both disease outcomes, with nearly sixfold and threefold increased risks seen at the highest exposure level for lung cancer deaths and asbestosis, respectively. CONCLUSION: Evidence using quantitative exposure estimates was provided for increased risks of lung cancer mortality and development of asbestosis in a predominantly chrysotile-exposed cohort.

Lung cancer risk among bricklayers in a pooled analysis of case-control studies.

Bricklayers may be exposed to several lung carcinogens, including crystalline silica and asbestos. Previous studies that analyzed lung cancer risk among these workers had several study design limitations. We examined lung cancer risk among bricklayers within SYNERGY, a large international pooled analysis of case-control studies on lung cancer and the joint effects of occupational carcinogens. For men ever employed as bricklayers we estimated odds ratios (OR) and 95% confidence intervals (CI) adjusted for study center, age, lifetime smoking history and employment in occupations with exposures to known or suspected lung carcinogens. Among 15,608 cases and 18,531 controls, there were 695 cases and 469 controls who had ever worked as bricklayers (OR: 1.47; 95% CI: 1.28-1.68). In studies using population controls the OR was 1.55 (95% CI: 1.32-1.81, 540/349 cases/controls), while it was 1.24 (95% CI: 0.93-1.64, 155/120 cases/controls) in hospital-based studies. There was a clear positive trend with length of employment (p < 0.001). The relative risk was higher for squamous (OR: 1.68, 95% CI: 1.42-1.98, 309 cases) and small cell carcinomas (OR: 1.78, 95% CI: 1.44-2.20, 140 cases), than for adenocarcinoma (OR: 1.17, 95% CI: 0.95-1.43, 150 cases) (p-homogeneity: 0.0007). ORs were still elevated after additional adjustment for education and in analyses using blue collar workers as referents. This study provided robust evidence of increased lung cancer risk in bricklayers. Although non-causal explanations cannot be completely ruled out, the association is plausible in view of the potential for exposure to several carcinogens, notably crystalline silica and to a lesser extent asbestos.

Tobacco smoking, family history, and the risk of nasopharyngeal carcinoma: a case-referent study in Hong Kong Chinese.

PURPOSE: This study aimed to investigate the associations of tobacco smoking and family history of nasopharyngeal carcinoma (NPC) with the risk of NPC in Hong Kong Chinese. METHODS: Between June 2010 and December 2012, we conducted a case-referent study with 352 incident cases and 410 referents in Hong Kong. We collected information on tobacco smoking and family history of NPC via face-to-face interviews. RESULTS: There were 174 (49.4%) and 131 (32.0%) ever-smokers among cases and referents, respectively. The adjusted odds ratio (OR) for NPC related to current smoking was 1.67 [95% confidence interval (CI) 1.06, 2.61]. Exposure-response relationships were observed between years and total pack-years of smoking, and NPC risk (p = 0.001 and p = 0.018, respectively). History of NPC in first-degree relatives was associated with an increased NPC risk (adjusted OR = 4.52, 95% CI 2.39, 8.55). The increased NPC risk associated with sibling history (adjusted OR = 6.80, 95% CI 2.63, 17.56) was higher than that for parental history (adjusted OR = 3.04, 95% CI 1.27, 7.25). The adjusted OR for ever-smokers with family history using never-smokers without family history as the reference was 4.54 (95% CI 1.67, 12.34). CONCLUSIONS: This study verified the important roles of tobacco smoking and family history on NPC risk among Hong Kong Chinese. The provided evidence supported the knowledge that both environmental exposures and inherited susceptibility contributed to the risk of NPC.

Severe acute respiratory syndrome beyond Amoy Gardens: completing the incomplete legacy.

The temporal and spatial distributions of the 2003 severe acute respiratory syndrome (SARS) outbreak in Amoy Gardens of Hong Kong was reexamined using all confirmed cases. The outbreak actually extended to nearby residential complexes. Airborne spread was the most likely explanation, and the SARS coronavirus could have spread over a distance of 200 m.

Short-term associations of cause-specific emergency hospitalizations and particulate matter chemical components in Hong Kong.

Despite an increasing number of recent studies, the overall epidemiologic evidence associating specific particulate matter chemical components with health outcomes has been mixed. The links between components and hospitalizations have rarely been examined in Asia. We estimated associations between exposures to 18 chemical components of particulate matter with aerodynamic diameter less than 10 µm (PM10) and daily emergency cardiorespiratory hospitalizations in Hong Kong, China, between 2001 and 2007. Carbonaceous particulate matter, sulfate, nitrate, and ammonium accounted for two-thirds of the PM10 mass. After adjustment for time-varying confounders, a 3.4-µg/m(3) increment in 2-day moving average of same-day and previous-day nitrate concentrations was associated with the largest increase of 1.32% (95% confidence interval: 0.73, 1.92) in cardiovascular hospitalizations; elevation in manganese level (0.02 µg/m(3)) was linked to a 0.91% (95% confidence interval: 0.19, 1.64) increase in respiratory hospitalizations. Upon further adjustment for gaseous copollutants, nitrate, sodium ion, chloride ion, magnesium, and nickel remained significantly associated with cardiovascular hospitalizations, whereas sodium ion, aluminum, and magnesium, components abundantly found in coarser PM10, were associated with respiratory hospitalizations. Most positive links were seen during the cold season. These findings lend support to the growing body of literature concerning the health associations of particulate matter composition and provide important insight into the differential health risks of components found in fine and coarse modes of PM10.

Socio-economic influence on weight status through time in schoolchildren.

AIM: This paper describes the developmental trajectory of adiposity in relation to socio-demographic status in primary schoolchildren studying in local schools in Hong Kong. METHODS: Body mass index (BMI) and prevalence of overweight and obesity were determined in a cohort of primary schoolchildren annually from 2001/2002 to 2005/2006. To study the associations between socio-demographic status and adiposity, repeated measures analysis of variance was used for the longitudinal change in BMI, while logistic regression was used with overweight and obesity development as outcomes. RESULTS: Prevalence of overweight and obesity was 12.1% and 4.0%, respectively, at baseline, and 16.7% and 3.3%, respectively, at the end of the study period. Boys were more likely to be overweight and obese. Parents in the 'Professional' occupational group were less likely to have overweight and obese children. Among 32,781 children with normal weight at baseline, 2885 (8.8%) became overweight or obese after 4 years. Among 6286 children who were initially overweight or obese, 2079 (33.1%) returned to normal weight. Boys were more likely to move up from normal weight to overweight or obesity and less likely to move down the opposite direction during the study period. Parental education at degree level and the occupational group of 'Professionals' were, in general, associated with more favourable changes in weight status during follow-up. CONCLUSION: Overweight and obesity were not firmly established during early primary school years. Interventions at the school level on students and their parents might help prevent and control the future development of the obesity epidemic in the population.

Corrigendum: Evaluation of N95 respirators on fit rate, real-time leakage, and usability among Chinese healthcare workers: study protocol of a randomized crossover trial.

[This corrects the article DOI: 10.3389/fpubh.2023.1266607.].

Welding and lung cancer in a pooled analysis of case-control studies.

Several epidemiologic studies have indicated an increased risk of lung cancer among welders. We used the SYNERGY project database to assess welding as a risk factor for developing lung cancer. The database includes data on 15,483 male lung cancer cases and 18,388 male controls from 16 studies in Europe, Canada, China, and New Zealand conducted between 1985 and 2010. Odds ratios and 95% confidence intervals between regular or occasional welding and lung cancer were estimated, with adjustment for smoking, age, study center, and employment in other occupations associated with lung cancer risk. Overall, 568 cases and 427 controls had ever worked as welders and had an odds ratio of developing lung cancer of 1.44 (95% confidence interval: 1.25, 1.67) with the odds ratio increasing for longer duration of welding. In never and light smokers, the odds ratio was 1.96 (95% confidence interval: 1.37, 2.79). The odds ratios were somewhat higher for squamous and small cell lung cancers than for adenocarcinoma. Another 1,994 cases and 1,930 controls had ever worked in occupations with occasional welding. Work in any of these occupations was associated with some elevation of risk, though not as much as observed in regular welders. Our findings lend further support to the hypothesis that welding is associated with an increased risk of lung cancer.

Lung cancer risk among hairdressers: a pooled analysis of case-control studies conducted between 1985 and 2010.

Increased lung cancer risks among hairdressers were observed in large registry-based cohort studies from Scandinavia, but these studies could not adjust for smoking. Our objective was to evaluate the lung cancer risk among hairdressers while adjusting for smoking and other confounders in a pooled database of 16 case-control studies conducted in Europe, Canada, China, and New Zealand between 1985 and 2010 (the Pooled Analysis of Case-Control Studies on the Joint Effects of Occupational Carcinogens in the Development of Lung Cancer). Lifetime occupational and smoking information was collected through interviews with 19,369 cases of lung cancer and 23,674 matched population or hospital controls. Overall, 170 cases and 167 controls had ever worked as hairdresser or barber. The odds ratios for lung cancer in women were 1.65 (95% confidence interval (CI): 1.16, 2.35) without adjustment for smoking and 1.12 (95% CI: 0.75, 1.68) with adjustment for smoking; however, women employed before 1954 also experienced an increased lung cancer risk after adjustment for smoking (odds ratio = 2.66, 95% CI: 1.09, 6.47). The odds ratios in male hairdressers/barbers were generally not elevated, except for an increased odds ratio for adenocarcinoma in long-term barbers (odds ratio = 2.20, 95% CI: 1.02, 4.77). Our results suggest that the increased lung cancer risks among hairdressers are due to their smoking behavior; single elevated risk estimates should be interpreted with caution and need replication in other studies.

Silicosis.

Silicosis is a fibrotic lung disease caused by inhalation of free crystalline silicon dioxide or silica. Occupational exposure to respirable crystalline silica dust particles occurs in many industries. Phagocytosis of crystalline silica in the lung causes lysosomal damage, activating the NALP3 inflammasome and triggering the inflammatory cascade with subsequent fibrosis. Impairment of lung function increases with disease progression, even after the patient is no longer exposed. Diagnosis of silicosis needs carefully documented records of occupational exposure and radiological features, with exclusion of other competing diagnoses. Mycobacterial diseases, airway obstruction, and lung cancer are associated with silica dust exposure. As yet, no curative treatment exists, but comprehensive management strategies help to improve quality of life and slow deterioration. Further efforts are needed for recognition and control of silica hazards, especially in developing countries.

Lung cancer risk among bakers, pastry cooks and confectionary makers: the SYNERGY study.

INTRODUCTION: Some studies have suggested increased lung cancer risks among bakers, however the results overall were inconsistent. The authors studied lung cancer risks among bakers and baking-related occupations in the SYNERGY pooled case-control database from 16 countries. METHODS: Occupation in a baking-related job was identified from the subjects' job histories. ORs adjusted for log(age), study centre, smoking behaviour and ever employment in a job with known exposure to occupational lung carcinogens were calculated by unconditional logistic regression. Findings were stratified by sex, histological subtype of lung cancer and smoking status. RESULTS: 19 366 cases (15 606 men) and 23 670 control subjects (18 528 men) were included. 473 cases (415 men, 58 women) and 501 controls (437 men, 64 women) had ever worked in baking or a related job. We did not observe an increased risk for men in baking (OR 1.01; 95% CI 0.86 to 1.18). No linear trends were observed for duration of employment. Some results suggested increased lung cancer risks for women, for example, for working as a baker for >30 years and in never-smokers, but after exclusion of one study these increased risks disappeared. DISCUSSION: The findings from this study do not suggest increased lung cancer risks in baking-related professions.

Evaluation of N95 respirators on fit rate, real-time leakage, and usability among Chinese healthcare workers: study protocol of a randomized crossover trial.

Background: N95 respirators are used to limit the transmission of respiratory viruses in clinical settings. There are two to three major types of N95 available for all healthcare workers in Hong Kong. However, after the coronavirus outbreak and the consequent shortage of many commonly used respirators, several new N95 respirators were adopted temporarily in clinical settings without evaluation. Prior literature indicates that traditional N95 respirators used in hospitals in Hong Kong are not fit for Chinese people and have fit rates ranging from 50 to 60%. This study aims to investigate and compare the fit rate, real-time leakage, and mask usability of traditional and new N95 respirators among Chinese healthcare workers. Methods: This study will employ two sequential phases. Phase 1 has a cross-sectional exploratory design used to investigate the fit rate and mask usability of three types of respirators. Phase 2 will examine the effectiveness of respiratory protection by comparing traditional and new N95 respirators by a randomized crossover trial. Eligible participants will be randomly allocated through a controlled crossover experiment to either a traditional or new respirator group (n = 100 in each arm) for performing standard clinical procedures. The primary outcome (real-time leakage) will be recorded at 30 s intervals during nasopharyngeal suctioning and cardiopulmonary resuscitation. The secondary outcomes are the fit rate and mask usability. After a 2 min suctioning (15 s twice) and 4 min one-person CPR, the fit rate (assessed by standard N95 fit testing) and mask usability (measured by self-reported mask usability scale) will be recorded as data of post-procedure. After 10 min rest, measurement of real-time leakage (i.e., crossover), fit test, and usability will be repeated. Discussion: The result of real-time leakage will be a vital indicator of the respiratory protection of Chinese healthcare workers while performing prevalent clinical procedures, such as resuscitation. The fit rate and usability result will serve as an essential reference for consumable purchase policy in clinical settings.Trial registration: ISRCTN registry: ISRCTN40115047. Retrospectively registered on May 9, 2023. https://www.isrctn.com/ISRCTN40115047.

Processed food consumption and risk of esophageal squamous cell carcinoma: A case-control study in a high risk area.

This study was conducted to investigate the association between consumption of processed foods and esophageal cancer risk. A population-based case-control study was designed. For the present study, 254 patients with esophageal squamous cell carcinoma with pathological diagnoses were selected from Yanting during 2008 and 2010 and 254 community-based controls were selected from the same area, individually matched with cases by age and sex. Data on demographic, lifestyle and dietary factors were collected using food frequency questionnaires. A conditional logistic regression model was used to estimate the odds ratio (OR) with adjustments for potential confounders. Compared to the frequency of <1 time/week, the intake frequency of >3 times/week of preserved vegetables had a significant association with esophageal cancer (OR = 5.01, 95% confidence interval [CI] 2.07, 12.17). In stratified analyses, the OR of increasing intake of preserved vegetables for esophageal cancer were 2.02 in men (95% CI 1.18, 3.48), 3.15 in women (95% CI 1.28, 7.75), 2.41 (95% CI 1.45 4.01) in the persons <65 years old and 1.28 (95% CI 0.35, 4.65) in persons ≥65 years old. Consumption of pickled vegetables was not associated significantly with esophageal cancer risk. Intake of salted meat with a frequency of ≥1 time/week meant that the OR increased to 2.57 (95%CI 1.02, 6.43), but no significant trend or association in subgroup analysis was observed. Preserved vegetable consumption was associated with increased risk of esophageal cancer, while no association was found with pickled vegetables.