Golestan cohort study of oesophageal cancer: feasibility and first results

Hot beverage intake and oesophageal cancer in the UK Biobank: prospective cohort study

BACKGROUND

Drinking maté, a type of tea consumed at a very hot temperature in South America has been considered as a risk factor for oesophageal squamous cell carcinoma (ESCC).

METHODS

We assessed daily intake and preferred temperature of hot beverages (tea and coffee) in relation to incident ESCC (n = 242) and adenocarcinoma (EAC; n = 710) among 454,796 adults in the UK Biobank. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards regression.

RESULTS

Relative to non-drinkers and warm temperature drinkers (referent group), drinking 4-6 cups/d (HR, 1.97; 95% CI, 1.14-3.38) or more of hot temperature beverages was associated with higher risk of ESCC; HRs increased with increasing daily intake of hot temperature beverages (P-trend < 0.01). ESCC risk was still higher for those who drank very hot beverages; drinking ≤ 4 cups/d was associated with a 2.5-fold higher risk (HR, 2.52; 95% CI, 1.27-5.03), and risk increased with increasing daily intake of very hot temperature beverages (P-trend < 0.01). There was no clear association for EAC.

CONCLUSIONS

Our findings provide new evidence that drinking hot or very hot beverages is a risk factor for ESCC in the UK where drinking hot tea and coffee is common.

Population attributable fraction of dietary risk factors for cancer mortality with a focus on gastrointestinal cancers in a population based cohort study

Diet and nutrition are critical factors influencing cancer, the second leading cause of death worldwide. This study evaluated dietary risk factors and cancer mortality. 49,773 participants aged 40-75 years from the Golestan Cohort Study (GCS) were followed for a median of 15 years. Dietary intake was assessed using a validated food frequency questionnaire. Cox proportional hazard models estimated hazard ratios (HRs) and 95% confidence intervals (CIs), while population attributable fractions (PAFs) quantified the impact of reducing dietary risk factors. Low fruit intake accounted for 4.7% (95% CI: 0.5-8.7%) of all cancer deaths and 4.91% (95% CI: 0-9.85%) of male cancer deaths. It contributed to 23.5% (95% CI: 4.7-38.59%) of pancreatic cancer mortality in both sexes and 29.36% (95% CI: 5.15-47.38%) of male pancreatic cancer deaths. Low omega-3 intake increased esophageal and gastric cancer mortality risks, with PAFs of 21.65% (95% CI: 1.14-37.9%) and 21.46% (95% CI: 2.81-36.53%), respectively. In females, low omega-3 intake accounted for 38.68% (95% CI: 4.05-60.81%) of gastric cancer deaths. Low fruit and omega-3 consumption elevated cancer mortality risk. Community- and individual-level interventions are essential to enhance nutrient intake and reduce cancer mortality.

Can nutritional scores improve the WHO calibrated non-laboratory risk prediction model for cardiovascular disease? Golestan Cohort Study

Purpose

Evaluation of the added value of Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diet scores on the prediction model of the World Health Organization (WHO) to predict 10-year cardiovascular disease (CVD) mortality using the Golestan Cohort Study data.

Methods

A total of 44,648 participants (25,268 women and 18,531 men) were included in the final analysis. To assess the external validity of the non-laboratory risk model of WHO, the Area Under the Curve (AUC) and calibration plot methods were used. The multivariate Cox proportional hazards regression analysis was used to evaluate the association of 10-year CVD mortality risk with DASH and Mediterranean scores and their components. The added value of each significant variables was evaluated by the concordance C-statistic and integrated discrimination improvement (IDI). Statistical significance was defined as p-value < 0.05.

Results

DASH and Mediterranean diet scores were not significant predictors of 10-year CVD mortality in both genders (p > 0.05). However, sodium and total vegetable in both genders and added sugar in women were significant predictors for 10-year stroke mortality (p < 0.05). Sodium intake in women and monounsaturated fatty acid (MUFA) to saturated fatty acid (SFA) ratio in men had significant associations with 10-year mortality of myocardial infarction/coronary heart disease (MI/CHD). Calculation of IDI showed that none of the evaluated nutritional indices/variables could significantly improve the WHO model performance and predictive ability.

Conclusion

Inclusion of DASH and Mediterranean diet scores and their components did not improve WHO risk prediction model performance and predictive ability to predict 10-year CVD mortality.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-024-01463-x.

Population attributable fractions of cancer mortality related to indoor air pollution, animal contact, and water source as environmental risk factors: Findings from the Golestan Cohort Study

BACKGROUND

Environmental risk factors are significant contributors to cancer mortality, which are neglected.

PURPOSE

This study aimed to estimate the population attributable fraction of cancer mortality due to the environmental risk factors.

METHODS

Golestan cohort study is a population-base cohort on 50045 participants between 40-75 with about 18 years of follow up. We detected 2,196 cancer mortality and applied a multiple Cox model to compute the hazard ratio of environmental risk factor on all cancer and cancer-specific mortality. The population attributable fraction was calculated, accordingly.

RESULTS

Biomass fuels for cooking, as an indoor air pollution, increased the risk of colorectal, esophageal, gastric cancer, and all-cancer mortality by 84%, 66%, 37%, and 17% respectively. Using gas for cooking, particularly in rural areas, could save 6% [Population Attributable Fraction: 6.36(95%CI: 1.82, 10.70)] of esophageal cancer, 3% [Population Attributable Fraction: 3.43 (0, 7.33)] of gastric cancer, and 6% [Population Attributable Fraction: 6.25 (1.76, 13.63)] of colorectal cancer mortality. Using a healthy tap water source could save 5% [Population Attributable Fraction:5.50(0, 10.93)] of esophageal cancer mortality, particularly in rural areas. There was no significant association between indoor air pollution for heating purposes and animal contact with cancer mortality.

CONCLUSION

Considering the results of this study, eliminating solid fuel for most daily usage, among the population with specific cancer types, is required to successfully reduce cancer related mortality. Adopting appropriate strategies and interventions by policymakers such as educating the population, allocating resources for improving the healthy environment of the community, and cancer screening policies among susceptible populations could reduce cancer related mortalities.

Kharameh cohort study (KHCS) on non-communicable diseases and preliminary findings of 3-year follow-up

PURPOSE

The Kharameh cohort study (KHCS) is one branch of the 'Prospective Epidemiological Research Studies in Iran', located in the south of Iran. The enrolment phase of KHCS spanned from April 2015 to March 2017, during which urban and rural residents of Kharameh were enrolled in the study. KHCS aims to investigate the incidence of non-communicable diseases (NCDs) such as hypertension, diabetes mellitus, cardiovascular diseases and cancer, and its related risk factors in a 15-year follow-up.

PARTICIPANTS

KHCS was designed to recruit 10 000 individuals aged 40-70 years old from both urban and rural areas of Kharameh. Thus, a total of 10 800 individuals aged 40-70 years of age were invited and, finally, 10 663 subjects were accepted to participate, with a participation rate of 98.7%.

FINDINGS TO DATE

Of the 10 663 participants, 5944 (55.7%) were women, and 6801 (63.7%) were rural residents. The mean age of the participants was 51.9±8.2 years. 41.8% of the participants were aged 40-49, 35.2% were aged 50-59 and the remaining 23% were 60-70 years old. Until March 2020 (first 3 years of follow-up), the total number of patients diagnosed with NCDs was 1565. Hypertension, type 2 diabetes and acute ischaemic heart disease were the most common NCDs. Furthermore, the total number of deaths during the first 3 years of follow-up was 312, with cardiovascular diseases (38.7%) as the most common cause of death, followed by cerebrovascular diseases (11.8%) and cancer (16.2%).

FUTURE PLANS

The remaining 12 years of follow-up will inevitably shed light on the genetic, lifestyle/socioeconomic status, and environmental risk and protective factors of NCDs.

Dental health and lung cancer risk in the Golestan Cohort Study

BACKGROUND

Poor oral health has been linked to various systemic diseases, including multiple cancer types, but studies of its association with lung cancer have been inconclusive.

METHODS

We examined the relationship between dental status and lung cancer incidence and mortality in the Golestan Cohort Study, a large, prospective cohort of 50,045 adults in northeastern Iran. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between three dental health measures (i.e., number of missing teeth; the sum of decayed, missing, or filled teeth (DMFT); and toothbrushing frequency) and lung cancer incidence or mortality with adjustment for multiple potential confounders, including cigarette smoking and opium use. We created tertiles of the number of lost teeth/DMFT score in excess of the loess adjusted, age- and sex-specific predicted numbers, with subjects with the expected number of lost teeth/DMFT or fewer as the reference group.

RESULTS

During a median follow-up of 14 years, there were 119 incident lung cancer cases and 98 lung cancer deaths. Higher DMFT scores were associated with a progressively increased risk of lung cancer (linear trend, p = 0.011). Compared with individuals with the expected DMFT score or less, the HRs were 1.27 (95% CI: 0.73, 2.22), 2.15 (95% CI: 1.34, 3.43), and 1.52 (95% CI: 0.81, 2.84) for the first to the third tertiles of DMFT, respectively. The highest tertile of tooth loss also had an increased risk of lung cancer, with a HR of 1.68 (95% CI: 1.04, 2.70) compared with subjects with the expected number of lost teeth or fewer (linear trend, p = 0.043). The results were similar for lung cancer mortality and did not change substantially when the analysis was restricted to never users of cigarettes or opium. We found no associations between toothbrushing frequency and lung cancer incidence or mortality.

CONCLUSION

Poor dental health indicated by tooth loss or DMFT, but not lack of toothbrushing, was associated with increased lung cancer incidence and mortality in this rural Middle Eastern population.

Incident cancers attributable to using opium and smoking cigarettes in the Golestan cohort study

Background

Opium consumption has recently been identified as a carcinogen, but the impact of opium use on cancer burden is unknown. We aimed to evaluate the fraction of cancers that could be attributed to opium use alone and in combination with cigarette smoking in a region where opium is widely used.

Methods

50,045 Iranian adults were recruited to this prospective cohort study between 2004 and 2008 and were followed through January 2022. We assessed the association between using opium and/or cigarette smoking and various cancers using proportional hazards regression models. We then calculated population attributable fractions (PAFs) for all cancers and for groups of cancers causally linked to opium and cigarette smoking.

Findings

Of the total participants, 8% only used opium, 8.3% only smoked cigarettes, and 9% used both substances. During a median 14 years of follow-up, 2195 individuals were diagnosed with cancer, including 215 opium-related cancers (lung, larynx, and bladder) and 1609 tobacco-related cancers (20 types). Opium use alone was estimated to cause 35% (95% CI: 26%-45%) of opium-related cancers, while smoking cigarettes alone was estimated to cause 9% (6%-12%) of tobacco-related cancers in this population. Using opium and/or cigarettes was estimated to cause 13% (9%-16%) of all cancers, 58% (49%-66%) of opium-related cancers, and 15% (11%-18%) of tobacco-related cancers. Moreover, joint exposure to opium and cigarettes had the greatest impact on cancers of the larynx, pharynx, lung, and bladder, with PAFs ranging from 50% to 77%.

Interpretation

Using opium and smoking cigarettes account for a large proportion of cancers in this population. To reduce the cancer burden, prevention policies should aim to decrease the use of both substances through public awareness campaigns and interventional efforts.

Funding

The Golestan Cohort Study work was funded by the Tehran University of Medical Sciences, Cancer Research UK, U.S. National Cancer Institute, International Agency for Research on Cancer. The presented analysis was supported by the International HundredK+ Cohorts Consortium (IHCC).

Diet Quality and Subsequent Incidence of Upper Gastrointestinal Cancers: Results from the Golestan Cohort Study

BACKGROUND

Recent evidence suggests overall diet quality, as assessed by dietary scores, may play a role in the development of upper gastrointestinal (UGI) cancers. However, the existing dietary scores are derived from high-income countries with different dietary habits than regions with the highest burden of UGI cancers, where limited data is available. This study aimed to investigate the association between overall diet quality and risk of esophageal and stomach cancers in a high-risk region for UGI cancers.

METHODS

We recruited 50045 individuals aged 40-75 between 2004-2008 from northeastern Iran and followed them annually through July 2020. Data on demographics, diet, and various exposures were collected using validated questionnaires. Diet quality was assessed by calculating the Healthy Eating Index (HEI), Alternative Healthy Eating Index (AHEI), Alternative Mediterranean Diet (AMED), Dietary Approaches to Stop Hypertension (DASH), and World Cancer Research Fund-American Institute for Cancer Research (WCRF-AICR) scores.

RESULTS

During an average 12 years of follow-up, 359 participants developed esophageal cancer and 358 developed stomach cancer. After adjustments, each standard deviation increase in baseline dietary scores was associated with up to 12% reduction in esophageal cancer risk and up to 17% reduction in stomach cancer risk. Esophageal cancer showed stronger inverse associations with adherence to AMED (HRQ4-vs-Q1=0.69 (0.49-0.98), P-trend=0.038). Stomach cancer showed stronger inverse correlation with WCRF-AICR (HRQ4-vs-Q1=0.58 (0.41-0.83), P-trend=0.004), and DASH (HRC4-vs-C1=0.72 (0.54-0.96), P-trend=0.041). These associations were comparable across different population subgroups. We did not observe significant associations between HEI and AHEI scores and UGI cancers in this population.

CONCLUSION

Despite the differences in consuming individual food groups, adherence to the available dietary recommendations (derived from high-income countries) was associated with lower risk for subsequent esophageal and gastric cancers in this high-risk population. Educating the public to have a healthy eating pattern might be an effective strategy towards prevention of UGI cancers in high-risk regions.

Human papillomavirus is an important risk factor for esophageal carcinoma in a Chinese population

PURPOSE

Different types of HPV have been associated with cancer in humans, but the role of HPV in esophageal cancer (EC) is controversial. The purpose of this study was to evaluate the correlation between HPV infection and EC in the Chinese population and to provide the scientific basis for the future prevention, control, early diagnosis, and treatment strategies of EC in China.

METHODS

PCR detected HPV infection in 1112 esophageal cancer tissue samples, and 89 HPV-positive samples were detected by genotyping. Proximity ligation assays (PLAs) and immunohistochemistry were used to detect the expression of HPV E6 and E7 proteins. Real-time fluorescent quantitative PCR was used to detect the integration of HPV16 E6. The level of HPV-specific antibody IgG in serum was detected by ELISA and PLA.

RESULTS

The positive rates of HPV L1, HPV16, HPV18, hpv16 + 18 E6 and hpv16/18 E6 in 1,112 EC tissue samples were 77.6%, 41.4%, 27.2%, 14.2% and 55.4% respectively. Multiple HPV subtypes were detected in HPV-positive EC samples. PLA showed that E6 and E7 were expressed in EC109 and formed complexes with p53 and pRb, respectively. Immunohistochemistry showed that the positive rates of hpv16 + 18 E6 and E7 in HPV-positive EC samples were 56.4% and 37.0%, respectively. HPV-DNA integration rate in HPV-positive EC tissues (88.79%) was higher than that in adjacent tissues (54.17%). HPV antibody was found in the serum of EC patients by a serological test.

CONCLUSION

The study suggests that HPV, especially HPV16 and HPV18, the infection may be a risk factor for EC in the Chinese population and that the E6 protein may play a key role in HPV-associated malignancies. These results may be important for the prevention and treatment of HPV-positive EC in China.

Polypill for prevention of cardiovascular diseases with focus on non-alcoholic steatohepatitis: the PolyIran-Liver trial

AIMS

Individuals with non-alcoholic steatohepatitis or elevated liver enzymes have increased cardiovascular mortality but are often excluded from prevention trials. We investigated the effectiveness of fixed-dose combination therapy for the prevention of major cardiovascular events (MCVE) among individuals with and without presumed non-alcoholic steatohepatitis (pNASH).

METHODS AND RESULTS

Two thousand four hundred participants over 50 were randomized into the intervention and control groups. Consent was obtained post-randomization. Consenting participants in the intervention group were given a pill containing aspirin, atorvastatin, hydrochlorothiazide, and valsartan (polypill). Participants were followed for 5 years. Presumed non-alcoholic steatohepatitis was diagnosed by ultrasonography and elevated liver enzymes. The primary outcome was MCVE. ClinicalTrials.gov: NCT01245608. Among the originally randomized population, 138 of 1249 in the intervention group (11.0%) and 137 of 1017 controls (13.5%) had MCVE during the 5-year follow-up [unadjusted risk ratio (RR) 0.83, 95% confidence interval (CI) 0.66-1.03]. Of the 1508 participants who consented to additional measurements and treatment, 63 of 787 (8.0%) intervention group participants and 86 of 721 (11.9%) controls had MCVE (adjusted RR 0.61, 95% CI 0.44-0.83). Although the adjusted relative risk of MCVE in participants with pNASH (0.35, 95% CI 0.17-0.74) was under half that for participants without pNASH (0.73, 95% CI 0.49-1.00), the difference did not reach statistical significance. There was no change in liver enzymes in participants taking polypill but among those with pNASH, there was a significant decrease after 60 months of follow-up (intragroup -12.0 IU/L, 95% CI -14.2 to -9.6).

CONCLUSION

Among patients consenting to receive fixed-dose combination therapy, polypill is safe and effective for the prevention of MCVE, even among participants with fatty liver and increased liver enzymes.

Opium use as an independent risk factor for pancreatic cancer: A case-control study

BACKGROUND

Pancreatic cancer (PC) is ranked as the seventh leading cause of cancer deaths worldwide. The current study was conducted to explore the correlation between the use of opium and its derivatives (opium) and PC in Iran.

METHODS

In this case-control study which was conducted in Kerman province, south east part of Iran; 176 patients with PC, and 352 healthy individuals as the control group were matched in terms of age, sex, and place of residence. A structured questionnaire including questions of opium usage, alcohol usage, cigarette smoking, and diet was used to collect the data. The relation between the use of opium and PC was adjusted for tobacco smoking, education, daily intake of fruit, vegetables, red meat, and hydrogenated fats and analyzed using the conditional logistic regression.

RESULTS

There was a positive relationship between the opium use and the increased risk of PC (Adjusted Odds Ratio (AOR) = 4.33, 95 % CI: 2.09-8.95), which was even stronger than its association with cigarette smoking (AOR = 1.67, 95 % CI: 0.86-3.24), although their difference was not statistically significant. A significant dose-response relation was detected between the use of opium; as the relation was stronger in heavy users (AOR low users = 4.93, 95 % CI: 1.79-13.54 and AOR heavy users = 5.10, 95 % CI: 2.10-12.35). Moreover, PC was higher among participants starting the use of opium at a younger age than those who started opium at an older age (AOR = 8.03, 95 % CI: 3.19-20.23).

CONCLUSION

This study demonstrated that opium use is associated with a high and strong risk of PC as an independent risk factor. Further studies should be done to reduce the use of opium in Iran and other world countries.

Oral Health and Risk of Upper Gastrointestinal Cancers in a Large Prospective Study from a High-risk Region: Golestan Cohort Study

Tooth loss and periodontal disease have been associated with several cancers, and poor oral health may be an important risk factor for upper gastrointestinal (UGI, i.e., esophageal and gastric) cancers. We assessed the relationship between oral health and UGI cancers using a large prospective study of over 50,000 adults living in Golestan Province, Iran, a high-incidence area for these cancers. Hazard ratios (HRs) and 95% confidence intervals (CI) were estimated for the association between three different measures of oral health [frequency of tooth brushing; number of missing teeth; and the sum of decayed, missing, and filled teeth (DMFT)] and UGI cancers. During a median follow-up duration of 13 years, there were 794 incident UGI cancers (396 esophageal and 398 gastric cancers). Daily tooth brushing was associated with a decreased risk of developing both esophageal (HR = 0.670; 95% CI: 0.486-0.924) and gastric (HR = 0.741; 95% CI: 0.544-1.01) cancers (combined UGI cancer HR = 0.697; 95% CI: 0.558-0.871) compared with never brushing. Tooth loss in excess of the loess smoothed, age- and sex-specific median number of teeth lost was significantly associated with esophageal (HR = 1.64; 95% CI: 1.08-2.47) and gastric cancers (HR = 1.58; 95% CI: 1.05-2.38). There were some adverse associations between DMFT and UGI cancers but most were not statistically significant. These results suggest increased risk of developing UGI cancers among individuals with poor oral health, and those who do not perform regular oral hygiene. PREVENTION RELEVANCE: Poor oral health is associated with the risk of upper gastrointestinal cancers, and oral hygiene practices may help prevent these cancers.

Opium use reporting error in case-control studies: neighborhood controls versus hospital visitor controls

Background: There are relatively scant data to determine whether hospital visitors could serve as a proper source of controls in case-control studies of illicit drug use. The aim of this study was to evaluate using neighborhood versus hospital visitor controls in reporting opium use. Methods: We used data from 2 independent case-control studies of cancer in Iran. In the first study, controls were selected from neighborhoods of the patients. For the second one, controls were selected from among hospital visitors. In the latter study, hospital visitors were companions of the patients or others visiting the hospital for reasons other than disease treatment. We used stata (version 12; Stata Corp( for all analyses and with a significance level of 0.05. Results: Data from 616 of neighborhood controls and 414 of hospital visitor controls were analyzed. Opium point prevalence among men was significantly higher in hospital visitors than neighborhood controls (43.3% vs 32.2%; P = 0.047), while the prevalence of cigarette smoking was very similar in both control groups (46.3% vs 47.2%; P =.847). Using a logistic regression analysis, in an unadjusted analysis, neighborhood controls were less likely to report opium use in both genders, with (unadjusted OR = 0.77; 95% CI: 0.59,1). After adjusting for potential confounders, the differences of opium use between the 2 control groups became more pronounced (Adjusted OR = 0.26; 95% CI: 0.10, 0.69). Conclusion: Because of the similarity of reporting cigarette smoking among neighborhood controls but substantially lower reporting of opium use among them, we concluded that neighborhood controls underreport opium use-a sensitive question- and that using neighborhood control biases the findings in case-control studies. Hospital visitor controls may be more appropriate than neighborhood controls for case-control studies of illicit drugs.

Obesity and incident gastrointestinal cancers: overall body size or central obesity measures, which factor matters?

BMI does not reflect the location or amount of body fat. We aimed to investigate the role of general and central obesity measures in the prediction of incident gastrointestinal cancers. In this analysis of the Golestan Cohort Study, we included 47 586 cancer-free individuals followed for 12.3 years (IQR: 10.5-13.2). We investigated the association of obesity measures including BMI, waist circumference and waist-to-hip ratio (WHR) at enrollment and the incidence of esophageal, gastric, colorectal and pancreatic cancers. Cox proportional hazard models were used to estimate the association between covariates and gastrointestinal cancer risk. We observed no significant associations between obesity measures and incidence of the above-mentioned gastrointestinal cancers in men. In women, BMI, waist circumference and WHR were associated with significant reductions in the risk of esophageal squamous cell carcinoma (ESCC): hazard ratio (HR): 0.67 [95% confidence interval (CI): 0.56-0.81], HR: 0.71 (95% CI: 0.60-0.84) and HR: 0.80 (95% CI: 0.68- 0.94), respectively. In addition, WHR was associated with significantly increased risks for colorectal cancer (HR: 1.39, 95% CI: 1.08-1.78) and gastric cancer (HR: 1.24, 95% CI: 1.01-1.51) in women. In this study, statistically significant associations between obesity measures and incident esophageal, gastric and colorectal cancers were seen in women.

The burden and predisposing factors of non-communicable diseases in Mashhad University of Medical Sciences personnel: a prospective 15-year organizational cohort study protocol and baseline assessment

Background

The rising burden of premature mortality for Non-Communicable Diseases (NCDs) in developing countries necessitates the institutionalization of a comprehensive surveillance framework to track trends and provide evidence to design, implement, and evaluate preventive strategies. This study aims to conduct an organization-based prospective cohort study on the NCDs and NCD-related secondary outcomes in adult personnel of the Mashhad University of Medical Sciences (MUMS) as main target population.

Methods

This study was designed to recruit 12,000 adults aged between 30 and 70 years for 15 years. Baseline assessment includes a wide range of established NCD risk factors obtaining by face-to-face interview or examination. The questionnaires consist of demographic and socioeconomic characteristics, lifestyle pattern, fuel consumption and pesticide exposures, occupational history and hazards, personal and familial medical history, medication profile, oral hygiene, reproduction history, dietary intake, and psychological conditions. Examinations include body size and composition test, abdominopelvic and thyroid ultrasonography, orthopedic evaluation, pulse wave velocity test, electrocardiography, blood pressure measurement, smell-taste evaluation, spirometry, mammography, and preferred tea temperature assessment. Routine biochemical, cell count, and fecal occult blood tests are also performed, and the biological samples (i.e., blood, urine, hair, and nail) are stored in preserving temperature. Annual telephone interviews and repeated examinations at 5-year intervals are planned to update information on health status and its determinants.

Results

A total of 5287 individuals (mean age of 43.9 ± 7.6 and 45.9% male) were included in the study thus far. About 18.5% were nurses and midwives and 44.2% had at least bachelor’s degree. Fatty liver (15.4%), thyroid disorders (11.2%), hypertension (8.8%), and diabetes (4.9%) were the most prevalent NCDs. A large proportion of the population had some degree of anxiety (64.2%). Low physical activity (13 ± 22.4 min per day), high calorie intake (3079 ± 1252), and poor pulse-wave velocity (7.2 ± 1.6 m/s) highlight the need for strategies to improve lifestyle behaviors.

Conclusion

The PERSIAN Organizational Cohort study in Mashhad University of Medical Sciences is the first organizational cohort study in a metropolitan city of Iran aiming to provide a large data repository on the prevalence and risk factors of the NCDs in a developing country for future national and international research cooperation.

Household Fuel Use and the Risk of Gastrointestinal Cancers: The Golestan Cohort Study

BACKGROUND

Three billion people burn nonclean fuels for household purposes. Limited evidence suggests a link between household fuel use and gastrointestinal (GI) cancers.

OBJECTIVES

We investigated the relationship between indoor burning of biomass, kerosene, and natural gas with the subsequent risk of GI cancers.

METHODS

During the period 2004-2008, a total of 50,045 Iranian individuals 40-75 years of age were recruited to this prospective population-based cohort. Upon enrollment, validated data were collected on demographics, lifestyle, and exposures, including detailed data on lifetime household use of different fuels and stoves. The participants were followed through August 2018 with < 1 % loss.

RESULTS

During the follow-up, 962 participants developed GI cancers. In comparison with using predominantly gas in the recent 20-y period, using predominantly biomass was associated with higher risks of esophageal [hazard ratio (HR): 1.89; 95% confidence interval (CI): 1.02, 3.50], and gastric HR: 1.83; 95% CI: 1.01, 3.31) cancers, whereas using predominantly kerosene was associated with higher risk of esophageal cancer (HR: 1.84; 95% CI: 1.10, 3.10). Lifetime duration of biomass burning for both cooking and house heating (exclusive biomass usage) using heating-stoves without chimney was associated with higher risk of GI cancers combined (10-y HR: 1.14; 95% CI: 1.07, 1.21), esophageal (10-y HR: 1.19; 95% CI: 1.08, 1.30), gastric (10-y HR: 1.11; 95% CI: 1.00, 1.23), and colon (10-y HR: 1.26; 95% CI: 1.03, 1.54) cancers. The risks of GI cancers combined, esophageal cancer, and gastric cancer were lower when biomass was burned using chimney-equipped heating-stoves (strata difference p -values = 0.001 , 0.003, and 0.094, respectively). Duration of exclusive kerosene burning using heating-stoves without chimney was associated with higher risk of GI cancers combined (10-y HR: 1.05; 95% CI: 1.00, 1.11), and esophageal cancer (10-y HR: 1.14; 95% CI: 1.04, 1.26).

DISCUSSION

Household burning of biomass or kerosene, especially without a chimney, was associated with higher risk of some digestive cancers. Using chimney-equipped stoves and replacing these fuels with natural gas may be useful interventions to reduce the burden of GI cancers worldwide. https://doi.org/10.1289/EHP5907.

Alcohol consumption in Iran: A systematic review and meta-analysis of the literature

ISSUES

Alcohol production, marketing and consumption are illegal in Iran. This systematic review examines the lifetime and last 12-month prevalence of alcohol consumption among the general and young population in Iran.

APPROACH

We searched Web of Science, PubMed, Embase, Scopus and Iranian scientific databases (i.e. Scientific Information Database and Magiran) for relevant publications in English and Persian from inception to 12 May 2019. Following a random-effects meta-analysis, we estimated the pooled prevalence of alcohol consumption among the general population and young people (<30 years old). Meta-regression was used to identify potential sources of heterogeneity.

KEY FINDINGS

Of the 2400 identified records, 62 met the inclusion criteria. The overall pooled prevalence of lifetime alcohol consumption among the general population and young people was 13.0% [95% confidence intervals (CI) 10.0, 16.0]. The overall pooled prevalence of last 12-month alcohol consumption was 12.0% (95% CI 7.0, 18.0) for the general population and 15.0% (95% CI 9.0, 22.0) for young people. The prevalence of alcohol consumption varied from 0.03% to 68.0% in different regions, 0.3% to 66.6% among males and 0.2% to 21.0% among females.

IMPLICATIONS

Our findings highlight the need for public health surveillance of alcohol use in Iran.

CONCLUSION

These estimates show that, on average, one in eight people in the general population have ever consumed alcohol in Iran, indicating that alcohol consumption is not an uncommon practice in the country.

A prospective study of tea drinking temperature and risk of esophageal squamous cell carcinoma

Previous studies have reported an association between hot tea drinking and risk of esophageal cancer, but no study has examined this association using prospectively and objectively measured tea drinking temperature. We examined the association of tea drinking temperature, measured both objectively and subjectively at study baseline, with future risk of esophageal squamous cell carcinoma (ESCC) in a prospective study. We measured tea drinking temperature using validated methods and collected data on several other tea drinking habits and potential confounders of interest at baseline in the Golestan Cohort Study, a population-based prospective study of 50,045 individuals aged 40-75 years, established in 2004-2008 in northeastern Iran. Study participants were followed-up for a median duration of 10.1 years (505,865 person-years). During 2004-2017, 317 new cases of ESCC were identified. The objectively measured tea temperature (HR 1.41, 95% CI 1.10-1.81; for ≥60°C vs. <60°C), reported preference for very hot tea drinking (HR 2.41, 95% CI 1.27-4.56; for "very hot" vs. "cold/lukewarm"), and reported shorter time from pouring tea to drinking (HR 1.51, 95% CI 1.01-2.26; for <2 vs. ≥6 min) were all associated with ESCC risk. In analysis of the combined effects of measured temperature and amount, compared to those who drank less than 700 ml of tea/day at <60°C, drinking 700 mL/day or more at a higher-temperature (≥60°C) was consistently associated with an about 90% increase in ESCC risk. Our results substantially strengthen the existing evidence supporting an association between hot beverage drinking and ESCC.

Individual and Combined Effects of Environmental Risk Factors for Esophageal Cancer Based on Results From the Golestan Cohort Study

BACKGROUND & AIMS

Northeast Iran has one of the highest reported rates of esophageal squamous cell carcinoma (ESCC) worldwide. Decades of investigations in this region have identified some local habits and environmental exposures that increase risk. We analyzed data from the Golestan Cohort Study to determine the individual and combined effects of the major environmental risk factors of ESCC.

METHODS

We performed a population-based cohort of 50,045 individuals, 40 to 75 years old, from urban and rural areas across Northeast Iran. Detailed data on demographics, diet, lifestyle, socioeconomic status, temperature of drinking beverages, and different exposures were collected using validated methods, questionnaires, and physical examinations, from 2004 through 2008. Participants were followed from the date of enrollment to the date of first diagnosis of esophageal cancer, date of death from other causes, or date of last follow-up, through December 31, 2017. Proportional hazards regression models were used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for the association between different exposures and ESCC.

RESULTS

During an average 10 years of follow-up, 317 participants developed ESCC. Opium smoking (HR 1.85; 95% CI 1.18-2.90), drinking hot tea (≥60°C) (HR 1.60; 95% CI 1.15-2.22), low intake of fruits (HR 1.48; 95% CI 1.07-2.05) and vegetables (HR 1.62; 95% CI 1.03-2.56), excessive tooth loss (HR 1.66; 95% CI 1.04-2.64), drinking unpiped water (HR 2.04; 95% CI 1.09-3.81), and exposure to indoor air pollution (HR 1.57; 95% CI 1.08-2.29) were significantly associated with increased risk of ESCC, in a dose-dependent manner. Combined exposure to these risk factors was associated with a stepwise increase in the risk of developing ESCC, reaching a more than 7-fold increase in risk in the highest category. Approximately 75% of the ESCC cases in this region can be attributed to a combination of the identified exposures.

CONCLUSIONS

Analysis of data from the Golestan Cohort Study in Iran identified multiple risk factors for ESCC in this population. Our findings support the hypothesis that the high rates of ESCC are due to a combination of factors, including thermal injury (from hot tea), exposure to polycyclic aromatic hydrocarbons (from opium and indoor air pollution), and nutrient-deficient diets. We also associated ESCC risk with exposure to unpiped water and tooth loss.

Building cancer registries in a lower resource setting: The 10-year experience of Golestan, Northern Iran

INTRODUCTION

The Golestan population-based cancer registry (GPCR) was established in Golestan province, Northern Iran, within the Asian belt with predominance of upper-gastrointestinal cancers. We aimed to present the experiences of the registry in a resource-limited setting over the 10 years since its inception (2004-2013).

METHODS

The GPCR was established as a research project to enable sustainable funding. A clear plan was developed for use of the GPCR data. New primary cancers were registered based on international standards, indices of data quality were routinely assessed and age-standardized incidence rates (ASR) per 100,000 person-years calculated using IARC's CanReg-5 software.

RESULTS

Overall, 19807 new cancer cases were registered during the study period, an average of 1981 cases per annum, with overall ASR of 175.0 and 142.4 in males and females, respectively. The GPCR data suggested gastrointestinal and breast cancers as the most common malignancies in Golestan province. We observed increasing incidence rates of breast and colorectal cancers but declining trends of esophageal cancer. Overall, indices of data quality were within acceptable ranges.

CONCLUSIONS

The GPCR data have been included in IARC's Cancer Incidence in Five Continents series, were used in 21 research projects, and published as 30 research papers. The key ingredients for the successful establishment and maintenance of the GPCR included sustainable sources of funding, a clear action plan for the use of data as well as stakeholder cooperation across all areas of the registration. The GPCR may be considered as a model for planning population-based cancer registries in lesser-resourced settings.

Oral health and mortality in the Golestan Cohort Study

Background

Previous studies have found associations between oral health and mortality, but the majority of previous studies have been conducted in high-income countries.

Methods

We used data from the Golestan Cohort Study, a study of 50 045 people aged 40 to 75 years in north eastern Iran, recruited from January 2004 to June 2008. Tooth loss and decayed, missing and filled teeth (DMFT) were assessed by trained physicians. Frequency of tooth brushing and use of dentures were self-reported. Cause-specific mortality was ascertained through March 2014. We calculated hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the associations between the oral health variables, overall mortality and cause-specific mortality.

Results

Participants with the greatest tooth loss had increased overall mortality (HR 1.43; 95% CI: 1.28, 1.61) compared with those with the least tooth loss; similar estimates were observed for DMFT score. For cause-specific mortality, an increased risk of death was found for tooth loss and mortality from cardiovascular disease (HR 1.33; 95% CI: 1.13, 1.56), cancer (HR 1.30; 95% CI: 1.03, 1.65) and injuries (HR 1.99; 95% CI: 1.28, 3.09). The associations between oral health and injury mortality were strongly attenuated after exclusion of participants with comorbid conditions at baseline. No statistical interaction was found between denture use and tooth loss or DMFT on mortality.

Conclusions

Poor oral health appears to predict overall and cause-specific mortality in populations in economic transition. Investigation of the underlying mechanisms might provide an important contribution to reducing mortality.

Hazards of cigarettes, smokeless tobacco and waterpipe in a Middle Eastern Population: a Cohort Study of 50 000 individuals from Iran

BACKGROUND

There is limited information about the hazards of cigarettes, smokeless tobacco and waterpipe in the Middle East. The aim of this study was to determine the association between different types of tobacco use and earlier death in the Golestan Cohort Study.

METHODS

The Study includes 50 045 adults (aged 40-75 years) from north eastern Iran. The baseline questionnaire (2004-2008) assessed information about use of cigarettes, chewing tobacco (nass) and waterpipe. To assess the use of each type of tobacco compared with never tobacco users, we used Cox regression models adjusted for age, socioeconomic status, area of residence, education and other tobacco used, and stratified by sex, ethnicity and opium use.

RESULTS

17% of participants reported a history of cigarette smoking, 7.5% chewing tobacco (nass) and 1.1% smoking waterpipe, and these figures declined in the later birth cohorts. During a median follow-up of 8 years, 4524 deaths occurred (mean age 64.8+9.9 years). Current (HR=1.44; 95% CI 1.28 to 1.61) and former (HR=1.35; 95% CI 1.16 to 1.56) cigarette smokers had higher overall mortality relative to never tobacco users. The highest cigarette-associated risk was for cancer death among current heavy smokers (HR=2.32; 95% CI 1.66 to 3.24). Current nass chewing was associated with overall mortality (HR=1.16; 95% CI 1.01 to 1.34), and there was a 61% higher risk of cancer death in people chewing nass more than five times a day. We observed an association between the cumulative lifetime waterpipe use (waterpipe-years≥28) and both overall (HR=1.66; 95% CI 1.11 to 2.47), and cancer mortality (HR=2.82; 95% CI 1.30 to 6.11).

CONCLUSIONS

Regular use of cigarettes, smokeless tobacco and waterpipe were associated with the risk of earlier death (particularly from cancer) in our cohort.

International cancer seminars: a focus on esophageal squamous cell carcinoma

The International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI) have initiated a series of cancer-focused seminars [Scelo G, Hofmann JN, Banks RE et al. International cancer seminars: a focus on kidney cancer. Ann Oncol 2016; 27(8): 1382-1385]. In this, the second seminar, IARC and NCI convened a workshop in order to examine the state of the current science on esophageal squamous cell carcinoma etiology, genetics, early detection, treatment, and palliation, was reviewed to identify the most critical open research questions. The results of these discussions were summarized by formulating a series of 'difficult questions', which should inform and prioritize future research efforts.

The Combined Effects of Healthy Lifestyle Behaviors on All-Cause Mortality: The Golestan Cohort Study

BACKGROUND

Most studies that have evaluated the association between combined lifestyle factors and mortality outcomes have been conducted in populations of developed countries.

OBJECTIVES

The aim of this study was to examine the association between combined lifestyle scores and risk of all-cause and cause-specific mortality for the first time among Iranian adults.

METHODS

The study population included 50,045 Iranians, 40 - 75 years of age, who were enrolled in the Golestan Cohort Study, between 2004 and 2008. The lifestyle risk factors used in this study included cigarette smoking, physical inactivity, and Alternative Healthy Eating Index. The lifestyle score ranged from zero (non-healthy) to 3 (most healthy) points. From the study baseline up to analysis, a total of 4691 mortality cases were recorded. Participants with chronic diseases at baseline, outlier reports of calorie intake, missing data, and body mass index of less than 18.5 were excluded from the analyses. Cox regression models were fitted to establish the association between combined lifestyle scores and mortality outcomes.

RESULTS

After implementing the exclusion criteria, data from 40,708 participants were included in analyses. During 8.08 years of follow-up, 3,039 cases of all-cause mortality were recorded. The adjusted hazard ratio of a healthy lifestyle score, compared with non-healthy lifestyle score, was 0.68 (95% CI: 0.54, 0.86) for all-cause mortality, 0.53 (95% CI: 0.37, 0.77) for cardiovascular mortality, and 0.82 (95% CI: 0.53, 1.26) for mortality due to cancer. When we excluded the first two years of follow up from the analysis, the protective association between healthy lifestyle score and cardiovascular death did not change much 0.55 (95% CI: 0.36, 0.84), but the inverse association with all-cause mortality became weaker 0.72 (95% CI: 0.55, 0.94), and the association with cancer mortality was non-significant 0.92 (95% CI: 0.58, 1.48). In the gender-stratified analysis, we found an inverse strong association between adherence to healthy lifestyle and mortality from all causes and cardiovascular disease in either gender, but no significant relationship was seen with mortality from cancer in men or women. Stratified analysis of BMI status revealed an inverse significant association between adherence to healthy lifestyle and mortality from all causes, cardiovascular disease and cancer among non-obese participants.

CONCLUSION

We found evidence indicating that adherence to a healthy lifestyle, compared to non-healthy lifestyle, was associated with decreased risk of all-cause mortality and mortality from cardiovascular diseases in Iranian adults.

Esophageal Cancer in Golestan Province, Iran: A Review of Genetic Susceptibility and Environmental Risk Factors

Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor that is typically diagnosed only when the tumor has gained remarkable size, extended to peripheral tissues, and led to dysphagia. Five-year survival of advanced cancer is still very poor (19%), even with improved surgical techniques and adjuvant chemoradiation therapy. Therefore, early detection and prevention are the most important strategies to reduce the burden of ESCC. Our review will focus on the studies conducted in Golestan province, an area with a high prevalence of ESCC in northern Iran. We review three aspects of the research literature on ESCC: epidemiological features, environmental factors (including substance abuse, environmental contaminants, dietary factors, and human papillomavirus [HPV]), and molecular factors (including oncogenes, tumor suppressor genes, cell cycle regulatory proteins, and other relevant biomarkers). Epidemiological and experimental data suggest that some chemicals and lifestyle factors, including polycyclic aromatic hydrocarbons (PAHs), cigarette smoking, opium use, and hot tea drinking are associated with the development of ESCC in Golestan. HPV infects the esophageal epithelium, but so far, no firm evidence of its involvement in esophageal carcinogenesis has been provided. Some of these factors, notably hot tea drinking, may render the esophageal mucosa more susceptible to injury by other carcinogens. There are few studies at molecular level on ESCC in Golestan. Increasing awareness about the known risk factors of ESCC could potentially reduce the burden of ESCC in the region. Further studies on risk factors, identifying high risk populations, and early detection are needed.

Pars cohort study of non-communicable diseases in Iran: protocol and preliminary results

OBJECTIVES

The pars cohort study (PCS) is a 10-year cohort study aiming to investigate the burden and the major risk factors of non-communicable diseases, and to establish a setting to launch interventions for prevention of these diseases and controlling their risk factors.

METHODS

All inhabitants of Valashahr district in South of Iran, aged 40-75 years, were invited to undergo interviews and physical examination, and to provide biological samples. A total of 9264 invitees accepted to participate in the study (95 % participation rate) and were recruited from 2012 to 2014. Active follow-up was also carried out after 12 months.

RESULTS

About 46 % of participants were male and 54 % were female. About 14.0 % of the participants were current smokers and 8.4 % were ever opium users. The prevalence of overweight and obesity were 37.3 and 18.2 %, respectively. The prevalence of hypertension was 26.9 %. A total of 49 participants died during a median follow-up of one year.

CONCLUSIONS

PCS with its large scale and wealth of socio-economic and medical data can be a unique platform for studying the etiology of non-communicable diseases and effective interventions in Iran.

Maternal haemoglobin concentrations before and during pregnancy and stillbirth risk: a population-based case-control study

Background

Results of previous studies on the association between maternal haemoglobin concentration during pregnancy and stillbirth risk are inconclusive. It is not clear if haemoglobin concentration before pregnancy has a role. Using prospectively collected information from pre-pregnancy and antenatal visits, we investigated associations of maternal haemoglobin concentrations before and during pregnancy and haemoglobin dilution with stillbirth risk.

Methods

In a population-based case–control study from rural Golestan, a province in northern Iran, we identified 495 stillbirths (cases) and randomly selected 2,888 control live births among antenatal health-care visits between 2007 and 2009. Using logistic regression, we estimated associations of maternal haemoglobin concentrations, haemoglobin dilution at different stages of pregnancy, with stillbirth risk.

Results

Compared with normal maternal haemoglobin concentration (110–120 g/l) at the end of the second trimester, high maternal haemoglobin concentration (≥140 g/l) was associated with a more than two-fold increased stillbirth risk (OR = 2.31, 95 % CI [1.30–4.10]), while low maternal haemoglobin concentration (<110 g/l) was associated with a 37 % reduction in stillbirth risk. Haemoglobin concentration before pregnancy was not associated with stillbirth risk. Decreased haemoglobin concentration, as measured during pregnancy (OR = 0.61, 95 % CI [0.46, 0.80]), or only during the second trimester (OR = 0.75, 95 % CI [0.62, 0.90]), were associated with reduced stillbirth risk. The associations were essentially similar for preterm and term stillbirths.

Conclusions

Haemoglobin concentration before pregnancy is not associated with stillbirth risk. High haemoglobin level and absence of haemoglobin dilution during pregnancy could be considered as indicators of a high-risk pregnancy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-0924-x) contains supplementary material, which is available to authorized users.

Multimorbidity: Epidemiology and Risk Factors in the Golestan Cohort Study, Iran: A Cross-Sectional Analysis

Advances in medicine and health policy have resulted in growing of older population, with a concurrent rise in multimorbidity, particularly in Iran, as a country transitioning to a western lifestyle, and in which the percent of the population over the age of 60 years is increasing. This study aims to assess multimorbidity and the associated risk factors in Iran. We used data from 50,045 participants (age 40-75 y) in the Golestan Cohort Study, including data on demographics, lifestyle habits, socioeconomic status, and anthropometric indices. Multimorbidity was defined as the presence of 2 or more out of 8 self-reported chronic conditions, including cardiovascular diseases, diabetes, chronic obstructive pulmonary disease, chronic kidney disease, liver disease, gastroesophageal reflux disease, tuberculosis, and cancer. Multivariate logistic regression models were used to examine the associations between multiple different factors and the risk factors. Multimorbidity prevalence was 19.4%, with the most common chronic diseases being gastroesophageal reflux disease (76.7%), cardiovascular diseases (72.7%), diabetes (25.3%), and chronic obstructive pulmonary disease (21.9%). The odds of multimorbidity was 2.56-fold higher at the age of >60 years compared with that at <50 years (P < 0.001), and 2.11-fold higher in women than in men (P < 0.001). Other factors associated with higher risk of multimorbidity included non-Turkmen ethnicity, low education, unemployment, low socioeconomic status, physical inactivity, overweight, obesity, former smoking, opium and alcohol use, and poor oral health. Apart from advanced age and female sex, the most important potentially modifiable lifestyle factors, including excess body weight and opium use, and opium user, are associated with multimorbidity. Policies aiming at controlling multimorbidity will require a multidimensional approach to reduce modifiable risk factors in the younger population in developing countries alongside adopting efficient strategies to improve life quality in the older population.

Effect of intravenous patient controlled ketamine analgesiaon postoperative pain in opium abusers

Background:

Acutepostoperative pain is among the worst experience that patient scan undergo, and many analgesics have been used to suppress it; especially in chronic opium abusers. Ketamine is an N-methyl-D-aspartate antagonist analgesic, having both anesthetic and analgesic properties, which are not affected to the same extent in chronic opium abusers.

Objectives:

In this study, we assessed the analgesic effects of ketamine added to morphine as a patient-controlled analgesia method for acute pain management, compared with a placebo, inchronic maleopium abusers.

Patients and Methods:

After institutional review board approval for ethical considerations, a randomized double-blinded placebo controlled clinical trial was conducted. A total of 140 male patients aged 18-65 years, undergoing orthopedic surgery, were entered into the study after matching inclusion and exclusion criteria. All patients received the same anesthesia method; while the first group received ketamine (1mg/mL) and morphine (0.5 mg/mL) as a patient-controlled analgesia (70 patients), the second group received morphine (0.5 mg/mL) plus normal saline (70 patients). P value less than 0.05 was considered statistically significant.

Results:

The ketamine and morphine group of patients experienced less postoperative pain and required less postoperative rescue analgesia. However, the unwanted postoperative side effects were nearly the same; although increased levels of postoperative nausea and vomiting were observed in the ketamine and morphine group

Conclusions:

This study demonstrated improved analgesic effects after using intravenous patient controlled analgesia with ketamine on postoperative pain in opium abusers.

Opium use and risk of mortality from digestive diseases: a prospective cohort study

OBJECTIVES

Opium use, particularly in low doses, is a common practice among adults in northeastern Iran. We aimed to investigate the association between opium use and subsequent mortality from disorders of the digestive tract.

METHODS

We used data from the Golestan Cohort Study, a prospective cohort study in northeastern Iran, with detailed, validated data on opium use and several other exposures. A total of 50,045 adults were enrolled during a 4-year period (2004-2008) and followed annually until December 2012, with a follow-up success rate of 99%. We used Cox proportional hazard regression models to evaluate the association between opium use and outcomes of interest.

RESULTS

In all, 8,487 (17%) participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 474 deaths from digestive diseases were reported (387 due to gastrointestinal cancers and 87 due to nonmalignant etiologies). Opium use was associated with an increased risk of death from any digestive disease (adjusted hazard ratio (HR)=1.55, 95% confidence interval (CI)=1.24-1.93). The association was dose dependent, with a HR of 2.21 (1.57-3.31) for the highest quintile of cumulative opium use vs. no use (Ptrend=0.037). The HRs (95% CI) for the associations between opium use and malignant and nonmalignant causes of digestive mortality were 1.38 (1.07-1.76) and 2.60 (1.57-4.31), respectively. Increased risks were seen both for smoking opium and for ingestion of opium.

CONCLUSIONS

Long-term opium use, even in low doses, is associated with increased risk of death from both malignant and nonmalignant digestive diseases.

Association of tooth loss and oral hygiene with risk of gastric adenocarcinoma

Poor oral health and tooth loss have been proposed as possible risk factors for some chronic diseases, including gastric cancer. However, a small number of studies have tested these associations. We conducted a case-control study in Golestan Province, Iran, that enrolled 309 cases diagnosed with gastric adenocarcinoma (118 noncardia, 161 cardia, and 30 mixed-locations) and 613 sex, age, and neighborhood matched controls. Data on oral health were obtained through physical examination and questionnaire including tooth loss, the number of decayed, missing, and filled teeth, and frequency of tooth brushing. ORs and 95% confidence intervals (95% CI) were obtained using conditional logistic regression models adjusted for potential confounders. Standard one degree-of-freedom linear trend test and a multiple degree-of-freedom global test of the effect of adding oral hygiene variables to the model were also calculated. Our results showed apparent associations between tooth loss and decayed, missing, filled teeth (DMFT) score with risk of gastric cancer, overall and at each anatomic subsite. However, these associations were not monotonic and were strongly confounded by age. The results also showed that subjects who brushed their teeth less than daily were at significantly higher risk for gastric cardia adenocarcinoma ORs (95% CI) of 5.6 (1.6-19.3). We found evidence for an association between oral health and gastric cancer, but the nonmonotonic association, the relatively strong effect of confounder adjustment, and inconsistent results across studies must temper the strength of any conclusions.

The gastro-esophageal malignancies in Northern Iran research project: impact on the health research and health care systems in Iran

BACKGROUND

The Gastro-Esophageal Malignancies in Northern Iran (GEMINI) research project is an example of recent progress in health research in Iran. The original aim of this project was to identify etiologic factors and prevention measures for upper gastrointestinal cancers in Northern provinces of Iran, but its achievements have gone much beyond this initial goal.

METHODS

GEMINI consists of several projects including cancer registries, pilot studies, case-control studies, and the Golestan Cohort Study. GEMINI has been conducted through extensive collaborations between the Digestive Disease Research Center of Tehran University of Medical Sciences with other domestic and international health organizations. The achievements of GEMINI include producing new knowledge, introducing new research methods, developing and expanding health research and health care infrastructures, investing in human resources, and increasing the awareness and knowledge of policy makers and officials at all levels about the importance of chronic diseases in Iran's health priorities.

CONCLUSION

The success of GEMINI reveals the feasibility of large-scale health research studies in developing countries and serves as a successful model not only for health research in Iran, but also for similar research studies in other developing nations.

Risk factors for esophageal cancer in a low-incidence area of Brazil

CONTEXT AND OBJECTIVES Esophageal cancer is the eighth commonest type of cancer worldwide, occupying sixth place in terms of mortality. Smoking and alcohol use are known risk factors for this type of cancer. The aim here was to evaluate the risk factors for esophageal cancer in a low-incidence area. DESIGN AND SETTING Case-control study in Goiânia, with 99 cases of esophageal cancer and 223 controls. METHODS The variables were sociodemographic, dietary, occupational and lifestyle data. The sample was analyzed using the chi-square test, Mann-Whitney test and Mantel-Haenszel approach for multivariate analysis. Odds ratios (OR) were calculated with 5% significance and 95% confidence intervals. RESULTS The risk of esophageal cancer was higher in patients ≥ 55 years (OR = 1.95; P < 0.001). Patients from rural areas were at greater risk of esophageal cancer (OR = 4.9; P < 0.001). Smoking was a risk factor among the cases (OR = 3.8; P < 0.001), as was exposure to woodstoves (OR = 4.42; P < 0.001). The practice of oral sex was not a risk factor (OR = 0.45; P = 0.04). Consumption of apples, pears, vegetables, cruciferous vegetables and fruit juices were protective against esophageal cancer. CONCLUSION In a region in which the incidence of esophageal cancer is low, the most significant risk factors were exposure to woodstoves, smoking and living in rural areas.

Gastric atrophy and oesophageal squamous cell carcinoma: possible interaction with dental health and oral hygiene habit

BACKGROUND

Gastric fundal atrophy has been hypothesised to increase the risk of oesophageal squamous cell carcinoma (OSCC), but studies have shown inconsistent results.

METHODS

We measured serum pepsinogen I (PGI) and pepsinogen II (PGII) among 293 incident cases and 524 matched neighbourhood controls in a high-risk area of Northern Iran. Conditional logistic regression model was used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs).

RESULTS

After controlling for age, sex, residence area and other potential confounders, gastric atrophy (defined by a validated criterion, PGI <55 μg dl(-1)) was associated with a two-fold increased risk (OR=2.01, 95% CI: 1.18, 3.45) of OSCC in the absence of nonatrophic pangastritis (defined as PGII <11.8 μg dl(-1)). Stratification by PGII decreased the misclassification errors due to cancer-induced gastritis. Presence of both poor dental health, indicated by higher than median sum of decayed, missing, and filled teeth (DMFT score), and gastric atrophy further increased the risk of OSCC (OR=4.15, 95% CI: 2.04, 8.42) with relative excess risk due to interaction (RERI) of 1.47 (95% CI: -1.15, 4.1). Coexistence of poor oral hygiene habit with gastric atrophy elevated OSCC risk eight times (OR=8.65, 95% CI: 3.65, 20.46) and the additive interaction index was marginally statistically significant (RERI=4.34, 95% CI: -1.07, 9.76).

CONCLUSION

Gastric atrophy is a risk factor for OSCC, and poor dental health and oral hygiene habit may act synergistically in increasing the risk.

Opium could be considered an independent risk factor for lung cancer: a case-control study

BACKGROUND

Lung cancer is the leading cause of cancer-related death worldwide, and half of all incident lung cancers are believed to occur in the developing countries, including Iran.

OBJECTIVE

We investigated the association of opium with the risk of lung cancer in a case-control study.

METHODS

We enrolled 242 cases and 484 matched controls in this study. A questionnaire was developed, containing questions on basic demographic characteristics, as well as lifelong history of smoking cigarettes, exposure to passive smoking, opium use and alcohol consumption. For smoking cigarettes and opium and also oral opium intake frequency, duration and cumulative use were categorized into three groups: no use, low use and high use. Conditional logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Multivariate analysis in men showed that after adjusting for the effect of ethnicity, education and pack years of smoking cigarettes, smoking opium remained as a significant independent risk factor with an OR of 3.1 (95% CI 1.2-8.1). In addition, concomitant heavy smoking of cigarettes and opium dramatically increased the risk of lung cancer to an OR of 35.0 (95% CI 11.4-107.9).

CONCLUSION

This study demonstrated that smoking opium is associated with a high risk of lung cancer as an independent risk factor.

Opium use and mortality in Golestan Cohort Study: prospective cohort study of 50,000 adults in Iran

OBJECTIVES

To investigate the association between opium use and subsequent risk of death.

DESIGN

Prospective cohort study.

SETTING

The Golestan Cohort Study in north-eastern Iran collected detailed validated data on opium use and other exposures at baseline. Participants were enrolled between January 2004 and June 2008 and were followed to May 2011, with a follow-up success rate of over 99%.

PARTICIPANTS

50,045 participants aged 40-75 at baseline.

MAIN OUTCOMES

Mortality, all cause and major subcategories.

RESULTS

17% (n = 8487) of the participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 2145 deaths were reported. The adjusted hazard ratio for all cause mortality associated with ever use of opium was 1.86 (95% confidence interval 1.68 to 2.06). Opium consumption was significantly associated with increased risks of deaths from several causes including circulatory diseases (hazard ratio 1.81) and cancer (1.61). The strongest associations were seen with deaths from asthma, tuberculosis, and chronic obstructive pulmonary disease (11.0, 6.22, and 5.44, respectively). After exclusion of people who self prescribed opium after the onset of major chronic illnesses, the associations remained strong with a dose-response relation.

CONCLUSION

Opium users have an increased risk of death from multiple causes compared with non-users. Increased risks were also seen in people who used low amounts of opium for a long period and those who had no major illness before use.

Is opium a real risk factor for esophageal cancer or just a methodological artifact? Hospital and neighborhood controls in case-control studies

Background

Control selection is a major challenge in epidemiologic case-control studies. The aim of our study was to evaluate using hospital versus neighborhood control groups in studying risk factors of esophageal squamous cell carcinoma (ESCC).

Methodology/Principal Findings

We compared the results of two different case-control studies of ESCC conducted in the same region by a single research group. Case definition and enrollment were the same in the two studies, but control selection differed. In the first study, we selected two age- and sex-matched controls from inpatient subjects in hospitals, while for the second we selected two age- and sex-matched controls from each subject's neighborhood of residence. We used the test of heterogeneity to compare the results of the two studies. We found no significant differences in exposure data for tobacco-related variables such as cigarette smoking, chewing Nass (a tobacco product) and hookah (water pipe) usage, but the frequency of opium usage was significantly different between hospital and neighborhood controls. Consequently, the inference drawn for the association between ESCC and tobacco use did not differ between the studies, but it did for opium use. In the study using neighborhood controls, opium use was associated with a significantly increased risk of ESCC (adjusted OR 1.77, 95% CI 1.17–2.68), while in the study using hospital controls, this was not the case (OR 1.09, 95% CI 0.63–1.87). Comparing the prevalence of opium consumption in the two control groups and a cohort enrolled from the same geographic area suggested that the neighborhood controls were more representative of the study base population for this exposure.

Conclusions/Significance

Hospital and neighborhood controls did not lead us to the same conclusion for a major hypothesized risk factor for ESCC in this population. Our results show that control group selection is critical in drawing appropriate conclusions in observational studies.

History of upper gastrointestinal cancers in relatives: a community-based estimate

AIM

The present study aimed to evaluate the prevalence of positive family history of these cancers in a large population-based sample of Tehran province, capital of Iran.

BACKGROUND

Upper gastrointestinal (UGI) cancers (gastric and esophagus cancer) constitute a major health problem worldwide. A family history of cancer can increase the risk for developing cancer and recognized as one of the most important risk factors in predicting personal cancer risk.

PATIENTS AND METHODS

This study designed as a cross-sectional survey in general population (2006-2007) of Tehran province. Totally 7,300 persons (age > = 20 years) sampled by random sampling on the basis of the list of postal, of whom 6,700 persons agreed to participate (response rate 92%). Respondents were asked if any first-degree (FDR) or second-degree (SDR) relatives had gastric or esophageal cancer.

RESULTS

Totally, 6,453 respondents (48% male) entered to the study. The mean age of responders with positive FH was significantly higher than those with negative FH (P < 0.05). In total, 341 respondents (5.3%) reporting a history of UGI cancers in their relatives, 134(2.1%) in FDRs, and 207(3.2%) in SDRs.

CONCLUSION

Our findings showed that the reported prevalence of FH of UGI cancers was relatively low and varied by specific respondent characteristics such as age and sex. However, the estimates of prevalence presented here are likely to be conservative compared with actual prevalence because of self-reported data gathering.

Macronutrients, vitamins and minerals intake and risk of esophageal squamous cell carcinoma: a case-control study in Iran

Background

Although Iran is a high-risk region for esophageal squamous cell carcinoma (ESCC), dietary factors that may contribute to this high incidence have not been thoroughly studied. The aim of this study was to evaluate the effect of macronutrients, vitamins and minerals on the risk of ESCC.

Methods

In this hospital-based case-control study, 47 cases with incident ESCC and 96 controls were interviewed and usual dietary intakes were collected using a validated food frequency questionnaire. Data were modeled through unconditional multiple logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI), controlling for age, sex, gastrointestinal reflux, body mass index, smoking history (status, intensity and duration), physical activity, and education.

Results

ESCC cases consumed significantly more hot foods and beverages and fried and barbecued meals, compared to the controls (p < 0.05). After adjusting for potential confounders, the risk of ESCC increased significantly in the highest tertiles of saturated fat [OR:2.88,95%CI:1.15-3.08], cholesterol [OR:1.53, 95%CI: 1.41-4.13], discretionary calorie [OR:1.51, 95%CI: 1.06-3.84], sodium [OR:1.49,95%CI:1.12-2.89] and total fat intakes [OR:1.48, 95%CI:1.09-3.04]. In contrast, being in the highest tertile of carbohydrate, dietary fiber and (n-3) fatty acid intake reduced the ESCC risk by 78%, 71% and 68%, respectively. The most cancer-protective effect was observed for the combination of high folate and vitamin E intakes (OR: 0.02, 95%CI: 0.00-0.87; p < 0.001). Controls consumed 623.5 times higher selenium, 5.48 times as much β-carotene and 1.98 times as much α-tocopherol as the amount ESCC cases consumed.

Conclusion

This study suggests that high intake of nutrients primarily found in plant-based foods is associated with a reduced esophageal cancer risk. Some nutrients such as folate, vitamin E and selenium might play major roles in the etiology of ESCC and their status may eventually be used as an epidemiological marker for esophageal cancer in Iran, and perhaps other high-risk regions.

A pilot double-blind randomised placebo-controlled trial of the effects of fixed-dose combination therapy ('polypill') on cardiovascular risk factors

AIM

Our objective was to investigate the effects and tolerability of fixed-dose combination therapy on blood pressure and LDL in adults without elevated blood pressure or lipid levels.

METHODS

This was a double-blind randomised placebo-controlled trial in residents of Kalaleh, Golestan, Iran. Following an 8-week placebo run-in period, 475 participants, aged 50 to 79 years, without cardiovascular disease, hypertension or hyperlipidaemia were randomised to fixed-dose combination therapy with aspirin 81 mg, enalapril 2.5 mg, atorvastatin 20 mg and hydrochlorothiazide 12.5 mg (polypill) or placebo for a period of 12 months. The primary outcomes were changes in LDL-cholesterol, systolic and diastolic blood pressure and adverse reactions. Analysis was by intention-to-treat basis.

RESULTS

At baseline, there were differences in systolic blood pressure (6 mmHg). Taking account of baseline differences, at 12 months, polypill was associated with statistically significant reductions in blood pressure (4.5/1.6 mmHg) and LDL-cholesterol (0.46 mmol/l). The study drug was well tolerated, but resulted in the modest reductions in blood pressure and lipid levels.

CONCLUSION

The effects of the polypill on blood pressure and lipid levels were less than anticipated, raising questions about the reliability of the reported compliance. There is a case for a fully powered trial of a polypill for the prevention of cardiovascular disease.

Global patterns of cancer incidence and mortality rates and trends

While incidence and mortality rates for most cancers (including lung, colorectum, female breast, and prostate) are decreasing in the United States and many other western countries, they are increasing in several less developed and economically transitioning countries because of adoption of unhealthy western lifestyles such as smoking and physical inactivity and consumption of calorie-dense food. Indeed, the rates for lung and colon cancers in a few of these countries have already surpassed those in the United States and other western countries. Most developing countries also continue to be disproportionately affected by cancers related to infectious agents, such as cervix, liver, and stomach cancers. The proportion of new cancer cases diagnosed in less developed countries is projected to increase from about 56% of the world total in 2008 to more than 60% in 2030 because of the increasing trends in cancer rates and expected increases in life expectancy and growth of the population. In this review, we describe these changing global incidence and mortality patterns for select common cancers and the opportunities for cancer prevention in developing countries.

The changing face of esophageal cancer

The two main histological esophageal cancer types, adenocarcinoma and squamous cell carcinoma, differ in incidence, geographic distribution, ethnic pattern and etiology. This article focuses on epidemiology with particular reference to geographic and temporal variations in incidence, along with a review of the evidence supporting environmental and genetic factors involved in esophageal carcinogenesis. Squamous cell carcinoma of the esophagus remains predominantly a disease of the developing world. In contrast, esophageal adenocarcinoma is mainly a disease of western developed societies, associated with obesity and gastro-esophageal reflux disease. There has been a dramatic increase in the incidence of adenocarcinoma in developed countries in parallel with migration of both esophageal and gastric adenocarcinomas towards the gastro-esophageal junction.

Verbal autopsy: reliability and validity estimates for causes of death in the Golestan Cohort Study in Iran

Background

Verbal autopsy (VA) is one method to obtain valid estimates of causes of death in the absence of valid medical records. We tested the reliability and validity of a VA questionnaire developed for a cohort study in Golestan Province in northeastern Iran.

Method

A modified version of the WHO adult verbal autopsy was used to assess the cause of death in the first 219 Golestan Cohort Study (GCS) subjects who died. The GCS cause of death was determined by two internists who independently reviewed all available medical records. Two other internists (“reviewers”) independently reviewed only the VA answers and classified the cause of death into one of nine general categories; they repeated this evaluation one month later. The reliability of the VA was measured by calculating intra-reviewer and inter-reviewer kappa statistics. The validity of the VA was measured using the GCS cause of death as the gold standard.

Results

VA showed both good validity (sensitivity, specificity, PPV, and NPV all above 0.81) and reliability (kappa>0.75) in determining the general cause of death independent of sex and place of residence. The overall multi-rater agreement across four reviews was 0.84 (95%CI: 0.78–0.89). The results for identifying specific cancer deaths were also promising, especially for upper GI cancers (kappa = 0.95). The multi-rater agreement in cancer subgroup was 0.93 (95%CI: 0.85–0.99).

Conclusions

VA seems to have good reliability and validity for determining the cause of death in a large-scale adult follow up study in a predominantly rural area of a middle-income country.

Research on cancer prevention, detection and management in low- and medium-income countries

The burden of cancer in low- and medium-income countries (LMIC) is expected to increase in the next decades. The application of current knowledge and results of research in key areas would contribute to limit the impact of this phenomenon. Opportunities for research on cancer prevention in LMIC include investigating specific circumstances of exposure to known carcinogens and to agents which are not prevalent in other regions, as well as interactions among carcinogens and between genetic and environmental factors. Early detection both by screening and early clinical diagnosis represents an important component of cancer control in LMIC. Research has been carried out to identify effective and sustainable approaches for early detection of cervical cancer through human papillomavirus testing and visual tests and of oral cancer through visual inspection. For other important neoplasms such as breast cancer, on the other hand, no effective low-cost screening methods are currently available. Downstaging represents a potentially important approach for cancer control and a priority area for future research. Studies addressing the efficacy of treatment protocols, country-specific cost-effectiveness of various interventions and the clinical utility and cost-effectiveness of innovative heath care and communication technologies represent the priority for clinical cancer research.

Candidate gene association study of esophageal squamous cell carcinoma in a high-risk region in Iran

There is a region with a high risk for esophageal squamous cell carcinoma (ESCC) in the northeast of Iran. Previous studies suggest that hereditary factors play a role in the high incidence of cancer in the region. We selected 22 functional variants (and 130 related tagSNPs) from 15 genes that have been associated previously with the risk of ESCC. We genotyped a primary set of samples from 451 Turkmens (197 cases and 254 controls). Seven of 152 variants were associated with ESCC at the P = 0.05 level; these single nucleotide polymorphisms were then studied in a validation set of 549 cases and 1,119 controls, which included both Turkmens and non-Turkmens. The association observed for a functional variant in ADH1B was confirmed in the validation set, and that of a tagSNP in MGMT, the association was borderline significant in the validation set, after correcting for multiple testing. The other 5 variants that were associated in the primary set were not significantly associated in the validation set. The histidine allele at codon 48 of ADH1B gene was associated with a significantly decreased risk of ESCC in the joint data set (primary and validation set) under a recessive model (odds ratio, 0.41; 95% confidence interval, 0.29-0.76; P = 4 x 10(-4)). The A allele of the rs7087131 variant of MGMT gene was associated with a decreased risk of ESCC under a dominant model (odds ratio, 0.79; 95% confidence interval, 0.64-0.96; P = 0.02). These results support the hypothesis that genetic predisposition plays a role in the high incidence of ESSC in Iran.