Neighborhood Controls Research Articles

Socio-economic status and oesophageal cancer: results from a population-based case–control study in a high-risk area

Cancer registries in the 1970s showed that parts of Golestan Province in Iran had the highest rate of oesophageal squamous cell carcinoma (OSCC) in the world. More recent studies have shown that while rates are still high, they are approximately half of what they were before, which might be attributable to improved socio-economic status (SES) and living conditions in this area. We examined a wide range of SES indicators to investigate the association between different SES components and risk of OSCC in the region. Data were obtained from a population-based case-control study conducted between 2003 and 2007 with 300 histologically proven OSCC cases and 571 matched neighbourhood controls. We used conditional logistic regression to compare cases and controls for individual SES indicators, for a composite wealth score constructed using multiple correspondence analysis, and for factors obtained from factors analysis. We found that various dimensions of SES, such as education, wealth and being married were all inversely related to OSCC. The strongest inverse association was found with education. Compared with no education, the adjusted odds ratios (95% confidence intervals) for primary education and high school or beyond were 0.52 (0.27-0.98) and 0.20 (0.06-0.65), respectively. The strong association of SES with OSCC after adjustment for known risk factors implies the presence of yet unidentified risk factors that are correlated with our SES measures; identification of these factors could be the target of future studies. Our results also emphasize the importance of using multiple SES measures in epidemiological studies.

Scrub typhus in Darjeeling, India: opportunities for simple, practical prevention measures

To identify risk factors for scrub typhus in Darjeeling, India, we compared 62 scrub typhus cases (acute fever with eschar and specific IgM) with 62 neighbourhood controls. Cases were more likely to live close to bushes [matched odds ratio (MOR) 10; 95% CI 2.3-63] and wood piles (MOR 3.5; 95% CI 1.5-9.5), to work on farms (MOR 10; 95% CI 2.7-63), to observe rodents at home (MOR 3.6; 95% CI 1.4-11) and at work (MOR 9; 95% CI 2.4-57), and to rear domestic animals (MOR 2.4; 95% CI 1.1-5.7). Cases were less likely to wash after work (MOR 0.4; 95% CI 0.1-0.9) and change clothes to sleep (MOR 0.2; 95% CI 0.1-0.5). A cleaner, rodent-controlled environment may prevent exposure to scrub typhus. Personal protection measures and better hygiene could further reduce individual risk.

Urinary tract infections and reduced risk of bladder cancer in Los Angeles

We investigated the association between urinary tract infections (UTIs) and transitional cell carcinoma of the bladder in a population-based case–control study in Los Angeles covering 1586 cases and age-, gender-, and race-matched neighbourhood controls. A history of bladder infection was associated with a reduced risk of bladder cancer among women (odds ratio (OR), 0.66; 95% confidence interval (CI), 0.46–0.96). No effect was found in men, perhaps due to power limitations. A greater reduction in bladder cancer risk was observed among women with multiple infections (OR, 0.37; 95% CI, 0.18–0.78). Exclusion of subjects with a history of diabetes, kidney or bladder stones did not change the inverse association. A history of kidney infections was not associated with bladder cancer risk, but there was a weak association between a history of other UTIs and slightly increased risk among men. Our results suggest that a history of bladder infection is associated with a reduced risk of bladder cancer among women. Cytotoxicity from antibiotics commonly used to treat bladder infections is proposed as one possible explanation.

Gated Streets and House Prices

We empirically examine the effect of neighborhood controls, including homeownerassociations and private/limited access streets, on house prices using data from St. Louis,one of the first urban areas in which such development patterns emerged. We find thathouses located in limited access subdivisions command an economically significant pricepremium holding other factors constant. We corroborate the size and economicsignificance of the price premium identified using data on three quite different suburbancommunities in Southern California. Findings are consistent with Tiebout sorting.

Tea drinking habits and oesophageal cancer in a high risk area in northern Iran: population based case-control study

Objective To investigate the association between tea drinking habits in Golestan province, northern Iran, and risk of oesophageal squamous cell carcinoma.Design Population based case-control study. In addition, patterns of tea...

Uso de servicios de planificación familiar de la Secretaría de Salud, poder de decisión de la mujer y apoyo de la pareja

To identify the influence of reproductive characteristics and women empowerment with the use of family planning services. Cases and non-cases design with neighborhood controls (147 users and 146 non-users of family planning services during 2003), in Guanajuato State, Mexico. Various indexes were constructed to evaluate women's empowerment and its relationship with family planning use. The use of family planning services was positively and significantly associated with the woman's power to make decisions (High: OR 3.2, CI95% 1.4-7.4), a high level of communication with her partner on contraceptive use (OR 3.5, CI95% 1.4-9.3); and a greater number of pregnancies (> 6 children: OR 4.4, CI95% 1.4-13.8). Factors such as a high level of female decision-making and more partner support for contraceptive use are related to the use of family planning services. Therefore, developing strategies that involve men and support female empowerment could contribute to increasing the use of family planning services.

Abstract A118: Tea drinking habits and esophageal cancer in a high risk area in Northern Iran

Abstract A118 Golestan Province in northern Iran is a high incidence area for oesophageal squamous cell carcinoma (ESCC). We investigated the association between tea drinking habits and risk of ESCC in a population-based case-control study conducted between 2003 and 2007 in Golestan, with 300 histologically-proven ESCC cases and 571 matched neighborhood controls. In addition, we measured tea temperature and tea drinking patterns among 48582 healthy participants in a cohort study in the same region. Nearly all (98%) of the cohort participants drank black tea regularly, with a mean volume of over one liter/day, and over 60% drank their tea at temperatures over 60°C. The results of the case-control study showed that compared to drinking lukewarm or warm tea, the OR (95% CI) for drinking hot tea was 2.07 (1.28-3.35) and for drinking very hot tea was 8.16 (3.93-16.9). Likewise, compared to drinking tea four or more minutes after pouring it, the ORs (95% CIs) for drinking tea 2-3 minutes and less than 2 minutes after pouring were 2.49 (1.62 - 3.83) and 5.41 (2.63 - 11.1), respectively. There was a strong agreement between responses to questions on temperature of tea drinking and time interval from pouring tea to drinking it (weighted kappa = 0.68). In conclusion, drinking hot tea, a habit commonly seen in Golestan Province, was strongly associated with higher risk of ESCC. Citation Information: Cancer Prev Res 2008;1(7 Suppl):A118.

Dairy products, leanness, and head and neck squamous cell carcinoma

As part of a population-based case-control study, we investigated the association of food groups and micronutrients estimated from a validated food frequency questionnaire (FFQ) with the risk of development of head and neck squamous cell carcinoma (HNSCC). Incident cases were accrued through Boston area hospitals from 1999 to 2003, and neighborhood controls were selected and matched by location, age, and sex. There were 504 cases and 717 controls enrolled, who completed the FFQ. We observed a positive association between the consumption of dairy products and HNSCC. The odds of HNSCC in the highest quintile of dairy intake was 1.64 (95% CI: 1.09-2.46), compared with subjects in the lowest quintile. There was a significant association between leanness with HNSCC. The odds of cancer among the leanest subjects was 5.8 (95%CI: 3.2-10.6) compared with a healthy BMI. Finally, intake of animal fat was positively associated with an elevation in cancer risk. The odds of HNSCC for high animal fat intake were 1.50 (0.99-2.27). Our data suggest that consumption of fruits and vegetables is not universally protective for HNSCC and that other food groups and nutrients may influence the risk for developing this disease.

Adjustment of Adolescents of Parents Living with HIV.

Family environment and rates of mental health and behavioral problems in HIV-negative adolescents and their parents living with HIV (PWH) were compared to adolescents and parents from non HIV-affected families living in similar inner-city neighborhoods. Adolescents and their parents were interviewed and a case-control sample was constructed. Data on sixty-two matched pairs of adolescents of PWH and those of neighborhood parents and forty-six matched pairs of PWH and HIV-negative parents were examined. Compared to neighborhood controls, adolescents of PWH experienced greater life stressors and family conflict and reported lower self-esteem. PWH reported greater emotional distress and substance use. However, there were no significant differences in emotional distress or externalized problem behaviors between the two adolescent groups. Clinical implications are discussed.

Water intake and bladder cancer risk in Los Angeles County

The overall evidence of an association between fluid intake and bladder cancer is not entirely consistent. We examined the fluid intake-bladder cancer relationship in the Los Angeles bladder cancer case-control study. A total of 1,586 cases and their age-, sex-, and race-matched neighborhood controls were interviewed in-person from 1987 to 1999. Information on total fluid intake was derived from the consumption of specific fluids including water, coffee, tea, alcohol, milk, juice, hot chocolate and soda. Total fluid intake was not associated with bladder cancer. Daily water intake was associated with a slight decrease in bladder cancer risk, with the protection more pronounced among women (p for trend = 0.039) than among men (p for trend = 0.62). Compared to drinking <1 glass of water per day, drinking > or =6 glasses/day was associated with 0.91 (95% confidence interval, 0.67-1.22) times the risk of bladder cancer among all subjects, 0.94 (0.67-1.32) times the risk among men, and 0.69 (0.36-1.33) times the risk among women. The water intake-bladder cancer association also seemed to be modified by daytime urination frequency with significant inverse association among subjects who urinated > or =6 times/day (p for trend = 0.015), but not among those who urinated less frequently. Similarly, the protection from water intake was confined to women who did not experience nocturia and to men who did. Results from our study suggest that water intake may be associated with a slight reduction in bladder cancer risk.

Haemophilus influenzae type b conjugate vaccine is highly effective in the Ugandan routine immunization program: a case–control study

To study the effectiveness of the Haemophilus influenzae type b (Hib) vaccination program in Uganda. Case-control study of Hib vaccine effectiveness against Hib meningitis. Cases were children hospitalized with Hib meningitis confirmed by culture and/or latex agglutination. Cases were identified retrospectively from July 2002 to July 2004, and prospectively from July 2004 to July 2005. Each case-patient was matched by age to three neighbourhood and three hospital controls; all children were eligible to receive Hib vaccine through the routine schedule. Vaccine effectiveness was evaluated by conditional logistic regression, controlling for confounding variables. We enrolled 41 cases; their median age was 6 months. Only six (15%) cases, all HIV-negative, had received >/=2 doses of Hib vaccine, compared with 64% of neighbourhood controls and 70% of hospital controls. Controlling for maternal education, the only variable which remained in the multivariable model, vaccine effectiveness for two or three doses vs. no dose was 99% [95% confidence intervals (CI) 92-100%] and 96% (95% CI 80-100%) when cases were compared with neighbourhood and hospital controls, respectively. In Uganda, Hib vaccine was highly effective in the context of the routine immunization schedule. Sustained routine use of Hib vaccine will contribute to the prevention of childhood morbidity and mortality.

Risk factors for typhoid fever in children in squatter settlements of Karachi: A nested case–control study

Typhoid fever remains a major public health problem in developing countries such as Pakistan. A great majority of cases occur in children living in poor sanitary conditions in squatter settlements in large cities. We conducted a case-control study to identify risk factor for typhoid fever in children under the age of 16 years residing in squatter settlements of Karachi. We enrolled 88 typhoid fever patients, diagnosed by positive blood culture or Typhidot test, between June 1999 and December 2001. Simultaneously, we enrolled 165 age-matched neighborhood controls. Multivariate analysis done through conditional binary logistic regression analysis technique showed that increasing number of persons in the household (odds ratio [OR]=1.9; 95% confidence interval [CI] 1.2-3.1), non-availability of soap near hand washing facility (OR=2.6; 95% CI 1.1-6.3), non-use of medicated soap (OR=11.2; 95% CI 1.3-97.6) and lack of awareness about contact with a known case of typhoid fever (OR=3.7; 95% CI 1.6-8.4) were independent risk factors of the disease. Health education with emphasis on hand washing may help decrease the burden of typhoid fever in developing countries.

The relative contribution of case management and inadequate care‐seeking behaviour to childhood deaths from diarrhoea and acute respiratory infections in Hidalgo, Mexico

Objective To investigate the contribution of poor case management and care-seeking behaviour to childhood deaths from acute respiratory infections (ARI) and diarrhoeal diseases in rural Mexico. Methods Eighty-nine deaths from ARI and diarrhoea in under-fives from Hidalgo over a 7-month period were identified from registered death certificates. We interviewed the carers of 75 of these children, eliciting what happened before death, including signs and symptoms, contact with health services, details on treatments and details of doctors. These death narratives were used to assess the contributions of care seeking and case management to the childhood deaths. We conducted an independent investigation of the clinical competence of doctors mentioned in the death narratives using standard case scenarios and compared this with results obtained from neighbourhood control doctors. Results Late care seeking and/or poor case management contributed to 68% of deaths. The estimated contribution of care seeking alone was 32%, of case management alone 17% and of both care seeking and case management 18% of deaths. Doctors implicated as having contributed to a child's death had significantly lower clinical competence scores than those who were not. Private doctors accounted for 1.4 times more consultations prior to death than public doctors, but were implicated in 1.8 times the number of deaths. Conclusion Efforts to reduce child mortality need to improve both care seeking for childhood illnesses and quality of case management. It is essential that doctors in the private sector be included, as in Mexico and many other countries they provide a large proportion of care, often with adverse outcomes.

Analgesics use and ESRD in younger age: a case-control study

BackgroundAn ad hoc peer-review committee was jointly appointed by Drug Authorities and Industry in Germany, Austria and Switzerland in 1999/2000 to review the evidence for a causal relation between phenacetin-free analgesics and nephropathy. The committee found the evidence as inconclusive and requested a new case-control study of adequate design.MethodsWe performed a population-based case-control study with incident cases of end-stage renal disease (ESRD) under the age of 50 years and four age and sex-matched neighborhood controls in 170 dialysis centers (153 in Germany, and 17 in Austria) from January 1, 2001 to December 31, 2004. Data on lifetime medical history, risk factors, treatment, job exposure and intake of analgesics were obtained in a standardized face-to-face interview using memory aids to enhance accuracy. Study design, study performance, analysis plan, and study report were approved by an independent international advisory committee and by the Drug Authorities involved. Unconditional logistic regression analyses were performed.ResultsThe analysis included 907 cases and 3,622 controls who had never used phenacetin-containing analgesics in their lifetime. The use of high cumulative lifetime dose (3rd tertile) of analgesics in the period up to five years before dialysis was not associated with later ESRD. Adjusted odds ratios with 95% confidence intervals were 0.8 (0.7 – 1.0) and 1.0 (0.8 – 1.3) for ever- compared with no or low use and high use compared with low use, respectively. The same results were found for all analgesics and for mono-, and combination preparations with and without caffeine. No increased risk was shown in analyses stratifying for dose and duration. Dose-response analyses showed that analgesic use was not associated with an increased risk for ESRD up to 3.5 kg cumulative lifetime dose (98 % of the cases with ESRD). While the large subgroup of users with a lifetime dose up to 0.5 kg (278 cases and 1365 controls) showed a significantly decreased risk, a tiny subgroup of extreme users with over 3.5 kg lifetime use (19 cases and 11 controls) showed a significant risk increase. The detailed evaluation of 22 cases and 19 controls with over 2.5 kg lifetime use recommended by the regulatory advisors showed an impressive excess of other conditions than analgesics triggering the evolution of ESRD in cases compared with controls.ConclusionWe found no clinically meaningful evidence for an increased risk of ESRD associated with use of phenacetin-free analgesics in single or combined formulation. The apparent risk increase shown in a small subgroup with extreme lifetime dose of analgesics is most likely an indirect, non-causal association. This hypothesis, however, cannot be confirmed or refuted within our case-control study. Overall, our results lend support to the mounting evidence that phenacetin-free analgesics do not induce ESRD and that the notion of "analgesic nephropathy" needs to be re-evaluated.

Environmental and Health-Related Risk Factors for Mycobacterium ulcerans Disease (Buruli Ulcer) in Benin

We conducted a case-control study to investigate the association between Buruli ulcer (BU) and environmental- and health-related behaviors in southern Benin. Hospital BU cases (N = 324) and sex- and age-matched neighborhood controls (N = 1,173) answered a questionnaire. Regular use of soap for washing, treating injuries with soap or antibiotic powder, and frequent contact with flowing water appeared protective against BU.

Long-Term Disability from Acute Childhood Japanese Encephalitis in Shanghai, China

We traced 85 Japanese encephalitis (JE) patients, 6-27 years after hospitalizations. The first control group was made up of 73 non-JE encephalitis patients 6-27 years previously, whereas the second control group was made up 78 neighborhood residents, matched to the 78 surviving JE cases by age, sex, and residence. All subjects were examined with neurologic examinations, intelligence quotient (IQ) measurement, Mini-Mental State Examinations (MMSE), and activities of daily living (ADL) assessments. At follow-up, 22% of JE patients had objective neurologic deficits compared with 3% of non-JE encephalitis patients. Moreover, 28% of JE patients had subnormal IQs, as opposed to 2% non-JE encephalitis patients. Abnormal ADL scores were only noted in 15% JE patients. All neighborhood controls had normal examination results, and one non-JE encephalitis case showed mildly reduced IQ. The study showed that significant neurologic and overall functional disability were evident in a high proportion of JE survivors many years after their index hospitalizations.

Intake of vitamin A-rich foods and lung cancer risk in Taiwan: with special reference to garland chrysanthemum and sweet potato leaf consumption.

A case-control study was conducted to investigate the association between the consumption of local common foods that are rich in vitamin A and the risk of lung cancer in Taiwan. A total of 301 incident lung cancer cases, 602 hospital controls, and 602 neighborhood controls were recruited. The consumption of 13 food items and vitamin supplements was estimated by use of a food frequency questionnaire. The conditional logistic regression models were used to estimate the adjusted odds ratios (AOR) and 95% confidence intervals (CI) for lung cancer risk with each control group as reference by adjustment of covariates. A reduced risk for lung cancer was found to be associated with increased intakes of vitamin A, alpha-carotene, and beta-carotene from 13 food items. More servings of vegetables (AOR for the highest versus the lowest quartile = 0.67-0.70, 95% CI = 0.42-1.08, (plinear trend )= 0.04), garland chrysanthemum (AOR for the highest versus the lowest tertile = 0.58-0.74, 95% CI = 0.37-1.14, (plinear trend )<= 0.04) and sweet potato leaves (AOR for the highest versus the lowest tertile = 0.43-0.65, 95% CI = 0.28-0.96, (plinear trend )<= 0.03) were associated with the reduced risk for lung cancer. In conclusion, higher consumption of vitamin A-rich vegetables, especially garland chrysanthemum and sweet potato leaves might provide potential protection from lung cancer.

The Effect of Acclydine in Chronic Fatigue Syndrome: A Randomized Controlled Trial

Objectives:It is unclear whether insulin-like growth factor (IGF) function is involved in the pathophysiology of chronic fatigue syndrome (CFS). Unpublished data and reports in patient organization newsletters suggest that Acclydine, a food supplement, could be effective in the treatment of CFS by increasing biologically active IGF1 levels. Here we aimed to measure the IGF1 and IGF binding protein (IGFBP) 3 status of CFS patients compared to age- and gender-matched neighborhood controls, and to assess the effect of Acclydine on fatigue severity, functional impairment, and biologically active IGF1 level (IGFBP3/IGF1 ratio).Design:A randomized, placebo-controlled, double-blind clinical trial.Setting:Radboud University Nijmegen Medical Centre, The Netherlands.Participants:Fifty-seven adult patients who fulfilled the US Centers for Disease Control and Prevention criteria for CFS. IGF status of 22 CFS patients was compared to that of 22 healthy age- and gender-matched neighborhood control individuals.Intervention:Acclydine or placebo for 14 wk.Outcome measures:Outcomes were fatigue severity (Checklist Individual Strength, subscale fatigue severity [CIS-fatigue]), functional impairment (Sickness Impact Profile-8 [SIP-8]), and biologically active IGF1 serum concentrations. Analyses were on an intention-to-treat basis.Results:There was no difference in IGF status in 22 CFS patients compared to healthy age- and gender-matched control individuals. Treatment with Acclydine did not result in significant differences compared with the placebo group on any of the outcome measures: CIS-fatigue +1.1 (95% CI −4.4 to +6.5, p = 0.70), SIP-8 +59.1 (95% CI −201.7 to +319.8, p = 0.65), and IGFBP3/IGF1 ratio −0.5 (95% CI −2.8 to +1.7, p = 0.63).Conclusion:We found no differences in IGF1 status in CFS patients compared to healthy matched neighborhood controls. In addition, the results of this clinical trial do not demonstrate any benefit of Acclydine over placebo in the treatment of CFS.

Recurrent multistate outbreak of Salmonella Newport associated with tomatoes from contaminated fields, 2005.

Salmonella Newport causes more than an estimated 100,000 infections annually in the United States. In 2002, tomatoes grown and packed on the eastern shore of Virginia contaminated with a pan-susceptible S. Newport strain caused illness in 510 patients in 26 states. In July-November 2005, the same strain caused illness in at least 72 patients in 16 states. We conducted a case-control study during the 2005 outbreak, enrolling 29 cases and 140 matched neighbourhood controls. Infection was associated with eating tomatoes (matched odds ratio 9.7, 95% confidence interval 3.3-34.9). Tomatoes were traced back to the eastern shore of Virginia, where the outbreak strain was isolated from pond water used to irrigate tomato fields. Two multistate outbreaks caused by one rare strain, and identification of that strain in irrigation ponds 2 years apart, suggest persistent contamination of tomato fields. Further efforts are needed to prevent produce contamination on farms and throughout the food supply chain.

Alcohol consumption and risk of bladder cancer in Los Angeles County

The role of alcoholic beverages in bladder carcinogenesis is still unclear, with conflicting evidence from different studies. We investigated the relationship between alcohol consumption and bladder cancer, and the potential interaction between alcohol consumption and other exposures. In a population-based case-control study conducted in Los Angeles County, 1,586 pairs of cases and their matched neighborhood controls were interviewed. Data were analyzed to determine whether bladder cancer risk differs by alcohol consumption, and whether different alcoholic beverages have different effects. The risk of bladder cancer decreased with increasing frequency (p for trend = 0.003) and duration of alcohol consumption (p for trend = 0.017). Subjects who drank more than 4 drinks per day had a 32% lower (odds ratio, 0.68; 95% confidence interval, 0.52-0.90) risk of bladder cancer than those who never drank any alcoholic beverage. Beer (p for trend = 0.002) and wine (p for trend = 0.054) consumption were associated with reduced risk of bladder cancer, while hard liquor was not. The reduction in risk was mostly seen among shorter-term smokers who urinated frequently. Alcohol consumption was strongly associated with a reduced risk of bladder cancer. The effect was modified by the type of alcoholic beverage, cigarette smoking and frequency of urination.