Dietary quercetin intake and risk of gastric cancer: results from a population-based study in Sweden.

BACKGROUND: To study the impact of the dietary antioxidant quercetin on risk of gastric adenocarcinoma. PATIENTS AND METHODS: Using data from a large Swedish population-based case-control study of gastric cancer (505 cases and 1116 controls), we studied the association between quercetin and risk of anatomic (cardia/noncardia) and histological (intestinal and diffuse) subtypes of gastric cancer. RESULTS: We found strong inverse associations between quercetin and the risk of noncardia gastric adenocarcinoma, with an adjusted odds ratio (OR) of 0.57 (95% confidence interval 0.40-0.83) for the highest quintile (≥11.9 mg) of daily quercetin intake relative to the lowest quintile of intake (<4 mg quercetin/day), supported by a significant decreasing linear trend (P value < 0.001). Similar findings were observed for the intestinal and diffuse subtype. For cardia cancer, we found a less evident and nonsignificant inverse relationship. The protection of quercetin appeared to be stronger among female smokers, with the OR leveled of at values <0.2 in quintiles 3-5 (>6 mg quercetin/day). CONCLUSIONS: High dietary quercetin intake is inversely related to the risk of noncardia gastric adenocarcinoma, and the protection appears to be particularly strong for women exposed to oxidative stress, such as tobacco smoking.

`Keeping Healthy in the Backseat': How Motherhood Interrupted HIV Treatment in Recently Delivered Women in Kenya

Although there is a large body of literature related to the experiences of motherhood and aspects of the change that it brings about; how the experience of motherhood affects the healthcare of women with chronic illness is less documented. This study explores how motherhood in newly delivered HIV-infected mothers in Kenya interrupted their antiretroviral treatment (ART). Qualitative interviews were performed with 26 mothers on ART in a rural or urban area. The data were organised and interpreted using content analysis. The study found that adherence to ART was influenced by contextual differences in socio-cultural expectations and family relationships. Urban life enabled women to make decisions on their own and to negotiate challenges that were often unpredictable. Women in rural areas knew what was expected of them and decisions were normally not for them to make alone. The women in Busia and Kibera had difficulties combining adherence with attaining the socio-cultural definition of good mothering. Lack of support from health providers and weak healthcare systems contributed to inadequate stocks of HIV drugs and inaccessibility of HIV-related care. From the data; we developed the main theme `keeping healthy in the backseat' and the two sub-themes `regaining self-worth through motherhood' and `mother first - patient later.' We suggest that motherhood is context-specific and follows socio-cultural practises; which made it difficult for the women in Kenya to follow ART instructions. There is a need to reassess HIV-related services for mothers on ART in order to give them a better chance to stay on treatment and satisfy their aspiration to be `good mothers.' Contextspecific HIV-treatment policies are necessary for ensuring adherence and successful treatment outcomes

The Dilemma of Safe Sex and Having Children: Challenges Facing HIV Sero-Discordant Couples in Uganda

Background: Sixty percent of new HIV infections in Uganda occur in stable relationships between HIV discordant couples. Given the importance of fertility in Uganda; we hypothesized that unsafe sexual practices may be used to found a family/replace a dead child. Thus; we explored sexual practices to understand to what extent these are influenced by the desire to have children and the implications for HIV transmission among discordant couples. Methods: A cross-sectional survey of 114 HIV discordant couples in Kampala; and in-depth interviews with 15 purposively selected couples. Quantitative data were analysed using STATA. Multivariate logistic regression analysis done to identify factors associated with consistent condom use. Thematic content analysis of qualitative data was done using NVIVO 2. Results: Participants wanting children and those with multiple sexual partners were less likely to use condoms (Adj OR 0.51; and 0.36 respectively). Three of the five types of sexual practices used by couples do not allow pregnancy to occur. Main reasons for wanting a child included: ensuring lineage continuity and posterity; securing relationships and pressure from relatives to reproduce. Challenges included: risk of HIV transmission to partner and child; lack of negotiating power for safer sex; failure of health systems to offer safe methods of reproduction. Conclusions: HIV sero-discordant couples with strong desire for childbearing have a dilemma of risking HIV infection or infecting their spouse. Some risk transmission of HIV infection to reproduce. We need to address gender issues; risky behaviour and reproductive health services for HIV sero-discordant couples

Reasons for unsatisfactory acceptance of antiretroviral treatment in the urban Kibera slum, Kenya.

The aim of this study was to explore why patients in the urban Kibera slum, Nairobi, Kenya, offered free antiretroviral treatment (ART) at the Médecins Sans Frontièrs (MSF) clinic, choose not to be treated despite signs of AIDS. Qualitative semi-structured interviews were conducted with 26 patients, 9 men and 17 women. Six main reasons emerged for not accepting ART: a) fear of taking medication on an empty stomach due to lack of food; b) fear that side-effects associated with ART would make one more ill; c) fear of disclosure and its possible negative repercussions; d) concern for continuity of treatment and care; e) conflicting information from religious leaders and community, and seeking alternative care (e.g. traditional medicine); f) illiteracy making patients unable to understand the information given by health workers.

Reasons, methods used and decision-making for pregnancy termination among adolescents and older women in Mulago Hospital, Uganda.

OBJECTIVE: To explore the methods, reasons and decision-making process for termination of pregnancy among adolescents and older women, in Mulago hospital, Kampala, Uganda. DESIGN: Comparative study. SUBJECTS: Nine hundred and forty two women seeking postabortion care, of which 333 had induced abortion (of whom 115 were adolescents). SETTING: The emergency gynaecological ward of Mulago Hospital, Kampala, Uganda from September 2003 through June 2004. RESULTS: Women with induced abortion were single, in polygamous marital relationships and of lower parity (p<0.001); had lower education and number of living children (p<0.05), reported more (p<0.001) mistimed, unplanned or unwanted pregnancies, and were 13 times more likely to have recent history of domestic violence. Relationship issues were the most common reason for pregnancy termination for both categories. Decision-making for induced abortion was influenced by socio-economic, educational and personal considerations. Instrumentation and use of local herbs in the genitalia were the most common methods for pregnancy termination. Neither methods used for pregnancy termination nor reasons differed when adolescents were compared with older women. CONCLUSION: Relationship issues influence the decision-making process for pregnancy termination. Neither methods used for pregnancy termination nor reasons for pregnancy termination differ when adolescents are compared with older women.

Helicobacter pylori in gastric cancer established by CagA immunoblot as a marker of past infection.

BACKGROUND & AIMS: Helicobacter pylori may disappear spontaneously with progressing precancerous changes and invalidate serologic studies of its association with gastric cancer. We reestimated the strength of the H. pylori-gastric cancer relationship, using both conventional immunoglobulin (Ig) G enzyme-linked immunosorbent assay (ELISA) and immunoblot (against cytotoxin-associated antigen A [CagA] antibodies that prevail longer after eradication) to detect past H. pylori exposure more relevant for time at cancer initiation. METHODS: In our population-based case-control study, the seroprevalence among 298 gastric adenocarcinoma cases was 72% (IgG ELISA) and 91% (immunoblot) vs. 55% and 56% among 244 controls frequency-matched for age and gender. RESULTS: Using IgG ELISA only, the adjusted OR for noncardia gastric cancer among H. pylori-positive subjects was 2.2 (95% confidence interval [CI], 1.4-3.6). When ELISA-/CagA+ subjects (odds ratio [OR], 68.0) were removed from the reference, the OR rose to 21.0 (95% CI, 8.3-53.4) and the previous effect modification by age disappeared. ELISA+/CagA- subjects had an OR of 5.0 (95% CI, 1.1-23.6). There were no associations with cardia cancer. CONCLUSIONS: The weaker H. pylori-cancer relationships in studies based on IgG ELISA rather than CagA may be caused by misclassification of relevant exposure. A much stronger relationship emerges with more accurate exposure classification. In the general Swedish population, 71% of noncardia adenocarcinomas were attributable to H. pylori.

Aspirin and risk for gastric cancer: a population-based case-control study in Sweden.

While aspirin and other non-steroid anti-inflammatory drugs (NSAIDs) are associated with gastric mucosal damage, they might reduce the risk for gastric cancer. In a population-based case-control study in 5 Swedish counties, we interviewed 567 incident cases of gastric cancer and 1165 controls about their use of pain relievers. The cases were uniformly classified to subsite (cardia/non-cardia) and histological type and information collected on other known risk factors for gastric cancer. Helicobacter pylori serology was tested in a subset of 542 individuals. Users of aspirin had a moderately reduced risk of gastric cancer compared to never users; odds ratio (OR) adjusted for age, gender and socioeconomic status was 0.7 (95% CI = 0.6-1.0). Gastric cancer risk fell with increasing frequency of aspirin use (P for trend = 0.02). The risk reduction was apparent for both cardia and non-cardia tumours but was uncertain for the diffuse histologic type. No clear association was observed between gastric cancer risk and non-aspirin NSAIDs or other studied pain relievers. Our finding lends support to the hypothesis that use of aspirin reduces the risk for gastric cancer.

Surgery for stomach cancer in a defined Swedish population: current practices and operative results. Swedish Gastric Cancer Study Group.

OBJECTIVE: To study routine surgical in-hospital care, and to relate postoperative morbidity and mortality to age, sex, tumour stage, operation done, and surgical workload of the hospital. DESIGN: Prospective population-based study. SETTING: All hospitals that diagnosed new cases of stomach cancer in five counties in central and northern Sweden, 1 February 1989-31 January 1995. PATIENTS: All 1024 patients diagnosed as having a new adenocarcinoma of the stomach. RESULTS: The stomach cancer was in such an advanced stage at diagnosis that only half of the patients could be offered a potentially curative operation. The tumour was resectable in 632 patients (62%). Distal gastric resection was done for 359 (57%) and total gastrectomy in 259 (41%) of all the resected cases. Postoperative complications occurred in 250 patients (31%). In multivariate analyses the relative risk (RR) for postoperative complications increased to 2.3 (95% confidence interval [CI] = 1.3 to 4.3) in patients over 79 years of age compared with those under 60. The corresponding RR for postoperative death was 5.1 (95% CI = 2.0 to 12.7) in patients over 79 years. Total gastrectomy combined with splenectomy and distal pancreatectomy carried the highest postoperative morbidity (RR = 3.3) and mortality (RR = 3.7) compared with distal gastrectomy. CONCLUSION: There was no difference in postoperative morbidity or mortality among different types of hospital categories. Surgical treatment of stomach cancer still carries a substantial morbidity and mortality in an unselected series of patients, particularly among elderly patients.

Employment as butcher and cancer risk in a record-linkage study from Sweden.

OBJECTIVE: To investigate the risk of cancer among butchers and other meat workers in a large record-linkage study from Sweden. METHODS: The Swedish Cancer Environment Register III contains nationwide data on cancer incidence during 1971-1989 for all residents, by occupation and industry of employment as reported at the 1960 and 1970 censuses. We identified 25,049 men classified as butchers or meat workers at either census. We used as a comparison group the remaining part of the active male population, after exclusion of workers with direct contact with animals. RESULTS: Butchers in the meat industry had a slight increase in the risk of cancer (relative risk [RR] 1.1, 95% confidence interval [CI] 1.0-1.3), which was due to an increased risk of cancers of the oral cavity and pharynx (RR 1.6, 95% CI 1.0-2.7), stomach (RR 1.6, 95% CI 1.1-2.7), larynx (RR 1.4, 95% CI 0.6-3.4), and lung (RR 1.4, 95% CI 1.1-1.9). The risk of stomach cancer was highest during the first 5 years of the study, and among butchers from urban areas. No temporal or geographic variations were seen for lung cancer risk, with elevations restricted to squamous cell carcinoma. An increased risk of stomach, laryngeal and lung cancers was present in butchers and meat workers outside the meat industry. There was no clear indication of an increased risk of other neoplasms. CONCLUSIONS: The increased risk of oral, laryngeal, lung and stomach cancers among Swedish butchers may be at least partly due to confounding by tobacco smoking, alcohol drinking, and other lifestyle factors. However, exposures in the meat industry (e.g., viruses, nitrosamines, polycyclic aromatic hydrocarbons) may contribute the elevated cancer risks.

Decreasing incidence of both major histologic subtypes of gastric adenocarcinoma--a population-based study in Sweden.

While the overall incidence of gastric cancer has fallen, presumably to a large extent in parallel with Helicobacter pylori infection, the occurrence of the diffuse histologic type is thought to have remained more stable, questioning the aetiologic role of H. pylori. We have analysed the incidence of the intestinal and diffuse types separately, while considering subsite (cardia/non-cardia). With an extensive prospective effort we identified all incident cases of gastric adenocarcinoma (n = 1337) in a well-defined Swedish population (1.3 million) 1989-1994. Tumours were uniformly classified histologically and topographically. Subgroup-specific incidence rates were computed and modelled using multivariate logistic regression. Site-specific trends were clearly discrepant. The overall incidence of adenocarcinoma distal to the gastric cardia declined by 9% (95% confidence interval 6-12%) per year, while cardia cancer remained stable. Thus, the feared rise in cardia cancer could not be confirmed despite clear site-specific trend discrepancies. The intestinal type predominated, especially in high-risk areas, while diffuse tumours prevailed among young patients and women. Both main histologic types of gastric adenocarcinoma declined markedly, at similar rapidity, and with no significant trend differences between the intestinal and diffuse types, even after multivariate adjustments. Our results are consistent with an aetiologic role of environmental factors including H. pylori also for diffuse-type gastric cancers.

Dietary antioxidant intake and the risk of cardia cancer and noncardia cancer of the intestinal and diffuse types: a population-based case-control study in Sweden.

In spite of diverging incidence trends, subsite, and subtype-specific gastric cancer data on the association with dietary antioxidants are sparse. We aimed to test whether the apparent protective effect of antioxidants is mainly confined to noncardia (distal) cancer of the intestinal subtype, to which most of the incidence decline in gastric cancer has been ascribed. In a Swedish study base (total population 1.3 million), we interviewed 567 cases uniformly classified to subsite (cardia vs. noncardia) and subtype (intestinal vs. diffuse), and 1165 population-based controls, frequency matched for age and sex. Serologic data on H. pylori status was available for a subset of 542 individuals. Ascorbic acid (vitamin C) was inversely associated with all subsites and subtypes of gastric cancer in a significant dose-response manner (all p<0.05), with risk reductions between 40% and 60%. beta-carotene was also strongly and negatively associated with risk, particularly with the intestinal type. The associations with alpha-tocopherol (vitamin E) were less clear. The highest parallel intake of all three antioxidants (quartiles 4), compared to those with the lowest parallel intakes (quartiles 1), was associated with a 70% lower risk of developing noncardia cancer (OR 0.3, 95% CI 0.1-0.9). Our results suggest that antioxidants might be especially beneficial among subjects at increased risk for gastric cancer such as smokers and those infected by H. pylori. We conclude that a high intake of antioxidants, as a consequence of high consumption of fruit and vegetables, may lower the risk not only for gastric cancer of the intestinal type, but also for diffuse type adenocarcinoma and cardia cancer.

Carcinoma of the gastric cardia: surgical practices and short-term operative results in a defined Swedish population.

Adenocarcinoma of the gastric cardia has one of the most rapidly increasing incidence rates of all tumors in Western countries. The aim of this population-based investigation was to study surgical practices and postoperative morbidity and mortality during routine hospital care. The study comprised 176 patients given a new diagnosis of adenocarcinoma of the gastric cardia from February 1, 1989 to the January 31, 1995 in five Swedish counties. The tumor was resectable in 100 (57%) patients (in 36% of the women and 64% of the men), but only 46% of all patients could be offered a potentially curative operation. A total gastrectomy was performed in 54 patients and a proximal gastric resection in 44. Postoperative complications occurred in 39%: in 20% of the patients under age 60 years and in 47% of those aged 60 and over (p = 0.006). Seventeen operated patients (13%) died before discharge. The hospital mortality increased from 3% among those < 60 years of age to 18% among those > 69 years (p = 0.041). Surgical treatment of carcinoma of the gastric cardia carries substantial morbidity and mortality. No important progress seems to have taken place since the 1960s.

Occupational exposures and risk of gastric cancer in a population-based case-control study.

Gastric cancer trends seem to follow improvements in the environment of blue-collar workers, but the etiological role of occupational exposures in gastric carcinogenesis is scantily investigated. The risk of gastric adenocarcinoma in 10 common occupational industries, and particularly the long-term effects of asbestos, organic solvents, impregnating agents, insecticides, and herbicides, were evaluated in a population-based case-control study, including data on most established risk factors. The study base included all individuals of ages 40-79, born in Sweden and living in either of two areas (total population, 1.3 million) with differing gastric cancer incidences, from February 1989 through January 1995. We interviewed 567 cases classified to site (cardia/noncardia) and histological type, and 1,165 population-based controls, frequency-matched for age and sex. Metal workers had a 46% excess gastric cancer risk [adjusted odds ratio (OR), 1.46; 95% confidence interval (CI), 1.10-1.94], increasing to 1.65 (95% CI, 1.17-2.32) for >10 years in the industry. The elevated risk after exposure to herbicides (OR, 1.56; 95% CI, 1.13-2.15) was attributable to phenoxyacetic acids (adjusted OR, 1.70; 95% CI, 1.16-2.48), similarly across tumor subtypes, and not modified by smoking, body mass index, or Helicobacter pylori. The absence of interaction was demonstrated by the pure multiplicative effect found among those exposed to both H. pylori and phenoxyacetic acids (OR, 3.42; 95% CI, 1.41-8.26). Organic solvents, insecticides, impregnating agents, and asbestos were not associated with gastric cancer risk. Employment in the metal industry and exposure to phenoxyacetic acids were both positively and independently associated with gastric cancer risk. The fractions of all gastric cancers attributable to these job-related exposures were small but not negligible (7 and 5%, respectively) in the Swedish population.

Tobacco, alcohol and the risk of gastric cancer by sub-site and histologic type.

Few studies have provided information on the role of smoking and alcohol in the carcinogenesis of gastric cancer by sub-site and histologic type. The relationship of snuff dipping with risk of gastric cancer has also been rarely studied. In a population-based case-control study conducted in 5 counties of Sweden from February 1989 to January 1995, a total of 90 cases of gastric cardia cancer, 260 and 164 cases of distal gastric cancer of intestinal and diffuse types, respectively, and 1164 frequency-matched control subjects were personally interviewed about life-time smoking, use of smokeless tobacco and use of alcohol 20 years ago. Current smokers had a higher risk than never-smokers for all 3 kinds of gastric adenocarcinoma [odds ratio (OR) 1.7, 95% confidence interval (CI) 1.0-3.1 for gastric cardia adenocarcinoma; OR 1.8, 95% CI 1.2-2.7 for distal gastric cancer of intestinal type; and OR 2.2, 95% CI 1.4-3.5 for distal gastric cancer of diffuse type], and the risk rose with increasing dose and duration of smoking among current smokers. However, no elevated risk was observed for ex-smokers. Neither intake of alcoholic beverages nor snuff dipping was associated with an increased risk of any type of cardia or gastric cancer. Our study did not support the hypothesis that the role of tobacco differs by sub-site and histologic sub-type of gastric cancer.

Evaluating gastric cancer misclassification: a potential explanation for the rise in cardia cancer incidence.

BACKGROUND: Reports of dramatic increases in gastric cardia cancer incidence warrant concern. However, the recent introduction of a separate diagnostic code, the lack of a consensus definition of the cardia area, and the accelerating interest in cardia cancer may affect classification practices. Little is known about the magnitude of cardia cancer misclassification in large cancer registries. METHODS: In a well-defined Swedish population (1.3 million), we uniformly classified all patients with newly diagnosed gastric adenocarcinoma (from 1989 through 1994) with respect to gastric subsite, and we used this patient group as our gold standard. We then evaluated the completeness of the Swedish Cancer Registry in registering gastric adenocarcinomas against this gold standard and, further, assessed the completeness of cardia cancer registration and the rate of falsely included cases to estimate the potential impact on observed incidence trends. RESULTS: Our gold standard contained 1337 case subjects with gastric adenocarcinoma. Overall, the Swedish Cancer Registry was 98% complete with regard to gastric adenocarcinomas and had a 4% rate of falsely included cases. The completeness of coding cardia cancer was only 69%, and the positive predictive value for cardia cancer was 82%, with no improvement over time. CONCLUSIONS: Although overall completeness of gastric cancer registration by the Swedish Cancer Registry was excellent, accuracy in registering cardia tumors was surprisingly low. Our estimates suggest that true cardia cancer incidence could be up to 45% higher or 15% lower than that reported in the Cancer Registry. This margin of error could accommodate the observed increase in cardia cancer in Sweden. Therefore, secular trends in cardia cancer incidence should be interpreted cautiously.