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J S Mandel

Publications and source records attributed to J S Mandel.

At least 37 records · Page 2Linked to original sources
PubMed1998

Folate intake, alcohol consumption, cigarette smoking, and risk of colorectal adenomas.

BACKGROUND: Recent evidence suggests that folic acid (and derivatives) could contribute to the protective effect of fruits and vegetables against the risk of large-bowel cancer. Other evidence indicates that alcohol drinking and cigarette smoking may impair the biologic actions of folate. We used data from an adenoma prevention trial to investigate the occurrence of colorectal adenomas (possible precursors of colorectal cancer) in association with folate intake, alcohol consumption, and cigarette smoking. METHODS: Patients with at least one recent large-bowel adenoma were followed with colonoscopy 1 year and 4 years after their qualifying colon examinations. Adenomas detected after the year 1 examination were used as end points. A food-frequency questionnaire was administered at study entry and at study completion; nutrient intake at study entry was used in this analysis. All statistical tests were two-sided. RESULTS: After adjustment for caloric intake, dietary folate had a significant protective association with the risk of recurrence of large-bowel adenoma (P for trend = .04). However, this inverse association was attenuated by further adjustment for intake of dietary fiber and fat. Use of folate supplements was not associated with a reduction in risk. Alcohol intake (seven or more drinks/week) was associated with increased risk (odds ratio = 2.04; 95% confidence interval = 1.28-3.26). Cigarette smoking, even smoking for long duration, was not related to adenoma recurrence. CONCLUSIONS: These data provide only modest support for previous findings suggesting beneficial effects of folate on colorectal adenoma risk. We find no evidence that cigarette smoking increases risk. These findings do suggest a substantial increase in risk with alcohol consumption.

Adenoma↗
PubMed1998

Mortality among United States radiologic technologists, 1926-90.

The possible mortality risk from low level chronic exposures to ionizing radiation was evaluated among 143,517 United States radiologic technologists certified by the American Registry of Radiologic Technologists between 1926-80. This is one of the few occupational studies of primarily women (73 percent) exposed to radiation during their employment. More than 2.8 million person-years of follow-up were accrued through 1990, and 7,345 deaths were identified. A strong healthy-worker effect was observed (standardized mortality ratios [SMR] for all causes and all cancers were 0.69 and 0.79, respectively). Lung cancer (429 deaths) was not increased with available measures of radiation exposure and no significant associations were observed for acute, myelogenous, and monocytic leukemia (74 deaths). Relative to the general population, the standardized mortality ratio (SMR) for female breast cancer was 0.99 (based on 425 deaths); however, breast cancer was significantly elevated relative to all other cancers in a test of homogeneity of SMRs (ratio of SMRs = 1.3, P < 0.0001). Significant risks were correlated with employment before 1940 (SMR = 1.5; 95 percent confidence interval [CI] = 1.2-1.9), when radiation doses were likely highest, and among women certified for more than 30 years (SMR = 1.4, CI = 1.2-1.7) for whom the cumulative exposure was likely greatest. Using an internal referent group, risk increased with duration of certification among the 1,890 women certified before 1940 (P-trend < 0.001). While the findings for breast cancer are consistent with a radiation effect, possible misclassification in exposure (based on number of years certified) and potential confounding associated with reproductive histories preclude a causal conclusion.

Adult↗
PubMed1998

An epidemiologic investigation of reproductive hormones in men with occupational exposure to perfluorooctanoic acid.

Perfluorooctanoic acid (PFOA), a potent synthetic surfactant used in industrial applications, is a peroxisome proliferator that has resulted in dose-related increases in hepatic, pancreatic acinar, and Leydig cell adenomas in laboratory animals. In addition, PFOA increased serum estradiol levels through the induction of hepatic aromatase activity. In 1993 and 1995, we conducted two cross-sectional studies of 111 and 80 production workers, respectively, and specifically measured their serum PFOA in relation to several reproductive hormones to determine whether such an effect occurs in humans. PFOA was not significantly associated with estradiol or testosterone in either year's study. A 10% increase in mean estradiol levels was observed among employees who had the highest levels of serum PFOA, although this association was confounded by body mass index. Neither was PFOA consistently associated with the other measured hormones. Our results provide reasonable assurance that, in this production setting, there were no significant hormonal changes associated with PFOA at the serum levels measured. Limitations of this investigation include its cross-sectional design, the few subjects exposed at the highest levels, and the lower levels of serum PFOA measured, compared with those levels reported to cause effects in laboratory animal studies.

Adult↗
PubMed1998

Dietary and supplemental calcium and the recurrence of colorectal adenomas.

The association between calcium intake and the risk of colorectal neoplasia remains controversial. This analysis prospectively investigated the association between dietary and supplemental calcium intake and recurrent colorectal adenomas. Participants were part of a multicenter, randomized clinical trial of antioxidant vitamins. The study endpoints were adenomas detected between surveillance colonoscopies conducted at approximately 1 year and 4 years after study entry. Baseline intake of energy-adjusted calcium derived from a food frequency questionnaire was used as the main exposure of interest. Calcium supplement use was assessed by semiannual questionnaires. Logistic regression was used to compute odds ratios and 95% confidence limits, and Poisson regression was used to estimate rate ratios. Subjects in the fifth quintile of dietary calcium had an adjusted odds ratio of 0.72 (95% confidence interval, 0.43-1.22) compared to those in the lowest quintile. Investigation of the numbers of adenomas yielded stronger findings: the rate ratio for the fifth quintile versus the first was 0.63 (95% confidence interval, 0.39-1.02). Dietary calcium seemed to have a greater effect among individuals with a high-fat diet than among those with a low-fat diet; however, the interaction was not statistically significant. Use of calcium supplements was not related to adenoma recurrence. These results suggest that a high calcium intake may be associated with a reduction in risk of recurrent adenomas, especially among individuals on a high-fat diet.

Adenoma↗
PubMed1997

Fecal occult blood screening in the Minnesota study: role of chance detection of lesions.

BACKGROUND: In the Minnesota Colon Cancer Control Study, annual fecal occult blood testing reduced mortality from colorectal cancer by at least 33.4%. Some attribute a large part of this reduction to chance detection of cancers by colonoscopies; rehydration of guaiac test slides greatly increased positivity and consequently the number of colonoscopies performed. This study was conducted to determine how much of the reduction resulted from chance detection. METHODS: We used a mathematical model developed by Lang and Ransohoff to estimate the proportion of the 33.4% mortality attainable by chance alone. Applying the model requires the specification of five parameters: duration of follow-up, rate of compliance with fecal occult blood testing, rate of compliance with colonoscopy, positivity rate, and efficacy of colonoscopy in reducing colorectal cancer mortality. We took values for four of the five parameters directly from the Minnesota study. For the fifth parameter, efficacy of colonoscopy, we selected a value of 60%, based on the conclusions of another study. Whereas the Lang-Ransohoff model selects persons for colonoscopy by chance alone, those with bleeding cancers would also be selected by sensitive fecal occult blood testing. We therefore adjusted the result of the Lang-Ransohoff model for this dual detectability. RESULTS: We found that 16%-25% of the reduction in colorectal cancer deaths effected by fecal occult blood testing in the Minnesota study was due to chance detection; the remainder was due to sensitive detection. CONCLUSION: Chance played a minor role in the detection of colorectal cancers by fecal occult blood testing in the Minnesota study.

Aged↗
PubMed1997

Fecal occult blood screening in the Minnesota study: sensitivity of the screening test.

BACKGROUND: In the Minnesota Colon Cancer Control Study, which used guaiac slides to annually screen stool samples for blood, mortality from colorectal cancer was reduced by 33.4%. The reported sensitivity of this test for colorectal cancer was about 90%. However, results from another study estimated the sensitivity to be 25%-33%; other investigators have reported intermediate values. Given these contradictions, we examined screening sensitivity for colorectal cancer in the Minnesota study by several direct and indirect methods. METHODS: In this reanalysis of data from the Minnesota study, we distinguished between sensitivity for colorectal cancer of the screening test (composed of six slides) and of the screening program (a series of such tests). We estimated screen sensitivity by adjusting the crude estimate from the final tests in each screening phase for colorectal cancer incidence in 5 years of follow-up, by modeling guaiac slide results at each screen as a function of the presence of occult blood, and by incorporating sensitive detection into a modification of a mathematical model developed by Lang and Ransohoff. Program sensitivity was estimated from the fraction of screen-detected cancers among all cancers diagnosed in screened individuals. RESULTS: The crude estimate of program sensitivity was 89.4%, whereas the modified Lang-Ransohoff model estimates screen sensitivities at 94.1%-96.2%, consistent with the estimates from the other methods. Indirect measures, such as the association between the number of positive slides among the six slides in each set and the positive predictivity for colorectal cancer, are consistent with these estimates. CONCLUSIONS: The Minnesota study reduced mortality from colorectal cancer through use of a screening test with average screen and program sensitivities of about 90%.

Colorectal Neoplasms↗
PubMed1997

Effects of brain injury on college academic performance.

Brain injury, a leading cause of mortality, morbidity and disability in the United States, has serious consequences and substantial costs. Although previous studies have assessed a variety of outcomes subsequent to brain injury, documentation of performance prior to brain injury using a case-control approach has not been included; preinjury performance differences may confound the estimate of the effects of brain injury on performance. The primary objective of this study was to compare academic performance before and after brain injury in a population of university undergraduate students to determine the extent to which the academic career of the brain-injured person was altered from what would have been expected in the absence of such an injury. Cases included all undergraduate students in a major university, between the ages of 17 and 27, who incurred a brain injury requiring hospitalization between 1980 and 1984 (n = 99). Two comparison groups were used to determine whether changes in academic performance were specifically related to brain injuries or injuries in general: (1) injured controls, i.e. 121 students between the ages of 17 and 27 years, hospitalized for injuries other than to the central nervous system, and (2) uninjured academic controls, i.e. 198 students with out injuries requiring hospitalization during the study period, matched 2:1 to the brain-injured students by age, gender, and completed course credits categorized as < 90, > or = 90. Although there were no differences when the total groups, including both males and females, were compared, there was a significant pre- to postinjury decrease in the grade point average for female cases when compared to their uninjured academic controls (p < 0.02). This difference was related to the effects of brain injury, and not to the effects of injury in general. No such difference was observed for the males. There were also no differences when the total groups, including males and females, were compared relevant to return to school. However, a significantly higher proportion of the female cases, compared with their uninjured academic controls, did not return to school after their injury; similar findings were identified for the injured controls as well. Thus, these differences were not specific to brain injury but rather to injury in general. In spite of this observation, the difference between female cases who returned and those who did not return was associated with neurological deficits, especially upper left limb motor deficits, as the time of hospital discharge. The findings from this effort are suggestive of gender differences in the consequences of brain injury and serve as a basis for further studies to evaluate the magnitude of this problem.

Adolescent↗
PubMed1997

A research agenda for AIDS prevention in the developing world.

BACKGROUND: In the developing world, HIV is spreading in many epidemiologic patterns, ranging from slow spread in limited segments of the population to exponential growth to mature epidemics. These differences are superimposed on widely varying cultures and patterns of behavior, creating unique challenges for prevention in each setting. Local prevention research is continually necessary to respond appropriately and effectively to local prevention needs and to best use scarce resources. THE RESEARCH AGENDA: We propose a research agenda for AIDS prevention in the developing world, consisting of three main components: epidemiologic and behavioral surveillance; enhancing local understanding of HIV risk behavior; and testing interventions. We review examples of each. This 'bottom-up' research is contrasted with 'top-down' research conducted in the developing world by scientists from developed countries to answer questions of general interest. RESULTS: The articles published in this volume exemplify the scope and importance of AIDS prevention research in the developing world. They also show what can be accomplished through international collaboration directed towards meeting local needs.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Traditional Balinese youth groups as a venue for prevention of AIDS and other sexually transmitted diseases.

OBJECTIVES: Our aims were to assess the feasibility of conducting peer-led educational interventions against AIDS and other sexually transmitted diseases (STDs) through traditional Balinese youth groups and to gather information on sexual risk-taking and its correlates among Balinese youth. DESIGN: A cross-sectional survey was conducted, with follow-up questionnaires for pilot intervention participants. SUBJECTS AND METHODS: A self-administered questionnaire was given to 375 subjects (aged 16-25 years) from 12 youth groups representing four main resort areas in Bali. Post-intervention data were collected from 97 of these subjects who had taken part in pilot educational programs. Focus groups supplemented survey data in evaluating the intervention and understanding risk behaviors. RESULTS: In a cross-sectional survey, one-quarter of males and few females reported sexual activity; subsequent focus groups suggested under-reporting by females. While knowledge and worries about HIV/AIDS were high, only 10% of sexually active males and no females reported consistent condom use. The mean age of first sexual intercourse was highly correlated with first alcohol consumption (P = 0.0003). Peer educators from selected youth groups planned and implemented interventions for their own groups. Post-intervention data indicated significant increases in communication about sexual issues with friends and parents. Condom attitudes became less negative and efficacy increased. Participants reported this as a first experience with peer-led health education, preferred interactive activities to adult-led lectures and recommended follow-up educational sessions. CONCLUSIONS: Peer educators from traditional youth groups can plan and conduct prevention programs for HIV/STDs that are well-received by their group memberships. Using such venues may be an efficient way to reach a wide range of pre-sexual Balinese youth, as well as those already at risk for HIV/STD due to unprotected sex, alcohol consumption and multiple sexual partners.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Adolescent sexual behavior along the Trans-Africa Highway in Kenya.

OBJECTIVE: To describe the demographic characteristics and HIV-related risk behaviors of adolescents frequenting truck stops along the Trans-Africa Highway in Kenya. METHODS: A cross-sectional study of 200 adolescents (52% female) aged 15-19 years was conducted at the Malaba, Sachangwan and Mashinari truck stops in Kenya. A standardized questionnaire assessing the adolescents' demographic characteristics and sexual behavior was administered. RESULTS: Most (89%) of the adolescents interviewed were out of school. Their median monthly family income was Ksh1000 (US$25). Most felt that their families provided inadequate access to food (72%), clothing (70%) and pocket money (87%). Ninety-three per cent of girls and 87% of boys had ever had sexual intercourse and of these 54% of girls and 38% of boys had ever used a condom. Fifty-two per cent of the girls and 30% of the boys reported ever having had a sexually transmitted disease. Forty-six percent of girls reported usually having sex with truck drivers, 78% of girls reported usually exchanging sex for gifts or money and 59% of boys reported usually giving gifts or money for sex. Subjects engaging in these three risk behaviors were generally less likely to be in school, less likely to live with relatives and less likely to report getting along well with their parents. CONCLUSION: Adolescents at truck stops along the Trans-African Highway in Kenya appear to be at significant risk for HIV infection. In the absence of an immediate and wide-ranging intervention, these conditions are likely to facilitate the spread of HIV from truck drivers and sex workers to adolescents.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Extremely low awareness of AIDS, sexually transmitted diseases and condoms among Dai ethnic villagers in Yunnan province, China.

OBJECTIVE: To assess the awareness of AIDS, other sexually transmitted diseases (STDs), condoms, sources of health information and HIV-related societal risks among Dai villagers in southern Yunnan Province, China. SUBJECTS AND METHODS: In November-December 1994, a cross-sectional descriptive study, comprising a questionnaire-based survey and focus group discussions, was conducted in three Dai villages in Mengla county; a total of 177 Dai villagers were interviewed in the survey and eight focus group discussions were held. Ethnographic observations provided a composite picture of HIV risks in the area. RESULTS: Only 18% of respondents had heard of AIDS, and only 25 and 28%, respectively, had heard of STDs or condoms. Furthermore, among these more aware groups, the level of knowledge was low and misconceptions were common. An ability to understand the official language (Mandarin) was the most important predictor of awareness of AIDS, other STDs or condoms. The sources of information in the three Dai villages sampled included TV, videos, radio and magazines, but only TV and videos had a large audience. Even so, these media were mostly in Mandarin and were not used in AIDS education. Travel outside of China was frequent; most villagers (77%) had traveled to Laos and 9% had traveled to Thailand. Societal risks of HIV transmission, such as an increasing incidence of STDs and an active sex industry, were observed in this area. CONCLUSIONS: Dai villagers in southern Yunnan Province had an extremely low awareness and knowledge of AIDS, other STDs and condoms. Given the high mobility of ethnic villagers to neighboring countries in Southeast Asia and the societal risks of HIV transmission in this area, there is an urgent need to provide accessible education about AIDS and other STDs. Suggestions regarding such health education and the implications of HIV policy-making are discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1997

HIV risk behavioral surveillance in Bangkok, Thailand: sexual behavior trends among eight population groups.

OBJECTIVE: To assess trends in HIV risk behaviors over a 3-year period in eight population groups in Bangkok, Thailand. DESIGN AND SUBJECTS: Using a repeated cross-sectional survey design with a structured questionnaire, we collected five sets of self-reported sexual behavior data related to HIV risk from the following subject groups at the same sampling sites during 1993-1996: direct and indirect female sex workers, male attenders of sexually transmitted disease (STD) clinics, female attenders of antenatal care clinics, male and female vocational students, and male and female factory workers. RESULTS: Reported patronage of commercial sex by the three male groups declined by an overall average of 48% over the 3-year period. Other non-regular sexual partnerships declined among male STD clinic attenders and vocational students. Condom use during most recent sexual intercourse between sex workers and clients peaked at high levels (>90%) in the early data waves, while among indirect sex workers and their clients, consistent condom usage increased from 56% to 89%. Low condom use persisted among sex workers and their non-paying sex partners. Single women reported low levels of sexual activity and condom use with no signs of an increase. Similarly, married women from antenatal clinics reported low condom use with their husbands, with no change throughout the period of the study. CONCLUSIONS: HIV risk behavioral surveillance is a useful way of determining whether behavior change has occurred in specific population groups. The results here confirm and add to a growing set of evidence of risk behavior reduction in Thailand. The behavioral changes did not occur uniformly but varied depending on the sexual dyad and the population group under study. Behavioral surveillance should be promoted and its methodologies strengthened in attempts to understand the local dynamics of HIV epidemics.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Rising HIV infection rates in Ho Chi Minh City herald emerging AIDS epidemic in Vietnam.

OBJECTIVE: To describe the epidemiology of HIV in Ho Chi Minh City in the context of current surveillance data from Vietnam. METHODS: Since the late 1980s, HIV surveillance data have been collected in Ho Chi Minh City from centers for the treatment of venereal disease and tuberculosis, centers for the rehabilitation of injecting drug users and sex workers, prenatal clinics, blood banks and other sites. RESULTS: The first case of HIV infection in Vietnam was identified in 1990 in Ho Chi Minh City. The cumulative number of reported HIV infections in this city at the end of 1996 was 2774, about half of the number of cases in the country; 86% of infections were among men, 86% among injecting drug users, 2.5% among patients with sexually transmitted diseases and 2.5% among sex workers. The first HIV infection among antenatal women was detected in 1994. The prevalence of HIV among injecting drug users rose dramatically from 1% in 1992 to 39% in 1996, compared with 1.2% among sex workers, 0.3% among blood donors and 1.3% among tuberculosis patients in 1996. The populations of injecting drug users and sex workers in Ho Chi Minh City are estimated to be 30000 and 80000, respectively, and rates of sexually transmitted diseases are 2-3 per 1000 persons per year. By the end of December 1996, 42 out of 53 provinces had reported HIV infections, and border areas near China and Cambodia began identifying large numbers of HIV-seropositive people. CONCLUSIONS: Ho Chi Minh City is at the forefront of a new HIV epidemic in Vietnam. This epidemic shows similarities to that in Thailand nearly a decade ago, with rapidly rising HIV rates among injecting drug users and infection already established among sex workers. Prevention efforts should include the targeting of injecting drug users and sex workers outside rehabilitation centers, the availability of sterile needles and condoms, the establishment of anonymous testing sites, the control of sexually transmitted diseases and the coordination of programs within southeast Asia.

Acquired Immunodeficiency Syndrome↗
PubMed1997

HIV/AIDS-related attitudes and practices of hospital-based health workers in Kampala, Uganda.

OBJECTIVE: To assess HIV/AIDS-related attitudes and practices of hospital-based health workers in Kampala, Uganda. METHODS: A cross-sectional study was conducted in Mulago Hospital, the main national referral hospital in Uganda. A total of 155 physicians and nurses completed a brief questionnaire on HIV risk perception, attitudes and practices regarding AIDS prevention education, HIV counseling and testing and care of patients with HIV disease. RESULTS: Twenty-nine per cent of health workers reported never having discussed AIDS prevention with patients, 26% had never referred patients for HIV counseling and 31% had never advised patients suspected of HIV infection to be tested. Frequent explanations for not providing AIDS prevention education included time constraints and/or lack of related knowledge or skills. While 29% perceived recapping needles as involving no risk, activities involving casual contact with patients and condom use for protection against HIV infection were associated with a high perceived risk of HIV transmission, particularly among nurses. Physicians and nurses differed in their HIV/AIDS-related attitudes and practices. The physicians had a more positive attitude towards the care of patients with HIV disease. In addition, 80% of physicians compared to 59% of nurses referred patients for HIV counseling. A similar trend was found for advising patients to obtain HIV testing. CONCLUSIONS: Hospital-based health workers are missing important opportunities for AIDS prevention education with their patients. There are gaps in their knowledge about HIV and related infection control practices. Interventions should address their concerns and barriers to HIV prevention practices.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Men with sexually transmitted diseases in Bangkok: where do they go for treatment and why?

OBJECTIVES: To describe and identify predictors of health-care seeking behavior among men with sexually transmitted diseases (STDs) in Bangkok, Thailand. DESIGN: Cross-sectional survey. METHODS: Men presenting with STDs were recruited from government clinics (n = 101), private clinics (n = 50) and pharmacies (n = 62). They completed interviewer-administered questionnaires on risk behavior, patterns of treatment-seeking for current and past STDs and attitudes toward health care. RESULTS: Two-thirds of all subjects had had a previous STD. Approximately one-half believed a partner other than a sex worker was the source of their current infection. Of the sample, 39% of men seen initially at drugstores, 29% at private clinics and 19% at government clinics sought subsequent treatment; failure to respond to therapy was the primary reason for seeking additional care. Men attending drugstores were likely to be younger, have less education and income, and to practice riskier sexual behavior. Patients at drugstores and general private clinics received the least amount of counseling or STD testing, while those attending specialized private STD clinics received the most comprehensive services. Attitudes towards government clinics were uniformly positive regardless of the site of enrollment; conversely, about 50% of clients at drugstores felt that the advice and treatment they received were inadequate. Convenience, affordability and lack of embarrassment were associated with choice of treatment site. CONCLUSIONS: STD/HIV control in Thailand must focus on improved treatment and counseling at the point of first encounter in the health-care system, particularly in the private sector. Men may be dissuaded from attending government clinics because of lack of convenience. Syndromic case management, incorporation of STD care at other public clinics and the recognition that more men practice unsafe sex with partners other than sex workers could improve STD control.

Adolescent↗
PubMed1997

Dietary iron and recurrence of colorectal adenomas.

Previous research suggests that iron acts as a prooxidant to increase the risk of colorectal neoplasia. This study examined effects of dietary intake of iron on colorectal adenoma recurrence using data from an antioxidant clinical trial. All subjects were free of polyps at study entry but had at least one adenoma removed within the 3 months before enrollment. Follow-up colonoscopies were conducted after 1 and 4 years. Patients who developed one or more adenomatous polyps between years 1 and 4 were classified as cases; all others were controls. Dietary iron intake at baseline and at the end of the study was estimated from self-administered food frequency questionnaires and averaged together for each subject, energy-adjusted, and categorized into quartiles. Odds ratios were adjusted for age, center, sex, calories, treatment group, and alcohol, fiber, folate, and fat intakes in unconditional logistic regression analysis. Dietary iron was inversely associated with adenoma risk, although risk did not decrease monotonically with increasing intake. Odds ratios comparing second, third, and fourth quartiles to the lowest quartile were 0.61 [95% confidence interval (CI), 0.37-1.02], 0.80 (95% CI, 0.45-1.44), and 0.37 (95% CI, 0.19-0.73), respectively. A limited examination showed no clear evidence that use of iron supplements affected risk of recurrence in this study population. This study provides evidence against the hypothesis that recent dietary intake of iron increases risk for colorectal adenomas. However, these results may reflect the presence of other dietary factors found in combination with iron.

Adenoma↗
PubMed1996

International renal-cell-cancer study. VI. the role of medical and family history.

A number of medical conditions have been linked with renal-cell cancer, although the evidence is not consistent in every case. In a large international case-control study of renal-cell cancer, we examined, among other hypotheses, associations with a personal history of certain medical conditions and a family history of cancer of the kidney or thyroid. Relative risks (RR), adjusted for the effects of age, gender, body-mass index, tobacco smoking and study centre, were significantly increased by a history of kidney stones or thyroid or kidney disease. The RR were not altered by additional adjustment for hypertension, or when diagnoses were restricted to those made at least 5 or 10 years before 1987 (the usual "cut-off" date). The link with kidney injury is particularly likely to be affected by recall bias. Increased RR of borderline significance were found for kidney infection (RR, 1.2) and diabetes (RR, 1.4). Having one first-degree relative with kidney cancer was associated with a significantly increased risk of renal-cell cancer (RR, 1.6; 95% Cl, 1.1-2.4). Seven cases reported 2 first-degree relatives with kidney cancer. No controls had first-degree relatives with kidney cancer. None of our participants reported having von Hippel-Lindau disease. The data suggests that a few conditions of the kidney are strongly associated with renal-cell cancer and that heredity plays a role in a small proportion of cases.

Adult↗