Reduced plasma volume and changes in vasoactive hormones in underweight pregnant women

The objective of this case-control study is to identify factors associated with the prevalence of minimal or mild endometriosis among infertile women. Cases (N = 329) were women diagnosed by laparoscopy with minimal or mild endometriosis and without any other factors explaining their infertility. Controls (N = 262) were women in whom the infertility remained unexplained after a diagnostic laparoscopy. Selected characteristics were documented by means of a face-to-face interview before the laparoscopy. The prevalence of minimal or mild endometriosis was higher in women age 25 years or older, in those who reported menarche at the age of 13 years [prevalence odds ratio (POR) = 1.63; 95% confidence interval (CI) = 1.02-2.60] or older (POR = 1.73; 95% CI = 1.07-2.78), menstrual cycles of 27 days or less (POR = 1.63; 95% CI = 1.02-2.60), or caffeine intake of 300 mg per day or more (POR = 1.33; 95% CI = 0.91-1.94). The prevalence of minimal or mild endometriosis was inversely related to body mass index. Parous women were less likely to have endometriosis (POR = 0.61; 95% CI = 0.39-0.96) than were nulliparous women. Education, duration of infertility, and smoking status were not related to the presence of endometriosis.     

The association of calcium and vitamin D, and colon and rectal cancer in Wisconsin women

BACKGROUND: Calcium and vitamin D have been hypothesized to reduce colorectal cancer risk. Epidemiological evidence, however, is mixed. METHODS: To explore those relationships, data were collected as part of a population-based, case-control study of colorectal cancer in Wisconsin women (678 controls, 348 colon and 164 rectal cancer cases). A semi-quantitative food frequency questionnaire was used to ascertain food and dietary supplement intake 2 years prior to interview. Logistic regression models were used to calculate odds ratios (OR). RESULTS: Higher levels of calcium intake were associated with reduced colon and rectal cancer risk. The following adjusted OR and 95% confidence intervals (CI) were observed, comparing the fifth quintile (based on control intake) with the first: colon cancer: OR = 0.6, 95% CI: 0.4-1.0, P-trend: 0.03; rectal cancer: OR = 0.6, 95% CI: 0.3-1.1, P-trend: 0.07. Similar relationships were observed for vitamin D intake, although OR were closer to the null value and did not always behave in a step-wise fashion (fifth quintile versus the first--colon cancer: OR = 0.7, 95% CI: 0.4-1.1, P-trend: 0.05; rectal cancer: OR = 0.8, 95% CI: 0.5-1.5, P-trend: 0.42). CONCLUSION: These data support a protective association of calcium on colon and rectal cancer risk.     

Biologic activity of interleukin 1 (IL-1) alpha in patients with refractory malignancies

To examine the effects of smoking and N-acetylation genetics on breast cancer risk, we analyzed data from an ongoing, population-based, case-control study of invasive breast cancer in North Carolina. The study population consisted of 498 cases and 473 controls, with approximately equal numbers of African-American and white women, and women under the age of 50 and age 50 years or older. Among premenopausal women, there was no association between current smoking [odds ratio (OR), 0.9; 95% confidence interval (CI), 0.5-1.5] or past smoking (OR, 1.0; 95% CI, 0.6-1.6) and breast cancer risk. Among postmenopausal women, there was also no association with current smoking (OR, 1.2; 95% CI, 0.7-2.0); however, a small increase in risk was observed for past smoking (OR, 1.5; 95% CI, 1.0-2.4). For postmenopausal women who smoked in the past, ORs and 95% CIs were 3.4 (1.4-8.1) for smoking within the past 3 years, 3.0 (1.3-6.7) for smoking 4-9 years ago, and 0.6 (0.3-1.4) for smoking 10-19 years ago. Neither N-acetyltransferase 1 (NAT1) nor N-acetyltransferase 2 (NAT2) genotype alone was associated with increased breast cancer risk. There was little evidence for modification of smoking effects according to genotype, except among postmenopausal women. Among postmenopausal women, ORs for smoking within the past 3 years were greater for women with the NAT1*10 genotype (OR, 9.0; 95% CI, 1.9-41.8) than NAT1-non*10 (OR, 2.5; 95% CI, 0.9-7.2) and greater for NAT2-rapid genotype (OR, 7.4; 95% CI, 1.6-32.6) than NAT2-slow (OR, 2.8; 95% CI, 0.4-8.0). Future studies of NAT genotypes and breast cancer should investigate the effects of environmental tobacco smoke, diet, and other exposures.     

Treatment for infertility and risk of invasive epithelial ovarian cancer

The relationship between the use of fertility drugs and the risk of ovarian cancer was analysed using data from an Italian case-control study. The study comprised 971 women below the age of 75 years with histologically confirmed invasive epithelial ovarian cancer diagnosed within the year before the interview. The controls were 2758 women admitted to the same network of hospitals where the cases of ovarian cancer had been identified. Five cases (0.5%) and 11 controls (0.4%) reported use of fertility drugs. In comparison with women who had never used fertility drugs, the multivariate odds ratio (OR) for women who had taken fertility drugs was 1.1 [95% confidence interval (CI) 0.4-3.3]. The OR were 0.7 (95% CI 0.1-7.9) and 1.0 (95% CI 0.2-3.8) for women who had used fertility drugs for <6 and > or =6 cycles respectively. Considering the 14 cases and 45 controls reporting difficulty in conception, the risk of ovarian cancer was 0.5 (95% CI 0.1-3.6) for women who reported use of fertility drugs. Considering nulliparous women only, the estimated OR of ovarian cancer for any fertility drug use was 0.6 (95% CI 0.1-3.5). Although the present results have limitations in terms of statistical power and available information, they provide reassuring evidence of the absence of a strong association between fertility drugs and subsequent risk of developing epithelial ovarian cancer.     

Genetic polymorphisms in catechol-O-methyltransferase, menopausal status, and breast cancer risk

Polymorphic catechol-O-methyltransferase (COMT) catalyzes the O-methylation of estrogen catechols. In a case-control study, we evaluated the association of the low-activity allele (COMT(Met)) with breast cancer risk. Compared to women with COMT(Val/Val), COMT(Met/Met) was associated with an increased risk among premenopausal women [odds ratio (OR), 2.1; confidence interval (CI), 1.4-4.3] but was inversely associated with postmenopausal risk (OR, 0.4; CI, 0.2-0.7). The association of risk with at least one low-activity COMT(Met) allele was strongest among the heaviest premenopausal women (OR, 5.7; CI, 1.1-30.1) and among the leanest postmenopausal women (OR, 0.3; CI, 0.1-0.7), suggesting that COMT, mediated by body mass index, may be playing differential roles in human breast carcinogenesis, dependent upon menopausal status.     

Managed obstetrical care

BACKGROUND: Infertility is common in Africa, but virtually no data exist on HIV prevalence among infertile women. Mainly anthropological studies in Africa have shown that infertile women have higher risks of marital instability and possibly also have more sexual partners than fertile women. METHOD: This study was conducted in a hospital in northwest Tanzania during 1994 and 1995. Women presenting themselves with infertility problems to the outpatient clinic were interviewed, examined and blood was drawn. Women who came to deliver in the hospital, excluding primiparae, were taken as a control group. The analysis was limited to women > or = 24 years. In total 154 infertile and 259 fertile women were included in the study. RESULTS: HIV prevalence was markedly higher among infertile women than among fertile women: 18.2% and 6.6% respectively (adjusted odds ratio [OR] for age, residence and occupation 2.7; 95%-confidence interval [CI]: 1.4-5.3). Data on past sexual behaviour showed that infertile women had more marital breakdowns, more lifetime sexual partners and a higher level of exposure to sexually transmitted diseases (STD). CONCLUSION: Women with fertility problems appear to have higher HIV prevalence, which justifies more attention for such women in the context of AIDS programmes. In addition, caution is needed when using sentinel surveillance data from antenatal clinics to monitor HIV prevalence.     

Beta 2-microglobulin as a predictor of death in HIV-infected women from Kigali, Rwanda

OBJECTIVE: To determine if beta 2-microglobulin (beta 2M) predicts death among HIV-infected African women. DESIGN: Nested case-control study. SETTING: Kigali, Rwanda. PARTICIPANTS: Two hundred and five seroprevalent women known to be HIV-infected since 1986-1987; 67 of whom died of HIV disease (cases) and 138 were alive (controls) as of November 1991. In addition, 128 women who seroconverted between 1986 and 1991. MAIN OUTCOME MEASURES: HIV serology, clinical signs and symptoms of HIV disease, hematology variables, and beta 2M concentration. RESULTS: beta 2M concentration increased over time (P < 0.001) in the seroprevalent women and seroconvertors. The average rate of beta 2M increase in women who died was 0.5 compared with 0.3 mg/l/year in the vital, seroprevalent women (P = 0.07). The strongest independent predictors of death were the rate of change of beta 2M (mg/l/year) [odds ratio (OR), 3.4; 95% confidence interval (CI), 1.7-6.8] and baseline beta 2M concentration (mg/l) [OR, 1.6; 95% CI, 1.2-2.1]. The rate of death for women with beta 2M concentration > or = 7.0 mg/l and a rate of change of beta 2M > or = 0.4 mg/l/year was 7.3 times higher than for women with beta 2M concentration < 7.0 mg/l and a rate of change of beta 2M of < 0.4 mg/l/year (95% CI, 3.1-17.2). The estimated median time from seroconversion to death assuming a constant rate of change of beta 2M was 10.6 years (95% CI, 9.9-11.2) for this cohort of HIV-infected women. CONCLUSIONS: Elevated beta 2M and a high rate of beta 2M increase were strongly associated with mortality among HIV-infected African women. Based on survival estimates using the rate of change of beta 2M, HIV-infected African women have similar survival compared with HIV-infected adults in the United States.     

Erythrocyte glutathione balance and membrane stability during preeclampsia

OBJECTIVE: To assess the risk of borderline ovarian cancer among infertile women treated with fertility drugs. DESIGN: Case-control study. SETTING: Nationwide data obtained from public registers and postal questionnaires. PATIENT(S): All Danish women <60 years old with borderline ovarian cancer during the period 1989-1994 and randomly selected population controls. The analysis included 231 cases and 1,721 controls. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Influence of parity, infertility, and fertility drugs on the risk of borderline ovarian cancer after multivariate confounder control. RESULT(S): The odds ratio (OR) for borderline ovarian cancer among infertile untreated nulliparous women compared with fertile nulliparous women was 1.9. The OR for borderline ovarian cancer among treated nulliparous women compared with untreated infertile nulliparous women was 1.5, and the OR among treated parous women compared with untreated infertile parous women was 1.5. CONCLUSION(S): Among fertile women, the difference in the risk of borderline ovarian cancer between nulliparous women and parous women was not statistically significant. Nulliparous women who were infertile and who did not receive medical treatment had a twofold higher risk of borderline ovarian cancer than fertile nulliparous women. There was no statistically significant increase in the risk of borderline ovarian cancer among nulliparous women who were treated with fertility drugs compared with nulliparous untreated infertile women or among parous women who were treated with fertility drugs compared with parous untreated infertile women.     

Breast cancer among women exposed to polybrominated biphenyls

We conducted a nested case-control study with 1,925 women enrolled in a polybrominated biphenyl (PBB) registry to examine the association between breast cancer and serum PBBs. Twenty women who developed breast cancer were matched to 290 control subjects on sex, race, and age. Women with serum PBB levels of 2.0-3.0 parts per billion (ppb) [odds ratio (OR) = 3.5; 95% confidence interval (CI) = 0.9-13] or 4.0 ppb or greater (OR = 3.1; 95% CI = 0.8-12) had a higher estimated risk for breast cancer than women with less than 2.0 ppb. The odds ratios were unchanged when available breast cancer risk factors were included in the analysis.     

Sexual risk behavior and risk factors for HIV-1 seroconversion in homosexual men participating in the Tricontinental Seroconverter Study, 1982-1994

Trends in sexual behavior associated with incident infection with human immunodeficiency virus (HIV) type 1 are described and a case-control study was conducted to examine risk factors for HIV seroconversion in homosexual men who became infected with HIV between 1982 and 1994 from four geographic sites: Amsterdam, the Netherlands; San Francisco, California; Vancouver, Canada; and Sydney, Australia. Changes in sexual behaviors were evaluated from cohort visits in the preseroconversion, seroconversion, and postseroconversion intervals and were further examined over three time periods: 1982-1984, 1985-1987, and 1988-1994. In a case-control study, sexual behaviors, substance use, and presence of sexually transmitted disease were compared between 345 HIV-positive cases and 345 seronegative controls matched by visit date and site. Receptive anal intercourse was the sexual behavior most highly associated with seroconversion. The odds ratio (OR) per receptive anal intercourse partner increase was 1.05 (95% confidence interval (CI) 1.02-1.09). To more carefully examine risk associated with receptive oral intercourse, analyses were done in a subgroup of men who reported no or one receptive anal intercourse partner. The risk (OR) associated with receptive oral intercourse partner increase was 1.05 (95% CI 1.0-1.11). In multivariate conditional logistic regression analyses, presence of sexually transmitted disease (OR = 3.39, 95% CI 1.95-5.91) and amphetamine use (OR = 2.55, 95% CI 1.26-5.15) were independently associated with seroconversion. Although the prevalence of major risk factors has decreased over time, the associations of these behaviors and HIV infection persist, suggesting that these risk behaviors remain important avenues for public health interventions.     

Evaluation of an immunoturbidimetric assay for haemoglobin A1c on a Cobas Mira S analyser

A case-control study was carried out in Spain to assess associations between parity, lactation and age at first full-term pregnancy and breast cancer. From November 1989 to February 1992, 184 incident breast cancer histologically confirmed cases were interviewed and matched by age and residence to 184 hospitalized patients and 184 community controls selected by random digit dialing. Multiple logistic regression was used to assess the independent influence of each factor on the risk of breast cancer in relation to other factors included in the model. Age at first full-term pregnancy was associated with breast cancer risk with an estimated odds ratio of 3.5 (95% CI 1.41-9.83) for women with their first birth after 30 years in comparison with those whose first birth was before age 21. Breast cancer risk decreased with increasing number of full-term pregnancies, OR 0.3 (95% CI 0.16-0.78) for women who had had more than 3 full-term pregnancies in comparison with nulliparous women. Among parous women, the estimated OR for women with more than 3 children was 0.4 (95% CI 0.13-0.81) after allowance for age at first childbirth and lactation. The estimated OR was 2.6 (95% CI 1.4-4.7) for women with a positive history of breast cancer in first-degree relatives. Breast cancer was not associated with total duration of lactation. The study indicates that parity is an independent risk factor associated to breast cancer and that the women with a late age at first full-term pregnancy constitute a high-risk group.     

Risk factors for incident radiographic knee osteoarthritis in the elderly: the Framingham Study

OBJECTIVE: Knee osteoarthritis (OA) is highly prevalent, especially in the elderly. Preventive strategies require a knowledge of risk factors that precede disease onset. The present study was conducted to determine the longitudinal risk factors for knee OA in an elderly population. METHODS: A longitudinal study of knee OA involving members of the Framingham Study cohort was performed. Weight-bearing knee radiographs were obtained in 1983-1985 (baseline) and again in 1992-1993. Incident disease was defined as the occurrence of new radiographic OA (Kellgren and Lawrence grade > or = 2 on a 0-4 scale) in those without radiographic OA at baseline. Risk factors assessed at baseline and in the interim were tested in univariate and multivariate equations to evaluate their association with incident knee OA. RESULTS: Of 598 patients without knee OA at baseline (mean age 70.5 years, 63.7% women), 93 (15.6%) developed OA. After adjustment for multiple risk factors, women had a higher risk of OA than did men (adjusted odds ratio [OR] = 1.8, 95% confidence interval [95% CI] 1.1-3.1). Higher baseline body mass index increased the risk of OA (OR = 1.6 per 5-unit increase, 95% CI 1.2-2.2), and weight change was directly correlated with the risk of OA (OR = 1.4 per 10-lb change in weight, 95% CI 1.1-1.8). Physical activity increased the risk of OA (for those in the highest quartile, OR = 3.3, 95% CI 1.4-7.5). Smokers had a lower risk than did nonsmokers (for those who smoked an average of > or = 10 cigarettes/day, OR = 0.4, 95% CI 0.2-0.8). Factors not associated with the risk of OA included chondrocalcinosis and a history of hand OA. Weight-related factors affected the risk of OA only in women. CONCLUSION: Elderly persons at high risk of developing radiographic knee OA included obese persons, nonsmokers, and those who were physically active. The direction of weight change correlated directly with the risk of developing OA.     

Hormone replacement therapy as a risk factor for epithelial ovarian cancer: results of a case-control study

OBJECTIVE: To evaluate the role of hormone replacement therapy (HRT) as a risk factor for the development of epithelial ovarian cancer. METHODS: A case-control study was performed that used 491 patients with epithelial ovarian cancer frequency matched for age at diagnosis (+/-5 years) with a control population of 741 patients with malignancies of nonestrogen-dependent tissues. The odds ratio (OR) for the development of epithelial ovarian cancer was estimated using logistic regression analysis with adjustment for age at diagnosis, parity, oral contraceptive use, smoking history, family history of epithelial ovarian cancer, age at menarche, menopausal status, income, and education. RESULTS: One hundred of 491 patients (20.4%) in the study population had ever used HRT, and 160 of 741 patients (21.6%) in the control population had ever used HRT (OR 0.85; 95% confidence interval [CI] 0.62, 1.2). A significant association between HRT and specific histologic subtypes of epithelial ovarian cancer was not demonstrable for serous cystadenocarcinoma (OR 1.2, 95% CI 0.8, 1.7), Clear cell carcinoma (OR 1.1, 95% CI 0.4, 3.4), or endometrioid carcinoma (OR 0.4; 95% CI 0.2, 1.2). A significant association between duration of use of HRT and the risk of developing epithelial ovarian cancer was not demonstrable for under 5 years (OR 0.8; 95% CI 0.5, 1.2), 5-9 years (OR 0.6; 95% CI 0.3, 1.1), or 10 or more years (OR 0.6; 95% CI 0.3, 1.4). CONCLUSION: A significant association between the use of HRT and the risk of developing epithelial ovarian cancer, even with prolonged exposure, is not demonstrable.     

Cellular glutathione peroxidase is the mediator of body selenium to protect against paraquat lethality in transgenic mice

A case-control study was conducted between 1992 and 1996 in six Italian areas. It included 537 women with colon cancer, 291 women with rectal cancer and 2081 control women in hospital for acute conditions, unrelated to hormonal or gynaecological diseases. A higher age at menopause was associated with increased colon cancer risk (odds ratio (OR) for > or = 53 years compared with < 50 years = 1.39, 95% confidence interval (CI) 1.04-1.87). Among parous women, a significant trend of decreasing colon cancer risk with increasing number of births was seen for colon (OR for > or = 4 births compared with 1 birth = 0.62, 95% CI 0.42-0.90), but not for rectal cancer. Nulliparous women, however, were at lower risk than women with a single birth, and age at first birth was directly associated with risk. While oral contraceptive use showed no significant influence, ever users of hormone replacement therapy had a reduced risk of rectal cancer (OR = 0.56, 95% CI 0.31-1.01). Thus, the association of colorectal cancer with reproductive and menstrual factors is neither strong nor consistent.     

Intramural aortic dissection

OBJECTIVE: To investigate possible associations between tobacco smoking and alcohol consumption and the risk of adult glioma. DESIGN: This was a population based, case-control study. Relative risks (RR) were estimated using logistic regression analysis. SETTING: Melbourne, Australia. PARTICIPANTS: These comprised 416 case subjects (166 women, 250 men), 66% of those eligible; and 422 control subjects (170 women, 252 men), 43.5% of those potentially eligible. RESULTS: There was no increase in risk of glioma with having ever smoked tobacco (RR 1.29, 95% CI 0.95, 1.75) for all subjects, adjusted for age, a reference date, and gender. There was a slight increase in risk for men (RR 1.64, 95% CI 1.1, 2.45), but not for women (RR 0.99, 95% CI 0.62, 1.62). For men, there was no increase in risk with increasing pack-years of cigarette smoking, but the risk was significantly increased in subjects who had smoked for less than 10 years. There was no increase in risk associated with having ever drunk alcohol for all subjects (RR 0.96, 95% CI 0.67, 1.37), women (RR 0.69, 95% CI 0.4, 1.15) or men (RR 1.40, 95% CI 0.81, 2.43). CONCLUSIONS: This study does not support an association between either tobacco smoking or alcohol consumption and glioma. The pattern of risk associated with tobacco smoking in men appears inconsistent with a causal role, and may be due to chance, response bias, or uncontrolled confounding.     

Na+,K(+)-ATPase activity is selectively increased in thalamus in thiamine deficiency prior to the appearance of neurological symptoms

OBJECTIVES: We analyzed the relationship between menstrual and reproductive history and risk of hip fractures in post-menopausal women using data from an Italian case-control study. METHODS: Cases were 206 post-menopausal women admitted for fractures of the hip proximal femur to a network of teaching and general hospitals in Milan, Italy. The comparison group consisted of 590 post-menopausal women admitted to the same network of hospitals for acute, non-neoplastic, non-hormone-related conditions, other than traumatic or orthopedic disorders. Odds ratios (OR) of hip fracture were derived from unconditional multiple logistic regression. RESULTS: No relation emerged between risk of hip fractures and age at menarche, lifelong menstrual cycle pattern and age at menopause. In comparison with women with age at menopause > or = 53 years, the multivariate OR of hip fractures were 1.2, 1.1, 1.2 and 0.5 in women with menopause at 50-52, 45-49, 40-44 and before 40 years (X2(1) trend 0.21). In comparison with nulliparae, the estimated age-adjusted OR was 0.6 (95% confidence interval, CI, 0.4-0.9) for parous women, but the multivariate estimate was not significant (OR 0.8, 95% CI 0.6-1.3) and the multivariate trend in risk with number of births was not significant either. No relation emerged between hip fractures and age at first and last birth, and history of abortions. CONCLUSIONS: This study found no relevant influence of menstrual and reproductive factors on the risk of hip fractures in post-menopausal women. However, this is not in contrast with the observation of a short-term effect of menopause and more in general. female hormone levels on osteoporosis and hence on hip fractures.     

Evaluation of status of tuberculin skin sensitivity test among medical students

BACKGROUND: The role of lipoproteins as markers of peripheral arterial disease (PAD) is not well defined. METHODS: We measured both lipid and non-lipid risk factors in 51 male patients with angiographically proven PAD and in 56 control subjects. The independent association of risk factors with PAD was evaluated by means of a multiple logistic regression analysis. RESULTS: The levels of cholesterol bound to high density lipoprotein (HDLc) and to its subfraction HDL2 were lower and triglycerides were higher in patients than in control subjects (1.0 +/- 0.3 vs 1.2 +/- 0.3, p < 0.003; 0.4 +/- 0.2 vs 0.5 +/- 0.3, p < 0.03; and 1.8 +/- 1.2 vs 1.3 +/- 0.7, p < 0.02, respectively). Total cholesterol and LDLc levels were similar in both groups. In the multiple logistic regression analysis that was done with lipid parameters, a statistically significant association of triglycerides (OR = 1.73; CI95% = 1.06-2.80) and HDLc (OR = 0.15; CI95% = 0.05-0.50) with PAD was observed, while HDL subfractions and apolipoproteins were not significantly associated. In the multiple logistic regression analysis that was done with non-lipid parameters, hypertension (OR = 5.35; CI95% = 1.86-15.4) and smoking (packs-year) (OR = 1.04; CI95% = 1.10-1.06) were the only significantly associated with PAD. When lipid and non-lipid parameters were included in the regression analysis, a statistically significant association between hypertension, smoking and HDLc with PAD was observed. CONCLUSIONS: Among lipid risk factors, a low HDLc and high triglycerides, and among non-lipid risk factors hypertension and smoking, are significantly and independently associated with lower limb arteriopathy.     

Risk factors for lung cancer in young adults

Risk factors for early onset of lung cancer are relatively unknown. In a case-control study, carried out in Germany between 1990 and 1996, the effects of smoking and familial aggregation of cancer were compared in 251 young cases and 280 young controls (< or = 45 years) and in 2,009 older cases and 2,039 older controls (55-69 years). The male/female ratio was 2.6/1 in young patients and 5.6/1 in older patients. Adenocarcinomas were more frequent in young men than in older men (41 % vs. 28%). Duration of smoking and amount smoked showed significantly increased odds ratios for lung cancer in both age groups. Lung cancer in a first degree relative was associated with a 2.6-fold (95% confidence interval (CI) 1.1-6.0) increase in the risk of lung cancer in the young age group, but no elevated risk was seen in the older group (OR = 1.2, 95% CI 0.9-1.6). Smoking-related cancer in relatives with the age at diagnosis under 46 years was associated with an increased risk of lung cancer in the young group (OR = 5.6, 95% CI 0.7-46.9) but not in the older group (OR = 0.7, 95% CI 0.3-1.5). Results indicated that lung cancer risk in young and older age groups shows remarkable differences with respect to sex, histologic type, and genetic predisposition.     

Increased risk of placenta previa among women of Asian origin

OBJECTIVE: To investigate the frequency of placenta previa among Asian women. METHODS: We conducted a population-based case-control study using Washington state birth certificate data from 1984-1987. Our study population included 810 women with pregnancies complicated by placenta previa and 2917 randomly selected controls. Unconditional logistic regression was used to estimate odds ratios (OR) and their 95% confidence intervals (CI), and interaction terms were used to examine effect modification. Potential confounding by maternal age, gravidity and parity, maternal smoking during pregnancy, and a history of abortion or cesarean delivery was adjusted for in the analysis. RESULTS: The frequency of placenta previa during the study period was 3.3 per 1000 live births. Women of Asian origin were 86% more likely (OR 1.86, 95% CI 1.38-2.51) to have a delivery complicated by placenta previa than were white women. This association was stronger among women without a previous live birth (OR 2.51, 95% CI 1.57-4.01) than those who previously had experienced a live birth (OR 1.50, 95% CI 1.01-2.25). CONCLUSION: Asian women residing in the United States are at increased risk of placenta previa. If confirmed by others, our results suggest that obstetricians should consider meticulous ultrasound evaluations during pregnancy to rule out the presence of placenta previa in Asian-American women.     

Patterns of sexual and injecting risk behaviours in French intravenous drug users not reporting HIV and hepatitis C virus seropositivities

AIMS: To characterize and identify determinants of risk behaviour patterns of intravenous drug users (IDUs) independently of changes due to knowledge of HIV or hepatitis C Virus (HCV) seropositivity. DESIGN: A cross-sectional survey using a structured questionnaire concerning sexual, injecting and HIV and HCV antibody testing practices. SETTING: IDUs were interviewed in the Paris region at 10 treatment or psychosocial centres. PARTICIPANTS: Six hundred and twelve consecutive sexually active IDUs over 18 years able to answer the questionnaire. MEASUREMENTS: Five hundred and ninety-five IDUs completed the questionnaire. The risk-behaviour patterns of the 328 IDUs not reporting HIV or HCV seropositivity were analysed by phi correlation. Risk factors for each risk behaviour were determined by regression logistic models yielding odds ratios (OR) and their 95% confidence intervals (95% CI). FINDINGS: Several risk behaviour patterns were suggested: (1) lending, borrowing; (2) not or inconsistently testing HIV and HCV serology and not or inconsistently using condoms; (3) having multiple partners and prostitution; and (4) not using clean equipment. Alcohol abuse was independently and specifically associated with lending (OR = 3.8; 95% CI: 2.1-7.0) and borrowing (OR = 3.3; 95% CI: 1.8-6.1); homelessness with injecting risk behaviours and with prostitution (OR = 2.7; 95% CI: 1.2-6.1); low educational level and having children with not or inconsistently using condom and serology testing; and cocaine use with not or inconsistently using condoms (OR = 0.4; 95% CI: 0.3-0.7) and serology testing and not using clean equipment (OR = 0.4; 95% CI: 0.2-0.8). Having multiple partners and prostitution had no common risk factors. CONCLUSIONS: Identifying specific risk factors could help to target drug harm reduction programmes for each risk behaviour pattern among IDUs not reporting HIV and HCV seropositivity.