Biomedical subjects

J R Daling

Publications and source records attributed to J R Daling.

At least 163 records · Page 9Linked to original sources

PubMed1991

Maternal smoking, low birth weight, and ethnicity in relation to sudden infant death syndrome.

To determine independent effects of maternal smoking and infant low birth weight (less than 2,500 g) on risk of sudden infant death syndrome (SIDS) among different ethnic groups, the authors conducted a population-based case-control study based on the 1984-1989 Washington State birth record data. Two control groups were selected for 916 SIDS cases. The first one comprised 3,704 randomly selected controls, matched to cases by birth year, to describe the characteristics of the study population. In the second control group (n = 6,186), minorities were oversampled, by matching to cases on maternal race/ethnicity and birth year, to increase the power of analysis within each ethnic group. All subjects were classified into five groups on the basis of maternal race/ethnicity: white, black, American Indian, Asian, and Hispanic. After controlling for confounders, the authors found that maternal smoking was independently associated with SIDS among white (odds ratio (OR) = 2.2, 95% confidence interval (CI) 1.8-2.6), blacks (OR = 3.1, 95% CI 1.7-5.9), Asians (OR = 2.7, 95% CI 1.1-6.6, and Hispanics (OR = 5.5, 95% CI 1.4-22.0), but had little relation among American Indians (OR = 1.4, 95% Cl 0.9-2.4). Infant low birth weight was independently related to SIDS among whites (OR = 2.5, 95% Cl 1.8-3.4) and American Indians (OR = 5.5, 95% Cl 2.8-11.2) and to a lesser extent among blacks (OR = 1.9, 95% Cl 0.8-4.1), but not among Asians (OR = 1.1, 95% Cl 0.2-5.2) or Hispanics (OR = 1.2, 95% Cl 0.1-11.5). The misclassification that may occur because of the application of the same definition of low birth weight to all ethnic groups may be the main reason for the weaker association between infant low birth weight and SIDS among blacks and the absence of an association among Asians and Hispanics. Defining low birth weight as below population mean minus 1.96 standard deviations may provide better insight into the relation between low birth weight and SIDS. Understanding the reasons for the lack of a strong association between maternal smoking during pregnancy and SIDS among American Indians may enhance our knowledge of the etiology and pathogenesis of SIDS.

Adult↗

PubMed1991

Incidence of histologic types of uterine sarcoma in relation to menstrual and reproductive history.

To determine whether the occurrence of one or more histologic types of uterine sarcoma is related to events in a woman's reproductive life, a population-based case-control study was conducted. One-hundred sixty-seven women newly diagnosed with uterine sarcoma among residents of 6 geographic regions were compared to 208 women selected at random from the same populations with regard to histories of menstruation, pregnancy and childbearing, and breast feeding, as reported during a telephone interview. Compared to women whose menstrual periods began at age 13, women whose menses began earlier were at increased risk of leiomyosarcoma (OR = 2.0, 95% CI 0.9, 4.3); other histologic types were less strongly associated with early age at menarche. Women with leiomyosarcoma and endometrial stromal sarcoma, but not malignant mixed Müllerian tumors, tended to have ceased menstruating 2-3 years later than controls. None of the histologic types was clearly related to parity or to age at first live birth, but each was inversely related to age at last live birth. Associations were observed between leiomyosarcoma and histories of an induced abortion (OR = 4.2, 95% CI 1.2, 14.2) and of breast feeding after a live birth (OR = 0.5, 95% CI 0.3, 1.0); these relationships were not observed for other morphologic variants. These results suggest possible similarities and differences in menstrual and reproductive risk factors among histologic types of uterine sarcoma, and between these malignancies and the more common breast, endometrial and ovarian carcinomas.

Adult↗

PubMed1991

Progestagen supplementation of exogenous oestrogens and risk of endometrial cancer.

The favourable effects of exogenous progestagen on the endometrium are well known, but have not been adequately quantified with respect to endometrial cancer. The benefits of progestagen need to be weighted against its possible untoward effects on the risk of breast cancer and cardiovascular disease. A population-based case-control study of endometrial cancer was undertaken to evaluate the benefits of progestagen use. 158 incident cases were identified between 1985 and 1987 among women aged 40-64 years who were residents of King County, Washington. Detailed interviews were conducted and the responses were compared with those of 182 controls selected by random telephone digit dialling. The risk of endometrial cancer among women who had used unopposed oestrogen for more than 3 years was over five times that of women who had used no hormones (relative risk [RR] 5.7, 95% confidence interval [Cl] 2.5-12.8), whereas those who had also used a progestagen for at least six months of that time had an RR of only 1.6 (95% Cl 0.6-3.9). The RR differed according to days per month that progestagen was used: 2.4 (0.6-9.3) for progestagen use of less than 10 days per month versus 1.1 (0.4-3.6) for use of 10 or more days per month. These results provide additional evidence that the use of progestagen for 10 or more days per cycle can reduce the excess risk of endometrial cancer associated with long-term postmenopausal oestrogen use.

Adult↗

PubMed1991

Tubal sterilization and subsequent ectopic pregnancy. A case-control study.

OBJECTIVE: To assess the relative risk of ectopic pregnancy associated with postpartum or interval tubal sterilization. DESIGN: Case-control study using a comparison group of women of reproductive age at risk of pregnancy. SETTING: Group Health Cooperative of Puget Sound, a health maintenance organization based in Seattle, Wash. organization based in Seattle, Wash. PARTICIPANTS: Cases were 249 enrollees diagnosed as having an ectopic pregnancy between October 1, 1981, and September 30, 1986. Controls were 835 randomly selected enrollees matched to cases on age and county of residence. MEASUREMENTS: Information on interval sterilization history was obtained from interviews, examination of medical records, automated hospitalization files and a previously validated algorithm. A logistic regression model was used to estimate relative risks (RRs) for sterilized women compared with women using other types of or no contraception at the reference date. RESULTS: Controlling for age, county, race, smoking, income, gravidity, and prior use of a Dalkon Shield intrauterine device, the risk of ectopic pregnancy in women who had undergone interval sterilization was 3.7 (95% confidence interval [CI], 1.7 to 8.0) times that of women currently using oral contraception and 2.8 (95% CI, 1.5 to 5.5) times that of women currently using barrier contraceptive methods. Use of interval sterilization was associated with a risk of ectopic pregnancy similar to that of women using intrauterine devices (RR, 0.8; 95% CI, 0.4 to 1.7) and a risk lower than that of women who were not using contraception (RR, 0.2; 95% CI, 0.1 to 0.3). The corresponding RRs associated with postpartum sterilization were lower: 1.2 (95% CI, 0.3 to 3.9), 0.9 (95% CI, 0.3 to 2.8), 0.3 (95% CI, 0.1 to 0.8), and 0.1 (95% CI, 0.0 to 0.2), respectively. CONCLUSION: Tubal sterilization provides some protection against extrauterine as well as intrauterine pregnancy. It is likely that postpartum sterilization can be a safe alternative to all types of temporary contraception in terms of risk of ectopic pregnancy, while some types of interval sterilization may lead to an increased risk, in comparison with use of oral contraceptives or barrier methods.

Adolescent↗

PubMed1991

Antigenic stimulation and the occurrence of chronic lymphocytic leukemia.

Data from a population-based case-control study of chronic lymphocytic leukemia were analyzed to assess the possible etiologic role of chronic antigenic stimulation. The study, conducted in four geographic areas of the United States (the metropolitan areas surrounding Seattle, Washington, Salt Lake City, Utah, Detroit, Michigan, and Atlanta, Georgia) sought to identify all incident cases (n = 430) among residents diagnosed between July 1, 1977 and December 31, 1981. The responses of these cases to questions about possible sources of antigenic stimulation were compared with the responses of controls selected from the populations of these areas. Little difference between cases and controls was present for a history of most forms of viral and bacterial infection and for a history of allergies or allergy treatment. However, a relation was observed with antecedent syphilis infection (odds ratio (OR) = 5.0, 95% confidence interval (Cl) 2.0-12.9). Associations of smaller magnitude were observed with a history of tuberculosis (OR = 1.9, 95% Cl 1.0-3.7) and of urinary tract infection (OR = 1.4, 95% Cl 1.1-1.9). Overall, however, the authors found little evidence of a relation between chronic antigenic stimulation and the occurrence of chronic lymphocytic leukemia. Nonetheless, because the measure of prior antigenic stimulation was restricted to that obtained through interviews and undoubtedly was an insensitive one, these negative results should not be interpreted as ruling out antigenic stimulation as a possible cause of some cases of chronic lymphocytic leukemia.

Aged↗

PubMed1991

Maternal cigarette smoking and the risk of tubal pregnancy.

The association between maternal smoking and the occurrence of tubal pregnancy was evaluated in a population-based case-control study of members of the Group Health Cooperative of Puget Sound, Seattle, Washington. Women hospitalized with tubal pregnancy from October 1981 through September 1986 (n = 274) were compared with reproductive-age women who were at risk of becoming pregnant during the same time period (n = 727). The relative risk of tubal pregnancy associated with ever having smoked cigarettes was 1.3 (95% confidence interval (CI) 1.0-1.8). Compared with women who had never smoked, those who smoked at the time of conception had a 40% increase in the risk of tubal pregnancy (95% CI 1.0-2.0). These results support earlier epidemiologic and nonepidemiologic reports of a greater risk of tubal pregnancy associated with current or recent maternal cigarette smoking.

Case-Control Studies↗

PubMed1991

Occupation and the occurrence of testicular cancer.

To investigate what role a man's occupation may have on his risk of testicular cancer, we conducted a case-control study among noncryptorchid white males who were between 20 and 69 years of age and resided in western Washington State. Cases were men in whom a germ cell tumor of the testis was diagnosed between 1977 and 1984 (n = 323). Their occupational histories were compared to those of controls of the same age, race, and geographic area who were selected through random-digit dialing (n = 658). Administrators/managers (relative risk (RR) = 1.5), salesmen (RR = 1.5), electricians (RR = 2.8), and sailors and fishermen (RR = 3.1) were among the jobs reported more commonly by cases than controls. The risk among farmers/farm managers was also elevated (RR = 1.9), but not that among farm workers (RR = 0.6). No consistent association between any one occupation and testicular cancer has been observed across studies of this topic. The most frequent observation has been an over-representation among cases of certain types of white collar worker; this may reflect the influence of some other aspect of socioeconomic status and not occupational exposures per se.

Adult↗

PubMed1991

Rheumatoid arthritis in women. Incidence rates in group health cooperative, Seattle, Washington, 1987-1989.

As part of a prospective case-control study of newly diagnosed rheumatoid arthritis (RA) in women, we identified all cases of probable, definite, or classic RA diagnosed in 1987-1989 in 18-64-year-old women who were members of a health maintenance organization based in the Seattle, Washington area. Using both the 1958 and the 1987 American Rheumatism Association criteria for the diagnosis of RA and enrollment data from the health maintenance organization, we calculated the incidence by age and diagnostic class. Rates of RA incidence in women increased steadily with age. The incidence of probable, definite, or classic RA ranged from 13.1 per 100,000 person-years at risk for 18-29-year-old women to 82.1 per 100,000 person-years for 60-64-year-old women. The overall incidence rate, age-adjusted to the 1980 US female population, was 27.9/100,000 person-years. The overall incidence rate for definite/classic RA, age-adjusted to the 1980 US female population, was 23.9 per 100,000 person-years. When compared with adjusted rates of incidence of definite RA in Rochester, Minnesota, in 1950-1974, the incidence rates we found were 44.7% lower. Methodologic differences, changes in diagnostic criteria, and a declining incidence of RA among women over time may all be partial explanations for these results. The possible effects of reproductive factors, including oral contraceptives use, are discussed.

Adolescent↗

PubMed1991

Childhood brain tumor risk in relation to birth characteristics.

A population-based case-control study was conducted utilizing linked cancer registry and birth certificate data to examine potential associations between selected birth characteristics and the occurrence of brain tumors in children. Cases (n = 157) were those children ages 10 and under who were born in Washington state and who were diagnosed with a primary brain tumor between 1974 and 1986. Controls were randomly selected from the Washington State birth files and were matched 5:1 to cases on year and county of birth. A limited number of positive findings emerged from the study. Results suggested that high birthweight may be related to an increased risk of childhood brain tumor (odds ratio (OR) = 1.4, 95% CI 1.0-2.0 for all histologies combined; OR = 1.9, 95% CI 1.1-3.1 for astrocytomas). The risk of astrocytoma was also observed to be associated with older maternal age (OR = 2.2, 95% CI 1.2-4.0) and a history of prior fetal death(s) (OR = 1.9, 95% CI 1.0-3.8).

Birth Order↗

PubMed1991

Comparative virologic studies of condylomata acuminata reveal a lack of dual infections with human papillomaviruses.

Condylomata acuminata are epithelial proliferations caused by infection of the anogenital squamous epithelium with human papillomavirus (HPV). DNA-DNA hybridization techniques and the extremely sensitive polymerase chain reaction (PCR) were used to analyze biopsies from patients with clinically diagnosed condyloma acuminatum for the presence of HPV DNA. PCR analyses using primers and oligonucleotide probes specific for the E6/E7 region of HPV-6, -11, or -16 showed that 31 (93.9%) of 33 tissue biopsies contained HPV DNA: 22 contained type 6 DNA, 6 contained type 11 DNA, and 3 contained type 16 DNA. Eleven biopsies positive by PCR were Southern hybridization-negative or were considered inadequate for Southern analysis. In all 11, the presence of HPV DNA was corroborated by the observation of histopathologic evidence suggestive of HPV infection or by in situ hybridization. No evidence of multiple infections with HPV-6 or -11 and HPV-16 was seen.

Adult↗

PubMed1991

Vaginal douching and the risk of tubal pregnancy.

To explore the possible association between vaginal douching and tubal pregnancy, we interviewed 273 women who were diagnosed with tubal pregnancy at Group Health Cooperative between September 31, 1981 and October 1, 1986. Their responses were compared with responses of a random sample of 722 female members of Group Health Cooperative who were assumed to be at risk of becoming pregnant at the time the cases conceived. After adjusting for differences between cases and controls with regard to other measured risk factors, we found a modest increase in risk associated with having douched more than two times per year in the past (RR = 1.3, 95% CI: 0.9-1.8). Among women who had more than one sexual partner during their lifetime, however, the risk for those who had douched more than twice per year was somewhat higher (RR = 1.6, 95% CI: 1.1-2.3). There was an indication that women who had been exposed to Chlamydia trachomatis, as indicated by elevated antibody titers, may further increase their risk for tubal pregnancy by douching (RR = 2.4, 95% CI: 0.8-7.3). The associations found in other studies between douching and pelvic inflammatory disease, and between pelvic inflammatory disease and subsequent tubal pregnancy, argue that a relation between douching and tubal pregnancy might be anticipated. Our results offer further support for this hypothesis.

Adolescent↗

PubMed1991

Maternal smoking and placenta previa.

We conducted a case-control study of the relation between smoking and placenta previa, using Washington State birth certificate data from 1984 through 1987. The study population was comprised of live, singleton births to women whose pregnancies were complicated by placenta previa (N = 598) and randomly selected controls (N = 2,422) from the same time period. We used logistic regression to estimate odds ratios (OR) and their 95% confidence intervals (CI). Maternal smoking approximately doubled the risk of placenta previa after adjustment for the confounding effect of maternal age (OR = 2.1, 95% CI: 1.7-2.5).

Adult↗

PubMed1991

Genital warts, other sexually transmitted diseases, and vulvar cancer.

To determine whether specific sexually transmitted diseases were associated with an increased risk of vulvar cancer, we conducted a case-control study among residents of three countries in western Washington. We identified, interviewed, and obtained blood samples from women with in situ (n = 180) and invasive (n = 53) vulvar cancer, 18-79 years of age, who were first diagnosed with these diseases during 1980-1988. We compared their responses with those of 466 women from the general population who were identified by means of random digit dialing. On average, women with vulvar cancer reported a greater number of prior sexual partners than did controls. The risk of vulvar cancer was elevated among women who reported a prior history of condyloma (for in situ cancer, RR = 15.8; for invasive disease, RR = 17.3) or gonorrhea (for in situ cancer, RR = 2.2; for invasive disease, RR = 5.0). Women who were seropositive to herpes simplex virus type 2 (HSV-2) were at higher risk for carcinoma in situ than were controls (RR = 2.0). A history of nonspecific vaginitis, trichomoniasis, syphilis, or seropositivity to cytomegalovirus was not related to case-control status. These results indicate that only a subset of sexually transmitted diseases, particularly human papillomavirus, may play a role in the development of vulvar cancers.

Adolescent↗

PubMed1991

Results and effect of refusal recontact in a case-control study of ectopic pregnancy.

In a population-based study of ectopic pregnancy, a card-back system of initial subject contact yielded a positive response from 85.1% of potential cases and 65.0% of potential controls. We subsequently recontacted by telephone potential controls who had declined to participate and offered them $10 compensation for participation. We recontacted 205 of the 330 control women who had refused to participate. Twenty-eight were found to be ineligible, and 75.7% of the remaining 177 agreed to participate on recontact. The additional 125 women were not recontacted, 9 because of firm initial refusals and 116 because the study ended before contact could be sought or made. Controls who initially declined to participate but subsequently agreed differed from those who initially agreed on a number of demographic and reproductive characteristics, and estimates of ectopic pregnancy risk associated with induced abortion and tubal sterilization changed slightly with the inclusion of initial nonparticipants. We conclude that use of a card-back system of subject contact yields a low level of positive response among reproductive-aged women and that many initial nonparticipants can be converted into participants by personal contact and the offer of compensation.

Adult↗

PubMed1990

Wilms' tumor and paternal occupation.

A case-control study was conducted to examine the relationship between Wilms' tumor and paternal occupational exposures. The case group consisted of 200 children diagnosed as having Wilms' tumor who were registered at selected National Wilms' Tumor Study institutions during the period June 1, 1984, to May 31, 1986. Disease-free controls were matched to each case using a random digit dialing procedure. The parents of cases and controls completed a self-administered questionnaire. There was no consistent pattern of increased risk for paternal occupational exposure to hydrocarbons or lead found in this study. However, certain paternal occupations were found to have an elevated odds ratio (OR) of Wilms' tumor, including vehicle mechanics, auto body repairmen, and welders. Offspring of fathers who were auto mechanics had a 4- to 7-fold increased risk of Wilms' tumor for all 3 time periods. The largest increased odds ratio for auto mechanics was in the preconception period [OR = 7.58; 95% confidence interval (CI) = 0.90-63.9]. Welders had a 4- to 8-fold increased odds ratio, with the strongest association during pregnancy (OR = 8.22; CI = 0.95-71.3). Although chance cannot be excluded as a possible explanation, association of Wilms' tumor with these occupations has been reported in previous studies. Further study is needed to provide data on the specific occupational exposures involved.

Boron↗

PubMed1990

Use of electric blankets and risk of testicular cancer.

Electric blankets are an important domestic source of electromagnetic fields (EMF) because of the relatively high intensity of emission, prolonged exposure, and intimate contact with the source. In a case-control study of testicular cancer in western Washington during 1981 to 1984, the relation between EMF exposure from electric blankets and the occurrence of testicular cancer was examined. The respective proportions of cases and controls who reported the use of an electric blanket were almost identical (age-adjusted rate ratio (RR) = 1.0, 95% confidence interval (CI) 0.7-1.4). Distributions of the duration of use were also very similar in cases and controls. Compared with controls, the frequency of use of an electric blanket was slightly lower in men with seminoma (RR = 0.7, 95% CI 0.5-1.2) and slightly higher among men with nonseminoma germ cell tumors (RR = 1.4, 95% CI 0.9-2.3). Overall, the results of this study suggest that increased exposure to EMF from electric blankets contributes little, if at all, to the risk of testicular cancer in adult white men.

Bedding and Linens↗

PubMed1990

Cigarette smoking and acute nonlymphocytic leukemia.

In a case-control study of acute nonlymphocytic leukemia in western Washington state, cigarette smokers experienced a twofold increased risk of acute nonlymphocytic leukemia compared with nonsmokers. Risk increased significantly with the number of pack-years smoked (p = 0.0008) and decreased with the number of years stopped smoking (p = 0.15). The increased risk in smokers appeared to be limited to those who inhaled into the chest. The authors suggest that further studies of this potential relation are warranted, especially since the prevalence of cigarette smoking is relatively high in our society.

Case-Control Studies↗

PubMed1990

Recreational drug use and the risk of primary infertility.

Recreational drug (marijuana, lysergic acid diethylamide or LSD, speed, cocaine, and "other") exposures of women with primary infertility were compared with those of a matched control group of women with proven fertility. Women who reported smoking marijuana had a slightly elevated risk for infertility due to an ovulatory abnormality (RR = 1.7, 95% CI = 1.0 to 3.0). The risk was greatest among women who had used marijuana within one year of trying to become pregnant (RR = 2.1, 95% CI = 1.1 to 4.0). No consistent frequency or duration of use effects could be demonstrated, and the risk was confined to low-frequency users. Risks associated with the use of other drugs were not elevated. The risk of infertility from a tubal abnormality associated with cocaine use was greatly increased (RR = 11.1, 95% CI = 1.7 to 70.8). Our results are consistent with animal studies suggesting that smoking marijuana may cause a transient disruption of ovulatory function. The possibility that cocaine exposure influences the development of tubal infertility needs further investigation.

Adult↗