Weiss Ns

Use of antidepressant medications in relation to the incidence of breast cancer

Although associations have been reported between antidepressant use and risk of breast cancer, the findings have been inconsistent. We conducted a population-based case–control study among women enrolled in Group Health Cooperative (GHC), a health maintenance organization in Washington State. Women with a first primary breast cancer diagnosed between 1990 and 2001 were identified (N=2904) and five controls were selected for each case (N=14396). Information on antidepressant use was ascertained through the GHC pharmacy database and on breast cancer risk factors and screening mammograms from GHC records. Prior to one year before diagnosis of breast cancer, about 20% of cases and controls had used tricyclic antidepressants (adjusted odds ratio=1.06, 95% CI 0.94–1.19) and 6% of each group had used selective serotonin reuptake inhibitors (OR=0.98, 95% CI 0.80–1.18). There also were no differences between cases and controls with regard to the number of prescriptions filled or the timing of use. Taken as a whole, the results from this and other studies to date do not indicate an altered risk of breast cancer associated with the use of antidepressants overall, by class, or for individual antidepressants.

Current use of an intrauterine device and risk of tubal pregnancy.

Using data from a population-based, case-control study, we assessed risk of tubal pregnancy associated with use of an intrauterine device (IUD) at the time of conception. Cases were 249 members of Group Health Cooperative of Puget Sound who experienced a tubal pregnancy between 1981 and 1986. Controls were 831 members at risk of ectopic pregnancy who were similar to cases with respect to age and county of residence, but otherwise selected at random. Risk of tubal pregnancy associated with current IUD use was compared separately to that among users of various other (or no) contraceptive methods. Tubal pregnancy was more likely to occur among IUD users than among women using oral contraceptives [relative risk (RR) = 3.8, 95% confidence interval (CI) = 1.5–9.9] or barrier methods (RR = 3.6, 95% CI = 1.6–8.1), or, to a lesser extent, among women who had been surgically sterilized (RR = 1.6, 95% CI = 0.8–3.5). In contrast, IUD users were much less likely to experience a tubal pregnancy (RR = 0.2, 95% CI = 0.1–0.4) than were women who were currently not contracepting. For most women, the decision to use an IUD occurs within the context of choosing among various contraceptive methods. Our results indicate that, for these women, the decision to use an IUD results in increased risk of ectopic pregnancy while the device is in use.

Induced abortion and the risk of subsequent ectopic pregnancy

This study assessed the effect of legal induced abortion on ectopic pregnancy risk by using a comparison group of reproductive-age women who were at risk of becoming pregnant during the same time period the women with ectopic pregnancy conceived. Cases were members of Group Health Cooperative of Puget Sound who were hospitalized for ectopic pregnancy from October 1981 through September 1986 (N = 211). Controls were randomly selected members matched to cases on age and county of residence (N = 457). All subjects in this analysis had had one or more prior pregnancies. Eighty-eight cases (41.7 per cent) and 177 controls (38.7 per cent) had a history of one or more induced abortions. The relative risk of ectopic pregnancy associated with one abortion was 0.9 (95 per cent confidence interval 0.6, 1.3), adjusted for age, county, reference date, religion, gravidity, age at first pregnancy, lifetime number of sexual partners, and miscarriage history. Among women with two or more prior pregnancies, the risk associated with two or more abortions was 1.2 (0.6, 2.4). Controlling for pelvic inflammatory disease and use of intrauterine devices did not alter these risks. We conclude that legal abortion as performed in the US since 1970 has little or no influence on a womans risk of ectopic pregnancy in subsequent pregnancies.

The intrauterine device and primary tubal infertility [letter].

The results of a population-based retrospective case-control study published in 1985 on the link between prior use of an IUD and primary tubal infertility have been re-analyzed. The original results set the relative risk of tubal infertility at 2.6 for ever users of an IUD but 6.8 for users of the Dalkon shield. The new calculations eliminated cases of infertility due to abnormalities verified by hysterosalpingography such as bicornuate uterus or uterine polyps; included 15 cases for whom no matched controls with the same matching criteria. The new data set included 487 of 518 potential controls for 161 cases. The new computation yielded a relative risk of 3.7 for ever-use of any IUD 3.9 for ever-use of a copper IUD 6.0 for ever-use of a Dalkon shield and 3.4 for ever-use of any IUD except the Dalkon shield. These results did not change the original interpretation of the study: that while the risks of infertility is heightened after use of the Dalkon shield it is still higher after use of any IUD for nulligravid women.

The association of condylomata acuminata and squamous carcinoma of the vulva

Evidence from several sources suggests that the presence of vulvar condylomata acuminata predisposes to the development of carcinoma at that site [Buscema et al., 1980; Friedrich et al., 1980; Kovi et al., 1974; Rastkar et al., 1982; and Woodruff et al., 1980]. The two lesions are often found in the same patient; from 7% to 26% of women with vulvar squamous tumours are found to have one or more condylomata. These observations, however, only represent case series which may not be representative of any defined population. Though it has not been determined that this coexistence is beyond that which could be expected on the basis of chance, the fact that the lesions have been observed on a microscopic level to merge into one another [Crum et al., 1982] suggests more than mere coincidence. Indeed, some condylomata have been observed to undergo malignant change over time [Kovi et al., 1974]. The purpose of the present study was to quantify the degree to which condylomata acuminata occur

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

Multiple primary tumours in women with vulvar neoplasms: a case-control study

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.

IUDs and pelvic inflammatory disease

We sought to determine whether women with in situ or invasive squamous cell vulvar cancer were more likely than other women to have had a previous or concurrent tumour at other anogenital sites. One hundred and fifty-eight women with vulvar cancer were identified who were first diagnosed during 1980-1985, were ages 18-79 years at that time, and were residents of one of three counties in western Washington. Two control groups were selected: (1) from records of hospital pathology departments, a sample of 113 women with certain benign conditions of the vulva; (2) through random digit dialing, a sample of 212 women from the general population of these counties. Information on a history of other cancers, and on sexual, reproductive, medical, and demographic characteristics was collected from cases and controls in at-home interviews. Cases were more likely to report a history of other anogenital cancers than were controls, with relative risks of 3.5-29.8, depending on the type of case group and type of control. These associations were not explained by case-control differences in demographic characteristics or frequency of cervical screening. On the other hand, prior or concurrent non-anogenital cancers were equally common in cases and controls. These results support the hypothesis that the different anogenital cancers have at least one aetiology in common.