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Biomedical subjects

N C Lee

Publications and source records attributed to N C Lee.

At least 109 records · Page 6Linked to original sources
PubMed1987

Reproductive history and breast cancer in a population of high fertility, Costa Rica, 1984-85.

The relationship between breast cancer and women's reproductive history in Costa Rica was analyzed using logistic regression methods on data from 171 breast cancer cases and 826 population-based controls aged 25-58 years. The risk of breast cancer in nulliparous women under age 45 was 3 times that for parous women in the same age group. Women over 44 years of age with a parity greater than 4 had a risk of breast cancer of 0.3 compared to women of the same age but with a parity of 1-4. Neither breast-feeding nor birth interval showed an overall association with breast cancer independent of parity. Women with early age at first birth had a lower relative risk of breast cancer than women aged 20-24 at first birth, but only in two subgroups--women aged 45 and over and women with parity 1-4. Women without a completed pregnancy in the last 20 years had an elevated relative risk. However, results are not conclusive because some information is probably distorted by recall errors. Declines in fertility rates in the 1960s and 1970s may result in an increase of 30% in breast cancer incidence in Costa Rica between 1980 and the year 2000, according to the relative risks found in this study. In contrast, the effect of childlessness will probably not produce significant changes in national breast cancer trends.

Adult↗
PubMed1987

Generics in trouble.

Explore the source record for details and available documents.

Pharmaceutical Preparations↗
PubMed1987

The risk of breast cancer in postmenopausal women who have used estrogen replacement therapy.

We studied the association between estrogen replacement therapy (ERT) and the risk of breast cancer as part of the Cancer and Steroid Hormone Study. All subjects in the analysis were postmenopausal women enrolled from eight geographic areas. Women 25 to 54 years old with newly diagnosed breast cancer were identified through population-based tumor registries and diagnosed between Dec 1, 1980, and Dec 31, 1982. Controls were selected from the same eight geographic areas by the random digit dialing of residential telephone numbers. Analyses included 1369 cases and 1645 controls. Among women with bilateral oophorectomy, the relative risk of breast cancer for women who had ever used ERT was 1.3, compared with women who had never used ERT. Among women who had undergone hysterectomy but who still had at least one ovary, the relative risk was 1.1; among women who reported a natural menopause, the relative risk was 0.8. Overall, the risk of breast cancer did not appear to increase appreciably with increasing ERT duration or latency, even for durations and latencies of 20 years or longer.

Adult↗
PubMed1987

Cigarette smoking and the risk of epithelial ovarian cancer.

Cigarette smoking may affect each of the currently proposed mechanisms of ovarian carcinogenesis. Whether cigarette smoking has any effect on the development of ovarian cancer has not been adequately evaluated. To study this issue, the authors examined data from the Cancer and Steroid Hormone Study, a multicenter, case-control study of gynecologic cancers conducted between December 1, 1980, and December 31, 1982, in eight geographic areas of the United States. This analysis utilized data on 494 women with newly diagnosed epithelial ovarian cancer and 4,238 population-based control women 20-54 years of age. There was no association of epithelial ovarian cancer with dose of cigarette smoking, age smoking started, time since smoking started, or time since smoking last occurred. Simultaneous adjustment for age, parity, history of oral contraceptive use, and other potentially confounding factors did not alter these results.

Adult↗
PubMed1987

A case-control study of breast cancer and hormonal contraception in Costa Rica.

By 1981, 11% of married women in Costa Rica ages 20-49 years had used depot-medroxyprogesterone acetate (DMPA) and 58% had used oral contraceptives (OCs). Since 1977, the Costa Rican Ministry of Health has maintained a nationwide cancer registry. These circumstances provided an opportunity for a population-based, case-control study of DMPA, OCs, and breast cancer in Costa Rica. Cases were 171 women ages 25-58 years with breast cancer diagnosed between 1982 and 1984; controls were 826 women randomly chosen during a nationwide household survey. Cases and controls were interviewed with the use of a standard questionnaire covering their reproductive and contraceptive histories. Logistic regression methods were used to adjust for confounding factors. While few cases or controls had ever used DMPA, DMPA users had an elevated relative risk (RR) estimate of breast cancer of 2.6 (95% confidence limits = 1.4-4.7) compared with never users. However, no dose-response relationship was found; even the group of women who had used DMPA for less than 1 year had an elevated RR estimate (RR = 2.3; 95% confidence limits = 1.0-5.1). In contrast, OC users had no elevation in RR compared with never users (RR = 1.2; 95% confidence limits = 0.8-1.8). The results of the DMPA analysis are inconclusive. Before decisions are made on whether to continue providing this effective contraceptive method, other ongoing studies will need to confirm of refute these findings.

Adult↗
PubMed1986

Alcohol consumption and ovarian cancer risk.

To study the influence of alcohol consumption on the risk of ovarian cancer in women under age 55, the authors examined data collected in a multicenter, population-based case-control study--the Centers for Disease Control's Cancer and Steroid Hormone Study. Between August 1981 and December 1982, 433 women 20-54 years of age with newly diagnosed ovarian cancer and 2,915 women 20-54 years of age selected at random from the same geographic areas were asked about their consumption of alcoholic beverages during the previous five years. Women who drank any alcohol during the five-year period had a risk of ovarian cancer of 0.9 (95% confidence interval (CI) = 0.7-1.2) compared with nondrinkers. Risk was not associated with the type of alcoholic beverage consumed, nor were the results affected by controlling for demographic characteristics and oral contraceptive use. Although there was no association between moderate alcohol consumption and ovarian cancer, women who drank more than about 20 drinks per week had a relative risk of ovarian cancer of 0.5 (95% CI = 0.2-0.9) compared with women who did not drink.

Adult↗
PubMed1986

Microbes, warfare, religion, and human institutions.

A significant number of practicing microbiologists are not aware of the historical impact of infectious agents on the development of human institutions. Microbes have played a profound role in warfare, religion, migration of populations, art, and in diplomacy. Boundaries of nations have changed as a result of microbial diseases. Infectious agents have terminated some kingdoms and elevated others. There is a need for microbiologists to have a historical perspective of some of the major ways in which a pathogen may influence civilized populations. Conditions may exist in contemporary society for a repeat of some of the kinds of plagues suffered by previous societies. The purpose of this paper is to review examples of situations where pathogenic microbes have forced societal modifications on centers of human population.

Animals↗
PubMed1985

Hysterectomy performed within 1 year after tubal sterilization.

In the United States, approximately 650,000 women of reproductive age undergo tubal sterilization each year and some of these women later have hysterectomies. Little is known about risk factors for having hysterectomy after tubal sterilization. For examination of this issue, we analyzed data from the Collaborative Review of Sterilization, an ongoing multicenter prospective study designed to assess the safety and efficacy of female sterilization operations. In 1979 and 1980, 4002 women 15 to 44 years of age had interval tubal sterilization; of these women, 64 had hysterectomies within 15 months, which yielded a cumulative incidence of 1.6%. Women with a history of menstrual complaints, leiomyomata, ovarian cysts, or endometriosis before their tubal sterilization had an increased risk of hysterectomy, compared with women without such a history. However, 98% of women with a history of these conditions did not have a hysterectomy within 15 months after tubal sterilization. Further follow-up of these women should help to better delineate their long-term risks.

Adolescent↗
PubMed1984

Confirmation of the preoperative diagnoses for hysterectomy.

Few previous studies have examined the relationship between the preoperative and pathologic diagnoses for hysterectomy. To determine the percentage of preoperative diagnoses that were confirmed by pathologic examination, we analyzed data from the Collaborative Review of Sterilization, a multicenter study of hysterectomies and tubal sterilizations in women aged 15 to 44 years. Data were collected from patient interviews and chart reviews. Of the 1851 women included in this study, 1283 (69%) had abdominal hysterectomies and 568 (31%) had vaginal hysterectomies. Overall, 52% of the hysterectomies were performed for a preoperative diagnosis that could potentially be confirmed by pathologic examination. Pathologic examination actually confirmed the preoperative diagnosis of endometrial hyperplasia in 95% of the cases, cervical intraepithelial neoplasia in 89%, leiomyomas in 84%, pelvic inflammatory disease in 75%, adenomyosis in 48%, and endometriosis in 47%. Among all of the potentially confirmable diagnoses, 80% were confirmed. The remaining 48% of the women who had hysterectomies had preoperative diagnoses that were not amenable to confirmation by pathology. Most of these were for one of three diagnoses: menstrual bleeding disorders, pelvic pain, or pelvic relaxation. In 47% of these cases, pathologic examination showed leiomyoma or adenomyosis; no abnormalities were found in 38% of these cases.

Adolescent↗
PubMed1984

Report of a high pregnancy rate after sterilization with the Bleier clip.

We investigated a report of a pregnancy rate of 7.3% after tubal sterilization procedures with the Bleier clip in one physician's practice. A review of ongoing clinical investigations of this method of tubal sterilization revealed a failure rate of 0.3%. Our investigation determined that misapplication of the clips was the most probable explanation for the high failure rate, though how the misapplications occurred is not known. The Bleier clip is probably an effective method of tubal occlusion, but close monitoring is needed to determine whether the high failure rate reported here is an isolated instance or a recurrent problem.

Evaluation Studies as Topic↗
PubMed1984

Tubal sterilization in women 15-24 years of age: demographic trends in the United States, 1970-1980.

Between 1970-1980, approximately 942,000 women 15-24 years of age underwent tubal sterilization in the United States. These women represented about 17 per cent of all women ages 15-44 years who underwent tubal sterilization in the United States during this 11-year period. During 1970-1980, sterilization rates rose steadily from three per 1,000 to 11 per 1,000 for women in the 20- to 24-year age group, but remained stable at less than one per 1,000 for women in the 15- to 19-year age group. For each year, rates for Black women were greater than those for White women. Sterilization rates increased over the time period for both currently and previously married women, but remained low for never-married women. Most tubal sterilizations were performed after delivery of an infant.

Adolescent↗