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At least 163 records · Page 9Linked to original sources

Pregnancy rates during long-term use of copper IUDs.

990 cases of women using standard copper IUDs (Cu 7; Cu T; Multiload) up to a maximum period of 8 years have been analyzed statistically. The long-term use effectiveness was evaluated mainly by using statistical methods (life table). Pregnancy rates decreased during the whole period of observation but more evidently after 2 years of use. It is recommended that medicated IUDs, free of side effects, be exchanged only after 5 years of use, corrosive changes being not too far advanced after this period. New IUD models are less likely to be subject to corrosion and will therefore need to be replaced less frequently.

Age Factors↗

A comparative clinical trial of Norinyl 1/35 versus Brevicon in Rio Clara, Brazil.

A comparative clinical trial of two combined oral contraceptives (OCs) with equivalent estrogen content, but different amounts of progestogens, was conducted at the Centro Medico Especializado em Planejamento Familiar in Rio Clara, Brazil. The study was designed to determine the differences in discontinuation rates between Norinyl 1/35 (Syntex) and Brevicon (Syntex) as well as the frequency of selected side effects which might contribute to method discontinuation. Both OCs contain 0.035 mg of ethinyl estradiol; Brevicon contains 0.5 mg and Norinyl 1/35 contains 1 mg norethindrone. Three-hundred women enrolled in the study were randomly assigned to either the Norinyl 1/35 or Brevicon OCs and follow-up visits were scheduled at 1, 4, 8 and 12 months after admission. Intermenstrual bleeding was reported by significantly more women in the Brevicon group than in the Norinyl group (p less than 0.05), and significantly more Brevicon users reported an increase in intermenstrual bleeding. At the end of the study period, no differences were found between the two OC groups in terms of discontinuation rates, but a large number of women in each group discontinued for menstrual problems. The total discontinuation rates at 11 months for both groups were extremely high: 68.2 for the Norinyl 1/35 group and 75.2 for the Brevicon users. The largest group of discontinuations were comprised of those discontinuing for menstrual problems, other personal reasons, planned pregnancy and side effects.

Adult↗

Prevention of deaths from harmful drinking in the United States: the potential effects of tax increases and advertising bans on young drinkers.

OBJECTIVE: Harmful alcohol consumption is a leading cause of death in the United States. The majority of people who die from alcohol use begin drinking in their youth. In this study, we estimate the impact of interventions to reduce the prevalence of drinking among youth on subsequent drinking patterns and alcohol-attributable mortality. METHOD: We first estimated the effect of public health interventions to decrease harmful drinking among youth from literature reviews and used life table methods to estimate alcohol-attributable years of life lost by age 80 years among the cohort of approximately 4 million U.S. residents aged 20 in the year 2000. Then, from national survey data on transitions in drinking habits by age, we modeled the impact of interventions on alcohol-attributable mortality. RESULTS: A tax increase and an advertising ban were the most effective interventions identified. In the absence of intervention, there would be 55,259 alcohol-attributable deaths over the lifetime of the cohort. A tax-based 17% increase in the price of alcohol of dollar 1 per six pack of beer could reduce deaths from harmful drinking by 1,490, equivalent to 31,130 discounted years of potential life saved or 3.3% of current alcohol-attributable mortality. A complete ban on alcohol advertising would reduce deaths from harmful drinking by 7,609 and result in a 16.4% decrease in alcohol-related life-years lost. A partial advertising ban would result in a 4% reduction in alcohol-related life-years lost. CONCLUSIONS: Interventions to prevent harmful drinking by youth can result in reductions in adult mortality. Among interventions shown to be successful in reducing youthful drinking prevalence, advertising bans appear to have the greatest potential for premature mortality reduction.

Adult↗

Personal hormone monitoring for contraception.

OBJECTIVE: To determine the effectiveness and acceptability of personal hormone monitoring for contraception. DESIGN: A large prospective study was carried out on personal hormone monitoring for contraception when used with abstinence during the identified fertile days. SETTING: Three country study under the auspices of the departments of Obstetrics and Gynaecology of the Universities of Birmingham, Dublin and Dusseldorf SUBJECTS: Seven hundred and ten women, median age 30, were recruited from the general population. They were required to have regular menstrual cycles (23-35 days) and to be delaying their next pregnancy. INTERVENTIONS: Personal hormone monitoring consists of a hand held monitor and disposable test sticks which measure changes in urinary concentrations of oestrone-3-glucuronide and luteinising hormone. An algorithm estimated the fertile days which were displayed by a red light. OUTCOME MEASURES AND RESULTS: One hundred and sixty two pregnancies occurred in 7209 cycles of use, of which 67 were method related pregnancies. The 13 cycle life-table method pregnancy rate (95 per cent CI) was 12. 1 per cent (9.3-14.8). The system allowed analysis of the effect of changes to the algorithm to modify the defined fertile period. As a result the algorithm was changed to increase the median warning of the luteinising hormone surge to six days. With the revised algorithm, half of the method pregnancies would have been prevented giving a calculated method pregnancy rate of 6.2 per cent (4.2-8.3) and method efficacy of 93.8 per cent. The continuation rate after 13 cycles was 78 per cent. CONCLUSION: Personal hormone monitoring proved simple to use and will be of value to women who do not want to use other methods of contraception.

Adolescent↗

Contraceptive efficacy of lactational amenorrhoea.

Pregnancy is rare among breastfeeding women with lactational amenorrhoea. The lactational amenorrhoea method (LAM) is the informed use of breastfeeding as a contraceptive method by a woman who is still amenorrhoeic, and who is not feeding her baby with supplements, for up to 6 months after delivery. Under these three conditions, LAM users are thought to have 98% protection from pregnancy. It can be difficult, however, to determine when supplementation of the baby's diet begins. We have analysed data from nine studies of the recovery of fertility in breastfeeding women to assess the effectiveness of lactational amenorrhoea alone, irrespective of whether supplements have been introduced, as a fertility regulation method post partum. Cumulative probabilities of ovulation during lactational amenorrhoea were 30.9 and 67.3 per 100 women at 6 and 12 months, respectively, compared with 27.2 at 6 months when all three criteria of the LAM were met. Cumulative pregnancy rates during lactational amenorrhoea were 2.9 and 5.9 per 100 women at 6 and 12 months, compared with 0.7 at 6 months for the LAM. The probability of pregnancy during lactational amenorrhoea calculated from these studies is similar to that of other modern contraceptive methods, and it seems reasonable for a woman to rely on lactational amenorrhoea without regard to whether she is fully or partly breastfeeding. So that amenorrhoea and fertility suppression can be maintained, counselling about good breastfeeding and weaning practices remains important.

Actuarial Analysis↗

Immediate postpartum insertion of a copper-wired intrauterine contraceptive device, the MLCu250.

The MLCu250, a copper-wired intrauterine contraceptive device, was inserted in 600 women immediately after delivery of the placenta. Thirty months after insertion, 9843 woman months of experience were computerized and the data analysed according to the life-table method. The gross cumulative pregnancy and expulsion rates were 1.3 and 6.0 respectively. No serious complications were observed and the puerperium was uncomplicated.

Adult↗

Family and fertility careers of Polish females: a semi-parametric and life table approach.

"In this paper an evaluation has been made using the semi-parametric analysis and life table method of changes in the process of formation and dissolution of families in Poland, and changes in fertility careers by cohorts. An answer was sought to the following questions: What are the factors significantly determining the process studied? What differences appear between cohorts?"

Cohort Studies↗

Invasive cervical cancer after conservative therapy for cervical intraepithelial neoplasia.

BACKGROUND: Conservative outpatient therapy for cervical intraepithelial neoplasia (CIN) by ablative or excisional techniques is widely used. The main objective of this treatment is the prevention of invasive cervical cancer. We assessed the rate of invasive disease and the duration of the risk of developing invasive cervical cancer after such treatment. METHODS: Four UK centres have used life-table methods to analyse the long-term results of conservative treatment of CIN. We combined and updated data from these studies to investigate the rate of invasive disease after treatment and the duration of that risk. FINDINGS: The data comprised 44 699 woman-years of follow-up, with 2116 women under observation 8 years after treatment. 33 women developed invasive cancer, 14 of whom had microinvasion. The cumulative rate of invasion 8 years after treatment was 5.8 per 1000 women and the rate of invasive cancer during this period was 85 (95% CI 60-119) per 100,000 woman-years. The risk of developing cancer did not change throughout the 8 years of follow-up. INTERPRETATION: These data show that conservative outpatient therapy in women with CIN reduces the risk of invasive cancer of the cervix by 95% during the first 8 years after treatment. However, even with careful, long-term follow-up, the risk of invasive cervical cancer among these women is about five times greater than that among the general population of women throughout that period. Careful follow-up is essential for at least 10 years after conservative treatment of CIN.

Adult↗

Worldwide variations in the lifetime probability of reproductive cancer in women: implications of best-case, worst-case, and likely-case assumptions about the effect of oral contraceptive use.

Cancer incidence in countries representative of three patterns of reproductive cancer and age-specific mortality was used to estimate the effect of oral contraceptive use on the lifetime probability of reproductive cancer under three sets of assumptions about the effects of oral contraceptives. Under the set of assumptions considered likely, oral contraceptives were estimated to reduce or increase only slightly the lifetime probability of any reproductive cancer in each setting. Under worst-case assumptions, oral contraceptives were estimated to increase the lifetime probability of reproductive cancer only modestly in settings with low cancer rates and in settings with high rates of breast, ovarian, and endometrial cancer, but it might have a large impact on lifetime probability of reproductive cancer in settings with high cervical cancer rates. Under best-case assumptions, oral contraceptives were estimated to decrease the lifetime probability of reproductive cancer in each setting; this reduction was estimated to be greatest in settings where endometrial and ovarian cancer incidence are high.

Adolescent↗

Should women with familial ovarian cancer undergo prophylactic oophorectomy?

OBJECTIVES: To estimate the lifetime probabilities of ovarian cancer in women from families with hereditary ovarian cancer syndromes and those with a family history of ovarian cancer, and to assess the needs for prevention and surveillance in such women. DATA SOURCES: We searched for studies of familial ovarian cancer published since 1966 and used ovarian cancer incidence data from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute. METHODS: Pooled estimates of relative risk of ovarian cancer among women with a family history of ovarian cancer were derived using statistical methods based on fixed effects. Modified life-table methods were used to estimate the lifetime probability of ovarian cancer. DATA SYNTHESIS: The lifetime probability of ovarian cancer increases from about 1.6% in a 35-year-old woman without a family history of ovarian cancer to about 5% if she has one relative and 7% if she has two relatives with ovarian cancer. The lifetime probability may decrease to about 3-4% if she takes oral contraceptives for 5-9 years. Women from families with hereditary ovarian cancer syndromes may have as high as a 50% lifetime risk of ovarian cancer. CONCLUSIONS: The risk of ovarian cancer in women from families with hereditary ovarian cancer syndromes is sufficiently high to warrant prophylactic oophorectomy. Among women with one relative with ovarian cancer, the lifetime probability of ovarian cancer is not high enough to recommend oophorectomy. However, some women may choose oophorectomy depending on their attitudes concerning risk-taking, surgery, and hormone replacement. Oral contraceptives should be considered as preventive therapy to decrease the risk of ovarian cancer in women with a family history of ovarian cancer.

Adult↗

Five years' experience with levonorgestrel-releasing IUDs.

Two levonorgestrel-releasing IUDs and a copper-releasing IUD of the same shape were studied in a randomized comparative study over five years. The levonorgestrel-releasing IUDs released 20 micrograms or 30 micrograms per day. The Pearl index during the 10,600 woman-months of LNG-IUD use was 0.11. The control device releasing copper had a Pearl index of 1.6. The amount and duration of menstrual bleeding was greatly reduced, leading to a high incidence of oligo- or amenorrhea. The continuation rate in this pioneer trial was 53 per 100 users for the levonorgestrel-releasing IUD (LNG-IUDs) and 50 per 100 users for the copper-releasing IUD (Nova T). The removal rates for reasons other than amenorrhea were not significantly different. Discontinuation because of amenorrhea occurred during the first two years, the cumulative termination rate for this reason was 11.6 per 100 users at five years. The LNG-IUDs removed for investigation after five years of use revealed that the devices contained about 40 percent of the original load. The effective lifespan of the device has been demonstrated by this study to be five years; the residual steroid gives an additional safety period of two more years. The LNG-IUD is a highly effective reversible contraceptive method, which strongly reduced the amount and duration of bleeding. During the first two months there is scanty but frequent spotting which, like the high incidence of oligo- and/or amenorrhea, requires counselling of health personnel and women using LNG-IUDs.

Adult↗

Analysis of underlying and multiple-cause mortality data.

"A variety of life table models were used for the analysis of the (1984-86) Kuwaiti cause-specific mortality data. These models comprised total mortality, multiple-decrement, cause-elimination, cause-delay and disease dependency. The models were illustrated by application to a set of four chronic diseases: hypertensive, ischaemic heart, cerebrovascular and diabetes mellitus. The life table methods quantify the relative weights of different diseases as hazards to mortality after adjustment for other causes. They can also evaluate the extent of dependency between underlying cause of death and other causes mentioned on [the] death certificate using an extended underlying-cause model." (SUMMARY IN FRE AND ITA)

Asia↗

[Application of multistate model to the analysis of relationship between cumulative occupational exposure and occurrence of disease].

The relationship between cumulative exposure and response used to be estimated by using the two state life table method. But since the occurrence of the response is related to the time factor after exiting exposure, this method may not provide correct description of this relationship. Based on multiple state model, this paper put forward a new method which modifies the effect of the time after exiting exposure on this relationship. The data from a cohort of 1113 underground male workers in a tin mine was taken as an example to illustrate the merit of this method.

Humans↗

Further experience with the saphenous vein used in situ for arterial bypass.

Ongoing experience with use of the saphenous vein in situ as in infrainguinal arterial bypass is presented. One hundred eighty-three bypasses were performed for limb-threatening ischemia, 92 of which were to the popliteal artery, either isolated or in continuity with one or more tibial vessels, and 91 bypasses were carried to single tibial vessels below the termination of the popliteal artery. The results were analyzed by the life table method and show an overall patency rate of 89.8 percent at 3 to 4 years. Separate life table analysis of the tibial bypass group showed a patency rate of 83 percent at 3 to 4 years. Special emphasis is placed on the ability to use veins less than 4 mm in diameter, which comprise 40 percent of those used in these procedures. The superior results provided by the in situ method are explained in part by experimental observations which show that endothelial stability is completely preserved by this method but is severely disturbed during the process of vein removal and reversal.

Aged↗

Aggressive therapy for locoregional recurrence after mastectomy in stage II and III breast cancer patients.

BACKGROUND: To determine if aggressive treatment of locoregional recurrence affects survival, we retrospectively analyzed the clinical outcome of 69 breast cancer patients who developed locoregional disease as their first episode of recurrence following mastectomy and adjuvant chemotherapy. METHODS: Patients were identified from among 1,707 stage II and III breast cancer patients who enrolled in five different doxorubicin-based adjuvant chemotherapy protocols at The University of Texas M. D. Anderson Cancer Center from 1975 to 1986. Sixty-nine evaluable patients who had a locoregional recurrence as the first site of relapse after mastectomy formed the study group. Multifactorial analysis of clinical and histopathological characteristics of both the primary tumor and the subsequent recurrence was performed using a logistic regression method. Survival analysis was performed using an actuarial life-table method calculated from the date of registration into the adjuvant therapy protocols. RESULTS: Median follow-up was 6.6 years. Two factors significantly affected survival: recurrence of disease during or after adjuvant treatment of the primary and whether the patient was rendered disease free after recurrence. CONCLUSIONS: Stage II and III breast cancer patients who have locoregional recurrence after adjuvant chemotherapy and can be rendered disease free may have a better survival rate. Aggressive treatment of locoregional recurrence including complete surgical excision should be considered in this subgroup of patients.

Antineoplastic Combined Chemotherapy Protocols↗