Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Life Table Method”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1985

Umbilical vein bypass in patients with severe lower limb ischemia: a report of 121 consecutive cases.

In 112 patients with severe ischemia of the lower limb and without a suitable saphenous vein, 99 femoropopliteal and 22 femorodistal bypass procedures were performed with the modified human umbilical vein (Biograft, Meadox Medicals Inc., Oakland, N.J.). Seventy-eight percent of the operations were performed for limb salvage. In the remaining 22% the indication was severe disabling claudication. Forty-nine percent of the patients had previously undergone arterial reconstruction of the extremity in question. In 36% the distal anastomosis was to the popliteal artery above the knee, in 46% to the popliteal artery below the knee, and in 18% to one of the crural arteries. It was mandatory to perform an additional proximal reconstruction in 38% of the extremities. The observation time ranged from 6 to 60 months, with a mean of 24 months. Two patients died within the first month. The overall cumulative patency rate calculated by the life table method was 67.7% at 1 year, 61.2% at 2 years, and an unchanged 56.6% at 3 to 5 years. The cumulative patency rate in the limb salvage group was higher (58.6%) than the patency rate of the grafts implanted for claudication (46.5%, not significant). Graft patency decreased the more peripherally the distal anastomosis was situated, but we could demonstrate neither a significant relationship between graft patency and runoff nor any prognostic significance in the peroperatively measured flow values. Limb salvage calculated by the life table method was 86% at 1 year and 75.4% at 5 years. It is concluded that the umbilical vein graft is an acceptable alternative for bypass grafting in patients without a suitable autogenous vein.

Aged↗
PubMed1997

Breast cancer risk estimation in families with history of breast cancer.

Among 288 breast cancer patients (118 with bilateral disease and 165 with diagnosis before 40 years of age), we identified 26 families with a history of breast cancer, including a minimum of three first- or second-degree relatives. Complete pedigrees with verified malignancy data from the Finnish cancer registry were constructed for 22 families. The median age at breast cancer diagnosis of the young probands (< 40 years of age) was 35 years and of bilateral probands was 54 years. The relatives of the young probands were diagnosed with breast cancer at a younger age (median age 54 years) than the relatives of the older (bilateral) probands (median age 60 years). Standard life-table methods were used to compare the risk of breast cancer in the family members with that of the general population. Among the relatives of the young probands, the increased breast cancer risk occurred in the early post-menopausal period, whereas the risk estimate for the relatives of the bilateral probands closely followed that of the general population. In both groups, however, those family members reaching the age of 80 years had a cumulative probability of over 50% of developing breast cancer. The standard life-table method proved useful when assessing the age-specific risk for familial breast cancer, taking into account numerous family members as well as their age at disease onset. This kind of analysis can be performed in populations for which reliable cancer registry data are available. It provides a useful tool for selecting individuals for imaging and mutation screening, counselling and experimental chemoprevention programmes.

Adult↗
PubMed1987

Use of second-look laparotomy in the management of patients with ovarian epithelial malignancies.

Between June 1976 and January 1986, 94 evaluable patients with stage I-IV disease underwent second-look laparotomy as part of their treatment for ovarian epithelial carcinomas. Stage and residual tumor size after initial debulking surgery demonstrated a significant association with absence of disease at reexploration. Forty-nine patients (52%) had no evidence of disease at second-look laparotomy. Thirty patients (32%) had macroscopic residual tumor, and 15 patients (16%) had microscopic disease at reexploration. Patients with a negative second-look laparotomy had an excellent prognosis; uncorrected 2- and 5-year survival rates exceed 90%. None of the patients with stage I or II disease developed recurrent tumor after a negative second-look laparotomy. However, 7 of the 25 (28%) patients with stage III disease and a negative second-look have demonstrated recurrent carcinomas. Recurrences were documented from 15.4 to 51.7 months after second-look laparotomy and were located within the abdominal cavity. Life table methods demonstrated improved survival for patients with microscopic disease as compared to those with gross tumor at second-look survey. Both groups had similar mean patient ages and tumor stage distributions. Patients with microscopic residual disease had uncorrected 2- and 5-year survival rates of 76 and 64%. The 2-year uncorrected survival rate for patients with gross tumor at second-look laparotomy was 25%. Thirty patients with macroscopic disease at second-look laparotomy underwent a repeat attempt at tumor debulking. Seventeen patients completed second-look surgery with residual disease less than 1 cm in maximum dimensions. Life table methods demonstrated improved survival when residual disease was less than 1 cm. Regardless of residual tumor size after reexploration, patients with gross tumor had a worse survival than those with microscopic disease.

Adult↗
PubMed1998

The natural history of asymptomatic moderate internal carotid artery stenosis by duplex ultrasound.

The purpose of this study was to determine the rate of progression of the degree of carotid stenosis and to determine the risk of continued observation in a group of asymptomatic patients with moderate stenosis of at least one internal carotid artery. Between 1989 and 1994, 2130 patients were found to have 60-79% stenosis of at least one internal carotid artery following a duplex ultrasound examination in the authors' vascular laboratory. Of these, 465 patients (255 men, 210 women) were asymptomatic and had more than one ultrasound examination, and they form the basis of this retrospective review. The mean +/- SD age was 68.8 +/- 9.0 years. The mean +/- SD number of ultrasound examinations was 3.1 +/- 1.4 (range 2-11). The mean +/- SD follow-up was 24.4 +/- 17.6 months (range 2-79 months). Over the period of follow-up 72 patients (15.5%) progressed to 80-99% stenosis (n = 71) or to occlusion (n = 1). The estimated percentage of patients who progressed by life table methods were 5 +/- 1% at 1 year, 11 +/- 2% at 2 years and 20 +/- 3% at 3 years. There was no statistically significant difference in the rate of progression in men compared with women. Twenty-one patients had a late ipsilateral TIA or stroke. Five out of 72 patients (6.9%) who progressed had a late ipsilateral TIA compared with nine out of 393 patients (2.3%) who did not progress (estimated risk ratio 16.1, P = 0.0001). Four out of 72 patients (5.6%) who progressed had a late ipsilateral stroke compared with three out of 393 patients (0.76%) who did not progress (estimated risk ratio 23.6, p = 0.0002). The cumulative ipsilateral stroke rate using life table methods was 0.22% at 1 year, 1% at 2 years and 2.4% at 3 years. In a large cohort of asymptomatic patients, the frequency of progression of 60-79% internal carotid artery stenosis was 5% at 1 year, 11% at 2 years and 20% at 3 years. Patients who progressed were more likely to have symptoms, but the rate of unheralded stroke was relatively low over a 3-year time period. Surveillance carotid ultrasound examinations should be performed in patients with moderate carotid stenosis. Because of the lack of clear benefit, carotid endarterectomy for asymptomatic 60-79% internal carotid artery stenosis cannot be justified.

Aged↗
PubMed1992

[Analysis of chronic excretors of Mycobacterium bacilli in Aichi Prefecture].

Among the patients diagnosed as having pulmonary tuberculosis who were newly admitted to six major tuberculosis centers in Aichi Prefecture during the period from January 1, 1982 to December 31, 1986, 73 patients were chronic excretors of Mycobacterium bacilli (chronics), whose sputum cultures tested positive at both 11 and 12 months after admission. In this study, those 73 patients were analyzed in March 1988. If the patient was still hospitalized at that time, the patient was re-evaluated six months later. The life table method was used for analysis of clinical procedures. For the analysis of risk factors for chronics, 37 patients who were treated after 1971 when RFP was available for treatment were used. The results in this study are as follows: 1. A total of 49.3% of the patients were determined chronics (those who had initial chemotherapy before 1970 when RFP was not available). This result suggests that the use of RFP may contribute to the reduction of chronics. 2. Patient delay in diagnosis, as well as irregular chemotherapy, was one of the factors for the development of chronics. 3. In the chronics, many patients showed severe findings in their chest X-rays, high bacillary counts in the sputum, and low drug-sensitivity bacilli when treated with the major anti-tuberculosis drugs. 4. The rate of chronics from newly admitted patients with positive sputum cultures following the initial chemotherapy treatment was 1.3%. This rate could increase following longer observation periods. 5. Chronics were more prevalent in patients with Type I (extensive cavitary type) findings in the chest X-rays, and positive sputum smears for Mycobacterium bacilli in the clinical findings when compared with all newly registered active tuberculosis patients during the same period in Aichi Prefecture. 6. Concerning the outcome, 55 patients were discharged (17 improved; 13 personally released; 25 deceased) while 18 remain hospitalized. Among those discharged patients, 17 patients were released as a result in improved health while 25 died. These results indicate poor prognosis. Using the life table method, the estimated mortality rate is 49.7%, and the negative sputum rate is 30.5% five years later. 7. Using a multivariate analysis on the prognosis, the risk factor was greatest for poor prognosis for those patients who had Type I findings in their chest X-rays, initial chemotherapy before 1970, complications, and that were male. 8. The patients with improved health, were more sensitive to the drugs applied when compared to the fatal patients. 9. Careful chemotherapy during the first two years may contribute to the reduction of chronics.

Adult↗
PubMed1994

Long-term outcome for 120 Japanese patients with Takayasu's disease. Clinical and statistical analyses of related prognostic factors.

BACKGROUND: Patients with Takayasu's disease, a chronic inflammatory arteriopathy of unknown cause, have variable clinical courses, and predictors of the long-term outcome are not well understood. We studied prognostic factors of this disease, based on follow-up results, and a new prognostic classification was proposed. METHODS AND RESULTS: Life-table methods and Cox regression analyses were applied to clinical data on 120 patients who had been prospectively followed for a median of 13 years (range, 1 month to 34 years). The overall survival rate at 15 years after the diagnosis was 82.9% and remained the same for the remainder of the follow-up period. Univariate Cox analyses revealed that of the six dichotomous variables evaluated at diagnosis, four were statistically significant predictors, including complications (Takayasu's retinopathy, hypertension, aortic regurgitation, and aneurysm), pattern of the past clinical course, age of the patient, and calendar year of diagnosis. Thus, the 15-year survival was 66.3% versus 96.4% for patients with and without a major complication, 67.9% versus 92.9% for patients with and without a progressive course, 58.3% versus 92.7% for age > 35 years and < or = 35 years, and 79.9% versus 96.5% for patients diagnosed in 1957 through 1975 and in 1976 through 1990, respectively. The delay in diagnosis and the erythrocyte sedimentation rate (ESR) were of marginal significance. The multivariate Cox analysis showed that only two of the above variables were statistically independent predictors, ie, the major complication and the progressive course. In addition to these two factors, ESR was the third predictor, if the Cox stepwise elimination procedure was performed. These three predictors used in various combinations made a total of 1822 classifications theoretically feasible. Of these, a three-stage classification was selected as the best one, based on the Akaike information criterion. The presence of both major complication and progressive course (stage 3) was the worst prognostic indicator (43% survival at 15 years). In contrast, no patient died who had neither of these manifestations or who had a progressive course but an elevated ESR as well (stage 1). CONCLUSIONS: The long-term outcome for patients with Takayasu's disease seems best predicted by two major prognostic factors, ie, complications and the pattern of the past clinical course, as well as by ESR. Aggressive medical and surgical treatment may be considered for patients with a major complication and a progressive course (stage 3).

Adolescent↗
PubMed1998

Invasive cancer after treatment of cervical intraepithelial neoplasia.

This review discusses the risk of invasive cancer following treatment for cervical intraepithelial neoplasia (CIN). The emphasis is on methods in current use and the risks are calculated with life table methods. Large, long-term follow up studies which use life table analysis show clearly that invasive recurrences continue to appear at a relatively steady rate for at least 8 years after treatment for CIN. The risk remains 4 to 5 times greater than in the background population throughout this period. It would seem prudent to continue to offer these women increased surveillance with annual smears during this time of increased risk. All modern methods of outpatient treatment are highly effective in preventing invasive cancer of the cervix if they are used skillfully with an understanding of the disease being treated. The thoughtless use of beguilingly easy methods will lead only to disaster.

Cervix Uteri↗
PubMed1980

Second malignancies in Hodgkin's disease: a complication of certain forms of treatment.

A total of 764 patients with Hodgkin's disease treated with radiotherapy (RT) or chemotherapy or both were reviewed 3-186 months (median 43 months) after initial treatment to assess the incidence of second malignancies. Incidence of solid tumours and acute non-lymphoblastic leukaemia (ANLL) were calculated by a life-table method and percentages of patients affected derived from life-table plots. Within 10 years after initial treatment the overall incidence of second solid tumours was 7.3%, and over a comparable period 2.4% of patients developed ANLL. Solid tumours occurred only in patients given RT with or without adjuvant chemotherapy, and ANLL occurred only after treatment with MOPP (mustine, vincristine, procarbazine, and prednisolone) or modified MOPP regimens. Neither solid tumours nor ANLL occurred in patients given ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine). The highest incidence of leukaemia (5.4%) occurred after treatment with extensive RT plus (5.4%) occurred after treatment with extensive RT plus MOPP; hence the benefits of this approach in Hodgkin's disease must be weighed against its carcinogenic potential.

Adult↗
PubMed1994

Premorbid diet and the prognosis of women with breast cancer.

BACKGROUND: Consumption of a high-fat diet has been associated with poor survival in breast cancer patients. However, studies examining this association are limited and have not used adjustment of energy in their estimates. PURPOSE: The effect of usual diet before diagnosis of breast cancer on the risk of dying of breast cancer was examined in a cohort of women with breast cancer from the National Breast Screening Study (NBSS) in Canada. METHODS: From a cohort of 89,835 women in the NBSS, a total of 1270 histologically confirmed cases of invasive carcinoma of the breast were identified by active follow-up, supplemented by passive follow-up involving record linkage to provincial cancer registries. Of these, 678 case patients who had completed a diet history and were diagnosed from January 1982 up to June 1992 formed the cohort for this investigation. Diet was ascertained from a self-administered diet-history questionnaire. Mortality data were obtained by linkage to the Canadian Mortality Data Base of Statistics Canada, provincial cancer registries, and annual follow-up of cases through physicians. Risk of dying and survival probabilities were estimated by the Cox proportional hazards method and the actuarial life-table method. RESULTS: There were 83 deaths in this study cohort of 678 women; 76 deaths were due to breast cancer, and the remaining seven resulted from other causes. The 5-year survival rate was 90%. For every 5% increase in energy from saturated fat, the risk of dying of breast cancer increased by 50% (hazard ratio = 1.50; 95% confidence interval [CI]: 1.08-2.08). No significant increase in risk was seen with total fat intake (hazard ratio = 1.21; 95% CI = 0.91-1.61) or oleic acid intake (hazard ratio = 1.25; 95% CI = 0.90-1.74). There was a lower risk of dying of breast cancer in the highest quartiles of beta carotene intake (hazard ratio = 0.48; 95% CI = 0.23-0.99) and vitamin C intake (hazard ratio = 0.43; 95% CI: 0.21-0.86); both vitamins showed a significant dose-response relationship (P for trend, < or = .05). These effects varied with menopausal status at diagnosis and tumor characteristics. CONCLUSIONS: These results suggest an increased risk of dying of breast cancer with higher intakes of saturated fat before diagnosis and slightly reduced risk with higher intakes of beta carotene and vitamin C. IMPLICATIONS: More attention should be paid to premorbid dietary habits in relation to breast cancer prognosis. Further studies, however, need to be done with full ascertainment of dietary changes prior to and subsequent to diagnosis.

Adult↗
PubMed1992

Late relapse and mortality in stage I large bowel cancer.

The outcome was determined for patients with Stage I cancers of the large bowel (colon, rectum, and anus) who were treated from 1982-1989. In 119 consecutive patients, the 5-year survival was approximately 70% (72% by the absolute direct method; 67% by the actuarial life table method). Although the overall 5-year survival was similar to numerous other published reports, it was disturbing to observe that 41% of the living patients had relapsed. Furthermore, although 88/119 (67%) were alive at last report, 2-7 years after treatment, only 23 (19%) were believed to be free of cancer. We conclude that follow-up for more than 5 years and the assessment of disease-free survival are required to evaluate the outcome from Stage I large bowel cancer.

Actuarial Analysis↗
PubMed2000

Use of the intrauterine device: efficacy and safety.

OBJECTIVES: To characterize the family planning center population that used an intrauterine device (IUD), to compare the reasons for its removal and types of incidents encountered by nulliparous women and women with children, and to evaluate the efficacy and safety of this method by the use of life tables. METHOD: This was an observational, descriptive, prospective study of 774 women, recruited over a 5-year period, who used an IUD by informed choice, presented no absolute contraindications and were assessed throughout the whole follow-up period. RESULTS: The mean age (standard deviation) of IUD use was 32.8 (5.9) years for non-nulliparous women and 27.4 (5.3) years for nulliparous women (p < 0.001). Follow-up was completed at the family planning center for 80.1% of women. No differences were observed between nulliparous and non-nulliparous women with respect to accidental pregnancy, suspected pelvic inflammatory disease or expulsion. Non-nulliparous women experienced more major bleeding incidents and anemia (p = 0.010). All pregnancies occurred with low-load devices. Nulliparous women discontinued IUD use more often due to a desire to become pregnant (p = 0.009) and suffered more vulvovaginal infections (p = 0.044). CONCLUSIONS: The IUD is a safe contraceptive option regardless of parity, provided that women are carefully selected.

Adult↗
PubMed1988

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↗
PubMed1999

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↗
PubMed1992

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↗
PubMed1979

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↗
PubMed1997

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↗
PubMed1992

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↗