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PubMed1995

Active life expectancy among elderly Japanese.

BACKGROUND: This study estimated the active life expectancy (ALE) among the elderly in a Japanese urban society to determine whether or not the Japanese live long lives at the expense of life quality. METHODS: Survival and ability to perform activities of daily living (ADLs) were followed up on a probability sample (n = 3,459) of the aged people living in Sendai City, Japan, between 1988 and 1991. ALE was calculated by an increment-decrement life table method. RESULTS: At age 65, ALE was 14.7 years for men and 17.7 years for women. The duration of active life occupied 91% of the total life expectancy for men and 87% for women. These values were further compared with those reported for the elderly in the United States. ALE among the Japanese subjects was longer than that among the American elderly. The percentage of remaining life that was active was comparable with that in the United States. However, the interpretation of the results requires caution because of the difficulty in comparing self-reported disabilities across cultures. CONCLUSION: The authors conclude that it is premature at this time to judge which country is better in terms of functional status among the elderly. An international comparison of ALE would create an opportunity to evaluate and promote health and function of the elderly population worldwide. For this purpose, an international standardization of ALE measurement is urgently needed.

Activities of Daily Living↗

PubMed1997

Analysis of late stomal complications following ostomy surgery.

BACKGROUND AND AIMS: This study was aimed to evaluate the late complications of ostomy surgery in a strictly followed patient population of a university hospital. MATERIAL AND METHODS: An actuarial analysis of the complications of 156 patients with permanent ostomies using the life-table method was performed. RESULTS: The crude and actuarial risks of late stomal complications in 156 patients after a mean follow-up of 8 years were 39 per cent and 59 per cent. The cumulative risk of complications did not differ between the stoma types. Paracolostomy hernia was the most common complication of the colostomy, 27 per cent, retraction of ileostomy, 24 per cent, and intestinal obstruction of urostomy, 28 per cent. Mesenteric fixation was here associated with a lower chance of prolapse (P < 0.025), but the closure of lateral space did not reduce the risk of intestinal obstruction. Skin irritation was more common after a creation of ileostomy than after other stoma creations (P < 0.001). The revisional surgery rate was lower following colostomy than following other stoma formations (P < 0.034). Adaptation to the stoma had occurred in 74% of the patients, but 8 per cent of the patients had intractable symptoms at the time of the analysis. CONCLUSION: Ostomy surgery involves a high rate of late complications and there is a small but important subgroup of patients whose quality of life is seriously affected.

Colostomy↗

PubMed1996

Radiation related complications after ruthenium plaque radiotherapy of uveal melanoma.

AIMS/BACKGROUND: To analyse radiation related complications and secondary enucleation after irradiation of malignant uveal melanoma with ruthenium-106 plaques. METHODS: A series of 100 consecutive eyes irradiated in 1981-91 was analysed using the life table method and the Cox proportional hazards model. The median apical and scleral tumour dose was 100 Gy (range 15-200 Gy) and 1000 Gy (range 200-1200 Gy), respectively. The median follow up time was 2.8 and 2.0 years (range 1 month to 10 years) for anterior and posterior segment complications, respectively. RESULTS: The 3 and 5 year probabilities of being without radiation cataract were 73% and 63%, without neovascular glaucoma 91% and 81%, without vitreous haemorrhage 83% and 74%, without radiation maculopathy 85% and 70%, and without radiation optic neuropathy 90% and 88%, respectively. The risk of radiation cataract was highest with large tumour size (T1 + T2 v T3, p = 0.0027; height < or = 5 v > 5 mm, p = 0.029; largest basal diameter (LBD) < or = 15 v > 15 mm, p < 0.0001) and location of anterior tumour margin anterior v posterior to the equator (p = 0.0003); the risk of neovascular glaucoma with large size (T1 + T2 v T3, p = 0.039; LBD < or = 15 mm v 15 mm, p = 0.021); and the risk of maculopathy and optic neuropathy with proximity of the posterior tumour margin to the fovea and the optic disc (< or = 1.5 v > 1.5 mm; p = 0.030 and p = 0.0004, respectively). In Cox's multivariate analysis the strongest risk indicator for radiation cataract (RR 1.5, 95% CI 1.4-1.6) and vitreous haemorrhage (RR 1.6, 95% CI 1.4-1.8) was the height of the tumour; for neovascular glaucoma the TNM class (RR 6.2, 95% CI 2.7-13.8); for radiation maculopathy location of posterior tumour margin within 2 mm from the fovea (RR 3.4, 95% CI 2.0-6.0); and for radiation optic neuropathy location of tumour margin within 1 DD of the optic disc (RR 6.1, 95% CI 3.0-12.4). The 3 and 5 year probabilities of avoiding enucleation were 92% and 85%, respectively. Ten eyes were enucleated--six because of recurrent tumour growth, three because of treatment complications, and one because of mistakenly suspected extraocular growth. CONCLUSION: The results suggest that the frequency of radiation related complications after ruthenium brachytherapy of uveal melanoma is acceptable, in particular as regard irradiation of small and medium sized tumours for which ruthenium therapy generally is recommended.

Adult↗

PubMed1987

Tubal anastomosis: pregnancy success following reversal of Falope ring or monopolar cautery sterilization.

The present study reviews pregnancy outcome following tubal anastomosis in 80 previously sterilized women. Thirty of 58 women (52%) sterilized by monopolar cautery techniques delivered a living child as compared to 19 of 22 women (86%) sterilized using the Falope ring method. Cumulative pregnancy curves were calculated for the Falope ring and cautery groups using life-table methods. Following reversal of Falope ring sterilization, the estimated cumulative probability of pregnancy 6, 12, 24, and 36 months after surgery was 28.4%, 48.8%, 69.3%, and 87.2% respectively. The corresponding estimates following reversal of cautery sterilization were lower at 6, 12, 24, and 36 months following surgery: 22.7%, 37.8%, 52.4%, and 57.9%, respectively. The ectopic tubal pregnancy and spontaneous abortion rate were higher among women sterilized with monopolar cautery. A decreased pregnancy rate was associated with ampullary-isthmic anastomosis in the cautery group; however, pregnancy was least likely to occur in women with shortened oviducts of less than 4 cm.

Actuarial Analysis↗

PubMed1998

[Surgical treatment results for carcinoma of the gastric cardia in 1832 cases].

OBJECTIVE: To evaluate the results of surgical treatment for carcinoma of the gastric cardia and the prognostic factors. METHODS: The prognostic factors were assessed with 5-year survival rates which was estimated using life table method in 1832 cases. The difference between groups was assessed by the log rank test. RESULTS: The overall resection rate was 76.3% and the radical resection rate 53.4%. The overall 5-year survival rate was 23.5% while in patients treated with curative resection it was 29.9%. The 5-year survival rate was 29.4% in patients received preoperative radiation and 21.5% in patients treated with surgery alone (P > 0.05). Patients whose upper margin of resection was longer than 5 cm away from the tumor had higher 5-year survival rate (25.8%) than those with margin of resection less than 5 cm (18.4%). The difference was statistically significant (P < 0.05). CONCLUSION: Preoperative radiation can increase the survival rate, but it was not statistically significant. Increasing the margin of resection to > 5 cm can improve survival.

Adenocarcinoma↗

PubMed1999

Health deficiencies in Cape Breton County, Nova Scotia, Canada, 1950-1995.

Cape Breton County contains one of the most polluted areas in North America and is socioeconomically depressed. We evaluated mortality patterns in this area over the past 5 decades, focusing on life expectancy and life loss. Life loss refers to the difference in life expectancy of Cape Breton County residents and all Canadians, and was further broken down into disease-specific components using cause-eliminated life table methods. We observed lags in health of 20 to 25 years for residents of Cape Breton County. Life expectancy in some municipalities of Cape Breton County is reduced by more than 5 years. Life loss for these residents is greater than that of any single cause of death for Canadians. Life loss among Cape Breton County women is primarily attributable to cancer, and, among men, to cardiovascular diseases. Life loss from cancer is higher in the steel-producing communities; whereas life loss from respiratory diseases and lung cancer is higher in the coal mining communities. These (and other) decompositions of life loss disclose patterns in health deficiencies that give rise to etiologic hypotheses and provide clues and directions for prevention and interventions.

Adolescent↗

PubMed1995

Autologous saphenous vein popliteal-tibial artery bypass for limb-threatening ischemia: a reassessment.

BACKGROUND: The purpose of this review was to ascertain the cumulative primary and secondary graft patency rates, the cumulative limb salvage rate, and the frequency of atherosclerotic disease progression proximal to the graft origin, in patients with autologous saphenous vein popliteal-tibial artery bypass grafts whose operative indication was limb-threatening ischemia. PATIENTS AND METHODS: Forty-three short autologous saphenous vein grafts originating from the popliteal artery were retrospectively reviewed. The life-table method was used to determine primary and secondary graft patency and limb salvage rates. Atherosclerotic disease progression proximal to the graft origin was assessed via follow-up arteriography, segmental limb pressures, or pulse-volume recordings. All other data were compared by chi-square analysis. RESULTS: The cumulative primary graft patency rate at 1, 3, and 5 years (86%, 66%, 58%) was similar to the cumulative secondary patency rate (90%, 70%, 62%) and the cumulative limb salvage rate (80%, 55%, 55%). No patient developed hemo-dynamically significant atherosclerotic disease proximal to the graft origin during the follow-up period. CONCLUSIONS: The similarity of the life-table data suggests graft-dependent, poorly collateralized limbs; it is therefore not uncommon for these patients to require major amputations shortly after bypass failure. There was no evidence of critical proximal disease progression that might warrant a more proximal graft origin. Poplitealtibial artery bypass grafts are durable, with acceptable graft patency and limb salvage rates.

Adult↗

PubMed2005

Semi-parametric and non-parametric methods for clinical trials with incomplete data.

Last observation carried forward (LOCF) and analysis using only data from subjects who complete a trial (Completers) are commonly used techniques for analysing data in clinical trials with incomplete data when the endpoint is change from baseline at last scheduled visit. We propose two alternative methods. The semi-parametric method, which cumulates changes observed between consecutive time points, is conceptually similar to the familiar life-table method and corresponding Kaplan-Meier estimation when the primary endpoint is time to event. A non-parametric analogue of LOCF is obtained by carrying forward, not the observed value, but the rank of the change from baseline at the last observation for each subject. We refer to this method as the LRCF method. Both procedures retain the simplicity of LOCF and Completers analyses and, like these methods, do not require data imputation or modelling assumptions. In the absence of any incomplete data they reduce to the usual two-sample tests. In simulations intended to reflect chronic diseases that one might encounter in practice, LOCF was observed to produce markedly biased estimates and markedly inflated type I error rates when censoring was unequal in the two treatment arms. These problems did not arise with the Completers, Cumulative Change, or LRCF methods. Cumulative Change and LRCF were more powerful than Completers, and the Cumulative Change test provided more efficient estimates than the Completers analysis, in all simulations. We conclude that the Cumulative Change and LRCF methods are preferable to LOCF and Completers analyses. Mixed model repeated measures (MMRM) performed similarly to Cumulative Change and LRCF and makes somewhat less restrictive assumptions about missingness mechanisms, so that it is also a reasonable alternative to LOCF and Completers analyses.

Alzheimer Disease↗

PubMed1989

Analyses of group sequential clinical trials.

In the first part of this article the methodology of group sequential plans is reviewed. After introducing the basic definition of such plans the main properties are shown. At the end of this section three different plans (Pocock, O'Brien-Fleming, Koepcke) are compared. In the second part of the article some unresolved issues and recent developments in the application of group sequential methods to long-term controlled clinical trials are discussed. These include deviation from the assumptions, life table methods, multiple-arm clinical trials, multiple outcome measures, and confidence intervals.

Actuarial Analysis↗

PubMed1996

The survival analyses of 2738 patients with simple pneumoconiosis.

OBJECTIVES: To explore whether the inhalation of coal mine dust increases the risk of premature death in miners, a survival analysis was conducted in a cohort of 2738 patients with simple pneumoconiosis in the Huai-Bei coal mine, in China. METHODS: Age specific mortalities were calculated by disease severity in terms of pneumoconiotic category with the life table method. The progressions from simple pneumoconiosis to death or progressive massive fibrosis (PMF) were analysed with the Cox's regression model with time as the dependent variable to identify risk factors. RESULTS: During a follow up period (mean 8 y) 3.2% of patients with simple pneumoconiosis developed PMF. The patients with development of PMF presented higher age specific mortalities than those remaining in a state of simple pneumoconiosis (SMR: 3.42; P < 0.01). After adjustment for tuberculosis and duration of work, the relative risk of premature death due to development of PMF was 2.4. Tuberculosis was found to be a main risk factor which not only facilitated premature death (relative risk (RR): 2.0; P < 0.01), but was also a strong facilitator for development of PMF (RR: 7.0; P < 0.01). Also, a long term of work underground and drilling as a main job were identified as risk factors for development of PMF. CONCLUSION: The results imply that patients with simple pneumoconiosis will have altered survival, and premature death among them is related to an increased risk of the development of PMF and the complication of tuberculosis.

Adult↗

PubMedDate not supplied

A multistate analysis of active life expectancy.

With today's lower mortality rates, longer expectations of life, and new medical technologies, the nation's health policy focus has shifted from emphasis on individual survival to emphasis on personal health and independent living. Using longitudinal data sets and new methodological techniques, researchers have begun to assess active life expectancies, estimating not only how long a subpopulation can expect to live beyond each age, but what fractions of the expected remaining lifetime will be lived as independent, dependent, or institutionalized. New ideas are addressed, applying recently developed multistate life table methods to Waves One and Two of the Massachusetts Health Care Panel Study. Expectations of active life are presented for those 65 and older who initially are in one of two functional states of well-being. Included are expectations of life, for those, for example, who were independent and remained so, or those who were dependent and became independent. Although public health officials are concerned about the number of elderly who cease being independent, preliminary analysis shows that a significant number of the dependent elderly regain their independence, a situation which needs to be addressed in health care planning.

Activities of Daily Living↗

PubMed1996

Renovascular hypertension resulting from nonspecific aortoarteritis in children: midterm results of percutaneous transluminal renal angioplasty and predictors of restenosis.

OBJECTIVE: Nonspecific aortoarteritis is a major cause of renovascular hypertension in children. Stenosis of the renal artery is usually long and begins at the origin of that artery. We retrospectively studied the midterm results of angioplasty during treatment and defined the predictors of restenosis in 40 stenoses in 24 children. MATERIALS AND METHODS: All patients had clinically inactive disease and hemodynamically significant stenosis causing hypertension. Midterm results were analyzed by the life table method. The effect of clinical, angiographic, and technical factors on the restenosis rate was tested by the Kaplan-Meir survival method. RESULTS: Technical success was obtained without complications in 38 (95%) of the lesions in 22 (92%) of the patients. The stenosis decreased from 89 +/- 7% to 11 +/- 12%, the pressure gradient fell from 97 +/- 27 to 10 +/- 10 mm Hg, and blood pressure decreased from 174 +/- 14/112 +/- 11 to 141 +/- 13/88 +/- 11 mm Hg (p < .001). Clinical benefit was seen in all patients with technically successful angioplasty. During the follow-up period (33 +/- 22 months), restenosis was seen in eight lesions (20%). The predicted cumulative patency rate at 5 years was 71%. Adverse effects on the rate of restenosis were associated with male sex (p = .04), stenosis beginning at the origin of the renal artery (p = .01), and more than 20% residual stenosis after angioplasty (p = .02). CONCLUSION: Our results show that hypertension in children with renal artery stenosis caused by nonspecific aortoateritis can be safely treated by renal angioplasty with excellent midterm results. A long stenosis beginning at the origin of the artery predisposes to restenosis, but repeat dilatation often produces lasting benefit.

Adolescent↗

PubMed1997

A prospective comparison of two expanded polytetrafluoroethylene grafts for linear forearm hemodialysis access: does the manufacturer matter?

BACKGROUND: The function and patency of standard 6-mm Goretex (W.L. Gore and Associates, Flagstaff, AZ) and Impra (Impra, Inc., Tempe, AZ) expanded polytetrafluoroethylene (e-PTFE) grafts for hemodialysis as radial-antecubital linear arteriovenous fistulae for dialysis are compared. STUDY DESIGN: A randomized clinical trial was conducted in two community dialysis centers and in one hospital-based center serviced by one vascular surgical practice, that performed the access surgery. Selection of linear forearm access, as opposed to other hemodialysis graft configurations, was at the discretion of the surgeon. Candidates for linear grafts had palpable radial pulses with a normal Allen test and normal digital Doppler flow in the hand. Linear grafts were placed using end-to-side anastomoses to the artery and vein, and the graft type was determined by randomization. Primary patency was determined by first episode of thrombosis, first revision, or angioplasty of the graft. Secondary patency after thrombectomy, revision, or angioplasty was determined when the graft was no longer clinically usable, and a new graft needed to be placed as a parallel conduit in the forearm or in another site. Statistical analysis was by actuarial life-table methods. RESULTS: There were 131 linear forearm grafts in 117 patients. The Impra and Goretex groups were equally matched for gender and major risk factors, except for smoking, which was more common in the Goretex group. Minimum followup was 24 months. Life table primary patencies at 1 year (Impra 43%, Goretex 47%) and at 2 years (Impra 30%, Goretex 26%) were not statistically different (p = 0.78); secondary patency was also equal at 1 year (Impra 49%, Goretex 69%) and at 2 years (Impra 33%, Goretex 41%) (p = 0.15). Discontinuance of use of a patent graft, complications, episodes of thrombosis, and the need to replace the original graft occurred in the two groups without a statistically significant difference. CONCLUSIONS: In the linear forearm position from the radial artery to an antecubital vein, there is no difference in the performance of 6-mm standard e-PTFE grafts on the basis of manufacturer, whether Goretex or Impra. On the basis of performance, linear forearm dialysis grafts are an acceptable method for hemodialysis access.

Adult↗

PubMed1989

Using survival methods to estimate age-at-onset distributions for genetic diseases with an application to Huntington disease.

Two important considerations in genetic disease are the risk of inheriting the gene for a disease and the age-at-onset distribution among those inheriting it. This paper describes the use of survival data analytic methods to estimate these entities. When a sample consists of children and/or siblings of affected individuals, standard life-table methods such as Kaplan-Meier techniques can be applied. The desired estimators are functions of the Kaplan-Meier estimator and their properties are derived using the invariance principle and delta methods. A discussion of the underlying assumptions and estimators of standard errors and mean onset age are given. In an application to Huntington disease, the risk (+/- SE) of inheriting the gene for disease among children of a singly affected parent is estimated to be 0.499 +/- 0.020 and the estimated mean onset age (+/- SE) is 45.6 +/- 0.7.

Actuarial Analysis↗

PubMed2004

A new method for correcting under-estimation of disabled life expectancy and an application to the Chinese oldest-old.

This article demonstrates that disabled life expectancies that are based on conventional multistate life-table methods are significantly underestimated because of the assumption of no changes in functional status between age x and death. We present a new method to correct the bias and apply it to data from a longitudinal survey of about 9,000 oldest-old Chinese aged 80-105 collected in 1998 and 2000. In our application, the age trajectories of disability (activities of daily living--ADL), status-specific death rates, and the probabilities of transitions between ADL states of the oldest-old were investigated for the first time in a developing country. In this article, we report estimates of bias-corrected disabled and active life expectancies of the Chinese oldest-old and demonstrate patterns of large differences associated with initial status, gender, and advances in ages. Using combined information on ADL disabilities and length of having been bedridden before dying, we analyze gender and age patterns of the extent of morbidity before dying among the oldest-old and their implications for debates on the hypothesis of compression of morbidity.

Activities of Daily Living↗

PubMed1993

Risk of another basal cell carcinoma developing after treatment of a basal cell carcinoma.

BACKGROUND: There is an increased risk of new basal cell carcinomas (BCCs) developing in a person who has had a BCC. OBJECTIVE: This study attempts to define the magnitude of this increased risk. METHODS: The charts of 260 white patients with a histologically proven BCC were reviewed for the occurrence of new BCCs. The cumulative 5-year incidence (modified life-table method) for new BCCs developing in these patients was compared with the 5-year incidence in the general white population of the United States. RESULTS: Of the 260 patients, new BCCs developed in 137 within an average of 38.3 months, a 5-year cumulative rate of one or more new BCCs of 45.2%. The yearly risk for new BCCs developing in the study population remained high during the 5-year interval. In the general white population of the United States, the maximal 5-year incidence was calculated to be 5% (p < 0.005, chi-square test). CONCLUSION: Patients with a history of BCC require life-long follow-up because of the high probability of new BCCs developing.

Aged↗

PubMed2003

Smoking expands expected lifetime with musculoskeletal disease.

By indirect estimation of mortality from smoking and life table methods we estimated expected lifetime without musculoskeletal diseases among never smokers, ex-smokers, and smokers. We found that although life expectancy of a heavy smoker is 7 years shorter than that of a never smoker, heavy smokers can expect to live more than 2 years longer with musculoskeletal diseases than never smokers.

Comorbidity↗

PubMed2003

Estimating mean lifetime.

The life expectancy implied by current age-specific mortality rates is calculated with life table methods that are among the oldest and most fundamental tools of demography. We demonstrate that these conventional estimates of period life expectancy are affected by an undesirable "tempo effect." The tempo effect is positive when the mean age at death is rising and negative when the mean is declining. Estimates of the effect for females in three countries with high and rising life expectancy range from 1.6 yr in the U.S. and Sweden to 2.4 yr in France for the period 1980-1995.

Age Factors↗