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PubMed1981

Incidence of hypothyroidism after radioactive iodine therapy for thyrotoxicosis in Hong Kong Chinese.

The incidence of hypothyroidism in 1396 Chinese patients in Hong Kong treated for hyperthyroidism with 131I therapy is presented using the life-table method of analysis. One year after therapy only 6% of patients were hypothyroid, but the subsequent annual incidence was 3.5%, emphasising the need for life-time surveillance of these patients. A higher incidence of subsequent hypothyroidism was found in patients with diffuse surgical treatment, the total dose or number of doses of 131I, the severity of thyrotoxicosis and the age of the patient did not influence the rate of onset of hypothyroidism. The data suggest that in order to minimise the occurrence of hypothyroidism a lower dose of 131I per gram of thyroid mass should be used for patients with small diffuse glands.

Adult↗

PubMed1998

Clinical factors associated with progression of normal-tension glaucoma.

PURPOSE: To investigate clinical factors associated with the progression of visual field loss in normal-tension glaucoma (NTG). METHODS: One hundred and ten patients with NTG whose cases were followed for more than 2 years were retrospectively analyzed with the Kaplan-Meier life table method and the Cox proportional hazards model. Several clinical factors were investigated to find a possible association with progression of glaucomatous visual field defined by two different definitions: one by mean deviation change and the other by pointwise comparison. RESULTS: The Cox proportional hazards model indicated that change in the visual field was significantly associated with treatment with calcium channel blockers, recovery rate from a cold recovery test, systolic blood pressure, disc hemorrhage, corrected pattern standard deviation, mean deviation, and fluctuation of intraocular pressure (IOP) at a 24-hour phasing. The probability of nonprogression of visual field loss was significantly higher for patients taking calcium channel blockers than for control subjects by either definition of visual field progression. CONCLUSION: Factors other than IOP, including the use of calcium channel blockers, are associated with the outcome of visual field loss in NTG.

Adult↗

PubMed2000

Life table analysis of ascariasis in a rural community in Jiangxi Province, China.

The prevalence of ascariasis is very high in parts of rural areas in southern China. The high prevalence of ascariasis is one of the most neglected public health problems. A longitudinal investigation on the prevalence of ascariasis in a rural community in China was reported previously. In this article, we re-analyze the reported age specific prevalence of ascariasis using a life table method. The results from our analysis may provide a better summary of the impact of the disease on the studied population.

Adolescent↗

PubMed1991

The fetal life table revisited: spontaneous abortion rates in three Kaiser Permanente cohorts.

A cohort of 9,055 singleton pregnancies was identified by conventional urine tests or physician examination at the Kaiser Permanente Medical Care Program in Northern California in 1981-1982. Using life table methods, we estimated the cumulative risk of spontaneous abortion or fetal death through the end of pregnancy as 13.0% of all pregnancies surviving 1 week or more past the time of the first missed menses. This value was lower than the estimates of 15.1% and 16.0%, respectively, from two previous fetal life table studies conducted at Kaiser Permanente in prior decades, but similar to estimates from recent, smaller studies of early pregnancy diagnosed by human chorionic gonadotropin. The major difference in survival between the three Kaiser Permanente cohorts was in the earliest gestational week of observation, week 5 from the last menstrual period, where the older data were sparse and potentially biased. High loss rates during this week accounted for one-fourth to one-third of the cumulative risk observed in the older studies. Although the older cohorts were larger, the 1981-1982 cohort included five times and three times as many pregnancies under observation during week 5 from the last menstrual period, yielding more stable estimates for this period. Because of improved reliability of early pregnancy testing and an emphasis on early prenatal care, the mean gestational age at entry to the 1981-1982 cohort was 10.4 weeks from the last menstrual period compared to 14.3 weeks and 13.7 weeks for the older studies. All three studies showed a peak for risk of spontaneous abortion around weeks 10-12 from the last menstrual period.

Abortion, Spontaneous↗

PubMed2001

Mortality and life-years lost due to alcohol: a comparison of acute and chronic causes.

OBJECTIVES: (i) To estimate the numbers of deaths and person-years of life lost (PYLL) due to high-risk alcohol consumption in Australia during 1997, using current estimates of consumption. (ii) To compare the number of deaths and PYLL due to acute conditions associated with bouts of intoxication and chronic conditions associated with long-term misuse of alcohol. METHODS: All Australian deaths during 1997 related to conditions considered to be partially or wholly caused by high-risk alcohol consumption were extracted from the Australian Bureau of Statistics Mortality Datafile and adjusted by alcohol aetiologic fractions calculated for Australia in 1997. A life-table method was used to estimate the PYLL for deaths from alcohol-caused conditions. MAIN OUTCOME MEASURES: Numbers of all deaths and PYLL due to chronic and acute alcohol-related conditions. RESULTS: Of the 3290 estimated alcohol-caused deaths in 1997, chronic conditions (eg, alcoholic liver cirrhosis and alcohol dependence) accounted for 42%, acute conditions (eg, alcohol-related road injuries and assaults) for 28% and mixed (chronic and acute) for 30%. Of the 62914 estimated potential life years lost, acute conditions were responsible for 46%, chronic for 33% and mixed for 21%. The average number of years of life lost through deaths from acute conditions was more than twice that from chronic conditions, because the former mostly involved younger people. CONCLUSIONS: In view of the societal burdens imposed by premature deaths, more effective public health strategies are needed to reduce the harm associated with occasional high-risk drinking (as well as sustained high-risk drinking), especially among young people.

Adolescent↗

PubMed2005

Progression of self-reported symptoms in laboratory animal allergy.

BACKGROUND: Laboratory animal allergy is a common illness among workers exposed to laboratory animals and can progress to symptoms of asthma. OBJECTIVES: This study evaluates the continuum of disease from allergy symptoms to asthma symptoms in a dynamic cohort of workers exposed to animals in a pharmaceutical company. METHODS: Data arose from annual questionnaires administered to workers in a surveillance program established to monitor exposure to animals and the development of allergy. The life-table method was used to compare asthma-free survival between workers with and without symptoms of allergy. A Cox proportional hazards model was used to examine the effects of covariates on the development of asthma. RESULTS: A total of 603 workers contributed 2527.4 person-years to the study over the 12.3-year period. The probabilities of experiencing asthma symptoms by the 11th year of follow-up were 0.367 for workers with allergy symptoms and 0.052 for those without allergy symptoms. The hazard ratio for asthma symptoms when comparing workers with and without allergy symptoms was 7.39 (95% CI, 3.29-16.60) after adjustment for sex and family history of allergy. Female subjects developed asthma at a rate 3.4 times that of male subjects. CONCLUSIONS: This study supports the hypothesis that laboratory animal allergy symptoms are a major risk factor for the development of asthma. It also suggests a heightened risk of asthma for women who work with laboratory animals, a finding that has not been previously reported.

Adolescent↗

PubMed2004

Cycloid psychoses are not part of a bipolar affective spectrum: results of a controlled family study.

BACKGROUND: Whereas a growing body of evidence suggests that cycloid psychoses have to be separated from schizophrenic psychoses, their relations to bipolar affective disorder are less clear. To further clarify this issue a controlled family study was undertaken. METHODS: All living and traceable adult first-degree relatives of 45 cycloid psychotic, 32 manic-depressive and 27 control probands were personally examined by an experienced psychiatrist blind to the diagnosis of the index proband. Data about not traceable relatives were collected by the "Family-History"-Method. A catamnestic diagnosis was established for each of the 431 relatives blind to family data. Age-corrected morbidity risks were calculated using the life-table method. RESULTS: Relatives of cycloid psychotic patients showed a significantly lower morbidity risk for endogenous psychoses in general and manic-depressive illness compared to relatives of patients with manic-depressive illness. The familial morbidity risk for cycloid psychoses was low and did not differ significantly in both proband groups. Relatives of cycloid psychotic patients however did not differ significantly from relatives of controls regarding familial morbidity. LIMITATIONS: Our time-consuming methodical procedure implicated a relatively small number of participants due to restricted personnel resources. The restriction to hospitalised probands could possibly cause a limited representativity of the study sample. CONCLUSIONS: Our results suggest that cycloid psychoses are aetiologically different from manic-depressive illness and could not be integrated into a spectrum of bipolar affective disorders. The findings provide further evidence for a nosological independence of cycloid psychoses.

Adolescent↗

PubMed1984

Seeding human arterial prostheses with mechanically derived endothelium. The detrimental effect of smoking.

Endothelial healing of Dacron arterial prostheses can be hastened in dogs by seeding autogenous venous endothelium onto the prostheses in a single-staged operation. To determine whether this technique enhances the patency of human grafts, we studied the results of 186 operations on 161 patients performed between February 23, 1978, and December 1, 1982. Alternately allocating patients to treatment with seeded and unseeded Dacron knitted prostheses, we performed axillary-femoral and axillary-femoral-femoral bypasses in 11 patients (six seeded and five unseeded) and femoral-femoral bypasses in 28 (13 seeded and 15 unseeded). By a randomized block method of treatment allocation, femoral-popliteal grafts were installed in 147 limbs (112 vein, 18 seeded, and 17 unseeded). Patency was analyzed by the life-table method. Overall, femoral-femoral and femoral-popliteal bypasses demonstrated no difference between the seeded and unseeded grafts. Patency was somewhat better in seeded than unseeded axillary-femoral bypasses. Nevertheless, nonsmokers with seeded femoral-popliteal Dacron grafts enjoyed a significantly better graft patency than those with unseeded grafts (p = 0.035), whereas a substantial deterioration of seeded Dacron grafts was observed in those patients who smoked (p = 0.008 at 6 months). Vein grafts performed better than either seeded or unseeded Dacron prostheses (p = 0.016). Serum beta-thromboglobulin (BTG) levels varied widely and did not differ among any of the treatment groups. We concluded that endothelial seeding improved the patency of human arterial prostheses but that results were worse if the patient was a smoker. BTG was not a useful measure of the platelet activation induced by an arterial prosthesis.

Blood Coagulation Disorders↗

PubMed2001

[Thymoma-report of 166 patients].

OBJECTIVE: To discuss the characteristics of operation and the prognosis of 166 patients with thymoma. METHODS: 166 thymoma patients were treated from February 1985 to February 2000. By Masaoka staging system, there were 102 (61.4%) stage I, 28 (16.9%) stage II, 24 (14.5%) stage III, 12 (7.2%) stage IV a and 0 stage IV b lesions. The relation between stage and survival rate was analyzed. RESULTS: One (0.6%) patient died of the operation. 137 (82.5%) patients underwent radical operation. Thirty patients were lost to follow-up. With the life table method, the 10-year survival rate was 56.8%, with 79.8% for stage I, 51.6% for stage II, 33.5% for stage III and 0% for stage IV patients. CONCLUSION: Diagnosis of thymoma still depends on both clinical and pathological findings, which are correlated with stage. The principal treatment is to resect the tumor as completely as possible so as to relieve the symptoms and prolong the life of the patient.

Adult↗

PubMed2000

Benign ovarian cysts and ovarian cancer: a cohort study with implications for screening.

BACKGROUND: Whether some benign ovarian cysts can develop into cancerous cysts is not known. If a large proportion of ovarian cancers arose in this way, it might be possible to remove the benign cysts in a screening programme before they became malignant. We used follow-up data from a cohort of 5479 self-referred women without symptoms, who participated in a ultrasonographic-screening trial for early ovarian cancer between June, 1981, and August, 1987. We assessed whether the removal of persistent ovarian cysts from these women was associated with a reduction in the expected number of deaths from ovarian cancer in the cohort as a whole. METHODS: The expected number of deaths from all causes, all cancers, and ovarian, breast, and colorectal cancers were calculated for the study cohort by the standard life-table method. The actual number of deaths and each cause were obtained and the proportional mortality ratio was calculated for each cause of death. FINDINGS: 5135 (95%) of the participants in the original trial were traced. During the screening, five of these women were found to have stage I epithelial ovarian cancer and 88 had benign epithelial ovarian tumours. The number of reported deaths from all causes (387 [50% of expected]), all cancers (221 [71%]), and ovarian cancer (22 [90%]) was lower than expected because of the "healthy-volunteer effect". Proportional mortality ratios were 100% (by definition) for all cancers, 141% for breast cancer, 128% for ovarian cancer (95% CI 87.7-187.6, p=0.19), 84% for colorectal cancer, and 48% for lung cancer. INTERPRETATION: The removal of persistent ovarian cysts was not associated with a decrease in the proportion of expected deaths from ovarian cancer relative to other cancers during follow-up. For population-based screening of healthy women without a family history of ovarian cancer, a screening test is required that is specific and sensitive to early malignant disease, and inexpensive.

Adult↗

PubMed2003

Uveal melanoma survival in Sweden from 1960 to 1998.

PURPOSE: To investigate the crude and relative survival rates in patients with uveal melanoma in Sweden during the period from 1960 to 1998. METHODS: A population-based national survey revealed 2997 cases of uveal melanoma in the Swedish Cancer Registry. The survival rates were calculated by the Hakulinen life-table method, using relative survival as an estimate for deaths due to uveal melanoma. The excess mortality rates were calculated with confidence intervals for the first 15 years after diagnosis. Multivariate regression analysis was undertaken to evaluate the influence of gender, age, and calendar period on relative survival the first 5 years after diagnosis. The underlying causes of deaths in the patients with uveal melanoma, as found in the Cause of Death Registry were also investigated. RESULTS: Up to December 31, 1998, 2003 patients had died. The 5-year crude survival rate was 60.3% and the relative survival 70.1%. After 10 years, the rates were 42.5% and 59.4%, respectively. Significant excess mortality existed up to 5.5 years after diagnosis. In the multivariate model, younger age (P < 0.001) and later calendar period (P = 0.002), but not gender (P = 0.117), were associated with better relative survival. Deaths due to uveal melanoma were misclassified in the Cause of Death Registry in more than half of the cases. CONCLUSIONS: This study, covering more than 95% of the uveal melanoma cases in the Swedish population revealed an improvement in relative survival rates for patients with uveal melanoma over time and a significant excess mortality up to 5.5 years after diagnosis.

Adolescent↗

PubMed2004

[Analysis of long-term prognostic factors of epithelial ovarian cancer].

BACKGROUND & OBJECTIVE: Because most of patients with ovarian cancer are in advanced stage when initially noted, and are prone to relapse, ovarian cancer is a tough disease to treat. This study was to determine long-term prognostic factors correlated with prolonged survival of epithelial ovarian cancer patients, give reference for clinical practice. METHODS: Records of 691 patients with epithelial ovarian cancer, admitted in our hospital from Jan. 1986 to Dec. 2000, were retrospectively analyzed. Survival rate was calculated by life table method, and relevant factors were evaluated by univariate analysis. The potential prognostic variables were studied by Cox regression model. RESULTS: The 5-year, and 10-year survival rates of all patients were 56.0%, and 44.6%. Cox regression model revealed that clinical stage, size of tumor residues, pathologic type, histological grade, and number of chemotherapy cycles after surgery emerged as independent prognostic factors. CONCLUSION: Accurate clinical staging and histopathologic assessment, satisfactory cytoreduction, and effective adequate chemotherapy may affect prognosis of ovarian cancer patients.

Adolescent↗

PubMed2005

[Multivariate prognostic analysis in gastric carcinoma patients after radical operation].

BACKGROUND & OBJECTIVE: Whether received radical operation is an important prognostic factor of gastric carcinoma. But the long-term efficacies of radical operation on different patients are not the same. This study was to investigate prognostic factors of gastric carcinoma. METHODS: Clinical data of 405 patients with gastric carcinoma, received radical operation from Jan. 1985 to Dec. 1995 in Cancer Center of Sun Yat-sen University, were analyzed retrospectively. Life table method was used to analyze survival rate, Wilcoxon test was used for statistical comparison, and Cox regression model was used for multivariate analysis. RESULTS: The 5-year overall survival rate was 43.4%. The 5-year survival rates of patients in pathologic TNM (pTNM) stage I, II, III, and IV were 75.6%, 58.7%, 28.0%, and 18.4%, respectively (P < 0.01). The 5- year survival rates of patients with tumor sizes of less than 2.0 cm, 2.0-3.9 cm, 4.0-5.9 cm, 6.0-7.9 cm, and no less than 8.0 cm were 82.0%, 57.4%, 43.7%, 38.7%, and 26.9%, respectively (P < 0.05). In addition, the 5-year survival rate was higher in patients with perioperative chemotherapy than in patients without perioperative chemotherapy (47.2% vs. 37.8%, P < 0.05). Univariate analysis showed that perioperative chemotherapy, Borrmann type, tumor size, pathologic type, and pTNM stage were prognostic factors of gastric carcinoma. Multivariate analysis showed that pTNM stage, tumor size, and perioperative chemotherapy were independent prognostic factors of gastric carcinoma. CONCLUSIONS: pTNM stage, tumor size, and perioperative chemotherapy are the most significant factors influencing prognosis of gastric carcinoma patients after radical operation. Perioperative chemotherapy contributes to enhance survival rate of gastric carcinoma patients.

Adenocarcinoma↗

PubMedDate not supplied

Computing population-based estimates of health-adjusted life expectancy.

Observed health-adjusted life expectancy (HALE) is an indicator of population health. There are a number of ways to compute HALE for a community. The authors surveyed several methods and demonstrate resulting variation in the estimates of HALE. Quality of well-being (QWB) measures from 1,430 participants in the Beaver Dam Health Outcomes Study are taken as weights. Actuarial life-table methods using community mortality data, State of Wisconsin census data from two time frames, and U.S. census data are used with the QWB to estimate HALE. Measurement of community population health using HALE computations can be completed with national, regional, or local data. Community-level estimates may not be well approximated using large-scale mortality experience. A Bayesian method is developed combining the local data with regional data. The Bayesian method creates a smooth set of rates, retains the local flavor of the community, and gives a measure of variability of the estimated HALE.

Actuarial Analysis↗

PubMed1994

Axillofemoral grafting with externally supported polytetrafluoroethylene.

OBJECTIVE: To evaluate the results of axillofemoral bypass grafting using externally supported polytetrafluoroethylene. DESIGN: Consecutive patients who were operated on by us from 1983 to the present were prospectively followed up in a vascular registry. The results of surgery with respect to morbidity and mortality, patency, limb salvage, and patient survival were determined by life-table methods. PATIENTS: A standardized operative technique was used to perform 184 axillofemoral bypass procedures in 164 consecutive patients (age range, 14 to 90 years; mean age, 67 years; female, 33%). Follow-up ranged from 0 to 95 months (mean, 23 months). RESULTS: Ischemia was the indication for 83% of the procedures, and aortic sepsis was the indication for 16%. There were nine operative deaths (5%) and 17 major complications. Life-table primary patency, limb salvage, and survival rates at 5 years were 71%, 92%, and 52%, respectively. Indication for surgery, patency of the superficial femoral artery, and the performance of multilevel procedures did not significantly influence patency. CONCLUSIONS: The results of axillofemoral grafting using polytetrafluoroethylene are equivalent to those achieved with other accepted methods of treatment for lower extremity ischemia, including balloon angioplasty, aortofemoral bypass, and infrainguinal bypass. Axillofemoral bypass is an appropriate technique that is deserving of more widespread use.

Adolescent↗

PubMed2003

Survival analysis is a better estimate of recurrent disc herniation.

Studies on recurrent disc herniation quote rates of recurrence without regard to the times of recurrence and the influence of longer follow-up. Our objective was to assess the use of survival analysis to measure the rate of revision after lumbar microdiscectomy. We undertook a retrospective analysis of the hospital records of 993 patients who underwent lumbar microdiscectomy over a period of ten years. After calculating the overall rate of revision for the mean length of follow-up, we carried out a survival analysis using the life-table method. During the study period 49 patients had a revision microdiscectomy. This gave an overall rate of revision of 4.9% at a mean follow-up of 5.25 years. Using survival analysis, the rate of revision was 7.9% at a follow-up of ten years when the number at risk was 84. Survival analysis gives a more accurate estimation of the true rate of recurrence for patients undergoing lumbar microdiscectomy. The method allows better comparison between different interventions for disc herniation.

Adult↗

PubMed2000

Sex differences in the prevalence of mobility disability in old age: the dynamics of incidence, recovery, and mortality.

OBJECTIVES: This study examined sex differences in the prevalence of mobility disability in older adults according to the influences of three components of prevalence: disability incidence, recovery from disability, and mortality. METHODS: Participants in a population-based study of older adults from three communities in the United States (N = 10,263) were studied for up to 7 years. Life table methods were used to estimate the influence of each of the three components of disability prevalence in women and men. Sex differences in probabilities for transition states were measured by relative risks derived from a single model using a Markov chain approach. RESULTS: The proportion of disabled women increased from 22% of women aged 70 years to 81% of those aged 90 years. In men, comparable figures were 15% and 57%. Incidence had the greatest impact on the sex differences in disability prevalence until age 90 and older when recovery rates had a greater impact on differences in prevalence. Mortality differences in men and women had only a modest impact on sex differences in disability prevalence. These findings initially seemed to contradict striking sex differences observed in the relative risks for mortality in men compared with women. Subsequent graphical analyses showed that incidence rather than recovery or mortality largely accounted for sex differences in disability prevalence in old age. CONCLUSION: Disability incidence, recovery from disability, and mortality dynamically influence the sex differences in the prevalence of mobility disability. However, incidence has the greatest impact overall on the higher prevalence of disability in women compared with men.

Adult↗

PubMed1999

The effect of long, slow haemodialysis on patient survival.

BACKGROUND: Long, slow haemodialysis (24 h/week) has been associated with excellent patient survival and reduced cardiovascular mortality. Comparisons of patient survival have only been possible with registry data and other published series which do not control for individual patient characteristics. This retrospective study compares actuarial patient survival between a unit using long, slow haemodialysis (Tassin) and one employing 'conventional' haemodialysis (Nottingham). METHODS: All patients undergoing haemodialysis at each centre since 1980 were included (Tassin, 452 patients; Nottingham, 282 patients). Actuarial curves of patient survival were calculated by the life-table method and log rank test was used to compare data. Patients were grouped as follows: standard (SRD) and non-standard (NSRD) renal diseases; diabetics and non-diabetics; patients with and without cardiovascular antecedents; risk stratification based on age and comorbidity. RESULTS: Overall survival was significantly better in Tassin. This difference was also noted for patients with SRD and non-diabetics (both P < 0.001) and for those with (P = 0.007) and without (P < 0.001) cardiovascular antecedents. Survival did not differ significantly for NSRD and diabetics. Survival was better in Tassin in low-risk (P < 0.001) and medium-risk (P < 0.001) groups, but not for high-risk (risk stratification). CONCLUSIONS: Overall survival is increased on long, slow haemodialysis. Although the benefits are seen in the most favourable prognostic categories, they are also present in patients with comorbid illness (medium-risk group) and pre-existing cardiovascular disease.

Adolescent↗