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OBJECTIVES: To develop a classification tree for predicting the risk of recurrent falling in community-dwelling older persons using tree-structured survival analysis (TSSA). DESIGN: A prospective cohort study. SETTING: A community in the Netherlands. PARTICIPANTS: One thousand three hundred sixty-five community-dwelling older persons (>/=65) from the Longitudinal Aging Study Amsterdam (LASA). MEASUREMENTS: In 1995, physical, cognitive, emotional, and social aspects of functioning were assessed. Subsequently, a prospective fall follow-up, specifically on recurrent falls (two falls within 6 months) was conducted for 3 years. RESULTS: The classification tree included 11 end groups differing in risk of recurrent falling based on a minimum of two and a maximum of six predictors. The first split in the tree involved two or more falls versus fewer than two falls in the year preceding the interview. Respondents with two or more falls in the year preceding the interview (n=193) and with at least two functional limitations (n=98) had a 75% risk of becoming a recurrent faller, whereas respondents with fewer than two functional limitations were further divided into a group with regular dizziness (n=11, risk of 68%) and a group with no regular dizziness (n=84, risk of 30%). In respondents with fewer than two falls in the year preceding the interview (n=1,172), the risk of becoming a recurrent faller varied between 9% and 70%. Predictors in this branch of the tree were low performance, low handgrip strength, alcohol use, pain, high level of education, and high level of physical activity. CONCLUSION: This classification tree included 11 end groups differing in the risk of recurrent falling based on specific combinations of a maximum of six easily measurable predictors. The classification tree can identify subjects who are eligible for preventive measures in public health strategies.  相似文献   
23.
OBJECTIVES. This study examines the association of hearing impairment and chronic diseases (diabetes mellitus, lung disease, cardiac disease, stroke, cancer, peripheral artery disease, osteoarthritis, rheumatoid arthritis) with psychosocial status (depression, self-efficacy, mastery, loneliness, social network size) in older persons. METHODS. The sample consists of 3,107 persons (55 to 85 years) participating in the Longitudinal Aging Study Amsterdam. MANOVA, adjusted for covariates, was used to test the effect of hearing impairment on the combined outcomes. The association of hearing impairment and chronic diseases with psychosocial status was studied using multivariate regression analyses. RESULTS. Hearing impaired elderly report significantly more depressive symptoms, lower self-efficacy and mastery, more feelings of loneliness, and a smaller social network than normally hearing peers. Whereas chronic diseases show significant associations with some outcomes, hearing impairment is significantly associated with all psychosocial variables. DISCUSSION. The findings emphasize the negative effect of hearing impairment on quality of life.  相似文献   
24.
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
25.
The incidence, etiology, outcome, and risk factors for developing pneumonia late after hematopoietic stem cell transplantation (SCT) were investigated in 1359 patients transplanted in Seattle. A total of 341 patients (25% of the cohort) developed at least one pneumonic episode. No microbial or tissue diagnosis (ie clinical pneumonia) was established in 197 patients (58% of first pneumonia cases). Among the remaining 144 patients, established etiologies included 33 viral (10%), 31 bacterial (9%), 25 idiopathic pneumonia syndrome (IPS, 7%), 20 multiple organisms (6%), 19 fungal (6%), and 16 Pneumocystis carinii pneumonia (PCP) (5%). The overall cumulative incidence of first pneumonia at 4 years after discharge home was 31%. The cumulative incidences of pneumonia according to donor type at 1 and 4 years after discharge home were 13 and 18% (autologous/syngeneic), 22 and 34% (HLA-matched related), and 26 and 39% (mismatched related/unrelated), respectively. Multivariate analysis of factors associated with development of late pneumonia after allografting were increasing patient age (RR 0.5 for <20 years, 1.2 for >40 years, P=0.009), donor HLA-mismatch (RR 1.6 for unrelated/mismatched related, P=0.01), and chronic graft-versus-host disease (GVHD; RR 1.5, P=0.007). Our data suggest that extension of PCP prophylaxis may be beneficial in high-risk autograft recipients. Further study of long-term anti-infective prophylaxis based on patient risk factors after SCT appear warranted.  相似文献   
26.
Four patients with paroxysmal nocturnal hemoglobinuria and severe marrow aplasia were given marrow grafts either from allogeneic human-leukocyte-antigen-identical siblings (three patients) or from a syngeneic donor (one patient). The patients with allogeneic grafts were conditioned with regimens that included cyclophosphamide and had sustained and complete marrow engraftment; subsequent tests were negative for paroxysmal nocturnal hemoglobinuria. One patient developed chronic graft-versus-host disease that resolved over 4 years. The patient receiving a syngeneic graft received marrow infusion without preceding immunosuppression. He had prompt engraftment, and hematologic variables returned to normal. A Ham's test done at 3 years was negative, but a complement lysis sensitivity test done 10 years after grafting was positive; the patient, however, remains asymptomatic. All four patients are alive and well 4, 9, 10, and 12 years after transplantation. Paroxysmal nocturnal hemoglobinuria apparently can be treated successfully by allogeneic or syngeneic marrow transplantation without subsequent maintenance therapy.  相似文献   
27.
28.
Self-rated health (SRH) may have different implications in various social and cultural settings. However, few studies are available concerning SRH among older persons across countries. The aim of this study was to analyse whether there are cross-national differences in the association between status characteristics, several diseases common among older persons, activities of daily living (ADL), and SRH. The study base was the Comparison of Longitudinal European Studies on Aging (CLESA), which includes data from six population-based studies on aging conducted in Finland, Israel, Italy, The Netherlands, Spain and Sweden. The study population comprised 5,629 persons, with participants from all countries except Italy. Logistic regression analyses were used to assess the relationship between status characteristics, health conditions, ADL and SRH. To examine whether the association among status characteristics, health conditions, ADL and outcome differed across the CLESA countries, interaction terms defined as variable*country were considered separately for each variable. Regression analyses revealed that sex, education, lifetime occupation, heart disease and respiratory disease were differently distributed across countries. Among homogeneous factors, marital status (OR=1.21), hypertension (OR=1.41), stroke (OR=1.67), diabetes (OR=2.15), cancer (OR=1.47), musculoskeletal diseases (OR=2.44), and ADL (OR=2.72) turned out to be significantly associated with fair or poor SRH. The results indicate that there are differences in self-ratings of health across countries. These differences cannot be explained entirely by status characteristics, self-reported diseases or functional ability. However, an important finding was that in all countries most of the indicators of medical and functional health were homogeneously associated with SRH.  相似文献   
29.
Fifty patients with severe aplastic anemia had no transfusions of blood products until just before marrow transplantation from HLA-identical family members. Of the 50, 42 are still alive 1 to 12 years after transplantation (median, 7 years). By actuarial standards, the 10-year probability of survival is 82%. Of the 42 surviving patients, 37 have Karnofsky performance status scores of 100% and 5 with chronic graft-versus-host disease have scores ranging from 50% to 90% (median, 80%). The 8 deaths were caused by early infection in 1, graft rejection in 1, acute graft-versus-host disease in 3, and chronic graft-versus-host disease in 3. All deaths occurred within two years after transplantation. The incidence of graft failure was 10%. Acute graft-versus-host disease developed in 14 of 44 patients at risk and chronic graft-versus-host disease, in 15 of 41. Risk factors for development of chronic graft-versus-host disease included increased age (p = 0.008) and presence of acute graft-versus-host disease (p = 0.001). The only factor associated with increased risk of death was development of acute graft-versus-host disease (p = 0.05). Results of this study extend our previous finding that patients with severe aplastic anemia who have transplants before the onset of transfusion-induced sensitization have an excellent probability of long-term survival and a normal life.  相似文献   
30.
Ehninger  G; Schuler  U; Renner  U; Ehrsam  M; Zeller  KP; Blanz  J; Storb  R; Deeg  HJ 《Blood》1995,85(11):3247-3249
In a canine model we investigated the toxicity and pharmacokinetics of a water soluble busulfan preparation. Busulfan was dissolved in dimethylsulfoxide (DMSO) and administered either orally or intravenously in a single dose of 1 mg/kg. The application in either preparation was well tolerated. In seven dogs, peak levels in the range of 730 ng/mL to 1,000 ng/mL were measured after intravenous injection with an area under curve (AUC) of 75 ng.h/kg.mL to 146 ng.h/kg.mL. It was of note that even the oral administration of the same busulfan preparation resulted in AUC values in the same range as observed after parenteral application. The absorption rate of busulfan tablets in our model was as unpredictable as documented in clinical trials. On the basis of the present study, clinical trials using busulfan dissolved in DMSO given either intravenously or orally appear warranted. This approach should lead to predictable blood levels, reduced toxicity, and increased efficacy of busulfan-containing regimens.  相似文献   
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