Biomedical subjects

S F Assmann

Publications and source records attributed to S F Assmann.

At least 19 recordsLinked to original sources

PubMed2004

Quality of life in diverse groups of midlife women: assessing the influence of menopause, health status and psychosocial and demographic factors.

This paper examines whether menopausal status is associated with global quality of life (QOL) among women aged 40-55 and whether this association varies by race/ethnicity. We further examine the contributions of other health-related and psychosocial factors to QOL and whether these associations vary by racial/ethnic group. Analyses are based on 13,874 women who participated in the multi-ethnic, multi-race study of mid-aged women called the Study of Women's Health Across the Nation (SWAN). Study participants completed a 15-min telephone or in-person interview that contained questions on a variety of health-related topics. Items of interest for these analyses include global QOL, menstrual history (to assess menopausal status), sociodemographics, health status, lifestyle, and psychosocial variables. Results showed that in unadjusted analyses, early perimenopausal women reported lower QOL compared with premenopausal women, but menopausal status was no longer associated with QOL when analyses were adjusted for other variables. In multivariable models, being married and having low levels of perceived stress were associated with better QOL across all racial/ethnic groups. While there were many consistencies across racial/ethnic groups, we also found that the nature of the associations between QOL and education, marital status, perceived stress and social support varied across racial/ethnic groups.

Adult↗

PubMed2002

A prospective, randomized clinical trial of universal WBC reduction.

BACKGROUND: Recipient exposure to allogeneic donor WBCs results in transfusion complications for selected populations of recipients. Whether or not WBC reduction should be universally applied is highly controversial. STUDY DESIGN AND METHODS: In a general hospital, a randomized, controlled clinical trial of conversion to universal WBC reduction was conducted. Patients (11%) with established medical indications for WBC-reduced blood were not eligible. All other patients who required transfusion were assigned at random to receive either unmodified blood components or stored WBC-reduced RBCs and platelets. Analysis for each patient was restricted to the first hospitalization. RESULTS: All eligible patients (n = 2780) were enrolled. Three specified primary outcome measures were not different between the two groups: 1) in-hospital mortality (8.5% control; 9.0% WBC-reduced; OR, 0.94 [95% CI, 0.72-1.22]; p = 0.64); 2) hospital length of stay (LOS) after transfusion (median number of days, 6.4 for control and 6.3 for WBC-reduced; p = 0.21); and 3) total hospital costs (median, $19,500 for control and $19,200 for WBC-reduced, p = 0.24). Secondary outcomes (intensive care LOS, postoperative LOS, antibiotic usage, and readmission rate) were not different between the two groups. Subgroup analysis based on patient age, sex, amount of blood transfused, or category of surgical procedure showed no effect of WBC reduction. Patients who received WBC-reduced blood had a lower incidence of febrile reactions (p = 0.06). CONCLUSION: A beneficial effect of conversion from selective to universal WBC reduction was not demonstrated.

Adolescent↗

PubMed2002

Subtle developmental abnormalities in the inferior olive: an indicator of prenatal brainstem injury in the sudden infant death syndrome.

Subtle quantitative abnormalities in neuronal populations derived from the rhombic lip (i.e. arcuate nucleus at the ventral medullary surface, external granular layer of the cerebellum) have been reported in victims of the sudden infant death syndrome (SIDS). In this study, we examined the inferior olive, a major rhombic lip derivative, to determine if subtle rhombic lip abnormalities also involve this nucleus in SIDS. We analyzed the number and density of neurons and reactive astrocytes in the inferior olive in 29 SIDS cases and 29 controls. Computer-assisted cell counting procedures were used in sections stained with hematoxylin and eosin/Luxol fast blue. There was a significant difference in the postconceptionally age-adjusted mean for neuronal density between SIDS cases (7,687 +/- 255 neurons/mm(3)) and controls (8,889 +/- 255 neurons/mm(3)) (p = 0.002). The difference in age-adjusted mean neuronal number between SIDS cases (1,932 +/- 89 neurons/2 sections) and controls (2,172 +/- 89 neurons/2 sections) was marginally significant (p = 0.063). Reactive astrocytes were present in the inferior olive in SIDS cases, but their number, density, and developmental profile were not significantly different from that of control infants dying of diverse known causes. SIDS victims found dead in cribs, beds, and sofas, prone or supine had subtle olivary abnormalities, suggesting that affected infants are at risk in various sleeping situations. We propose that at least some SIDS victims experience intrauterine brainstem injury including the olivo-arcuato-cerebellar circuitry derived from the rhombic lip. These observations provide future directions for SIDS research concerning the role of early insults in pregnancy, the rhombic lip, and the interactions of the ventral medulla and cerebellum in cardioventilatory control.

Age Factors↗

PubMed2001

Differences in difficulty adjudicating clinical events in patients with advanced HIV disease.

Adjudication of clinical events is often used as a quality assurance method in clinical research. During the design of the Viral Activation Transfusion Study (a clinical trial in patients with advanced HIV disease), a set of study endpoints was defined (primarily AIDS-defining conditions), criteria for confirmation of each event type were developed, and an adjudication procedure was established. The adjudication process included 1) an initial review of documentation of each event by two independent reviewers, 2) the opportunity to request additional information, 3) a second review either of additional documentation or of cases in which there was disagreement on first review, and 4) the consultation of a third reviewer if there was still disagreement. Overall, of 288 reported endpoints, 30% required additional documentation or more than one review, and 16% were not confirmed at the end of the adjudication process. However, these percentages varied widely over different types of events. For example, of 30 reported nonophthalmalogic cytomegalovirus events, 37% required additional documentation and 40% were not confirmed. In contrast, every one of 17 reported Pneumocystis cariini pneumonias were confirmed with no requirement for additional documentation. The results can be used to help design endpoint documentation and adjudication procedures for other studies, thereby improving data quality and reducing costs.

AIDS-Related Opportunistic Infections↗

PubMed2001

Survival of transfused donor white blood cells in HIV-infected recipients.

The appearance and expansion of donor white blood cells in a recipient after transfusion has many potential biologic ramifications. Although patients with HIV infection are ostensibly at high risk for microchimerism, transfusion-associated graft-versus-host disease (TA-GVHD) is rare. The purpose of this study was to search for sustained microchimerism in such patients. Blood samples were collected from 93 HIV-infected women (a subset from the Viral Activation Transfusion Study, an NHLBI multicenter randomized trial comparing leukoreduced versus unmodified red blood cell [RBC] transfusions) before and after transfusions from male donors. Donor lymphocytes were detected in posttransfusion specimens using a quantitative Y-chromosome-specific polymerase chain reaction (PCR) assay, and donor-specific human leukocyte antigen (HLA) alleles were identified with allele-specific PCR primers and probes. Five of 47 subjects randomized to receive nonleukoreduced RBCs had detectable male lymphocytes 1 to 2 weeks after transfusion, but no subject had detectable male cells more than 4 weeks after a transfusion. In 4 subjects studied, donor-specific HLA haplotypes were detected in posttransfusion specimens, consistent with one or more donors' cells. None of 46 subjects randomized to receive leukoreduced RBCs had detectable male lymphocytes in the month after transfusion. Development of sustained microchimerism after transfusion in HIV-infected patients is rare; HIV-infected patients do not appear to be at risk for TA-GVHD.

Adult↗

PubMed2001

Highly active antiretroviral therapy decreases mortality and morbidity in patients with advanced HIV disease.

BACKGROUND: Mortality and morbidity related to AIDS have decreased among HIV-infected patients taking highly active anti-retroviral therapy (HAART), but previous studies may have been confounded by other changes in treatment. OBJECTIVE: To assess the benefit of HAART in patients with advanced AIDS and anemia. DESIGN: Prospective, multicenter cohort study. SETTING: The Viral Activation Transfusion Study (VATS), with enrollment from August 1995 through July 1998 and follow-up through June 1999. PATIENTS: 528 HIV-infected patients with cytomegalovirus (CMV) seropositivity or disease who were receiving a first red blood cell transfusion for anemia. MEASUREMENTS: In a person-year analysis of follow-up before and after initiation of HAART, Poisson regression was used to calculate crude rate ratios and rate ratios adjusted for CD4 count, HIV RNA level, calendar period, time on study, sex, ethnicity, and injection drug use. RESULTS: At baseline, patients had a median CD4(+) lymphocyte count of 0.015 x 10(9) cell/L, median plasma HIV RNA level of 4.8 log(10) copies/mL, and median hemoglobin concentration of 73 g/L. Use of HAART increased from 1% of active patients in January 1996 to 79% of active patients in January 1999. The crude death rate was 0.24 event/person-year among patients taking HAART and 0.88 event/person-year among those not taking HAART (rate ratio, 0.26; adjusted rate ratio, 0.38; P < 0.001 for both comparisons). Rates of non-CMV disease were 0.15 event/ person-year after HAART and 0.45 event/person-year before HAART (crude rate ratio, 0.34 [ P < 0.001]; adjusted rate ratio, 0.66 [ P < 0.05]). Rates of CMV disease were 0.10 event/person-year after HAART and 0.25 before HAART (crude rate ratio, 0.42 [ P < 0.01]; adjusted rate ratio, 1.01 [ P > 0.2]). Results were similar in patients with baseline CD4(+) lymphocyte counts less than 0.010 x 10(9) cells/L. CONCLUSIONS: The data support an independent reduction in mortality and opportunistic events attributable to HAART, even in patients with very advanced HIV disease. However, patients with CMV infection or disease may not have a reduction in new CMV events due to HAART.

AIDS-Related Opportunistic Infections↗

PubMed2001

Leukocyte-reduced red blood cell transfusions in patients with anemia and human immunodeficiency virus infection: the Viral Activation Transfusion Study: a randomized controlled trial.

CONTEXT: Allogeneic blood transfusions have immunomodulatory effects and have been associated with activation of human immunodeficiency virus (HIV) and cytomegalovirus (CMV) in vitro and of HIV in small pilot studies. Retrospective studies suggest that transfusions adversely affect the clinical course of HIV. Data in selected non-HIV-infected patients requiring blood transfusion have suggested clinical benefit with leukocyte-reduced red blood cells (RBCs). OBJECTIVE: To compare the effects of leukoreduced and unmodified RBC transfusions on survival, complications of acquired immunodeficiency syndrome, and relevant laboratory markers in HIV-infected patients. DESIGN AND SETTING: Double-blind randomized controlled trial conducted in 11 US academic medical centers from July 1995 through June 1999, with a median follow-up of 12 months (24 months in survivors). PATIENTS: A total of 531 persons infected with HIV and CMV, aged 14 years or older, who required transfusions for anemia; 259 received leukoreduced transfusions and 262 received unmodified transfusions (10 did not receive the planned transfusion). MAIN OUTCOME MEASURES: Survival and change in plasma HIV RNA level 7 days after transfusion, compared by type of transfusion. RESULTS: At entry, the groups were similar in demographic, clinical, and relevant laboratory characteristics. A total of 3864 RBC units were transfused. Two hundred eighty-nine deaths occurred (151 with leukoreduced transfusion; 138 with unmodified transfusion); median survival was 13.0 and 20.5 months, respectively (relative hazard [RH], 1.20; 95% confidence interval [CI], 0.95-1.51; log-rank P =.12). Analyses adjusted for prognostic factors suggested possible worse survival with leukoreduction (RH, 1.35; 95% CI, 1.06-1.72). There was no difference in time to new opportunistic event/death or frequency of transfusion reactions. No changes in plasma HIV RNA level were seen in either group at days 7, 14, 21, or 28, even in patients not taking antiretroviral drugs. There were no differences in trends between groups in CMV DNA, CD4 cell counts, activated (CD38% or human leukocyte antigen-DR) CD8 cell counts, or plasma cytokine levels. CONCLUSIONS: We found no evidence of HIV, CMV, or cytokine activation following blood transfusion in patients with advanced HIV infection. Leukoreduction provided no clinical benefit in these patients. These data demonstrate the importance of conducting controlled studies of effects of leukoreduction in different patient populations, since smaller studies in other patient populations have suggested leukoreduction may be beneficial.

AIDS-Related Opportunistic Infections↗

PubMed2001

Number of RBC units and rate of transfusionto anemic HIV-positive patients assigned to receiveWBC-reduced or non-WBC-reduced RBCs: the viral activation transfusion study experience.

BACKGROUND: It is known that the use of filtration to reduce WBCs in RBC units is associated with a 6- to 15-percent loss of RBCs. It is not known if the use of such WBC-reduced RBCs results in an increased need for RBC units or in the transfusion of more units per year to patients with anemia. STUDY DESIGN AND METHODS: In the multicenter Viral Activation Transfusion Study (VATS), anemic HIV-positive patients were randomly assigned to receive either WBC-reduced or non-WBC-reduced RBCs. The number of RBC units transfused per patient and the rate of RBC use were studied. All RBC units given after the enrollment transfusion were counted, until the end of follow-up or the occurrence of bleeding (receiving >5 RBCs within 2 consecutive days). RESULTS: As expected, the WBC-reduced RBC units in VATS were lighter in weight than the non-WBC-reduced units (median weight: WBC-reduced, 300 g; non-WBC-reduced, 330 g; p<0.0001). After the enrollment transfusion, 258 WBC-reduced arm patients received 1279 units of RBCs (average, 5.0 units/patient, median, 2 units) while 262 patients in the non-WBC-reduced arm received 1111 RBCs (4.2 units/patient; median, 2 units). The number of units transfused for anemia was slightly greater in the WBC-reduced arm, but the difference was not significant (p = 0.41). Similarly, the rate of RBC use was somewhat higher in the WBC-reduced arm, but the difference was not significant (p = 0.14). The median was 2.3 units per patient per year of follow-up in the WBC-reduced arm; the median in the non-WBC-reduced arm was 1.2 units. CONCLUSION: This study confirms that WBC-reduced RBC units are significantly lighter in weight than non-WBC-reduced RBCs. However, in the setting of a large, randomized, blinded study of transfusion for anemia, the smaller size of the WBC-reduced RBC units had no significant effect on the number of RBC units transfused or on the rate at which RBC units were used. In this study, the frequency of blood transfusion may have had a greater relationship to the frequency of routine, scheduled appointments or transfusion orders for a specified Hb trigger than to the actual Hb content of the unit.

Anemia↗

PubMed2001

WBC reduction in RBC concentrates by prestorage filtration: multicenter experience.

BACKGROUND: As universal leukocyte (WBC) reduction (ULR) is being considered as a new standard, few data are available on the performance of WBC-reduction filtration in routine practice. The performance of WBC-reduction in RBCs, using varied filtration practices, in meeting the current FDA requirement (<5 x 10(6)), Council of Europe (EC) recommendation, the proposed FDA requirement (<1 x 10(6)), and a more stringent proposal (<5 x 10(5)) for residual WBCs per RBC unit was assessed and compared. STUDY DESIGN AND METHODS: Participating facilities were the 11 sites of the Viral Activation Transfusion Study (VATS), a prospective study of the impact of transfusion with and without WBC-reduction on survival and HIV viral load in HIV-1-infected patients. Patients randomly assigned to undergo WBC reduction were required to receive RBCs < or =14 days old that had undergone prestorage (within 72 hours of collection) WBC-reduction filtration by a method devised to achieve a postfiltration WBC count of <5 x 10(6). Residual WBC quantitation was performed by PCR in the central VATS laboratory by using frozen WBC-reduced RBC samples obtained at issue for transfusion. RESULTS: A total of 1869 WBC-reduced RBC units were studied. Filtration practices varied within and between sites. There were significant differences in mean residual WBC counts at the 11 sites (p<0.001). Among the WBC-reduced RBC units, 0.8 percent exceeded 5 x 10(6) WBCs per unit, 8.3 percent exceeded 1 x 10(6) WBCs per unit, and 14.3 percent exceeded 5 x 10(5) WBCs per unit. CONCLUSION: Residual WBCs in WBC-reduced RBC units vary within and between sites. WBC reduction was successful, in that over 99 percent and 91 percent of VATS WBC-reduced RBC units met US and EC thresholds, respectively. However, the small but measurable failure rate indicates that not every unit will meet these guidelines.

Blood Component Removal↗

PubMed2000

Determinants of antimicrobial prophylaxis use and treatment for wasting among patients with advanced human immunodeficiency virus disease in the United States, 1995-1998.

Despite US Public Health Service (USPHS) recommendations for antimicrobial prophylaxis for patients with advanced human immunodeficiency virus (HIV) disease, the proportion of patients who receive prophylaxis is not known. We measured the prevalence of antimicrobial prophylaxis use, and treatment for HIV wasting at baseline among 531 patients with advanced HIV disease enrolled in a multicenter randomized trial of red blood cell transfusion. Use of antimicrobial prophylaxis and treatment for wasting in the 30 days before enrollment was ascertained in patients eligible for primary prophylaxis, secondary prophylaxis, or both, according to USPHS guidelines. There was high utilization of primary and secondary Pneumocystis carinii pneumonia prophylaxis, variability in primary Mycobacterium avium complex prophylaxis by center, and low use of primary cytomegalovirus prophylaxis. Treatment of wasting was more common in white than nonwhite patients and in patients with HIV disease who lived in the region west of the Mississippi River of the United States versus those whose lived in the eastern region.

AIDS-Related Opportunistic Infections↗

PubMed2000

Subgroup analysis and other (mis)uses of baseline data in clinical trials.

BACKGROUND: Baseline data collected on each patient at randomisation in controlled clinical trials can be used to describe the population of patients, to assess comparability of treatment groups, to achieve balanced randomisation, to adjust treatment comparisons for prognostic factors, and to undertake subgroup analyses. We assessed the extent and quality of such practices in major clinical trial reports. METHODS: A sample of 50 consecutive clinical-trial reports was obtained from four major medical journals during July to September, 1997. We tabulated the detailed information on uses of baseline data by use of a standard form. FINDINGS: Most trials presented baseline comparability in a table. These tables were often unduly large, and about half the trials inappropriately used significance tests for baseline comparison. Methods of randomisation, including possible stratification, were often poorly described. There was little consistency over whether to use covariate adjustment and the criteria for selecting baseline factors for which to adjust were often unclear. Most trials emphasised the simple unadjusted results and covariate adjustment usually made negligible difference. Two-thirds of the reports presented subgroup findings, but mostly without appropriate statistical tests for interaction. Many reports put too much emphasis on subgroup analyses that commonly lacked statistical power. INTERPRETATION: Clinical trials need a predefined statistical analysis plan for uses of baseline data, especially covariate-adjusted analyses and subgroup analyses. Investigators and journals need to adopt improved standards of statistical reporting, and exercise caution when drawing conclusions from subgroup findings.

Bias↗

PubMed1999

Knowledge of cardiovascular disease prevention: an analysis from two New England communities.

BACKGROUND: Cardiovascular disease (CVD) mortality has been decreasing in the United States, possibly due in part to educational programs about CVD prevention. This study investigates CVD risk-reduction knowledge among demographic subgroups in two New England cities and how the level of knowledge changed in these subgroups over time. METHODS: Six independent cross-sectional surveys including a series of open-ended recall CVD knowledge questions were conducted biennially from 1981 to 1993 as part of the outcome evaluation for the Pawtucket Heart Health Program. We constructed a raw CVD knowledge score and then created an analysis of variance model with knowledge score as the dependent variable and explanatory variables including demographics, survey, and city. RESULTS: CVD prevention knowledge improved significantly over time in both cities and in every demographic subgroup, increasing rapidly from 1981 to about 1988 and then plateauing between 1988 and 1993. Adjusted knowledge scores were higher for people born in the United States, women, more educated individuals, and those who spoke English at home. The increase in knowledge over time came mainly from an increase in the identification of physical inactivity, and blood cholesterol/high fat diet as CVD risk factors, while there was a decrease in the identification of overweight and blood pressure. CONCLUSIONS: In order to assure that reductions in CVD morbidity and mortality will be sustained, national educational efforts which stress behavior change skills as well as knowledge must continue. These programs should focus particularly on higher risk subgroups, and risk factors such as weight reduction and blood pressure control should be special priorities.

Adolescent↗

PubMed1999

Distinguishing between quality of life and health status in quality of life research: a meta-analysis.

Despite the increasing acceptance of quality of life (QOL) as a critical endpoint in medical research, there is little consensus regarding the definition of this construct or how it differs from perceived health status. The objective of this analysis was to understand how patients make determinations of QOL and whether QOL can be differentiated from health status. We conducted a meta-analysis of the relationships among two constructs (QOL and perceived health status) and three functioning domains (mental, physical, and social functioning) in 12 chronic disease studies. Instruments used in these studies included the RAND-36, MOS SF-20, EORTC QLQ-30, MILQ and MQOL-HIV. A single, synthesized correlation matrix combining the data from all 12 studies was estimated by generalized least squares. The synthesized matrix was then used to estimate structural equation models. The meta-analysis results indicate that, from the perspective of patients, QOL and health status are distinct constructs. When rating QOL, patients give greater emphasis to mental health than to physical functioning. This pattern is reversed for appraisals of health status, for which physical functioning is more important than mental health. Social functioning did not have a major impact on either construct. We conclude that quality of life and health status are distinct constructs, and that the two terms should not be used interchangeably. Many prominent health status instruments, including utility-based questionnaires and health perception indexes, may be inappropriate for measuring QOL. Evaluations of the effectiveness of medical treatment may differ depending on whether QOL or health status is the study outcome.

Health Status↗

PubMed1999

Exercise--it's never too late: the strong-for-life program.

OBJECTIVES: This investigation determined whether an in-home resistance training program achieved health benefits in older adults with disabilities. METHODS: A randomized controlled trial compared the effects of assigning 215 older persons to either a home-based resistance exercise training group or a waiting list control group. Assessments were conducted at baseline and at 3 and 6 months following randomization. The program consisted of videotaped exercise routines performed with elastic bands of varying thickness. RESULTS: High rates of exercise adherence were achieved, with 89% of the recommended exercise sessions performed over 6 months. Relative to controls, subjects who participated in the program achieved statistically significant lower extremity strength improvements of 6% to 12%, a 20% improvement in tandem gait, and a 15% to 18% reduction in physical and overall disability at the 6-month follow-up. No adverse health effects were encountered. CONCLUSIONS: These findings provide important evidence that home-based resistance exercise programs designed for older persons with disabilities hold promise as an effective public health strategy.

Aged↗

PubMed1998

Tritiated-naloxone binding to brainstem opioid receptors in the sudden infant death syndrome.

The sudden infant death syndrome (SIDS) is defined as the sudden death of an infant under 1 year of age that remains unexplained after a thorough case investigation, including a complete autopsy. We hypothesized that SIDS is associated with altered 3H - naloxone binding to opioid receptors in brainstem nuclei related to respiratory and autonomic control. We analyzed 3H - naloxone binding in 21 regions in SIDS and control brainstems using quantitative tissue receptor autoradiography. Three groups were analyzed: SIDS (n = 45); acute controls (n = 14); and a chronic group with oxygenation disorders (n = 15). Opioid binding was heavily concentrated in the caudal nucleus of the solitary tract, nucleus parabrachialis medialis, spinal trigeminal nucleus, inferior olive, and interpeduncular nucleus in all cases analyzed (n = 74). The arcuate nucleus on the ventral medullary surface contained negligible binding in all cases (n = 74), and therefore binding was not measurable at this site. We found no significant differences among the three groups in the age-adjusted mean 3H - naloxone binding in 21 brainstem sites analyzed. The only differences we have found to date between SIDS and acute controls are decreases in 3H - quinuclidinyl benzilate binding to muscarinic cholinergic receptors and in 3H - kainate binding to kainate receptors in the arcuate nucleus in alternate sections of this same data set. The present study suggests that there is not a defect in opioid receptor binding in cardiorespiratory nuclei in SIDS brainstems.

Autoradiography↗

PubMed1998

Moderate exercise improves gait stability in disabled elders.

BACKGROUND: Decreased muscle strength impedes elders' functional performance in daily activities such as gait. The mechanisms whereby increased strength improves gait are unknown. METHODS: A prospective, blinded, randomized trial of moderate intensity strength exercise was conducted and its impact was measured on functional mobility during gait in 132 functionally limited elders. Lower extremity strength was measured, including hip abductor, hip extensor, and knee extensor strength. Of the 132 subjects, 120 subjects (mean age, 75.1 yrs) completed 6 months of elastic band resistance training at least 3 times a week or served as no-exercise controls. RESULTS: Subjects increased their lower extremity strength in the exercise and control groups, by 17.6% and 7.3% (p < .01), respectively. Gait stability improved significantly more in the exercise group than in the control group (p < .05). Increases in forward gait velocity were not significantly different between groups. Peak mediolateral velocity and base of support improved in the exercise group, but not in the control group. Change in lower extremity strength correlated significantly but weakly with many of the gait variables. CONCLUSIONS: Gait stability, especially mediolateral steadiness, improved in the exercise group but not in the control group. These results show that even moderate strength gains benefit gait performance in elders and thus provide a sound basis for encouraging low-intensity strength training for elders with functional limitations.

Activities of Daily Living↗

PubMed1998

Quality of the caregiver--care recipient relationship: does it offset negative consequences of caregiving for family caregivers?

This study examined whether relationship quality mediates, moderates, or both mediates and moderates the associations between caregiving stressors (e.g., disability and behavioral problems) and negative consequences associated with caregiver well-being (overload, role captivity, and depression). Data on family (spouses and children) caregivers (n = 118) came from a longitudinal study of a representative sample of disabled older people and their primary caregivers. Relationship quality mediated the linkages between the presence of problem behaviors and the outcomes of role captivity and depression. That is, when problem behaviors were present, they related to higher levels of captivity and depression because quality of the relationship suffered. Relationship quality moderated the linkage between disability and overload. Specifically, for those with a higher quality of relationship, increased disability was related to higher levels of perceived overload.

Adult↗

PubMed1998

Interrelationships among disablement concepts.

BACKGROUND: Understanding interrelationships among disablement concepts is critical to the design of future disability treatment and prevention interventions. METHODS: This study uses cross-sectional data to examine the relationships among physiologic impairments, functional limitations, and disability in a moderately disabled sample of 207 community-dwelling older adults. RESULTS: As hypothesized, the data revealed statistically significant curvilinear relationships of upper and lower extremity strength and balance with mobility in this older sample. Multivariate analyses further clarified the hypothesized causal mechanism among the disablement concepts by demonstrating that most of the association of muscle strength and balance with disability was through the intermediary role of mobility limitations. CONCLUSIONS: The findings from this study highlight the value of clinical trials that focus on prevention or treatment of mobility limitations as a means of preventing disability; our findings underscore the need for future research that examines the effects of other variables believed to influence disablement in late life.

Aged↗