Biomedical subjects

Subashan Perera

Publications and source records attributed to Subashan Perera.

27 records · Page 2Linked to original sources

PubMed2003

Rasch analysis of a new stroke-specific outcome scale: the Stroke Impact Scale.

OBJECTIVES: To assess multiple psychometric characteristics of a new stroke outcome measure, the Stroke Impact Scale (SIS), using Rasch analysis, and to identify and remove misfitting items from the 8 domains that comprise the SIS. DESIGN: Secondary analysis of 3-month outcomes for the Glycine Antagonist in Neuroprotection (GAIN) Americas randomized stroke trial. SETTING: A multicenter randomized trial performed in 132 centers in the United States and Canada. PARTICIPANTS: A total of 696 individuals with stroke who were community-dwelling and independent prior to acute stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Rasch analysis was performed using WINSTEPS, version 3.31, to evaluate 4 psychometric characteristics of the SIS: (1) unidimensionality or fit (the extent to which items measure a single construct), (2) targeting (the extent to which the items are of appropriate difficulty for the sample), (3) item difficulty (the ordering of items from least to most difficult to perform), and (4) separation (the extent to which the items distinguish distinct levels of functioning within the sample). RESULTS: (1) Within each domain, most of the items measured a single construct. Only 3 items misfit the constructs and were deleted ("add and subtract numbers," "get up from a chair," "feel emotionally connected") and 2 items ("handle money," "manage money") misfit the combined physical domain. These items were deleted to create SIS, version 3.0. (2) Overall, the items are well targeted to the sample. The physical and participation domains have a wide range of items that capture difficulties that most individuals with stroke experience in physical and role functions, while the memory, emotion, and communication domains include items that capture limitations in the most impaired patients. (3) The order of items from less to more difficult was clinically meaningful. (4) The individual physical domains differentiated at least 3 (high, average, low) levels of functioning and the composite physical domain differentiated more than 4 levels of functioning. However, because difficulties with communication, memory, and emotion were not as frequently reported and difficulties with hand function were more frequently reported, these domains only differentiated 2 (high, low) to 3 (high, average, low) strata of patients. Time from stroke onset to administration of the SIS had little effect on item functioning. CONCLUSION: Rasch analysis further established the validity of the SIS. The domains are unidimensional, the items have an excellent range of difficulty, and the domain scores differentiated patients into multiple strata. The activities of daily living/instrumental activities of daily living, mobility, strength, composite physical, and participation domains have the most robust psychometric characteristics. The composite physical domain is most able to discriminate difficulty in function in individuals after stroke, while the communication, memory, and emotion domain items only capture limitations in function in the more impaired groups of patients.

Activities of Daily Living↗

PubMed2003

Hospice usage by minorities in the last year of life: results from the National Mortality Followback Survey.

OBJECTIVES: To examine racial/ethnic variations in rates of hospice use in a national cohort and to identify individual characteristics associated with hospice use. DESIGN: Secondary analysis of the 1993 National Mortality Followback Survey (NMFS), a nationally obtained sample using death certificates and interviews with relatives (proxy respondents) to provide mortality, social, and economic data and information about healthcare utilization in the last year of life for 23,000 deceased individuals. SETTING: Hospice care. PARTICIPANTS: Individuals aged 15 and older who died in 1993. Subjects were included in this analysis if they died of nontraumatic causes (N = 11,291). MEASUREMENTS: Hospice use was dichotomized by proxy responses indicating use or nonuse of home or inpatient hospice services. The percentage of individuals using hospice services in the last year of life was calculated. RESULTS: Unadjusted bivariate results found that African Americans were less likely to use hospice than whites (odds ratio (OR) = 0.59; P <.001) and that those without a living will (LW) (OR = 0.23; P <.001) and without a cancer diagnosis (OR = 0.28; P <.001) were less likely to use hospice. The negative relationship between African Americans and hospice use was unaffected when controlled for sex, education, marital status, existence of a LW, income, and access to health care. Logistic models revealed that presence of a LW diminished the negative relationship between African Americans and hospice use, but the latter remained significant (OR = 0.83; P =.033). A subanalysis of subjects aged 55 and older showed a significant interaction between access to care and race/ethnicity with respect to hospice use (P =.044). Inclusion of income in this multivariable logistic model attenuated the relationship between African-American race/ethnicity and hospice use (OR = 0.77), and the difference between whites and African Americans became only marginally statistically significant (P =.060). CONCLUSION: In the 1993 NMFS, hospice use was negatively associated with African-American race/ethnicity independent of income and access to healthcare. The relationship is not independent of age, insurance type, or history of stroke. For subjects aged 55 and older, access to healthcare may be an important confounder of the negative relationship between African-American race/ethnicity and hospice use. Consistent with previous studies, this analysis found that African Americans were less likely to use LWs than whites. The reduced importance of African-American race/ethnicity on hospice use with the inclusion of presence of a LW in logistic models suggests that similar cultural processes may shape differences between African Americans and whites in advance care planning and hospice use.

Adolescent↗

PubMed2003

Physical performance measures in the clinical setting.

OBJECTIVES: To assess the ability of gait speed alone and a three-item lower extremity performance battery to predict 12-month rates of hospitalization, decline in health, and decline in function in primary care settings serving older adults. DESIGN: Prospective cohort study. SETTING: Primary care programs of a Medicare health maintenance organization (HMO) and Veterans Affairs (VA) system. PARTICIPANTS: Four hundred eighty-seven persons aged 65 and older. MEASUREMENTS: Lower extremity performance Established Population for Epidemiologic Studies of the Elderly (EPESE) battery including gait speed, chair stands, and tandem balance tests; demographics; health care use; health status; functional status; probability of repeated admission scale (Pra); and primary physician's hospitalization risk estimate. RESULTS: Veterans had poorer health and higher use than HMO members. Gait speed alone and the EPESE battery predicted hospitalization; 41% (21/51) of slow walkers (gait speed <0.6 m/s) were hospitalized at least once, compared with 26% (70/266) of intermediate walkers (0.6-1.0 m/s) and 11% (15/136) of fast walkers (>1.0 m/s) (P <.0001). The relationship was stronger in the HMO than in the VA. Both performance measures remained independent predictors after accounting for Pra. The EPESE battery was superior to gait speed when both Pra and primary physician's risk estimate were included. Both performance measures predicted decline in function and health status in both health systems. Performance measures, alone or in combination with self-report measures, were more able to predict outcomes than self-report alone. CONCLUSION: Gait speed and a physical performance battery are brief, quantitative estimates of future risk for hospitalization and decline in health and function in clinical populations of older adults. Physical performance measures might serve as easily accessible "vital signs" to screen older adults in clinical settings.

Aged↗

PubMed2003

Physical and social functioning after stroke: comparison of the Stroke Impact Scale and Short Form-36.

BACKGROUND AND PURPOSE: This study evaluated assessments of physical functioning and social functioning using the Stroke Impact Scale (SIS) and Short Form-36 (SF-36) to characterize health-related quality of life for patients after stroke. METHODS: The SIS and SF-36 were administered to 278 stroke subjects approximately 90 days after stroke. The SIS-16 and SF-36 Physical Functioning (PF) domain characterize physical function, whereas the SIS Participation and SF-36 Social Functioning (SF) domains characterize social function. Descriptive statistics and an analysis of variance were used to characterize physical and social functioning after stroke across levels of the modified Rankin Scale (MRS). Rasch analysis was used to compare the hierarchies and ranges of item difficulties in the SIS-16 and the SF-36 PF domains, as well as in the SIS Participation and the SF-36 SF domains. RESULTS: Item hierarchies for the SIS-16 and SF-36 PF domain demonstrate that the SIS-16 contains less difficult items that could differentiate physical function among patients with more severe limitations. Compared with the SF-36 SF domain, the item hierarchy for the SIS Participation domain contained more difficult items that could differentiate social function among patients who were more active. In contrast to SIS-16, the SF-36 PF has major floor effects. In contrast to SIS Participation, the SF-36 SF domain has major ceiling effects. Both SIS-16 and SF-36 PF were able to discriminate well among the MRS levels of 0 to 1, 2, 3, and 4. The SIS Participation domain was also able to discriminate across the MRS levels of 0 to 1, 2, and 3 to 4. On the other hand, the SF-36 SF was similar among MRS levels 0, 1, and 2 and among MRS levels 2, 3, and 4. CONCLUSIONS: Both the physical and participation subscales of the SIS cover a wider range of item difficulty than their counterparts from the SF-36. Compared with the SF-36 PF and SF domains, the SIS-16 and SIS Participation are better able to capture physical functioning and social well-being in patients with strokes.

Aged↗

PubMed2002

Persisting consequences of stroke measured by the Stroke Impact Scale.

BACKGROUND AND PURPOSE: The purpose of this study was to compare disability and quality of life as measured by the Stroke Impact Scale (SIS) of stroke patients deemed recovered (Barthel Index > or =95) with 2 stroke-free populations of community-dwelling elderly. METHODS: Eighty-one stroke patients who participated in the Kansas City Stroke Registry and achieved a Barthel Index of > or =95 at 3 months after stroke and 246 stroke-free subjects enrolled in the Community Elders Study were enrolled in this study. The Community Elders Study group was further divided into 2 groups, those recruited from the Department of Veterans Affairs Health System (VA) and a those from a local health maintenance organization (HMO). Stroke patients were administered the SIS approximately 90 days after stroke, and the stroke-free community dwellers were administered a version of the SIS adapted for nonstroke subjects, the Health Impact Scale (HIS). A general linear model was used to examine differences in health outcomes measured by the SIS or HIS between the KCSR stroke patients and VA and HMO community-dwelling elders after controlling for medical comorbidities and demographics. RESULTS: Kansas City Stroke Registry participants were significantly older than the community study groups (P=0.0052). Selected medical conditions were similar among the 3 study groups. Old age and a history of diabetes mellitus were more likely to be associated with more deficits and poor quality of life. In stroke patients deemed recovered, stroke still affected hand function, activities and independent activities of daily living, participation, and overall physical function compared with the stroke-free community dwellers in the HMO health system even after adjustment for age and diabetes status. Stroke-free community dwellers in the VA health system also had worse social participation than the stroke-free community dwellers in the HMO health system. CONCLUSIONS: Research and clinicians have consistently underestimated the impact of stroke with the Barthel Index. This has major implications for the design of therapeutic trial designs and adequate assessments of social and economic sequelae of stroke.

Aged↗

PubMed2002

Evaluation of proxy responses to the Stroke Impact Scale.

BACKGROUND AND PURPOSE: The purposes of this study were to compare proxy-patient responses on each domain of the Stroke Impact Scale (SIS) and the SIS-16, estimate the bias, and evaluate the validity of proxy scores. METHODS: Two hundred eighty-seven patient and proxy pairs from the Kansas City Stroke Registry participated in the study. All patients were assessed in their home or nursing facility between 90 and 120 days after stroke with the use of the modified Rankin Scale Motricity Index (strength), Barthel Index (activities of daily living), Lawton assessment (instrumental activities of daily living), Folstein Mini-Mental State Examination (cognition), and the SIS. Eligible proxies were individuals who were aged > or =18 years, had known the patient for at least 1 year, and saw the patient at least once each week. All proxy interviews were conducted within 7 days of (before or after) the patient's interview. RESULTS: Three hundred seventy-seven patients from the Kansas City Stroke Registry were eligible for the study. Seventy-seven patients or proxies refused participation. Thirteen patients of the consenting patient-proxy pairs were too aphasic or cognitively impaired to complete the interviews and were dropped from the study. Proxies scored patients as more severely affected than patients scored themselves on the SIS-16 and in 7 of 8 domains of the full SIS (5 were statistically significant at alpha=0.05). The proxy bias toward overrating the severity of the patient's condition tended to increase as the severity of the stroke increased. However, the magnitude of the biases between patient and proxy means, as measured by effect size, was small (range, -0.1 to 0.4). The strength of the agreement, as measured by intraclass correlation coefficients, between proxy and patient ranged from 0.50 to 0.83. Agreement was best for the observable physical domains. Both patient and proxy scores in all domains were significantly different across Rankin categories. Concurrent validity for both patient and proxy correlations with the Folstein Mini-Mental State Examination, Barthel Index, Lawton instrumental activities of daily living, and Motricity Index was good to excellent (range, 0.37 to 0.78). CONCLUSIONS: Proxies provide valid information for assessment of stroke outcomes. There are significant differences between patient and proxy reporting on SIS domains and the SIS-16. However, the observed biases are small and not clinically meaningful.

Activities of Daily Living↗

PubMedDate not supplied

Urban-rural patterns of increasing antidepressant use among nursing facility residents.

OBJECTIVE: To characterize changing patterns of antidepressant use in nursing facilities across the urban-rural continuum during the mid-1990s. DESIGN: Retrospective analysis of antidepressant drug codes and demographic/clinical data from the Minimum Data Set (MDS) 1994 to 1997. SETTING: Kansas nursing facilities. PARTICIPANTS: Facility residents aged 65 and older. MEASUREMENTS: We examined (1) admission use and (2) after-admission use for newer and older antidepressants for each year separately, using a 4-stratum system to classify nursing facility location by county, from urban to most rural. Incidence rate ratios were determined for antidepressant use in each stratum using the urban strata as the reference. RESULTS: Remarkable increases in use of newer antidepressants were seen over time in all strata, but use was highest in the urban area. Modest urban-rural gradient effects attenuated over time and were not consistently seen across analyses and years. Tricyclic antidepressant (TCA) use remained largely unchanged over time and at much lower rates than newer agents. However, TCA use was also modestly higher in urban areas. Differences were clearer for use after admission, in contrast with admission use patterns. CONCLUSIONS: Newer antidepressants were rapidly adopted across the urban-rural continuum from 1994 to 1997. Marked increases in both admission and after-admission use of newer antidepressants were seen. Both newer and older antidepressants were used at modestly higher rates in urban areas. Further work is needed to elucidate the patient, prescriber, and facility factors that explain these prescribing patterns.

Aged↗

PubMedDate not supplied

Religion, spirituality, and health status in geriatric outpatients.

BACKGROUND: Religion and spirituality remain important social and psychological factors in the lives of older adults, and there is continued interest in examining the effects of religion and spirituality on health status. The purpose of this study was to examine the interaction of religion and spirituality with self-reported health status in a community-dwelling geriatric population. METHODS: We performed a cross-sectional analysis of 277 geriatric outpatients participating in a cohort study in the Kansas City area. Patients underwent a home assessment of multiple health status and functional indicators by trained research assistants. A previously validated 5-item measure of religiosity and 12-item spirituality instrument were embedded during the final data collection. Univariate and multivariate analyses were performed to determine the relationship between each factor and self-reported health status. RESULTS: In univariate analyses, physical functioning (P < .01), quality of life (P < .01), race (P < .01), depression (P < .01), age (P = .01), and spirituality (P < .01) were all associated with self-reported health status, but religiosity was not (P = .12). In a model adjusted for all covariates, however, spirituality remained independently associated with self-appraised good health (P = .01). CONCLUSIONS: Geriatric outpatients who report greater spirituality, but not greater religiosity, are more likely to appraise their health as good. Spirituality may be an important explanatory factor of subjective health status in older adults.

Activities of Daily Living↗

PubMedDate not supplied

Urban-rural differences in amitriptyline use among nursing facility residents.

OBJECTIVE: To characterize patterns of amitriptyline use across the urban-rural continuum. DESIGN: Retrospective analysis of antidepressant drug codes and demographic and clinical data from the Minimum Data Set (MDS), 1994 to 1997. SETTING: Kansas nursing facilities. PARTICIPANTS: Facility residents aged 65 and older. MEASURES: A four-strata system was used to classify nursing facility location by county, from urban to frontier. We examined admission use and after-admission use of amitriptyline across strata for each year separately. Unadjusted and adjusted odds ratios were determined for each stratum, using the urban stratum as the point of reference. RESULTS: Admission use of amitriptyline occurred in 2.3 to 4% of all admissions, and although such use was highest in the most rural stratum, no clear urban-rural gradient was found. In contrast, amitriptyline use 30 days or more after admission demonstrated modest urban-rural gradients in unadjusted and adjusted analyses. In 1997, when adjusted for demographic factors, odds ratios for amitriptyline use were 2.10 (1.54-2.87), 1.68 (1.33-2.13), and 1.49 (1.17-1.90) for the Frontier, Rural, and Densely Settled Rural categories as compared with the Urban reference group. CONCLUSIONS: After admission to Kansas nursing facilities, rural practice patterns for amitriptyline use are less favorable than those in urban areas, and an urban-rural gradient is identified. Further work is needed to identify explanatory patient, facility, and prescriber factors.

Journal Article↗