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Biomedical subjects

D O Clark

Publications and source records attributed to D O Clark.

At least 19 recordsLinked to original sources
PubMed2001

Assessing the association of walking with health services use and costs among socioeconomically disadvantaged older adults.

BACKGROUND: The costs of physical inactivity are beginning to be recognized. Research to pinpoint these costs will provide needed information for researchers and policy-makers to develop cost-effective physical activity promotion programs. We present the association of walking with health services use and costs within a sample of 695 older, urban primary care patients. METHODS: A survey provided most data, but utilization and cost data were obtained from a medical records system. Multivariate models were developed to assess the association of walking with health services use and costs, adjusting for sociodemographic characteristics, chronic disease, health status, and previous utilization. RESULTS: Thirty-eight percent of respondents reported walking 0 minutes per week, 49% walked 1 to 119 minutes, and 13% walked 120 minutes or more. In the multivariate analyses, a report of walking 120 or more minutes was associated with a lower risk of emergency room visit and hospital stay in the subsequent year. No association was found between walking and primary care visits and total cost. CONCLUSION: These analyses suggest an association of walking 120 minutes or more with decreased emergency room visits (OR = 0.5, P = 0.046) and hospital stays (OR = 0.6, P = 0.034). This suggests that physical activity promotion among socioeconomically disadvantaged older adults has the potential to provide cost savings. This will not be known, however, until physical activity can be promoted and maintained among these adults.

Aged↗
PubMed2001

Predictors of older primary care patients' participation in a submaximal exercise test and a supervised, low-impact exercise class.

OBJECTIVES: This study is an investigation of physical activity promotion among a nonvolunteer sample of community-dwelling, older, urban primary care patients. Our primary interest was in the rates of exercise test and class participation. Of secondary interest were the medical record and baseline survey predictors of test and class participation. METHODS: The first 500 nonterminally ill women ages 50 years or more with a visit at one of two predominantly African-American, inner-city primary care clinics received a physician screen, a referral to a submaximal exercise test, and, subsequently, a free, supervised exercise program located in a nearby community center. RESULTS: Eighty-one percent were eligible for the exercise test per provider screen. Of these, 29% completed the exercise test and 28% attended at least one exercise class. After 1 year, 9.2% were attending the exercise classes. Higher exercise outcome expectations, not smoking, and clinic site were associated with exercise test and class participation. CONCLUSIONS: Providing free, traditional exercise classes and a primary care referral to the classes resulted in limited physical activity participation among older, urban primary care patients. More development and testing of physical activity promotion programs are needed in this population.

Black or African American↗
PubMed2001

Prevalence and outcomes of comorbid metabolic and cardiovascular conditions in middle- and older-age adults.

UNLABELLED: To estimate age group differences in the prevalence and outcomes of three common and often comorbid metabolic conditions (i.e., obesity, hypertension, and diabetes) and heart disease. DESIGN: Nationally representative prospective cohort study. SETTING: PARTICIPANTS' homes. PARTICIPANTS: 9825 adults aged 51 to 61 years (middle-age) in 1992, and 7370 adults aged 70 years and over (older-age) in 1993. MEASUREMENTS: Two-year dichotomous outcomes included: doctor visits, hospitalization, mobility difficulty, activity of daily living limitation, poor perceived health, and mortality. Odds ratios (OR) were adjusted for sociodemographic characteristics and history of cancer or lung disease. RESULTS: Those with one condition represented 80% and 70% of the middle- and older-age groups, respectively, while just 1-2% of each age group reported all three metabolic conditions. Thirteen percent and 32%, respectively, reported heart disease with or without metabolic conditions. Diabetes comorbid with other metabolic conditions, and particularly with heart disease, substantially elevated the risk of adverse outcomes such as health-related quality of life deficits, health services use, and mortality in both middle- and older-age adults. In the middle-age group, the OR was 6.81 for mortality in patients with a combination of obesity and diabetes and 6.10 in those with a combination of heart disease and diabetes. There also were significant ORs for mortality in middle-aged patients with heart disease (OR = 2.40), diabetes (OR = 2.63) and for those with a combination of obesity, hypertension, and diabetes (OR = 3.26). CONCLUSION: The impact of these often comorbid conditions underscores the importance of targeted and aggressive prevention, particularly among middle-age adults.

Age Distribution↗
PubMed1999

Symptoms in hospitalized patients: outcome and satisfaction with care.

PURPOSE: Physical symptoms are responsible for substantial morbidity in outpatients. We assessed symptoms in patients admitted to a hospital to determine their frequency, persistence at discharge, and the relation between symptom outcome and satisfaction with care. METHODS: During a 12-month period, 2,126 hospitalized medical patients completed a study interview within 2 hours of admission. More than half (n = 1,168) of the patients were re-interviewed within 24 hours of discharge. We ascertained the presence and severity of 11 physical symptoms, as well as activities of daily living, mobility, mood, self-rated health, physiologic severity of illness, satisfaction with care, and length of stay. RESULTS: Symptoms were common at the time of hospital admission, particularly fatigue (80% of patients), dyspnea (60%), cough (51%), dizziness (51%), headache (47%), chest pain (46%), and nausea or vomiting (43%). Individual symptoms failed to resolve by hospital discharge approximately 25% to 50% of the time. The three most prominent predictors of persistence of symptoms were shorter length of stay, severity of the symptom on admission, and total symptom count. Patient satisfaction with care was associated with total symptom severity score at discharge and the degree of symptomatic improvement that had occurred during hospitalization. CONCLUSION: Because symptoms are common at discharge and associated with decreased satisfaction with care, asking about them would be a reasonable way to enhance patient-oriented care.

Hospital Bed Capacity, 300 to 499↗
PubMed1999

Validity and utility of patient-reported health measures on hospital admission.

Patient perceptions of their health are often inadequately captured and explored on hospital admission where physiologic and other objective measures are the focus of attention. Therefore, we conducted a prospective study to develop and validate measures of several domains of patient-reported health status at the time of admission to a general medicine inpatient service, and to determine the value of these new measures in predicting length of stay (LOS). Within 2 hours of the time that a decision to admit a patient was made, research assistants delivered a structured interview that captured patients' current symptoms, functional status, mood, and perceived health. Interviews were conducted between 8 a.m. and 11 p.m., 5 days per week from July 1996 through June 1997. During this time, there were 3621 unique patients admitted to the medicine service; 2672 (74%) of these patients were eligible for an interview. Eighty-eight percent of the 2672 eligible patients were interviewed. In addition to the patient-reported measures captured through the structured interview, the acute physiology score (APS) of the APACHE II was calculated for all subjects. The internal consistency (i.e., Cronbach's alpha) of the scales was 0.76 or greater and concurrent validity (i.e., correlation) of the patient-reported measures with the APS was 0.01 to 0.13. Overall perceived health was correlated 0.20 to 0.45 with symptoms and functional status, and was correlated 0.07 with the APS. The patient-reported measures performed comparably to the APS in predicting LOS (R-square = 0.08). When the patient-reported measures and the APS were included in the same model, the R-square was 0.14. These analyses suggest that patient-reported measures of health and function on admission hold validity, and that responses to as few as 15 questions can provide data that may help to explain differences in length of a hospital stay.

APACHE↗
PubMed1999

Physical activity and its correlates among urban primary care patients aged 55 years or older.

OBJECTIVES: Physical inactivity is a leading cause of death and disability, but very little is known about physical activity and its determinants among socially disadvantaged and medically vulnerable adults. The purpose of this study was to assess physical activity and its correlates, including measures of physical activity knowledge, perceived barriers, and self-efficacy, among socioeconomically disadvantaged older adults. METHODS: A stratified random sample of 1,088 patients aged 55 years or older was selected from an urban primary care center serving a predominantly low-income population. Of the 1,088 patients sampled, 771 (71%) completed an interviewer-administered questionnaire. RESULTS: A physical activity instrument, developed specifically for the population being studied, showed an average of 65 minutes of physical activity per week. Scores on a true-false knowledge quiz were no better than expected by chance, and over two thirds reported symptom and perceived environmental barriers to physical activity. Lower self-efficacy and greater symptom and motivational barriers were found to be associated with less physical activity. DISCUSSION: Given the prevalence of inactivity, knowledge deficits, and perceived barriers to physical activity, population-specific interventions may be required to improve rates of physical activity among socially disadvantaged and medically vulnerable adults.

Aged↗
PubMed1999

Development of a stroke-specific quality of life scale.

BACKGROUND AND PURPOSE: Clinical stroke trials are increasingly measuring patient-centered outcomes such as functional status and health-related quality of life (HRQOL). No stroke-specific HRQOL measure is currently available. This study presents the initial development of a valid, reliable, and responsive stroke-specific quality of life (SS-QOL) measure, for use in stroke trials. METHODS: Domains and items for the SS-QOL were developed from patient interviews. The SS-QOL, Short Form 36, Beck Depression Inventory, National Institutes of Health Stroke Scale, and Barthel Index were administered to patients 1 and 3 months after ischemic stroke. Items were eliminated with the use of standard psychometric criteria. Construct validity was assessed by comparing domain scores with similar domains of established measures. Domain responsiveness was assessed with standardized effect sizes. RESULTS: All 12 domains of the SS-QOL were unidimensional. In the final 49-item scale, all domains demonstrated excellent internal reliability (Cronbach's alpha values for each domain >/=0.73). Most domains were moderately correlated with similar domains of established outcome measures (r2 range, 0.3 to 0.5). Most domains were responsive to change (standardized effect sizes >0.4). One- and 3-month SS-QOL scores were associated with patients' self-report of HRQOL compared with before their stroke (P<0.001). CONCLUSIONS: The SS-QOL measures HRQOL, its primary underlying construct, in stroke patients. Preliminary results regarding the reliability, validity, and responsiveness of the SS-QOL are encouraging. Further studies in diverse stroke populations are needed.

Adult↗
PubMed1999

Exercise self-efficacy and its correlates among socioeconomically disadvantaged older adults.

Self-efficacy has been shown to be one of the strongest, mutable predictors of exercise behavior. This report presents data on exercise self-efficacy and outcome expectations and their correlates within a stratified random sample of 729 urban, lower-income primary-care patients age 55 and older. Exercise self-efficacy scores were greater among persons with current exercise, no pain of fear of shortness of breath with exercise, and good self-rated health. Higher outcome expectations scores were associated with verbal persuasion from a doctor or from family and friends and positive attitudes and knowledge of exercise. Sociodemographic characteristics, environmental factors, and intrapersonal factors accounted for 31% of the variance in self-efficacy, but just 13% of the variance in outcome expectations. Further work on potential correlates and their measurement is needed to identify determinants of both outcome expectations and self-efficacy.

Adult↗
PubMed1999

Correlates of physical activity in a sample of older adults with type 2 diabetes.

OBJECTIVE: Physical activity is integral to the management of type 2 diabetes. Unfortunately, the majority of adults with type 2 diabetes do not regularly engage in physical activity. The purpose of this study was to assess physical activity behavior and its correlates (i.e., physical activity knowledge, barriers, and performance and outcome expectations) in older adults with type 2 diabetes. RESEARCH DESIGN AND METHODS: A subgroup of 260 adults with type 2 diabetes was identified from a larger stratified random sample of adults aged > or = 55 years. Participants completed an interviewer-administered survey designed from focus group findings and social learning theory. RESULTS: The majority of the respondents (54.6%) reported 0 min of weekly physical activity. This was especially true of older female respondents. Performance expectation scores were lower among respondents who were in the oldest age-group, namely, white women. Physical activity knowledge varied by age-group, and barriers to physical activity were prevalent in all groups. The following are significant correlates of reported weekly physical activity: younger age, more education, fewer motivational barriers, and greater perceived health and performance expectations. CONCLUSIONS: Given the importance of physical activity to diabetes management, the low prevalence of physical activity found in this and other studies should raise concerns among clinicians. Future research to identify predictors of physical activity is needed to guide clinicians in the promotion of physical activity.

Black or African American↗
PubMed1998

Predictors of onset of and recovery from mobility difficulty among adults aged 51-61 years.

Relative to information on activities of daily living, information regarding the onset of and recovery from mobility difficulty has been limited. Drawing upon data gathered from 6,376 self-respondents aged 51-61 years at baseline (1992) who were successfully reinterviewed in 1994 as part of the Health and Retirement Survey, the authors were able to build upon and add to knowledge gained from previous studies of the onset of and recovery from mobility difficulty. Hierarchical logistic regression was used to separate the direct and indirect effects of predictors of mobility difficulty onset and recovery at 2-year follow-up. To separate direct and indirect effects, the authors categorized various predictors as being related to sociodemographic factors, economic factors, health behavior, chronic disease, or physical impairment, and the categories were sequentially incorporated into a series of equations. The order in which the predictors were incorporated into the equations followed from a theoretical model of the disability process. In this study of mobility difficulty, the strongest direct predictors of recovery were having little baseline difficulty and the absence of diabetes mellitus, lung disease, and frequent pain. The strongest direct predictors of onset were female sex, less education, low net worth, lack of private health insurance, obesity, and frequent pain. Few indirect predictors for either onset or recovery were identified. Predictors of recovery were few and differed from predictors of onset. Further efforts are needed to identify modifiable predictors among females, persons with few economic resources, and those with frequent pain.

Activities of Daily Living↗
PubMed1998

Predictors of mobility and basic ADL difficulty among adults aged 70 years and older.

We use data from the 1993-1995 Assets and Health Dynamics of the Oldest-Old survey to estimate predictors of onset of mobility difficulty, onset of basic activity of daily living (ADL) difficulty, and improvement to no mobility difficulty. Onset of mobility difficulty occurred among 20% of those with no difficulty at baseline (n = 2,857) and was most likely among those 85 years of age or over, women, those with a body-mass index of 30 or over, and those who reported lung disease, arthritis, frequent pain, and poor memory. For those with mobility difficulty at baseline (n = 1,871), improvement occurred among 24% and onset of basic ADL difficulty occurred among 25%. Improvement was more likely among those with difficulty in just one mobility item at baseline, and onset of ADL difficulty was most common among those with difficulty in three or more mobility items at baseline.

Activities of Daily Living↗
PubMed1997

Distribution and association of chronic disease and mobility difficulty across four body mass index categories of African-American women.

A majority of African-American women over the age of 50 are obese, have at least one chronic disease, and experience mobility difficulty. Using self-reported data from the 1992 Health and Retirement Study of 1,150 African-American women aged 30-70 years, this report first compares chronic disease prevalence and severity, pain, sensory deficits, and mobility difficulty across four categories of body mass index and, second, investigates whether body mass index affects the association of chronic disease with mobility difficulty. Body mass index was categorized as low, medium, high, and severe, being equal to 19-24 (20%), 25-29 (38%), 30-34 (24%), and 35 or over (18%), respectively. There were few differences when comparing the medium category with either the low or high category. Those in the severe body mass index category, however, reported significantly more frequent and severe hypertension, diabetes, cancer, heart disease, arthritis, pain, sensory deficits, and mobility difficulty than did those in the medium body mass index category. Obesity did not appear to affect the association between chronic disease and mobility difficulty. The relatively high rates of mobility difficulty observed among the severe body mass index group appear to be more likely a result of relatively high chronic disease prevalence and severity than to a disproportionate impact of these on mobility.

Activities of Daily Living↗
PubMed1997

Prevalence and impact of risk factors for lower body difficulty among Mexican Americans, African Americans, and whites.

BACKGROUND: The purpose of the study was to estimate the prevalence of sociodemographic, health behavior, chronic disease, and impairment factors and their impact on difficulty in lower body function among two age-cohorts (51-61 and 71-81 years) of Mexican Americans, African Americans, and Whites. METHODS: Reports from 8,727 and 4,510 self-respondents of the 1992 baseline Health and Retirement Survey and the 1993 baseline Assets and Health Dynamics Study, respectively, were used to estimate prevalence. Multiple linear regression of the 4-item lower body difficulty scale (alpha = .80) was used to estimate the direct effects of the risk factors within the age-cohort and ethnicity groups. RESULTS: Overall, the risk factors are more prevalent among both minority groups and the older age-cohort. Lower body deficits are particularly high among Mexican Americans and the younger age-cohort of African Americans. The impact of risk factors does not vary much by ethnicity or age-cohort. Female gender, pain, arthritis, and heart and lung disease are the major risk factors, and they account for about one-third of the variance in lower body difficulty for each group. CONCLUSIONS: Efforts to prevent or reduce lower body difficulty should pay particular attention to pain, arthritis, and heart and lung disease. The central role of sociodemographic and behavioral factors in chronic disease argues for their continued inclusion in disability modeling and prevention.

Black or African American↗
PubMed1997

The structure of health status among Hispanic, African American, and white older adults.

Activities of daily living (ADLs), instrumental ADLs, and disability markers have traditionally been the most common indicators of functional status. The study on Asset and Health Dynamics Among the Oldest Old (AHEAD) is used to replicate a five-dimensional measurement model composed of these observable indicators among the older adult self-respondents. The items available to measure upper body disability were found wanting, but the lower body disability, and the basic, household, and advanced ADL constructs were confirmed. Analyses of the measurement model separately among subgroups of women, men, Hispanics, Mexican Americans, African Americans, and Whites found no meaningful differences. Two structural models linking the lower body disability, and the basic, household, and advanced ADL constructs to perceived health and depression were also replicated among the older adult self-respondents, as well as separately among African Americans and among Whites. These models reaffirmed the dominant role of lower body disability on the everyday activities of older adults, and on their perceived health and depression.

Activities of Daily Living↗
PubMed1997

A race- and gender-specific replication of five dimensions of functional limitation and disability.

Activity of daily living (ADL) and instrumental ADL (IADL) data from the 1989 National Long-Term Care Survey (NLTCS) are used to replicate two domains of functional status with a total of five dimensions among them. LISREL analysis of the 14,415 Black and White older adults obtained from the 1989 NLTCS screen replicates three ADL disability dimensions (basic, household, and advanced) with few modifications, except among Black males. Similarly, analysis of the 4,297 Black and White disabled older adults replicates five functional status dimensions (3 ADL disability dimensions plus lower- and upper-body functional limitation dimensions) with few modifications, except among Black males. These results suggest that improved understanding of functional status will occur from studies that take into consideration the differences between functional limitation and ADL disability. The results also indicate that further research on the validity of functional reports among Black males is needed.

Activities of Daily Living↗
PubMed1997

US trends in disability and institutionalization among older Blacks and Whites.

OBJECTIVES: This study estimated and compared the prevalence of disability and institutionalization in 1982, 1984, and 1989 among the older Black and White populations of the United States. METHODS: Data on over 1100 Blacks and 14,000 Whites in each of a series of three National Long Term Care Surveys were used. RESULTS: Diverging trends for Blacks and Whites led to statistically significant increases in the age- and sex-adjusted odds of disability (19%) and institutionalization (31%) for Blacks relative to Whites. CONCLUSIONS: Black and White disparities in disability appear to have widened, while disparities in institutionalization appear to have narrowed during the decade of the 1980s.

Activities of Daily Living↗
PubMed1997

Physical activity efficacy and effectiveness among older adults and minorities.

The objective of this study was to consider efficacy and effectiveness of physical activity for the prevention and management of NIDDM among minorities and older adults of the U.S. Relevant population trends and projections are discussed, followed by a review of the efficacy of physical activity based on theoretical, prospective cohort, and intervention studies. With few empirical studies available, the assessment of effectiveness is largely theoretical and focuses on potentially important issues for future studies among older adults and minorities. Efficacy studies have shown that moderate-intensity physical activity is associated with a one- to two-thirds lower incidence of NIDDM over 4-14 years and 15-20% lower glycosylated hemoglobin over 3-4 months among people with NIDDM. With physical inactivity prevalence at 60-70%, much work remains to be done to improve physical activity effectiveness. In the most vulnerable populations, physician referral and community involvement structured around stage of change and self-efficacy theories are suggested as the most promising approaches to promoting physical activity adoption and maintenance. Effectiveness or demonstration studies that test and build on stage of change, self-efficacy, and other concepts of physical activity promotion and outcomes would likely prove to be highly valuable investments for public health.

Aged↗