Biomedical subjects

Albin Leong

Publications and source records attributed to Albin Leong.

7 recordsLinked to original sources

PubMed2006

Validation of a beta-agonist long-term asthma control scale derived from computerized pharmacy data.

BACKGROUND: Asthma control has been defined clinically by using validated tools, but an asthma control scale using administrative data has not been reported. OBJECTIVE: We sought to validate a beta-agonist asthma control scale derived from administrative data. METHODS: Surveys that included validated asthma symptom and control tools were completed by a random sample of 2250 health maintenance organization members aged 18 to 56 years with persistent asthma. Linked computerized pharmacy data provided beta-agonist canister and oral corticosteroid dispensings. The proposed 4-level asthma control scale was based on the number of short-acting beta-agonist canisters dispensed in 12 months. Construct validity and predictive validity were assessed. RESULTS: For construct validity, factor analysis showed significant loading of the beta-agonist scale on the symptom control factor, and the beta-agonist scale was significantly related to the validated asthma control and symptom scales (r = 0.31, P < .0001). For predictive validity, each progressive level of the proposed beta-agonist control scale was associated with an increased risk of subsequent asthma hospitalizations or emergency department visits and oral corticosteroid use, independent of prior use. CONCLUSION: A scale based on the number of beta-agonists dispensed in a 1-year period and derived from administrative data reflects asthma symptom control over that period of time. This scale can help identify patients who are at risk for future acute asthma health care use. CLINICAL IMPLICATIONS: This information can be used in population management and by clinicians to assess long-term asthma control and identify patients who need intervention to prevent future morbidity.

Adolescent↗

PubMed2006

The controller-to-total asthma medication ratio is associated with patient-centered as well as utilization outcomes.

BACKGROUND: The ratio of controller medication to total asthma medications has been related to asthma utilization outcomes, but its relationship to patient-centered outcomes has not been explored. METHODS: Surveys that included validated asthma quality-of-life, control, and symptom severity tools were completed by a random sample of 2,250 health maintenance organization members aged 18 to 56 years who had persistent asthma. Linked computerized pharmacy data provided dispensing information on beta-agonist canisters and asthma controller medication. The ratio was calculated as the number of controller medications dispensed during the year of the survey divided by the total number medications (ie, inhaled beta-agonist plus controller medications) dispensed. The relationships of the optimal ratio cutoff to patient-centered outcomes and to subsequent acute asthma exacerbations were determined. RESULTS: Mean asthma quality-of-life, asthma control, and symptom severity scale scores were significantly (p < 0.0001) more favorable in patients with ratios of > or = 0.5. After adjusting for demographic characteristics, patients with ratios of > or = 0.5 were significantly less likely to have adverse results regarding asthma quality of life (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.52 to 0.80), asthma control (OR, 0.62; 95% CI, 0.50 to 0.77), and symptom severity (OR, 0.53; 95% CI, 0.43 to 0.65), and were also less likely to experience subsequent asthma hospitalizations or emergency department visits (OR, 0.44; 95% CI, 0.26 to 0.74) than patients with lower ratios. CONCLUSION: A higher controller medication/total asthma medication ratio is associated with better patient-centered asthma outcomes as well as with reduced emergency hospital utilization. This adds further support to the use of the medication ratio as an asthma quality-of-care measure.

Adrenal Cortex Hormones↗

PubMed2006

Development and validation of a medication intensity scale derived from computerized pharmacy data that predicts emergency hospital utilization for persistent asthma.

OBJECTIVE: To validate a risk stratification scheme using computerized pharmacy data to predict emergency hospital utilization for persistent asthma. STUDY DESIGN: Retrospective cohort. METHODS: The development sample consisted of 1079 HMO members aged 18 to 56 years with persistent asthma. The scale used medication cut-points as predictors for next-year emergency hospital utilization in a stepwise logistic regression model. Prediction properties were evaluated in a validation sample of 24 370 patients aged 18 to 56 years in a separate persistent-asthma database. RESULTS: Increasing use of beta-agonists (odds ratio [OR] of 2.2 for 5-13 vs 0-4 canisters; OR of 2.4 for >13 vs 5-13 canisters) and oral corticosteroids (OR of 2.6 for >2 vs 0-2 dispensing events) in the first year independently predicted emergency hospital utilization in the second year. Assigning 1 point for exceeding each of the above 3 medication thresholds led to a 4-level medication intensity scale that was significantly (P <.0001) related to validated measures of asthma symptom severity, asthma control, and asthma quality of life in the development sample. In the validation sample, this scheme identified a high-risk group that was 6 times more likely than the low-risk group to require subsequent emergency hospital care, with overall sensitivity of 65% and specificity of 54%. This scale did not perform as well as a scale based on both baseline emergency hospital care and pharmacy data. CONCLUSION: This simple risk stratification scheme can be used for populations with persistent asthma for whom computerized pharmacy data, but not computerized prior utilization data, are available.

Adolescent↗

PubMed2005

Improved asthma outcomes from allergy specialist care: a population-based cross-sectional analysis.

BACKGROUND: Prior studies suggest that allergist care improves asthma outcomes, but many of these studies have methodological shortcomings. OBJECTIVE: We sought to compare patient-based and medical utilization outcomes in randomly selected asthmatic patients cared for by allergists versus primary care providers. METHODS: A random sample of 3568 patients enrolled in a staff model health maintenance organization who were given diagnoses of persistent asthma completed surveys. Of these participants, 1679 (47.1%) identified a primary care provider as their regular source of asthma care, 884 (24.8%) identified an allergist, 693 (19.4%) reported no regular source of asthma care, and 195 (5.5%) identified a pulmonologist. Validated quality of life, control, severity, patient satisfaction, and self-management knowledge tools and linked administrative data that captured medication use were compared between groups, adjusting for demographics and baseline hospital and corticosteroid use. RESULTS: Compared with those followed by primary care providers, patients of allergists reported significantly higher (P < .001) generic physical and asthma-specific quality of life, less asthma control problems, less severe symptoms, higher satisfaction with care, and greater self-management knowledge. Patients of allergists were less likely than patients of primary care providers to require an asthma hospitalization (odds ratio, 0.45) or unscheduled visit (odds ratio, 0.71) and to overuse beta-agonists (odds ratio, 0.47) and were more likely to receive inhaled steroids (odds ratio, 1.81) during their past year. CONCLUSIONS: Allergist care is associated with a wide range of improved outcomes in asthmatic patients compared with care provided by primary care providers.

Adult↗

PubMed2005

Relationship of validated psychometric tools to subsequent medical utilization for asthma.

BACKGROUND: Risk stratification is used to identify patients with asthma at increased risk of experiencing morbidity and resource utilization. Validated psychometric tools are infrequently studied sources of data for this purpose. PURPOSE: To evaluate 4 types of validated psychometric tools as predictors for subsequent asthma utilization and determine their clinical usefulness. METHODS: Eleven hundred patients with active asthma from a Health Maintenance Organization completed surveys that included demographic information and validated psychometric tools measuring generic quality of life (physical and mental components), asthma-specific quality of life, asthma control, and asthma symptom severity. Survey records were linked to administrative data that captured emergency department and hospital care, short-acting beta-agonist, and oral corticosteroid utilization for the year of and the year following the survey. Relationships of survey variables with subsequent utilization were assessed, adjusting for both baseline demographic and asthma utilization factors. RESULTS: Scores of each psychometric tool were significantly related to subsequent utilization in univariate analyses and after adjusting for baseline utilization and demographic risk factors. Patients with higher scale-defined morbidity were as much as 4 times more likely to have subsequent utilization (sensitivity as high as 58%; specificity as high as 78%). Addition of an asthma-specific tool to either demographic or utilization prediction models added sensitivity (as much as 15%) but did not substantially improve the prediction properties of models containing both demographic and utilization predictors. CONCLUSION: Validated psychometric tools appear useful for asthma risk stratification in individuals and in populations in which both utilization and demographic predictors are not available.

Adolescent↗

PubMed2005

Relationships among quality of life, severity, and control measures in asthma: an evaluation using factor analysis.

BACKGROUND: Validated psychometric tools measuring quality of life, asthma control, and asthma severity have been developed, but their relationships with each other and with other important patient-centered outcomes have not been rigorously assessed. OBJECTIVE: To use factor analysis to evaluate the relationships of these validated tools with each other and with other patient-centered outcomes. METHODS: Surveys were completed by a random sample of 2854 Health Maintenance Organization members age 18 to 56 years with persistent asthma. Surveys included demographic information; validated tools measuring generic (Short Form-12; SF-12) and asthma-specific (Juniper Mini Asthma Quality of Life Questionnaire; AQLQ) quality of life, asthma control (Asthma Therapy Assessment Questionnaire), and asthma symptom severity (Asthma Outcomes Monitoring System); self-described severity, control, and course over time; and history of acute exacerbations. RESULTS: Principal component analysis suggested a 5-factor model that accounted for approximately 59% of the variability. The most prominent rotated factor reflected asthma symptom frequency (19.4% of variability), was measured by the symptom subscale of the AQLQ, and was the only factor significantly related to the Asthma Therapy Assessment Questionnaire, Asthma Outcomes Monitoring System, or the self-reported assessments of severity, control, or course. Other factors included symptom bother (12.1% of variability), reflected by the environment and emotion AQLQ subscales; activity limitation (13.9% of variability), reflected by the activity AQLQ subscale and the SF-12 physical component scale; mental health (8.3% of variability), reflected by the SF-12 mental component scale; and acute exacerbations (5.0% of variability), not measured by any of the validated scales. CONCLUSION: Distinct components of patient-reported asthma health status can be identified by factor analysis. Distinct constructs of severity versus control cannot be identified by the use of these tools alone.

Adolescent↗

PubMed2002

Studies of sick building syndrome. IV. Mycotoxicosis.

There has been increasing public attention to the potential health risks of mold exposure, particularly in wet buildings. A variety of molds has been isolated from both damaged homes and businesses, including agents that secrete toxigenic materials. One area that is attracting particular notice is the relative toxigenic potential of mycotoxins. Although exposure to molds can produce significant mucosal irritation, there are very few data to suggest long-term ill effects. More importantly, there is no evidence in humans that mold exposure leads to nonmucosal pathology. In fact, many of the data on toxigenic molds are derived from animal toxicity studies, and these are based primarily, on ingestion. Although every attempt should be made to improve the quality of indoor air, including avoidance of molds, the human illnesses attributed to fungal exposure are, with the exception of invasive infections and mold allergy, relatively rare. In this review we discuss selected aspects of the microbiology of mycotoxin-producing molds and their potential role in human immunopathology with respect to wet building environments.

Allergens↗