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Biomedical subjects

Arthur J Davidson

Publications and source records attributed to Arthur J Davidson.

18 recordsLinked to original sources

Durability of adherence to antiretroviral therapy on initial and subsequent regimens.

There is uncertainty regarding the durability of adherence to antiretroviral therapy. This study is a retrospective review of previously antiretroviral naïve patients initiating therapy between 1997 and 2002. Antiretroviral adherence was calculated using prescription refill data and was analyzed over time on an initial regimen and on sequential antiretroviral regimens. Three hundred forty-four patients were included. The median lengths of the first, second, and third regimens were stable at 1.7 years, 1.2 years, and 1.5 years, respectively (p = 0.10). In multivariate analysis the factor most significantly associated with earlier initial regimen termination was poor adherence. On an initial regimen, adherence decreased over time and declined most rapidly in patients with the shortest regimens (4 to <16 months, -43% per year), followed by patients with intermediate regimen duration (16 to <28 months, -19% per year), and then patients with longer regimens (>/=28 months, -5% per year). In patients progressing to a third regimen, there was a trend toward decreasing adherence over successive regimens. In conclusion, sequential antiretroviral regimens are of similar lengths, with adherence being highly associated with first regimen duration. Adherence decreases during an initial regimen and on sequential antiretroviral regimens. Effective and durable interventions to prevent declining adherence are needed.

Adult↗

Selective drug taking during combination antiretroviral therapy in an unselected clinic population.

OBJECTIVES: Multidrug therapy is necessary to achieve sustained viral suppression. Discordant adherence to individual components of a multidrug regimen may lead to adverse outcomes. METHODS: Antiretroviral-naive patients initiating therapy from 1997 through 2002 were included. Adherence for each antiretroviral was determined using pharmacy refill data. Selective drug taking was defined as > or =5% difference in adherence between 2 components of an antiretroviral regimen lasting at least 60 days. RESULTS: A total of 322 of 415 patients (78%) met inclusion criteria. Selective drug taking occurred in 47 of 322 patients (15%) and on 51 of 438 regimens (12%). Factors associated with selective drug taking were lower baseline CD4 lymphocyte count (adjusted odds ratio [AOR]: 1.3, 95% CI: 1.1 to 1.6 per 100 cell/microL decrease); 3 times daily dosing schedule (AOR: 4.1, 95% CI: 1.1 to 15.5); and the presence of significant adverse drug events (AOR: 2.9, 95% CI: 1.3 to 6.4). Regimens containing a fixed-dose combination dosage form were less likely to have selective drug taking (AOR: 0.5, 95% CI: 0.2 to 0.99). Outcomes independently associated with selective drug taking included earlier progression to a new AIDS-defining illness or death (hazard ratio: 2.3, 95% CI: 1.2 to 4.5). CONCLUSIONS: Selective drug taking was relatively common among patients taking combination antiretroviral therapy. The factor most closely associated with selective drug taking was the presence of an adverse drug event. Clinical outcomes appeared worse in patients with selective drug taking.

Adult↗

Factors that complicate the treatment of tuberculosis in HIV-infected patients.

Treatment of tuberculosis (TB) in persons coinfected with HIV has become increasingly complex during the past decade. We describe the factors that complicate anti-TB therapy in a large observational cohort of HIV-infected persons in the United States. Among 367 HIV-infected patients with 372 episodes of culture-confirmed TB, 44.1% had injection drug use as a mode of HIV transmission. Hepatic disease was present at the time of TB diagnosis or during anti-TB therapy for 91 episodes (24.5%). Elevation at least twice the upper limits of normal of aminotransaminases was observed during the first month of anti-TB therapy in 116 (31.2%) of the episodes. The most commonly reported adverse effects occurring during therapy were rash (27.8%), nausea (26.2%), leukopenia or neutropenia (20.2%), diarrhea (19.3%), vomiting (18.5%), and elevated temperature (>101.5 degrees F [38.6 degrees C], 16.9%). Prescription of a rifamycin and a medication known to interact with rifamycins occurred during 270 (72.6%) episodes. Because HIV-infected patients with TB often have underlying complicating conditions, such as hepatic disease, and are treated with medications that may have toxicities and cause drug-drug interactions, we recommend that clinicians pay careful attention to these factors when treating coinfected patients.

Antitubercular Agents↗

Antidepressant treatment improves adherence to antiretroviral therapy among depressed HIV-infected patients.

BACKGROUND: Antiretroviral regimens for HIV-infected patients require strict adherence. Untreated depression has been associated with medication nonadherence. We proposed to evaluate the effect of antidepressant treatment (ADT) on antiretroviral adherence. METHODS: Data were retrieved for HIV-infected patients seen at an urban health care setting (1997-2001) from chart review and administrative and pharmacy files. Antiretroviral adherence was determined for depressed patients stratified by receipt of and adherence to ADT. Antiretroviral adherence was compared before and after initiation of ADT. RESULTS: Of 1713 HIV-infected patients, 57% were depressed; of those, 46% and 52% received ADT and antiretroviral treatment, respectively. Antiretroviral adherence was lower among depressed patients not on ADT (vs. those on ADT; P = 0.012). Adherence to antiretroviral treatment was higher among patients adherent to ADT (vs. those nonadherent to antidepressant treatment; P = 0.0014). Antiretroviral adherence improved over a 6-month period for adherent, nonadherent, and nonprescribed ADT groups; however, the mean pre- versus post-6-month change in antiretroviral adherence was significantly greater for those prescribed antidepressants. CONCLUSIONS: Depression was common, and antiretroviral adherence was higher for depressed patients prescribed and adherent to ADT compared with those neither prescribed nor adherent to ADT. Attention to diagnosis and treatment of depressive disorders in this population may improve antiretroviral adherence and ultimate survival.

Adult↗

Strategies to improve immunization rates and well-child care in a disadvantaged population: a cluster randomized controlled trial.

OBJECTIVE: To measure the effect of a multimodal intervention on well-child care visit (WCV) and immunization rates in an inner-city population. DESIGN: Cluster randomized controlled trial. SETTING AND PARTICIPANTS: One-year cohort of 2843 infants born at a hospital in an integrated inner-city health care system. INTERVENTIONS: Eleven clinics were randomly allocated to 1 of 3 study arms: WCV intervention (n = 3), immunization intervention (n = 4), and controls (n = 4). Interventions to improve immunization and WCV rates included both patient-based and clinic-based activities. MAIN OUTCOME MEASURES: Up-to-date status with childhood immunizations and WCVs by age 12 months (primary) and health care utilization and charges (secondary). RESULTS: Compared with the control arm, the WCV and immunization arms had 5% to 6% higher immunization rates and 7% to 8% higher WCV rates. In multivariate analyses that accounted for the clustered nature of the data, the number of immunizations received was greater in the WCV arm than in controls. However, neither the WCV nor the immunization intervention increased WCV or immunization up-to-date rates. The WCV arm had slightly higher health care charges. Neither intervention affected emergency, urgent care or inpatient utilization. CONCLUSIONS: This multimodal intervention produced a small increase in the number of childhood immunizations delivered. However, patient- and clinic-based methods did not lead to significant increases in WCV or immunization up-to-date rates after controlling for other factors. Methods found in some settings to increase immunization up-to-date rates may not be as effective in a population of inner-city socioeconomically disadvantaged children.

Child Health Services↗

The case for interdepartmental research in primary care.

Research problems in human biology, clinical medicine, and health services delivery are complex, and increasingly require collaborative approaches. Despite the commitment of general internists, general pediatricians, and family physicians to comprehensive, coordinated, and longitudinal care, their substantial overlap in research topics, methods, and data sources, and their shared emphasis on research conducted in community-based settings, the three primary care disciplines rarely collaborate in research. The research enterprises of most primary care departments and divisions in the United States are small "cottage industries," while interdepartmental research units are rare. Interdepartmental research units can develop and maintain the critical mass of investigators, trainees, and staff that is necessary for an intellectually vibrant and financially sound primary care research enterprise. The University of Colorado Health Sciences Center School of Medicine has developed a successful interdepartmental research effort in primary care that includes joint fellowship training and faculty development programs and a Primary Care Research Unit that supports the analysis of secondary databases, practice-based research networks, and interdisciplinary research projects. Key elements of this collaboration include shared projects among faculty and trainees, proactive negotiation about resources, and shared research space, staff, and faculty. Such a collaboration provides the breadth of perspectives necessary to address complex health care problems, and the pragmatic infrastructure necessary to sustain research themes and careers.

Colorado↗

Self-reported health-related quality of life in persons with HIV infection: results from a multi-site interview project.

BACKGROUND: To examine demographic and behavioral associations with self-reported health-related quality of life (HRQOL) among persons with HIV infection or AIDS. METHODS: Analysis of interviews with persons > or = 18 years of age reported through routine disease surveillance with HIV infection or AIDS to nine state and local health departments from January 1995 through December 1996. Scales were constructed from validated measures of HRQOL, and mean scores were calculated (lower scores signified poorer HRQOL). Measures of HRQOL included Overall Health, Pain, Physical Functioning, Role Functioning, Social Functioning, Mental Health, Energy/Fatigue, and Cognitive Functioning. Differences in HRQOL were examined by various demographic and behavioral factors, including taking antiretroviral medication. RESULTS: HRQOL data were available for 3778 persons. Factors associated with lower HRQOL scores included older age, female sex, black or Hispanic race/ethnicity, injection drug use, lower education and income, no private health insurance, and lower CD4 count. In multivariate analysis, lower CD4 count was the factor most consistently associated with lower HRQOL. Taking antiretroviral medication was not associated with differences in HRQOL regardless of CD4 count. CONCLUSIONS: Perception of HRQOL varied in a population with HIV infection or AIDS. On most HRQOL measures, lower CD4 count was associated with lower HRQOL. Measurement of HRQOL can assist in understanding the long-term effects of disease and treatment on persons with HIV.

Adolescent↗

Immunization registry accuracy: improvement with progressive clinical application.

BACKGROUND: Healthcare systems have been challenged to ensure the timely administration of immunizations. Immunization registries have been proposed to improve the accuracy and completeness of immunization information and to promote effective practice. METHODS: Comparison of randomly selected samples from two birth cohorts (1993 and 1998) from Denver Health Medical Center. Chart review and immunization registry information for these groups were compared; a composite immunization was recorded and up-to-date (UTD) status established. Registry data were compared with this composite using a sensitivity measure to assess completeness and accuracy. RESULTS: Among 818 children in the 1993 cohort and 1043 children in the 1998 cohort, there were 6386 and 6886 valid immunizations, respectively. The registry recorded 71.4% and 97.7% of these for the 1993 and 1998 cohorts, respectively (p <0.001). The apparent UTD rate, as measured with registry data alone, improved from 37% to 79% between the two time frames (p <0.001). Composite UTD status was 83.1% and 78.9% (1993 vs 1998, respectively). Accurate registry-defined UTD status improved from 44.4% to 100% between the two intervals. CONCLUSIONS: Immunization registry accuracy improved dramatically for recorded immunizations and UTD status. However, after 3 years of registry use, the overall proportion of children who were UTD had not significantly improved. The mere presence of a registry does not ensure more complete vaccination coverage. Other registry-based strategies, including use of the data for reminder, recall, and audit, may further improve immunization coverage.

Child↗

Using respiratory-related calls to a nurse advice line to predict pediatric upper respiratory infection-related healthcare utilization.

Using Poisson regression analysis, respiratory-related calls to a nurse advice line in Denver, Colorado were used to predict pediatric upper respiratory infection (URI) outpatient and urgent care visits. Use of electronic hospital information systems and triage software allowed for the rapid identification of respiratory-related calls and URI-related utilization. Monitoring nurse advice line call volume may help increase awareness and planning for increases in healthcare utilization.

Colorado↗

Association between use of complementary/alternative medicine and health-related behaviors among health fair participants.

BACKGROUND: The relationship between complementary and alternative medicine (CAM) and standard preventive care is not well defined. METHODS: We surveyed 1,593 health fair participants on their use of CAM and determined odds ratios for standard preventive care and healthy behaviors among users of provider-based CAM (e.g., chiropractic) and users of herbs or supplements. RESULTS: Users of provider-based CAM were no less likely than nonusers to receive standard preventive care, with the exception of lower likelihood of influenza vaccination among elderly CAM users (OR 0.2). Herbs or supplements were used by a majority of respondents (61%), and users were more likely to report engaging in healthy behaviors such as eating a low-fat diet (OR 1.5) and taking a daily multivitamin (OR 2.0). CONCLUSIONS: Those who use alternative therapies, including herbs or supplements, appear no less likely overall than nonusers to receive standard preventive care. In addition, users of herbs or supplements are more likely to engage in healthy behaviors and appear to be a more health-conscious group. Overall, our findings support the notion that unconventional therapies are more complementary than alternative to standard preventive care.

Adolescent↗

Can paraprofessional home visitation enhance early intervention service delivery?

A 1-year randomized trial compared intensive case management (ICM) versus basic case management (BCM) in facilitating early intervention (EI) service use among children in an urban health system. Of 159 participating families with delayed or at-risk preschool-aged children, 88 received ICM from paraprofessionals versus 71 families who received less comprehensive BCM from a nurse. In the ICM versus BCM group, a shorter interval to assessment (98 vs 140 d, p =.05) but similar assessment rate (86% vs 80%, p =.29) was observed. The ICM group had more services recommended per child (1.64 vs 1.16, p < .004) and initiated (1.20 vs 0.85, p < .04). There was no difference in median time to EI program initiation for ICM versus BCM (228 vs 200 d, p = .88) or initiation and visit compliance rate for EI services. Specific efforts to improve outcomes (e.g., decrease initiation time and increase use of EI services) are still needed.

Age Factors↗

Epidemiology of pediatric injury-related primary care office visits in the United States.

OBJECTIVES: Unintentional injuries are a major cause of childhood mortality and morbidity in the United States. However, there is little epidemiologic information about pediatric injuries seen in primary care settings. The objective of this study was to characterize types and external causes of childhood injuries seen by primary care physicians and to compare the demographic and visit characteristics of children with injury-related visits (IRVs) and non-IRVs. METHODS: A stratified random sample survey of office-based practicing physicians in the National Ambulatory Medical Care Survey (1997 and 1998) was conducted. Injury-related primary care office visits were measured for patients who were <19 years (number of patient visits = 6358). RESULTS: Visits for childhood injuries composed >10 million primary care office visits per year (a rate of 13.8 visits per 100 person-years). The most common diagnoses assigned to these injuries were open wounds, sprains and strains, contusions, and superficial injuries such as abrasions and splinters. Leading external causes of these injuries were sports and overexertion, accidental falls, natural factors such as bites and stings, and cutting instruments. The single most common cause of pediatric injuries was sports/overexertion. Children who had IRVs were more likely to be older (odds ratio [OR]: 1.10/year of age; 95% confidence interval [CI]: 1.08-1.12), to be male (OR: 1.5; 95% CI: 1.2-1.9), and to reside in the West (OR: 1.9; 95% CI: 1.4-2.6) or in a rural area (OR: 1.4; 95% CI: 1.1-1.9). They were less likely to be Asian (OR: 0.2; 95% CI: 0.1-0.5) or Hispanic (OR: 0.5; 95% CI: 0.3-0.8). At the visit, children with IRVs were more likely to see a physician who was not their primary care physician (OR: 1.8; 95% CI: 1.4-2.3) and to see a family physician rather than a pediatrician (OR: 2.3; 95% CI: 1.8-2.9). CONCLUSIONS: IRVs account for a significant portion of primary care for children in the United States. Identifying potentially preventable external causes of injury and characteristics of children who are more likely to be injured is important both for injury prevention programs and for the education of physicians who care for children.

Adolescent↗

Individually significant risk factors do not provide an accurate clinical prediction rule for infant underimmunization in one disadvantaged urban area.

OBJECTIVE: To define a clinical prediction rule for underimmunization in children of low socioeconomic status. METHODS: We assessed a cohort of 1160 infants born from July 1998 through June 1999 at an urban safety net hospital that received primary care at 4 community health centers. The main outcome measure was up-to-date status with the 3:2:2:2 infant vaccine series at 12 months of age. RESULTS: Latino infants (n = 959, 83% of cohort) had immunization rates of 74%, at least 18% higher than any other racial/ethnic group. Multivariate logistic regression demonstrated the following independent associations (relative risk, 95% confidence interval) for inadequate immunization: non-Latino ethnicity (1.7, 1.4-2.0), maternal smoking (1.3, 1.1-1.7), no health insurance (1.9, 1.4-2.3), late prenatal care (1.9, 1.5-2.3), no pediatric chronic condition (2.1, 1.2-3.1), and no intent to breast-feed (1.3, 1.1-1.6). However, the index of concordance (c-index) for this model was only 0.69. Neither excluding infants who left the health care system nor accounting for infants who were "late starters" for their first vaccines improved the predictive accuracy of the model. CONCLUSIONS: In this predominantly Latino population of low socioeconomic status, Latino infants have higher immunization rates than other infants. However, we were unable to develop a model to reliably predict which infants in this population were underimmunized. Models to predict underimmunization should be tested in other settings. In this population, interventions to improve immunization rates must be targeted at all children without respect to individual risk factors.

Cohort Studies↗

The impact of inactive infants on clinic-based immunization rates.

OBJECTIVE: Clinic-based immunization rates are used to evaluate clinic performance and immunization interventions, but they typically exclude so-called inactive patients (ie, those who no longer receive care at the clinic). We assessed the effect of enhanced ascertainment of inactive patients on clinic-based immunization rates and on the conclusions of a randomized controlled trial. METHODS: The study was a post hoc analysis of a cluster-randomized controlled trial. Infant randomization to the immunization intervention (4 clinics) or control group (4 clinics) was based on the site of their 2-week well-child care visit. The study was conducted at an integrated inner-city health care system serving a low-income population. A total of 2190 infants born between July 1, 1998, and June 30, 1999, who attended at least 1 postnatal visit, participated. In control sites, clinic staff documented inactive infants in the immunization registry and medical charts. The research staff undertook additional patient tracking efforts in the intervention clinics. RESULTS: Control clinics identified 155 (13.4%) of 1160 children as inactive within 1 year of birth, whereas 284 (27.6%) of 1030 intervention infants were documented as inactive (P < .001). In bivariate analyses from the randomized trial, immunization rates differed between intervention and control branches. In multivariate models, immunization rates were significantly higher in the intervention branch when inactive infants were removed (adjusted relative risk 1.58; 95% confidence interval, 1.28-1.89), but not when they were included (adjusted relative risk 1.09; 95% confidence interval, 0.97-1.21). CONCLUSIONS: Additional patient tracking efforts can dramatically influence inactive patient documentation and clinic-based immunization rates used for various purposes.

Ambulatory Care Facilities↗

Less anticipatory guidance is associated with more subsequent injury visits among infants.

OBJECTIVE: To describe clinician delivery of injury prevention anticipatory guidance and injury visits in a birth cohort, and to describe the association of injury prevention anticipatory guidance with subsequent injury visits. METHODS: We performed a prospective cohort study of 2610 infants born from July 1, 1998 to June 30, 1999, at an urban safety-net hospital and seen subsequently for well child care (WCC, visits = 10558) and/or injury by 16 months of age. Injury guidance was defined as the proportion of recommended injury prevention anticipatory guidance items delivered to those expected, given the WCC visits the child attended. The outcome was a first injury visit to a clinic, emergency department, or hospital. RESULTS: The injury prevention items most discussed were car seats (84%-95% of all WCC visits) and rolling over at the 2-month WCC visit (80%). Other items were addressed at 36%-69% of visits. A total of 1931 (74%) of children received > or = 50% expected injury guidance. A total of 277 children (11%) had an injury visit, primarily for minor injuries. In unadjusted analysis, children receiving < 25% expected injury guidance were more likely to have a subsequent injury visit (unadjusted odds ratio 6.2; 95% confidence interval [95% CI] 3.2-9.7). In adjusted analysis, children who received < 25% and 25%-49% expected injury guidance were more likely to have a subsequent injury visits (adjusted odds ratio [AOR] 6.6; 95% CI 3.8-11.2; and AOR 2.9, 95% CI 2.0-4.3, respectively). CONCLUSIONS: Disadvantaged children whose families received less injury guidance than other children in their cohort were more likely to have a subsequent injury visit. Further studies are needed to determine whether increased injury prevention counseling reduces injury visits.

Accident Prevention↗

Podiatric problems are associated with worse health status in persons with severe mental illness.

The objective of this study was to determine the prevalence of self-reported podiatric impairments and their effect on health status in persons with severe mental illness. A sample of psychiatric outpatients (N=309) underwent interviews assessing medical conditions and health status with the Medical Outcomes Study Short Form-36 (SF-36). Podiatric health was assessed using nine items from the National Health Interview Survey (NHIS). Eighty percent of patients reported at least one podiatric problem. The most common problems were foot pain (48%), nail disorders (35%) and corns/calluses (28%). Prevalence rates were 4-11 times higher than those reported by the general population in the 1990 NHIS. The total number of podiatric problems was inversely related to eight self-reported health status domains and both summary SF-36 scores (all P<==.0001). After controlling for sociodemographic factors, psychiatric illness and medical conditions, the total number of podiatric limitations remained significantly associated with lower patient ratings in four of the eight SF-36 domains and both summary scores. We concluded that persons with severe and persistent mental illness have markedly elevated rates of podiatric problems when compared to the general population group. These problems are associated with worsened self-perceived health status. Addressing podiatric health may be a successful way to improve the overall health of this population.

Adolescent↗

Roundtable on bioterrorism detection: information system-based surveillance.

During the 2001 AMIA Annual Symposium, the Anesthesia, Critical Care, and Emergency Medicine Working Group hosted the Roundtable on Bioterrorism Detection. Sixty-four people attended the roundtable discussion, during which several researchers discussed public health surveillance systems designed to enhance early detection of bioterrorism events. These systems make secondary use of existing clinical, laboratory, paramedical, and pharmacy data or facilitate electronic case reporting by clinicians. This paper combines case reports of six existing systems with discussion of some common techniques and approaches. The purpose of the roundtable discussion was to foster communication among researchers and promote progress by 1) sharing information about systems, including origins, current capabilities, stages of deployment, and architectures; 2) sharing lessons learned during the development and implementation of systems; and 3) exploring cooperation projects, including the sharing of software and data. A mailing list server for these ongoing efforts may be found at http://bt.cirg.washington.edu.

Bioterrorism↗

Primary-care visits and hospitalizations for ambulatory-care-sensitive conditions in an inner-city health care system.

OBJECTIVE: Hospitalizations for ambulatory-care-sensitive conditions (ACSCs) are a marker for access barriers for children and a possible outcome measure for primary-care interventions. We assessed the relationship between primary-care utilization and subsequent ACSC hospitalization among inner-city children. METHODOLOGY: We conducted a nested, case-control study of children born in 1993 in Denver Health (DH), a "safety-net" delivery system in Denver, Colo. Utilization of preventive care and other primary-care services was compared between children hospitalized for ACSCs and nonhospitalized children, who were matched by age and duration of care. Comparisons were adjusted for demographics, payer, and chronic health conditions. RESULTS: Of 2531 children, 115 (4.5%) were hospitalized for ACSCs. Sixty-eight percent were Hispanic, and 78% were enrolled in Medicaid. Children with ACSC hospitalization and nonhospitalized children made a similar number of preventive-care visits (2.7 +/- 2.0 vs 3.0 +/- 2.1 visits, P =.30) and other primary-care visits (4.4 +/- 4.6 vs 3.6 +/- 4.6, P =.16) between birth and hospitalization (for cases) or the same time period (for controls). After multivariate adjustment, each additional preventive-care visit (odds ratio = 0.87; 95% confidence interval: 0.67-1.12) was associated with a nonsignificant reduction in the risk of hospitalization for ACSC. CONCLUSIONS: Because ACSC hospitalizations are uncommon and the association between primary care and subsequent hospitalization is weak, a reduction in ACSC hospitalizations may not be a feasible outcome measure for interventions to increase the rate of preventive- or primary-care visits for underserved children within individual delivery systems.

Ambulatory Care↗