Biomedical subjects

W Davidson

Publications and source records attributed to W Davidson.

At least 19 recordsLinked to original sources

PubMed2002

Estimation of total body water from bioelectrical impedance analysis in patients with pancreatic cancer -- agreement between three methods of prediction.

INTRODUCTION: Bioelectrical impedance analysis (BIA) is a useful field measure to estimate total body water (TBW). No prediction formulae have been developed or validated against a reference method in patients with pancreatic cancer. The aim of this study was to assess the agreement between three prediction equations for the estimation of TBW in cachectic patients with pancreatic cancer. METHODS: Resistance was measured at frequencies of 50 and 200 kHz in 18 outpatients (10 males and eight females, age 70.2 +/- 11.8 years) with pancreatic cancer from two tertiary Australian hospitals. Three published prediction formulae were used to calculate TBW - TBWs developed in surgical patients, TBWca-uw and TBWca-nw developed in underweight and normal weight patients with end-stage cancer. RESULTS: There was no significant difference in the TBW estimated by the three prediction equations - TBWs 32.9 +/- 8.3 L, TBWca-nw 36.3 +/- 7.4 L, TBWca-uw 34.6 +/- 7.6 L. At a population level, there is agreement between prediction of TBW in patients with pancreatic cancer estimated from the three equations. The best combination of low bias and narrow limits of agreement was observed when TBW was estimated from the equation developed in the underweight cancer patients relative to the normal weight cancer patients. When no established BIA prediction equation exists, practitioners should utilize an equation developed in a population with similar critical characteristics such as diagnosis, weight loss, body mass index and/or age. CONCLUSIONS: Further research is required to determine the accuracy of the BIA prediction technique against a reference method in patients with pancreatic cancer.

Aged↗

PubMed2001

Binding site elucidation of hydantoin-based antagonists of LFA-1 using multidisciplinary technologies: evidence for the allosteric inhibition of a protein--protein interaction.

The binding site on the lymphocyte function-associated antigen-1 (LFA-1) of a class of hydantoin-based antagonists of leukocyte cell adhesion has been identified. This site resides in the inserted-domain (I-domain) of the CD11a chain at a location that is distal to residues known to be required for interactions with the intercellular adhesion molecules. This finding supports the hypothesis that the molecules are antagonizing cell adhesion via an allosteric modification of LFA-1. The binding site was identified using an integrated immunochemical, chemical, and molecular modeling approach. Antibodies that map to epitopes on the I-domain were blocked from binding to the purified protein by the hydantoins, indicating that the hydantoin-binding site resides on the I-domain. Photoaffinity labeling of the I-domain followed by LC/MS and LC/MS/MS analysis of the enzymatic digest identified proline 281 as the primary amino acid residue covalently attached to the photoprobe. Distance constraints derived from this study coupled with known SAR considerations allowed for the construction of a molecular model of the I-domain/inhibitor complex. The atomic details of the protein/antagonist interaction were accurately predicted by this model, as subsequently confirmed by the X-ray crystal structure of the complex.

Allosteric Site↗

PubMed2001

Development of a standardized, comprehensive "ideal drug detail".

OBJECTIVES: To develop a standardized, comprehensive ideal drug detail for use in face-to-face education about individual drugs. METHODS: A random sample of 603 physicians and pharmacists was selected and stratified to include input from each of the following specialties: family practice, internal medicine, surgery, pediatrics, psychiatry, obstetrics/gynecology, geriatric medicine and clinical pharmacology. Thirty-one potential items were generated by the investigators from a preliminary survey of a local convenience sample of physicians and pharmacists. A modified Delphi consensus process was used in the large sample to determine which items should be included in the ideal drug detail. In each round of the Delphi process, respondents rated each item on a seven-point scale of importance and were then given feedback of the cumulative ratings for each item. Rounds were continued until consensus was obtained on all items. RESULTS: The response rate to the first round was 55.3%; 85.5% of these respondents responded to the second round. Response rates varied between specialties from 44% to 70%. Attempts to contact nonresponders to measure potential nonrespondent bias were unsuccessful. Consensus was obtained on 19 items after the first round, and on the remaining 12 items after the second round. Four items were dropped because they were unimportant. There was variation in modal response between specialties on eight items. CONCLUSIONS: Consensus was obtained among a sizable and interested sample of Canadian physicians and pharmacists on the items of information needed to prescribe a drug appropriately. Subsequent work will refine this list into a usable template to develop ideal drug details for specific drugs, to develop an assessment process to measure quality of information, and to assess the impact of this program on prescribing and patient outcomes.

Adult↗

PubMed2000

The corticobasal degeneration syndrome overlaps progressive aphasia and frontotemporal dementia.

OBJECTIVE: To provide evidence for the hypothesis that the corticobasal degeneration syndrome (CBDs) overlaps significantly with primary progressive aphasia and frontotemporal dementia, and that CBDs is part of the Pick complex. BACKGROUND: Corticobasal degeneration has been mainly described as a movement disorder, but cognitive impairment is also increasingly noted. METHODS: Thirty-five cases of clinically diagnosed CBDs were followed-up with clinical, neuropsychological, and neuroimaging investigations. Twenty-nine patients were seen prospectively in movement disorder and cognitive neurology clinics; five of these came to autopsy. Six other autopsied cases that fulfilled the clinical criteria of CBDs were added with retrospective review of records. RESULTS: All 15 patients presenting with movement disorders developed behavioral, cognitive, or language deficits shortly after onset or after several years. Patients presenting with cognitive problems (n = 20), progressive aphasia (n = 13), or frontotemporal dementia (n = 7) developed the movement disorder subsequently. Eleven cases with autopsy had CBD or other forms of the Pick complex. CONCLUSIONS: There is a clinical overlap between CBD, frontotemporal dementia, and primary progressive aphasia. There is also a pathologic overlap between these clinical syndromes. The recognition of this overlap will facilitate the diagnosis and avoid consideration of CBD as "heterogenous."

Aphasia↗

PubMed2000

Are there gender differences in starting protease inhibitors, HAART, and disease progression despite equal access to care?

OBJECTIVES: To describe gender differences in starting and response to treatment regimens and long-term clinical outcome in a well-characterized regional population from the Southern Alberta HIV Clinic (SAC) of 1403 patients, where all medical care for HIV, including physician fees, laboratory tests, and antiretroviral drug costs is provided free of charge. DESIGN: Observational cohort study. METHODS: Cox proportional hazards models were used to examine the relative risk of starting treatment regimens and disease progression (new AIDS-defining illness or death). RESULTS: There are 126 women in the SAC (9.0%). The median CD4 lymphocyte count at first visit among all patients was 350 cells/mm3, and was significantly higher among women than men (428 cells/mm3 versus 345 cells/mm3, respectively; p = 0.0024). Participating women were less well educated than participating men; 29% of women did not proceed beyond a tenth grade education compared with 13% of men; only 28% of women went to college or received a degree in contrast to 40% of men (p <. 001). The proportion of women in the cohort has increased over the past 5 years (p <.001). During a median follow-up period of 35 months that dates back as far as 1985, 572 patients (40.8%) died or progressed to a new AIDS-defining illness, of whom 30 were women (5. 2%). In a multivariate Cox model stratified by calendar quartile of first visit and adjusted for latest CD4, AIDS status, age, exposure group, education, and prior treatment, women were significantly less likely to start highly active antiretroviral therapy (HAART; defined as at least three antiretrovirals taken consecutively; relative hazard [RH], 0.69; 95% confidence interval [CI], 0.49-0.98; p =.033), significantly less likely to start a protease inhibitor containing treatment regimen (RH, 0.71; 95% CI, 0.52-0.98; p =.040) and significantly less likely to start a HAART regimen including a protease inhibitor (RH, 0.69; 95% CI, 0.48-1.00; p =.049). After adjustment for potentially confounding variables such as CD4 lymphocyte count and treatment regimen, no difference in disease progression was found between men and women (RH, 0.77; 95% CI, 0. 49-1.19; p =.24). Among patients who started HAART, the CD4 lymphocyte count and viral load at starting treatment regimens was similar between men and women, as were the immunologic and virologic response following initiation of treatment. CONCLUSIONS: Despite free access to antiretrovirals, women in the SAC were significantly less likely to start HAART treatment regimens, and the reasons for this need further investigation. Response to treatment was similar between genders. No evidence was found for a poorer long-term clinical outcome in women, but given the proven large clinical benefits of HAART, this may change in the future.

Adult↗

PubMed2000

Death the Fas way: regulation and pathophysiology of CD95 and its ligand.

Apoptotic cell death mediated by the members of the tumor necrosis factor receptor family is an essential process involved in the regulation of cellular homeostasis during development, differentiation, and pathophysiological conditions. Among the cell death receptors comprising the tumor necrosis factor receptor superfamily, CD95/APO-1 (Fas) is the best characterized. The specific interaction of Fas with its cognate ligand, Fas ligand (FasL), elicits the activation of a death-inducing caspase (cysteine aspartic acid proteases) cascade, occurring in a transcription-independent manner. Caspase activation executes the apoptosis process by cleaving various intracellular substrates, leading to genomic DNA fragmentation, cell membrane blebbing, and the exposure of phagocytosis signaling molecules on the cell surface. Recent studies have shown that the Fas/FasL pathway plays an important role in regulating the life and death of the immune system through activation-induced cell death. In addition, these molecules have been implicated in aging, human immunodeficiency virus infection, drug abuse, stress, and cancer development. In this review, we will focus on the mechanisms that regulate Fas and FasL expression, and how their deregulation leads to diseases.

Aging↗

PubMed2000

The Frontal Behavioral Inventory in the differential diagnosis of frontotemporal dementia.

A personality and behavioral disorder is an important and defining feature of frontal lobe dementia (FLD) or frontotemporal degeneration (FTD). The diagnosis usually depends on the progressive development of various behavioral symptoms rather than a set of neuropsychological measures. Quantification of the personality-behavior disorder is important for standardizing the diagnosis. An inventory was constructed to capture the major positive and negative behaviors and personality change, and it was administered prospectively to caregivers of 108 patients in a cognitive neurology clinic, at the time of first diagnostic assessment. The prevalence and extent of behavioral abnormality was quantitated in the clinic population of FLD, vascular dementia (VaD), Alzheimer's disease (AD), primary progressive aphasia (PPA), and depressive disorder (DD) patients. The mean scores of FLD patients were significantly above all other groups. Scores in VaD were also higher than in AD, PPA, and DD. Interrater reliability (Cohen's kappa of .90) and item consistency (a Cronbach alpha of .89) were both high. Perseveration, indifference, inattention, inappropriateness, and loss of insight rated highest in FLD, significantly different from all other groups. Apathy, aspontaneity, inflexibility, disorganization, impulsivity, personal neglect, and poor judgment were also significantly higher in FLD. Discriminant function correctly classified 92.7% versus all other patients (NON-FLD) in the study. A total of 18.8% of VaD patients were misclassified as FLD. Indifference, alien hand, and inappropriateness were the highest discriminant functions. Perseveration and verbal apraxia were important discriminatory items for FLD and PPA, respectively. The FBI is a standardized behavioral inventory useful to diagnose FLD, to differentiate it from other dementias, and to quantify the behavior disorder.

Aged↗

PubMed2000

B-cell receptor and Fas-mediated signals for life and death.

A series of B-cell lymphoma lines with an immature phenotype has been used as a model system to study molecular events associated with receptor ligation induced death. B-cell receptor (BCR) cross-linking with antibodies to membrane IgM (but not with anti IgD) induces c-Myc downregulation via nuclear factor kappaB inactivation and p27(Kip1) accumulation in these B lymphomas. Anti-mu-treated cells then undergo G1 arrest and die by apoptosis independent of Fas. Steroids and retinoids similarly downregulate c-Myc and induce apoptosis in these B cells and synergize with anti-mu. Rescue from apoptosis induced by anti-mu or steroids occurs with T-cell signals, like CD40L, or a broad-range caspase inhibitor, but only CD40L prevents the loss of c-Myc, p27 accumulation and growth arrest. Both IgM and IgD signaling lead to modulation of phosphatidylinositol 3-kinase (PI3K) signals, including the activation of p70(S6K), but this pathway recovers under anti-IgD treatment. Blockade of the PI3K pathway augments anti-mu-induced death and converts anti-delta to an apoptotic signal. Resistance to Fas-mediated death may be an important factor in B-cell transformation in vivo. Many of our panel of lymphomas are insensitive to Fas-mediated death signals, although all can form a death-inducing signaling complex (DISC). Additional studies suggest that some lymphomas can be blocked at the DISC complex by anti-apoptotic proteins, whereas others are inhibited downstream of caspase 8 activation. Anti-Ig treatment of a Fas-sensitive line, A20.2J, activated a number of genes whose products may block apoptosis proximally (like FLICE-inhibitory protein (FLIP1)) or at late points, such as bcl-2-family members. Our data suggest that B lymphomas develop multiple pathways of resistance to Fas-mediated signals during lymphomagenesis, in part via signaling through the BCR.

Animals↗

PubMed1999

Clinical and pathological overlap between frontotemporal dementia, primary progressive aphasia and corticobasal degeneration: the Pick complex.

A substantive overlap between the clinical syndromes of frontal lobe dementia (FLD), frontotemporal dementia (FTD), or primary progressive aphasia (PPA), and corticobasal degeneration syndrome (CBDS) has been demonstrated in a population of 55 patients followed for more than 3 years in a cognitive neurology clinic. Patients presenting with the personality behavior disorder (FLD) often develop progressive aphasia (PA) and vice versa. CBDS is often associated with FLD and PA, and the extrapyramidal-apractic syndrome of CBDS often appears in FLD and PPA. The histopathological variations do not predict the clinical phenotype. The term Pick complex is suggested to indicate that these clinical and pathological variations are related and they were first described by Pick as clinical manifestations of fronotemporal atrophy. This term will avoid the confusion of using FLD or FTD or for the whole complex and also for the personality behavioral presentation. The relationship of the various clinical presentations has been strengthened by the discovery of chromosome 17 linkage in families manifesting them.

Aphasia, Primary Progressive↗

PubMed1998

Predictors of a viral response and subsequent virological treatment failure in patients with HIV starting a protease inhibitor.

OBJECTIVES: To investigate the factors related to viral load becoming undetectable among patients from Southern Alberta who started a protease inhibitor for the first time, and to determine the factors related to subsequent re-emergence of detectable viral load amongst those patients whose viral load initially became undetectable. SUBJECTS AND METHODS: A total of 243 patients from the Southern Alberta Clinic had started a protease inhibitor for the first time and had been followed up for a median time of 32 weeks. Standard survival techniques including Kaplan-Meier techniques and Cox proportional hazards models were used to determine which factors were related to viral load becoming undetectable. RESULTS: At 24 weeks after first exposure to a protease inhibitor, 52.8% of the patients [95% confidence interval (Cl), 45.2-56.6] had achieved an undetectable viral load. In a multivariate analysis, those with a higher initial viral load were less likely to become undetectable [relative hazard (RH), 0.50; 95% Cl, 0.35-0.70; P < 0.0001], whereas those starting more new drugs (RH per new drug, 1.54; 95% Cl, 1.01-2.11; P = 0.048) were significantly more likely to achieve an undetectable viral load. Amongst 111 patients whose viral load became undetectable, Kaplan-Meier analysis indicated that 15.5% of patients experienced re-emergence of detectable viral load at 24 weeks after the first undetectable viral load. A higher CD4 cell count was associated with a lower risk of viral load becoming detectable (RH, 0.73; 95% Cl, 0.53-1.00; P = 0.049), as was treatment with indinavir (versus any other protease inhibitor RH, 0.17; 95% Cl, 0.03-0.86; P = 0.033). CONCLUSIONS: A significant proportion of patients in a routine clinic setting achieved an undetectable viral load measurement after first starting a protease inhibitor; viral load in patients with a higher CD4 cell count was more likely to become and stay undetectable. There was no evidence that patients who were drug-naive experienced significantly worse virological effects than drug-experienced patients, as long as the same number of new drugs was started at the date of first exposure to a protease inhibitor. Further follow-up of these patients is warranted to study the longer term effects of treatment with protease inhibitors.

Adult↗

PubMed1998

Prediction of axillary lymph node involvement of women with invasive breast carcinoma: a multivariate analysis.

BACKGROUND: The increasing use of systemic therapy for women with lymph node negative breast carcinoma and earlier stage of disease at mammographic detection raises questions regarding the need for routine axillary lymph node dissection. Predictive modeling for lymph node involvement may be one way to reduce the need for axillary lymph node dissection and its morbidity. METHODS: A multivariate analysis of 12 factors predictive of axillary lymph node involvement was conducted in a population-based cohort of 4312 women with invasive breast carcinoma diagnosed between January 1, 1993 and December 31, 1996. RESULTS: Clinical palpability, lymphatic or vascular invasion, lesion size, margin status, histology, and patient age were independent predictors of axillary lymph node involvement. The model correctly identified lymph node status in 76.6% of cases. Model accuracy and fit were equally high when applied to randomly selected halves of the study subjects. Approximately 32.0% of the patients in the study sample (1363/4312) were identified as having an extremely high (91%; n = 1102) or low (10%; n = 261) risk of lymph node involvement. In a second analysis, a clinically useable, three-variable model identified a very low risk group of patients (n = 147) with a 4.8% risk of lymph node metastasis and a high risk group of patients (n = 1008) with a 74.2% risk of lymph node metastasis. Greater than 90% of subjects in the high risk group received adjuvant systemic therapy even if they were lymph node negative pathologically. CONCLUSIONS: A clinically useable, three-variable model employing tumor and lymph node palpability, size, and lymphatic or vascular invasion can identify women with invasive breast carcinoma in whom axillary lymph node dissection is very unlikely to alter recommendations regarding adjuvant systemic therapy.

Adult↗

PubMed1998

A comparison of physiological responses and rating of perceived exertion between high-impact and low-impact aerobic dance sessions.

The aim of this study was to compare the exercise intensity and rating of perceived exertion (RPE) of a high-impact (HIP) and a low-impact (LIP) university aerobic dance session. Ten women [mean (SD) age 22.9 (2.6) years] took part in the study. An incremental treadmill test was performed by each subject to determine maximum oxygen consumption (VO2max) and maximum heart rate (HRmax). The measured VO2max [mean (SD)] was 49.0 (7.5) ml x kg(-1) x min(-1). The subjects were randomly assigned to LIP and HIP sessions (i.e. five of the subjects participated in the HIP session first, and the other five participated in the LIP session first). In a laboratory, heart rate, oxygen uptake and RPE were measured throughout each session for each subject. Expired air was collected continuously throughout the sessions using Douglas bags (ten bags over a 30-min period). The sessions consisted of 20 min of aerobic exercise (bags 1-7) followed by 5 min of local muscular endurance exercise (bags 8 and 9) and 5 min of flexibility exercises (bag 10). The mean intensity of the aerobic section of the LIP and HIP sessions was 51.6% and 64.7% VO2max, respectively. Ninety-five percent confidence intervals for the average difference between the HIP and LIP sessions demonstrate that the %VO2max was between 12% and 14% higher for the HIP session. The mean %HRmax for the LIP and HIP sessions was 71.4% and 76.7%, respectively, with the %HRmax in the HIP session being between 5.4% and 7.2% higher on average than that of the LIP session. On average, the RPE for the aerobic section of the HIP session (12.1) was consistently higher than that of the LIP session (11.1). HIP activity has the potential to maintain/improve the aerobic fitness of its participants. According to the literature, the exercise intensity elicited by LIP activity may have a limited training effect for the population utilised in this study, and for some individuals may result in detraining. Conversely, LIP activities may be an appropriate mode of exercise for overweight and unfit individuals.

Adolescent↗

PubMed1998

Primary progressive semantic aphasia: a case study.

A longitudinal case study of a patient with a progressive loss of meaning of objects with preserved phonology and syntax is presented. Repeated measures of language, praxis, visual cognition, and semantic processing were carried out. The patient still has preserved conversational speech, social skills, and orientation in her 8th year of her illness, but shows severe anomia and comprehension deficit in all modalities of stimulus presentation. In addition to standardized tests of language, cognition, and memory, specific experiments of categorization, modalities of word access, item consistency, category specificity, and definition of words were carried out. Results indicate a frequency dependent loss of meaning that was consistent in all modalities and throughout all object categories. However, the relative preservation of visual categorization of all categories tested and the language based categorization of animals suggested some fractionation of semantic memory. Relative preservation of autobiographical and personal memories versus semantic memory was a striking observation. Evidence for selective impairment of central semantic processing was obtained from experiments indicating item consistency of loss and the lack of semantic cuing. Neuroimaging evidence of left temporal lobe atrophy and the classical picture is compatible with similar cases published under the term semantic dementia or "transcortical sensory aphasia with visual agnosia" and suggest the diagnosis of Pick's disease.

Anomia↗

PubMed1997

Experiences from the structure determination of human cytomegalovirus protease.

Several obstacles were encountered and overcome during the structure determination of human cytomegalovirus protease. Dehydration of crystals, by exposing them to higher concentrations of the precipitant, reduced the mosaicity of the crystals and may have also resolved their microscopic twinning. The initial phase information was obtained with the selenomethionyl multiple-wavelength anomalous diffraction technique. However, site-specific mutagenesis was required to introduce extra Met residues into the protease. The phase information had to be improved by non-crystallographic symmetry averaging, initially among three 'crystal forms'. A change in the composition of the artificial mother liquor led to a significant improvement, from 3.0 and 2.0 A resolution, in the diffraction quality of the crystals. The experiences reported here may prove useful to structure determination of other proteins.

Journal Article↗

PubMed1997

Crystallization and preliminary crystallographic analysis of recombinant human P38 MAP kinase.

The recombinant human p38 MAP kinase has been expressed and purified from both Escherichia coli and SF9 cells, and has been crystallized in two forms by the hanging drop vapor diffusion method using PEG as precipitant. Both crystal forms belong to space group P2(1)2(1)2(1). The cell parameters for crystal form 1 are a = 65.2 A, b = 74.6 A and c = 78.1 A. Those for crystal form 2 are a = 58.3 A, b = 68.3 A and c = 87.9 A. Diffraction data to 2.0 A resolution have been collected on both forms.

Animals↗

PubMed1997

Frontal behavioral inventory: diagnostic criteria for frontal lobe dementia.

OBJECTIVE: To utilize the diagnostic criteria of frontal lobe dementia (FLD). METHODS: We studied 12 patients with FLD diagnosed clinically, with radiological confirmation in 10 and autopsy confirmation in 2; sixteen patients with Alzheimer's disease matched for stage and severity to FLD and 11 patients with depressive dementia were used as control groups. A 24-item Frontal Behavioral Inventory (FBI) using the most relevant behavioral manifestations of FLD was administered in these populations. RESULTS: FLD patient scores on the FBI were much higher compared with control groups (AD and DD). Item analysis showed loss of insight, indifference, distractibility, personal neglect and apathy as the most frequent negative symptoms. Perseveration, disinhibition, inappropriateness, impulsivity, and irresponsibility were the most significant positive symptoms. An operational definition of FLD included a minimum FBI score of 27. Only one false positive was shown in the depressive group and none among the AD group, indicating little overlap between patient groups, and a high discriminating value of the FBI. CONCLUSIONS: The FBI appears to be a useful diagnostic instrument and a method to operate the behavioral criteria of FLD. Further prospective studies are warranted to establish validity.

Aged↗

PubMed1996

National survey on the attitudes of Canadian physicians towards drug-detailing by pharmaceutical representatives.

OBJECTIVE: Our objective was to study the attitudes of Canadian physicians toward product presentations by pharmaceutical representatives (PRs), the use of inducements by the pharmaceutical industry, and methods to improve the quality of prescribing information provided to physicians. DESIGN: We used a mailed survey. PARTICIPANTS: A random sample of 550 Canadian physicians in all settings was chosen. OUTCOME MEASURES: The main outcome measure was the proportion of respondents agreeing with a series of statements. RESULTS: The response rate was 262 of 525 deliverable surveys (50 per cent). Respondents had a mean of 4.2 interactions per week with PRs. Of the 262 respondents (5.8 per cent of data were incomplete), 193 (80 per cent) believed that PRs overemphasize their products' effectiveness, 108 (45 per cent) thought PRs do not present fairly the drugs' negative aspects, and 223 (92 per cent) felt that PRs have production promotion as a goal. Most, 175 (70 per cent), believe that drug-detailing affects physicians' prescribing behavior. Most, 210 (86 per cent), considered drug samples acceptable, but fewer agreed that other inducements were acceptable. Of the respondents, 183 (74 per cent) agreed that PRs should be required to use guidelines for standardized, comprehensive drug-detailing, and 165 (65 per cent) agreed that face-to-face drug-detailing by PRs using standardized guidelines would be an effective way to receive information. CONCLUSIONS: There is dissatisfaction among Canadian physicians about the quality of information provided by the pharmaceutical industry. Standardized, comprehensive guidelines would be accepted by physicians as one improvement.

Advertising↗

PubMed1995

Physician characteristics and prescribing for elderly people in New Brunswick: relation to patient outcomes.

OBJECTIVE: To examine the relation between physician characteristics, prescribing behaviour and patient outcomes. DESIGN: Descriptive study linking four provincial databases. SETTING: New Brunswick. PARTICIPANTS: All 366 general practitioners (GPs) (accounting for 40% of all physicians with a general licence in New Brunswick) who ordered at least 200 prescriptions for elderly beneficiaries of the New Brunswick Prescription Drug Program and saw at least 20 elderly patients in an office setting between Apr. 1, 1990, and Mar. 31, 1991. Physicians with palliative care practices were excluded. OUTCOME MEASURES: GPs' personal, professional and practice characteristics, their prescribing patterns, and mortality, morbidity (number of days in hospital per patient) and hip-fracture rates among their elderly patients. RESULTS: Compared with the GPs who had a lower mortality rate, those with a higher mortality rate prescribed more drugs overall (p < 0.001), specifically antidepressants, bronchodilators, cholesterol-lowering agents, gastrointestinal drugs, neuroleptics and nonsteroidal anti-inflammatory drugs (NSAIDs). They also were more likely to be male (p < 0.01), had larger practices (p < 0.001), saw more patients per day (p < 0.05) and billed more per year (p < 0.001). Compared with the GPs who had a lower morbidity rate, those with a higher morbidity rate prescribed more drugs overall (p < 0.005), specifically bronchodilators, gastrointestinal drugs and NSAIDs. They also were more likely to be younger (p < 0.005) and male (p < 0.01), had fewer years in practice (p < 0.001), saw more patients per day (p < 0.05) and billed more per patient (p < 0.01). The GPs who had a higher hip-fracture rate prescribed more drugs overall (p < 0.001), notably antihypertensives, bronchodilators, cholesterol-lowering agents, gastrointestinal drugs and NSAIDs, than those who had a lower hip-fracture rate. They also had a larger practice (p < 0.001), practised more days per year (p < 0.005), had more patient visits per year (p < 0.05) and billed more per year (p < 0.001). Younger male GPs who practised with relatively more intensity and prescribed more drugs per patient had practices with higher morbidity, mortality and hip-fracture rates among their elderly patients than the other GPs. CONCLUSIONS: There is a significant relation between certain physician characteristics, their prescribing behaviour and patient outcomes. Further study is required to determine what physician characteristics and prescribing behaviours for specific illnesses contribute to patient outcomes. Regional differences should also be examined, as should incentives in this fee-for-service system. Linkage of these types of provincial databases may help in the evaluation of physicians' performance and in the development of strategic interventions and practice guidelines.

Adult↗