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C David Naylor

Publications and source records attributed to C David Naylor.

36 records · Page 2Linked to original sources
PubMed2003

Burden of parkinsonism: a population-based study.

Parkinson's disease (PD) is associated with a significant burden of illness and cost to society, which has been difficult to quantify. Our objective was to use linked administrative databases from the population of Ontario, Canada, to assess the prevalence of parkinsonism, physician- and drug-related costs, and hospital utilization for parkinsonian patients compared with age/sex matched controls. An inception cohort of parkinsonian cases from 1993/1994 was age and sex matched (1:2) to controls and followed for 6 years. Patients were identified by the diagnostic code for PD, the use of specific PD drugs, or a combination. The parkinsonian case cohort (15,304) was matched to (30,608) controls that did not have parkinsonism. The age-adjusted prevalence rates were 3.63 for men and for 3.24 women per 1,000 (increased by 5.4% for men and 9.8% for women). Physician costs were 1.4 times more, there were 1.44 times more hospital admissions, admissions were on average 1.19 times longer, and drug costs were 3.0 times more for parkinsonian cases. We conclude that the substantially higher physician and drug costs as well as hospitalization rates compared with controls clearly suggest that parkinsonism is associated with large direct costs to society.

Adult↗
PubMed2002

Accelerated publication versus usual publication in 2 leading medical journals.

BACKGROUND: A number of medical journals have developed policies for accelerated publication of articles judged by the authors, the editors or the peer reviewers to be of special importance. However, the validity of these judgements is unknown. We therefore compared the importance of articles published on a "fast track" with those published in the usual way. METHODS: We identified 12 "case" articles--6 articles from the New England Journal of Medicine that were prereleased on the journal's Web site before publication in print and 6 "fast-tracked" articles from The Lancet. We then identified 12 "control" articles matched to the case articles according to journal, disease or procedure of focus, theme area and year of publication. Forty-two general internists rated the articles, using 10-point scales, on dimensions addressing the articles' importance, ease of applicability and impact on health outcomes. RESULTS: For each dimension, the mean score for the case articles was significantly higher than the mean score for the control articles: importance to clinical practice 7.6 v. 7.1 respectively (p = 0.001), importance from a public health perspective 6.5 v. 6.0 (p < 0.001), contribution to advancement of medical knowledge 6.2 v. 5.8 (p < 0.001), ease of applicability in practice 7.0 v. 6.5 (p < 0.001), potential impact on health outcomes 6.5 v. 5.9 (p < 0.001). Despite these general findings, in 5 of the 12 matched pairs of articles the control article had a higher mean score than the case article across all the dimensions. INTERPRETATION: The accelerated publication practices of 2 leading medical journals targeted articles that, on average, had slightly higher importance scores than similar articles published in the usual way. However, our finding of higher importance scores for control articles in 5 of the 12 matched pairs shows that current journal practices for selecting articles for expedited publication are inconsistent.

Diffusion of Innovation↗
PubMed2002

Using disease risk estimates to guide risk factor interventions: field test of a patient workbook for self-assessing coronary risk.

OBJECTIVE: To assess the feasibility and acceptability of a patient workbook for self-assessing coronary risk. DESIGN: Pilot study, with post-study physician and patient interviews. SETTING AND SUBJECTS: Twenty southern Ontario family doctors and 40 patients for whom they would have used the workbook under normal practice conditions. INTERVENTIONS: The study involved convening two sequential groups of family physicians: the first (n=10) attended focus group meetings to help develop the workbook (using algorithms from the Framingham Heart Study); the second (n=20) used the workbook in practice with 40 patients. Follow-up interviews were by interviewer-administered questionnaire. MAIN OUTCOMES MEASURES: Physicians' and patients' opinions of the workbook's format, content, helpfulness, feasibility, and potential for broad application, as well as patients' perceived 10-year risk of a coronary event measured before and after using the workbook. RESULTS: It took an average of 18 minutes of physician time to use the workbook: roughly 7 minutes to introduce it to patients, and about 11 minutes to discuss the results. Assessments of the workbook were generally favourable. Most patients were able to complete it on their own (78%), felt they had learned something (80%) and were willing to recommend it to someone else (98%). Similarly, 19 of 20 physicians found it helpful and would use it in practice with an average of 18% of their patients (range: 1-80%). The workbook helped to correct misperceptions patients had about their personal risk of a coronary event over the next 10 years (pre-workbook (mean (SD) %): 35.2 (16.9) vs. post-workbook: 17.3 (13.5), P < 0.0001; estimate according to algorithm: 10.6 (7.6)). CONCLUSIONS: Given a simple tool, patients can and will assess their own risk of CHD. Such tools could help inform otherwise healthy individuals that their risk is increased, allowing them to make more informed decisions about their behaviours and treatment.

Adult↗
PubMed2002

Development and prognosis of non-Q-wave myocardial infarction in the thrombolytic era.

BACKGROUND: Data on non-Q myocardial infarctions (MI) are derived primarily from prethrombolytic era studies. Previous trials demonstrated different development rates and none reported on clinical outcomes. METHODS: Our goal was to determine the incidence and prognosis of non-Q-wave MI among patients with ST-segment elevation receiving thrombolysis. A retrospective analysis of 5 randomized controlled trials was made. The main outcome measures included rates of (1) transformation of ST-segment elevation to Q- and non-Q-wave MI and (2) inhospital and 1-year mortality and reinfarction among patients who subsequently develop a Q or non-Q MI postthrombolysis as compared to controls. RESULTS: Non-Q wave development was greater among patients receiving thrombolysis versus placebo/control (3.1% absolute difference, 95% CI 1.2%-5.0%). Among patients receiving thrombolysis, those who developed a non-Q MI experienced significantly lower inhospital and 1-year mortality (absolute differences -3.8% [95% CI -5.2% to -2.4%] and -6.4% [95% CI -9.9% to -3.0%], respectively) and reinfarction (absolute differences -2.9% [95% CI -4.3% to -1.6%] and -3.5% [95% CI -6.1% to -0.9%], respectively) rates, compared with those who evolved a Q MI. Inhospital and 1-year mortality was also significantly lower when compared to placebo/control patients who developed a non-Q MI (absolute differences 4.6% [95% CI -8.2% to -1.1%] and -7.5% [95% CI -12.5% to -2.5%], respectively). CONCLUSIONS: Patients receiving thrombolysis more often develop a non-Q-wave MI and have a better prognosis than either those who develop a Q MI postthrombolysis or a non-Q MI after standard medical therapy.

Electrocardiography↗
PubMed2002

The relevance of subgroup-specific treatment effects: the Studies Of Left Ventricular Dysfunction (SOLVD) revisited.

BACKGROUND: The overall effect sizes estimated from randomized clinical trials may not apply similarly to all patients. Univariate subgroup analyses are often used to help determine the generalizability of a trial's results, but may themselves be misleading. We reanalyzed the Studies of Left Ventricular Dysfunction (SOLVD) to determine whether the treatment effect depended on the patients' baseline prognosis, defined on the basis of multiple clinical variables. METHODS: The SOLVD prevention (4228 patients) and the SOLVD treatment (2569 patients) trials were randomized, double-blind trials that studied the effect of enalapril in patients with reduced left-ventricular function or congestive heart failure. We combined both SOLVD populations and compared the results of a univariate analysis to a multivariate approach in which 3 patient subgroups were defined according to baseline risks for the combined end point of death or hospitalization for heart failure. RESULTS: Enalapril treatment resulted in 24% fewer events. The strongest predictors of an event were ejection fraction, New York Heart Association classification and age, antiplatelet agents, history of diabetes mellitus, treatment with digoxin or diuretics, and race. Only ejection fraction produced a significant treatment interaction (P =.004). Consistent with the original SOLVD reports, this interaction was also demonstrable when ejection fraction was scaled into tertiles and examined on its own (P =.012). However, there was no interaction present when patients were divided into tertiles of multifactorial baseline risk. CONCLUSIONS: We confirmed the treatment effect of enalapril, the impact of left-ventricular systolic function, and the negative prognostic importance of diabetes mellitus in this population. Although ejection fraction led to a subgroup-treatment interaction in the main SOLVD publications, a multifactorial approach to prognostic grouping abolished the interaction. These findings highlight the limitations of univariate subgroup analyses and illustrate that multivariate risk group analysis may be a complementary method for assessing the generalizability of the overall treatment effects observed in randomized trials.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2002

Factoring socioeconomic status into cardiac performance profiling for hospitals: does it matter?

BACKGROUND: Critics of "scorecard medicine" often highlight the incompleteness of risk-adjustment methods used when accounting for baseline patient differences. Although socioeconomic status is a highly important determinant of adverse outcome for patients admitted to the hospital with acute myocardial infarction, it has not been used in most risk-adjustment models for cardiovascular report cards. OBJECTIVES: To determine the incremental impact of socioeconomic status adjustments on age, sex, and illness severity for hospital-specific 30-day mortality rates after acute myocardial infarction. METHODS: The authors compared the absolute and relative hospital-specific 30-day acute myocardial infarction mortality rates in 169 hospitals throughout Ontario between April 1, 1994 and March 31, 1997. Patient socioeconomic status was characterized by median neighborhood income using postal codes and 1996 Canadian census data. They examined two risk-adjustment models: the first adjusted for age, sex, and illness severity (standard), whereas the second adjusted for age, sex, illness severity, and median neighborhood income level (socioeconomic status). RESULTS: There was an extremely strong correlation between 'standard' and 'socioeconomic status' risk-adjusted mortality rates (r = 0.99). Absolute differences in 30-day risk-adjusted mortality rates between the socioeconomic status and standard risk-adjustment models were small (median, 0.1%; 25th-75th percentile, 0.1-0.2). The agreement in the quintile rankings of hospitals between the socioeconomic status and standard risk-adjustment models was high (weighted kappa = 0.93). CONCLUSION: Despite its importance as a determinant of patient outcomes, the effect of socioeconomic status on hospital-specific mortality rates over and above standard risk-adjustment methods for acute myocardial infarction hospital profiling in Ontario was negligible.

Age Factors↗
PubMed2002

Healthy-year equivalents in major joint replacement. Can patients provide meaningful responses?

OBJECTIVES: Healthy-years equivalents (HYEs) have been proposed as an evaluative measure with advantages over quality-adjusted life-years (QALYs). The main purpose was to assess the feasibility of eliciting HYEs from patients who have undergone major joint replacement; a secondary objective was to examine relationships with postsurgical health status. METHODS: Pre- and postsurgical reports of perceived comorbidity and current arthritic burden were obtained from 194 patients, using a comorbidity checklist, summary scores from the Western Ontario/McMaster Osteoarthritis Questionnaire (WOMAC), summary scores derived from six Likert scales, and holistic utility scores for the same attributes. After surgery, HYEs for the full across-time health profile were also elicited. RESULTS: All measures of arthritic burden were sensitive to pre/postsurgical changes (p = .0001), and comorbidity scores were stable. Two HYE subgroups emerged. An HYE-invariant subgroup ascribed full HYEs to their profiles, while reporting higher Likert (t = 2.1309; p = .0344) and utility (s = 4.1504; p = .0001) scores for their postsurgical health state. An HYE-variant subgroup reported HYEs that were weakly but significantly (p < .009) correlated with Likert (r = .30), utility (rs = .25), and comorbidity (r = -.26) scores for their postsurgical state. CONCLUSIONS: Our results indicate that patients can understand the HYE assessment procedures and provide interpretable responses. However, a significant proportion reports invariant HYEs that could inflate estimates of the overall mean HYE. Further exploration of the HYEs reported by different clinical and attitudinal populations is needed before widespread adoption of this measure.

Adult↗
PubMedDate not supplied

Primary prevention drug therapy: can it meet patients' requirements for reduced risk?

The objective was to identify, in primary prevention, patients whose "required risk reduction" (ReqRR) is greater than the "achievable risk reduction" (ARR) that cholesterol-lowering or antihypertensive medication could provide. Individualized estimates of 10-year coronary heart disease or stroke risk were derived for 66 hypercholesterolemic (HC) and 64 hypertensive (HT) patients without symptomatic cardiovascular disease. These estimates were used in trade-off tasks identifying each individual's ReqRR. Then individual ARRs were estimated (in HC patients by assuming total cholesterol/high density lipoprotein ratio reductions to 5.0; in HT patients by assuming systolic blood pressure reductions to 120 mmHg). 12 (18%) HC and 12 (19%) HT subjects would refuse medication regardless of the risk reduction offered. Of the remaining patients, 15/54 (28%; 95% C.I.:16-40%) HC and 19/52 (37%; 95% C.I: 24-51%) HT subjects were "over-requirers," in that their ReqRR/ARR ratio was 1.5. There maybe a notable proportion of patients whose ReqRR is considerably greater than what is achievable, implying that decision aids may help individuals clarify preferences about accepting/refusing medication for the primary prevention of cardiovascular disease.

Adult↗
PubMedDate not supplied

Leadership in academic medicine: reflections from administrative exile.

Physicians are drawn into diverse leadership roles in academic medicine, but little in our education and training prepares us for these responsibilities. Fortunately, there is growing convergence in the literature on the attributes of successful leaders for knowledge-based organisations. Top-performing leaders seem to be self-effacing team-builders who eschew rapid-cycle strategic planning and management trends, focusing instead on strategic and incremental changes that will gradually transform their organisations. Academic physicians and search committees often concentrate on personal achievement and intellectual or technical mastery in research and clinical care. In contrast, the literature on leadership suggests other-directed skills matter more, eg mentorship, learning and teaching competencies, and so-called emotional intelligence. As a corollary, teaching hospitals, universities, and professional colleges or societies are long-term organisations with a rich history. Leadership in such a context demands stewardship of tradition along with patient pursuit of changes required to ensure that the organisation evolves successfully.

Academic Medical Centers↗