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William A Ghali

Publications and source records attributed to William A Ghali.

At least 19 recordsLinked to original sources
PubMed2006

Dealing with missing data in a multi-question depression scale: a comparison of imputation methods.

BACKGROUND: Missing data present a challenge to many research projects. The problem is often pronounced in studies utilizing self-report scales, and literature addressing different strategies for dealing with missing data in such circumstances is scarce. The objective of this study was to compare six different imputation techniques for dealing with missing data in the Zung Self-reported Depression scale (SDS). METHODS: 1580 participants from a surgical outcomes study completed the SDS. The SDS is a 20 question scale that respondents complete by circling a value of 1 to 4 for each question. The sum of the responses is calculated and respondents are classified as exhibiting depressive symptoms when their total score is over 40. Missing values were simulated by randomly selecting questions whose values were then deleted (a missing completely at random simulation). Additionally, a missing at random and missing not at random simulation were completed. Six imputation methods were then considered; 1) multiple imputation, 2) single regression, 3) individual mean, 4) overall mean, 5) participant's preceding response, and 6) random selection of a value from 1 to 4. For each method, the imputed mean SDS score and standard deviation were compared to the population statistics. The Spearman correlation coefficient, percent misclassified and the Kappa statistic were also calculated. RESULTS: When 10% of values are missing, all the imputation methods except random selection produce Kappa statistics greater than 0.80 indicating 'near perfect' agreement. MI produces the most valid imputed values with a high Kappa statistic (0.89), although both single regression and individual mean imputation also produced favorable results. As the percent of missing information increased to 30%, or when unbalanced missing data were introduced, MI maintained a high Kappa statistic. The individual mean and single regression method produced Kappas in the 'substantial agreement' range (0.76 and 0.74 respectively). CONCLUSION: Multiple imputation is the most accurate method for dealing with missing data in most of the missind data scenarios we assessed for the SDS. Imputing the individual's mean is also an appropriate and simple method for dealing with missing data that may be more interpretable to the majority of medical readers. Researchers should consider conducting methodological assessments such as this one when confronted with missing data. The optimal method should balance validity, ease of interpretability for readers, and analysis expertise of the research team.

Alberta↗
PubMed2006

Association of socio-economic status with diabetes prevalence and utilization of diabetes care services.

BACKGROUND: Low income appears to be associated with a higher prevalence of diabetes and diabetes related complications, however, little is known about how income influences access to diabetes care. The objective of the present study was to determine whether income is associated with referral to a diabetes centre within a universal health care system. METHODS: Data on referral for diabetes care, diabetes prevalence and median household income were obtained from a regional Diabetes Education Centre (DEC) database, the Canadian National Diabetes Surveillance System (NDSS) and the 2001 Canadian Census respectively. Diabetes rate per capita, referral rate per capita and proportion with diabetes referred was determined for census dissemination areas. We used Chi square analyses to determine if diabetes prevalence or population rates of referral differed across income quintiles, and Poisson regression to model diabetes rate and referral rate in relation to income while controlling for education and age. RESULTS: There was a significant gradient in both diabetes prevalence (chi2 = 743.72, p < 0.0005) and population rates of referral (chi2 = 168.435, p < 0.0005) across income quintiles, with the lowest income quintiles having the highest rates of diabetes and referral to the DEC. Referral rate among those with diabetes, however, was uniform across income quintiles. Controlling for age and education, Poisson regression models confirmed a significant socio-economic gradient in diabetes prevalence and population rates of referral. CONCLUSION: Low income is associated with a higher prevalence of diabetes and a higher population rate of referral to this regional DEC. After accounting for diabetes prevalence, however, the equal proportions referred to the DEC across income groups suggest that there is no access bias based on income.

Alberta↗
PubMed2006

The prognostic importance of nonsignificant left main coronary artery disease in patients undergoing percutaneous coronary intervention.

OBJECTIVES: The purpose of this research was to study the association between nonsignificant (<50%) left main coronary artery disease (LMCAD) and short- and long-term survival in patients undergoing percutaneous coronary intervention (PCI). BACKGROUND: The prognostic importance of nonsignificant LMCAD is unknown; however, the co-existence of nonsignificant LMCAD may influence revascularization decisions. METHODS: We analyzed mortality and repeat catheterization rates of 11,855 patients in a prospective cardiac registry database who underwent single-vessel or multivessel PCI from January 1996 through December 2001. Of this cohort, 11.7% (n = 1,385) had nonsignificant (<50%) LMCAD. Outcomes were compared with those without LMCAD. A secondary analysis was performed on a larger cohort of 34,586 patients undergoing cardiac catheterization, irrespective of mode of revascularization therapy. RESULTS: Patients with nonsignificant LMCAD had more co-morbidities, and a significantly higher crude mortality rate at 1 year compared with those without LMCAD (4.4% vs. 3.4%; p = 0.05). The 7-year crude mortality hazard ratio (HR) of PCI patients with <50% LMCAD versus those with no LMCAD was 1.18 (95% confidence interval [CI] 0.94 to 1.46). After risk adjustment for differences in baseline clinical profile, however, the HR decreased to 0.98 (95% CI 0.79 to 1.23). Repeat catheterization rates at 1 year did not differ between groups. The secondary analysis in all patients with nonsignificant LMCAD showed an adjusted HR of 1.03 (95% CI 0.94 to 1.14). CONCLUSIONS: Patients undergoing single-vessel or multivessel PCI who have <50% LMCAD have a nonsignificantly increased 18% relative risk for mortality compared with those without detectable LMCAD that appears to be related to these patients' higher incidence of co-morbidities rather than the left main stenosis itself.

Aged↗
PubMed2006

Identifying priorities in methodological research using ICD-9-CM and ICD-10 administrative data: report from an international consortium.

BACKGROUND: Health administrative data are frequently used for health services and population health research. Comparative research using these data has been facilitated by the use of a standard system for coding diagnoses, the International Classification of Diseases (ICD). Research using the data must deal with data quality and validity limitations which arise because the data are not created for research purposes. This paper presents a list of high-priority methodological areas for researchers using health administrative data. METHODS: A group of researchers and users of health administrative data from Canada, the United States, Switzerland, Australia, China and the United Kingdom came together in June 2005 in Banff, Canada to discuss and identify high-priority methodological research areas. The generation of ideas for research focussed not only on matters relating to the use of administrative data in health services and population health research, but also on the challenges created in transitioning from ICD-9 to ICD-10. After the brain-storming session, voting took place to rank-order the suggested projects. Participants were asked to rate the importance of each project from 1 (low priority) to 10 (high priority). Average ranks were computed to prioritise the projects. RESULTS: Thirteen potential areas of research were identified, some of which represented preparatory work rather than research per se. The three most highly ranked priorities were the documentation of data fields in each country's hospital administrative data (average score 8.4), the translation of patient safety indicators from ICD-9 to ICD-10 (average score 8.0), and the development and validation of algorithms to verify the logic and internal consistency of coding in hospital abstract data (average score 7.0). CONCLUSION: The group discussions resulted in a list of expert views on critical international priorities for future methodological research relating to health administrative data. The consortium's members welcome contacts from investigators involved in research using health administrative data, especially in cross-jurisdictional collaborative studies or in studies that illustrate the application of ICD-10.

Algorithms↗
PubMed2006

Aspirin use and outcomes in a community-based cohort of 7352 patients discharged after first hospitalization for heart failure.

BACKGROUND: The safety of aspirin in heart failure (HF) has been called into question, particularly in those patients (1) without coronary disease, (2) with renal dysfunction, or (3) treated with low-dose angiotensin-converting enzyme (ACE) inhibitors and high-dose aspirin. METHODS AND RESULTS: We examined prescription patterns and outcomes (all-cause mortality and/or HF readmission) in patients discharged from 103 Canadian hospitals between April 1999 and March 2001 after a first hospitalization for HF. Of 7352 patients with HF (mean age, 75 years; 44% without coronary disease and 29% with renal dysfunction), 2785 (38%) died or required HF readmission within the first year. Compared with nonusers, aspirin users were no more likely to die or require HF readmission (hazard ratio [HR], 1.02 [0.91 to 1.16]), even in patients without coronary disease (HR, 0.98 [0.78 to 1.22]) or patients with renal dysfunction (HR, 1.13 [0.94 to 1.36]). On the other hand, users of ACE inhibitors were less likely to die or require HF readmission (HR, 0.87 [0.79 to 0.96]), even if they were using aspirin (HR, 0.86 [0.77 to 0.95]). There were no dose-dependent interactions between aspirin and ACE inhibitors. CONCLUSIONS: In this observational study, aspirin use was not associated with an increase in mortality rates or HF readmission rates, and aspirin did not attenuate the benefits of ACE inhibitors, even in patients without coronary disease, patients with renal dysfunction, or patients treated with high-dose aspirin and low-dose ACE inhibitors.

Aged↗
PubMed2006

Quality of life after coronary revascularization in the elderly.

AIMS: To describe health status outcomes at 4 years for a cohort of elderly patients with cardiac disease. METHODS AND RESULTS: Using the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease, an outcomes initiative capturing all patients undergoing cardiac catheterization in Alberta, Canada, health status was measured using the Seattle Angina Questionnaire (SAQ) and crude and risk-adjusted outcomes were determined and compared for patients treated with percutaneous coronary intervention or coronary artery bypass surgery (CABG) vs. medical therapy. Response rates among surviving, consenting patients were 64.8% for patients <70 years (n=7883), 77.3% for patients aged 70-79 years (n=2940), and 77.7% for patients >or=80 years of age (n=439). For patients aged <70 years, and those aged 70-79 years, for all dimensions of the SAQ, scores were significantly better for patients treated with revascularization procedures than with medical therapy. For patients over the age of 80 years, scores for patients treated with CABG in particular were significantly better, with the exception of exertional capacity. At 3 years, all scores remained stable or improved, and continued to favour revascularization. CONCLUSION: Elderly patients undergoing revascularization have better health status at 4 years than do those in the same age group who do not undergo revascularization. These findings suggest that age should not deter against revascularization given the combined survival and quality-of-life benefits.

Aged↗
PubMed2006

A randomized trial to assess the impact of opinion leader endorsed evidence summaries on the use of secondary prevention strategies in patients with coronary artery disease: the ESP-CAD trial protocol [NCT00175240].

BACKGROUND: Although numerous therapies have been shown to be beneficial in the prevention of myocardial infarction and/or death in patients with coronary disease, these therapies are under-used and this gap contributes to sub-optimal patient outcomes. To increase the uptake of proven efficacious therapies in patients with coronary disease, we designed a multifaceted quality improvement intervention employing patient-specific reminders delivered at the point-of-care, with one-page treatment guidelines endorsed by local opinion leaders ("Local Opinion Leader Statement"). This trial is designed to evaluate the impact of these Local Opinion Leader Statements on the practices of primary care physicians caring for patients with coronary disease. In order to isolate the effects of the messenger (the local opinion leader) from the message, we will also test an identical quality improvement intervention that is not signed by a local opinion leader ("Unsigned Evidence Statement") in this trial. METHODS: Randomized trial testing three different interventions in patients with coronary disease: (1) usual care versus (2) Local Opinion Leader Statement versus (3) Unsigned Evidence Statement. Patients diagnosed with coronary artery disease after cardiac catheterization (but without acute coronary syndromes) will be randomly allocated to one of the three interventions by cluster randomization (at the level of their primary care physician), if they are not on optimal statin therapy at baseline. The primary outcome is the proportion of patients demonstrating improvement in their statin management in the first six months post-catheterization. Secondary outcomes include examinations of the use of ACE inhibitors, anti-platelet agents, beta-blockers, non-statin lipid lowering drugs, and provision of smoking cessation advice in the first six months post-catheterization in the three treatment arms. Although randomization will be clustered at the level of the primary care physician, the design effect is anticipated to be negligible and the unit of analysis will be the patient. DISCUSSION: If either the Local Opinion Leader Statement or the Unsigned Evidence Statement improves secondary prevention in patients with coronary disease, they can be easily modified and applied in other communities and for other target conditions.

Journal Article↗
PubMed2006

Refined characterization of the association between kidney function and mortality in patients undergoing cardiac catheterization.

AIMS: Chronic kidney disease is associated with an increased risk of cardiovascular morbidity and mortality. The level of kidney function at which this risk increases remains to be determined. We sought to characterize the relationship between kidney function and survival among patients with cardiovascular disease (CVD) undergoing cardiac catheterization using estimated glomerular filtration rate (eGFR) and graded refinements in the classification of kidney function. METHODS AND RESULTS: We included 8521 of 11 778 (72.3%) consecutive patients undergoing cardiac catheterization between 1 January 1999 and 31 December 2001 from the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease database. eGFR as a categorical and continuous variable was used to define kidney function. The outcome was all-cause mortality. During a median (interquartile range) follow-up of 2.2 (1.5-3.1) years, and after adjustment for clinical risk factors and severity of coronary disease, there was a steady incremental decrease in survival post-catheterization corresponding to a decline in eGFR categories of 10 mL/min/1.73 m(2). When eGFR was modelled as a continuous variable, there was an increased risk of death noted at an eGFR below 79 mL/min/1.73 m(2). Below an eGFR of 70 mL/min/1.73 m,(2), there was an approximate 17.2% relative increase in risk for every 10 unit decrease in eGFR (95% CI 8.4-26.6%). CONCLUSION: The risk of death post-cardiac catheterization is elevated when eGFR is < or =79 mL/min/1.73 m(2). These findings provide considerable refinement in our understanding of eGFR as a powerful prognostic marker in patients with CVD undergoing cardiac catheterization.

Cardiac Catheterization↗
PubMed2006

Ordinal regression model and the linear regression model were superior to the logistic regression models.

OBJECTIVE: Ordinal scales often generate scores with skewed data distributions. The optimal method of analyzing such data is not entirely clear. The objective was to compare four statistical multivariable strategies for analyzing skewed health-related quality of life (HRQOL) outcome data. HRQOL data were collected at 1 year following catheterization using the Seattle Angina Questionnaire (SAQ), a disease-specific quality of life and symptom rating scale. STUDY DESIGN AND SETTING: In this methodological study, four regression models were constructed. The first model used linear regression. The second and third models used logistic regression with two different cutpoints and the fourth model used ordinal regression. To compare the results of these four models, odds ratios, 95% confidence intervals, and 95% confidence interval widths (i.e., ratios of upper to lower confidence interval endpoints) were assessed. RESULTS: Relative to the two logistic regression analysis, the linear regression model and the ordinal regression model produced more stable parameter estimates with smaller confidence interval widths. CONCLUSION: A combination of analysis results from both of these models (adjusted SAQ scores and odds ratios) provides the most comprehensive interpretation of the data.

Adolescent↗
PubMed2006

Variation in health services utilization among ethnic populations.

BACKGROUND: Although racial and ethnic disparities in health services utilization and outcomes have been extensively studied in several countries, this issue has received little attention in Canada. We therefore analyzed data from the 2001 Canadian Community Health Survey to compare the use of health services by members of visible minority groups and nonmembers (white people) in Canada. METHODS: Logistic regression was used to compare physician contacts and hospital admissions during the 12 months before the survey and recent cancer screening tests. Explanatory variables recorded from the survey included visible minority status, sociodemographic factors and health measures. RESULTS: Respondents included 7057 members of visible minorities and 114,255 white people for analysis. After adjustments for sociodemographic and health characteristics, we found that minority members were more likely than white people to have had contact with a general practitioner (adjusted odds ratio [OR] 1.28, 95% confidence interval [CI] 1.14-1.42), but not specialist physicians (OR 1.01, 95% CI 0.93-1.10). Members of visible minorities were less likely to have been admitted to hospital (OR 0.83, 95% CI 0.70- 0.98), tested for prostate-specific antigen (OR 0.64, 95% CI 0.52-0.79), administered a mammogram (OR 0.68, 95% CI 0.59-0.80) or given a Pap test (OR 0.47, 95% CI 0.39-0.56). INTERPRETATION: Use of health services in Canada varies considerably by ethnicity according to type of service. Although there is no evidence that members of visible minorities use general physician and specialist services less often than white people, their utilization of hospital and cancer screening services is significantly less.

Adolescent↗
PubMed2006

Location of residence associated with the likelihood of patient visit to the preoperative assessment clinic.

BACKGROUND: Outpatient preoperative assessment clinics were developed to provide an efficient assessment of surgical patients prior to surgery, and have demonstrated benefits to patients and the health care system. However, the centralization of preoperative assessment clinics may introduce geographical barriers to utilization that are dependent on where a patient lives with respect to the location of the preoperative assessment clinic. METHODS: The association between geographical distance from a patient's place of residence to the preoperative assessment clinic, and the likelihood of a patient visit to the clinic prior to surgery, was assessed for all patients undergoing surgery at a tertiary health care centre in a major Canadian city. The odds of attending the preoperative clinic were adjusted for patient characteristics and clinical factors. RESULTS: Patients were less likely to visit the preoperative assessment clinic prior to surgery as distance from the patient's place of residence to the clinic increased (adjusted OR = 0.52, 95% CI 0.44-0.63 for distances between 50-100 km, and OR = 0.26, 95% CI 0.21-0.31 for distances greater than 250 km). This 'distance decay' effect was remarkable for all surgical specialties. CONCLUSION: The present study demonstrates that the likelihood of a patient visiting the preoperative assessment clinic appears to depend on the geographical location of patients' residences. Patients who live closest to the clinic tend to be seen more often than patients who live in rural and remote areas. This observation may have implications for achieving the goals of equitable access, and optimal patient care and resource utilization in a single universal insurer health care system.

Adult↗
PubMed2006

Acetylcysteine in the prevention of contrast-induced nephropathy: a case study of the pitfalls in the evolution of evidence.

During the past 5 years, 19 randomized controlled trials, 4 prospective nonrandomized studies, and 11 meta-analyses that explored the role of acetylcysteine for prevention of contrast-induced nephropathy have been published. Herein, we summarize this literature and demonstrate that these 34 empirical studies have not yet conclusively resolved this research question. We use the evidence on acetylcysteine as a case study of how research evidence accumulates and consider whether an alternative approach to investigating the question of acetylcysteine's efficacy could have resulted in a more definitive conclusion. We consider the broader lessons learned from this acetylcysteine case study for the medical and research communities and propose specific steps that could be taken to improve the future coordination of research activity to ultimately yield more meaningful and definitive evidence on important clinical questions.

Acetylcysteine↗
PubMed2006

External validation of a percutaneous coronary intervention mortality prediction model in patients with acute coronary syndromes.

BACKGROUND: The recently published Michigan outcome prediction model (MM) for inhospital mortality was developed and validated on a series of consecutive patients undergoing percutaneous coronary intervention (PCI). Our purpose was to externally validate the performance of the MM in 2 separate cohorts of patients with acute coronary syndrome (ACS) undergoing PCI in Canada. METHODS: A validation of the MM and development of an extended MM were performed on data describing 10,050 patients from the APPROACH prospective cohort study between January 1995 and December 2000. Performance of both models was assessed on an external data set of 3259 PCI cases from the British Columbia Cardiac Registries. Only patients with a diagnosis of ACS were included in the study. RESULTS: The original MM predicted death rates ranging from 0.1% to 60.6%, but lacked accuracy to predict inhospital mortality as severity increased. The extended MM predicted death rates more widely from 0.0% to a high of 91.0% with better accuracy to predict inhospital death in patients with ACS undergoing PCI. The areas under the receiver operating characteristic curve for the MM and the extended MM on the external validation data set were 0.93 and 0.95, respectively. CONCLUSION: The MM predicts death after PCI in patients with ACS and identifies a clear gradient of risk. However, the enhanced MM developed specifically for the subset of patients with ACS demonstrated better prediction and cross-validated performance. These prediction rules can be useful for risk-adjustment analyses and for prognostication for individual patients.

Aged↗
PubMed2006

Public versus private institutional performance reporting: what is mandatory for quality improvement?

BACKGROUND: In the past 11 years, Ontario has generated institution-level performance report cards on outcomes of coronary artery bypass graft (CABG) surgery. The objective of this study was to evaluate the differences in patient characteristics and outcomes observed during the transition from no reporting to confidential, and ultimately public performance report cards for CABG surgery in a public health system. METHODS: We used clinical and administrative data to assess crude, expected, and risk-adjusted 30-day mortality rates after isolated CABG surgery in Ontario for 67693 patients from September 1, 1991, to March 31, 2002. Confidence intervals on relative mortality reductions were determined by bootstrapping. We compared 30-day mortality trends to a control outcome (risk-adjusted 30-day all-cause readmission). We analyzed inhospital mortality trends for Ontario compared with the rest of Canada for the period from 1992 to 1998. RESULTS: The risk-adjusted 30-day mortality rate decreased 29% (95% CI 21-39) from the era of no reporting (1991-1993) to confidential reporting (1994-1998). There was no further decrease with public reporting (1999-2001). The control outcome of 30-day readmission did not decrease across reporting eras. Inhospital mortality fell significantly faster in Ontario during the period of confidential reporting than in other parts of Canada. CONCLUSION: Ontario CABG mortality outcomes improved sharply after provider results were confidentially disclosed at an institutional level. No such changes were seen for nondisclosed outcomes or regions outside Ontario. Further public reporting of outcomes had no discernible impact on performance. These results are consistent with the hypothesis that confidential disclosure of outcomes was sufficient to accelerate quality improvement in a public system with little competition for patients between hospitals.

Aged↗
PubMed2006

Prophylactic amiodarone for prevention of atrial fibrillation after cardiac surgery: a meta-analysis.

Amiodarone has been proposed to decrease atrial fibrillation after cardiac surgery. The literature was systematically reviewed for randomized trials comparing amiodarone with control for prevention of atrial fibrillation. Data were extracted on study characteristics, quality, and incidence of atrial fibrillation, cardiovascular outcomes, and length of hospitalization. Nineteen trials were included. Amiodarone reduced the odds ratio of atrial fibrillation (0.50; 95% confidence interval [CI]: 0.43 to 0.59, p < 0.0001), ventricular tachyarrhythmias (0.39; 95% CI: 0.26 to 0.58, p < 0.0001), and strokes (0.53; 95% CI: 0.30 to 0.92, p = 0.02). Amiodarone reduced hospital stay (0.6 days; 95% CI: 0.4 to 0.8, p < 0.0001). Amiodarone decreased atrial fibrillation, reduced perioperative ventricular tachyarrhythmias and strokes, and reduced duration of hospitalization. The current evidence supports recommending the routine use of perioperative amiodarone for cardiac surgery.

Adrenergic beta-Antagonists↗
PubMed2006

Kaplan-Meier methods yielded misleading results in competing risk scenarios.

BACKGROUND AND OBJECTIVE: Time-to-event curves are routinely presented in the medical literature. The most widely used method is the Kaplan-Meier (K-M) method, but this analysis approach may not be appropriate when an analysis focuses on time-to-first event in scenarios where there are competing events. We compared K-M methods applying various censoring approaches with the lesser-known "cumulative incidence competing risks" (CICR) method in an analysis of competing events. METHODS: A registry containing data on 21,624 patients undergoing cardiac catheterization was analyzed. Time to coronary artery bypass grafting (CABG) was assessed in an analysis for which percutaneous coronary intervention and death were competing events. Time-to-CABG curves were calculated using the "K-M censor all method," "K-M censor death only method," "K-M ignore all method," and the CICR method. RESULTS: One-year CABG rates calculated for the K-M "censor all," "censor death only," and "ignore all" methods were 28.8%, 22.8%, and 22.4%, respectively compared to the "actual" rate of 20.8%. For the CICR method, the corresponding 1-year rate was identical to the "actual" rate. CONCLUSION: In situations with competing risks, and where an analysis focuses on first events, the CICR method is most appropriate, as K-M methods will tend to overestimate event rates.

Angioplasty, Balloon, Coronary↗
PubMed2006

Myocardial infarction on snow days: incidence, procedure, use and outcomes.

BACKGROUND: Snowfall can cause chaos in urban centres and put considerable stress on health care systems. Given that myocardial infarction (MI) is a condition that may be triggered or aggravated by stress, and that health system stress could influence the typical care provided to patients with MI, a study was conducted comparing 'snow days' with 'nonsnow days', specifically assessing the incidence of MI, the use of acute procedures and in-hospital mortality. METHODS: Hospital discharge data were used on all patients discharged after MI. These data were merged with data from Environment Canada to determine the amount of snowfall that occurred on any given day. The use of acute procedures was determined by linking to data from the Alberta Provincial PRoject for Outcomes Assessment in Coronary Heart disease (APPROACH). Snow days were defined as days when at least 5 cm of snow fell, and the two subsequent days were included because of the lingering effect of 'urban chaos' that can ensue after significant snowfall. The average incidence of MIs on snow days versus nonsnow days was then determined. Risk-adjusted odds ratios for the use of direct percutaneous coronary intervention and in-hospital mortality were also determined. RESULTS: There were 61 snow days and 575 nonsnow days. The incidence of MI (incidence density ratio of 1.08, 95% CI 0.82 to 3.10) and the use of direct percutaneous coronary intervention (adjusted OR=1.07, 95% CI 0.74 to 1.54) were slightly higher on snow days. In-hospital mortality trended toward being lower (adjusted OR=0.54, 95% CI 0.28 to 1.04) for patients admitted on snow days, although none of these differences were statistically significant. CONCLUSION: Despite the potential for the significant adverse effects of snow days on the incidence of MI, the use of acute procedures and outcomes, these findings suggest only minor effects, if any.

Aged↗