Comparison of Canadian versus American emergency department visits for acute asthma

BACKGROUND:

Acute asthma is a common emergency department (ED) presentation in both Canada and the United States.

OBJECTIVE:

To compare ED asthma management and outcomes between Canada and the United States.

MEHODS:

A prospective cohort study of 69 American and eight Canadian EDs was conducted. Patients aged two to 54 years who presented with acute asthma underwent a structured ED interview and telephone follow-up two weeks later.

RESULTS:

A total of 3031 patients were enrolled. Canadian patients were more likely to be white (89% versus 22%; P<0.001), have health insurance (100% versus 69%; P<0.001) and identify a primary care provider (89% versus 64%; P<0.001) than American patients. In addition, Canadian patients were more likely to be using inhaled corticosteroids (63% versus 44%; P<0.001) and had higher initial peak expiratory flow (61% versus 48%; P<0.001). In the ED, Canadians received fewer beta-agonist (one versus two; P<0.001) and more anticholinergic (two versus one; P<0.001) treatments in the first hour; use of systemic corticosteroids was similar (60% versus 68%; P=0.13). Canadians were less likely to be hospitalized (11% versus 21%; P=0.02). Corticosteroids were prescribed similarly at discharge (60% versus 69%; P=0.13); however, Canadians were discharged more commonly on inhaled corticosteroids (63% versus 11%; P<0.001) and relapses were similar.

CONCLUSIONS:

Canadian patients with acute asthma have fewer barriers to primary care and are more likely to be on preventive medications, both before the ED visit and following discharge. Admissions rates are higher in the United States; however, relapse after discharge is similar between countries. These findings highlight the influences of preventive practices and heath care systems on ED visits for asthma.     

Measurement of von Willebrand factor as the marker of endothelial dysfunction in vascular diseases

BACKGROUND:

von Willebrand factor is a blood glycoprotein that is required for normal hemostasis. Its level can be increased by endothelial cell damage.

HYPOTHESIS:

von Willebrand factor is a suitable marker of endothelial dysfunction.

METHODS:

von Willebrand factor activity was determined by ELISA in patients with acute coronary syndromes, acute stroke and chronic vascular diseases, and was compared with the values of healthy controls.

RESULTS:

von Willebrand factor activity of patients in each group was significantly higher (P<0.001) than that of the control group. The values of patients with acute coronary syndrome and acute stroke were significantly higher (P<0.05 and P<0.01, respectively) than those of patients with chronic vascular diseases. von Willebrand factor activity was significantly higher in patients with acute coronary syndrome and acute stroke (P<0.05 and P<0.01, respectively) on the sixth day than on admission.

CONCLUSIONS:

By measuring von Willebrand factor activity, a considerable, significant difference could be found between healthy people and chronic and acute vascular patients. The routine measurement of von Willebrand factor activity in vascular patients as an index of endothelial dysfunction may have clinical importance, because detection of this marker can be a noninvasive way of assisting diagnosis and indicating disease progression.     

Cardiovascular risk factor awareness in a disadvantaged inner-city population--implications for preventive strategies

BACKGROUND:

Disadvantaged inner-city populations have significantly higher cardiovascular disease (CVD) mortality rates than the general population. Whether a deficiency in the level of awareness, a prerequisite for change, exists that contributes to this socioeconomic divide has not been well established.

OBJECTIVES:

To address CVD risk by assessing the knowledge of CVD risk factors of an inner-city population and comparing it with that of the general population by establishing determinants of CVD knowledge and identifying potential barriers to CVD risk factor reduction in the inner city.

METHODS:

Cross-sectional survey of 136 consecutive patients 40 years of age and older attending an inner-city community health centre. The comparison group consisted of 807 age-matched respondents from the Canadian Heart Health Study, a random sample survey of the general adult Canadian population. Outcome measures included CVD risk factor knowledge, CVD risk factor prevalence and barriers to reducing CVD risk.

RESULTS:

There was no significant difference between inner-city respondent ability to name five of the seven CVD risk factors compared with the general population. Two CVD risk factors were more readily recalled by the inner-city group (lack of exercise, P<0.001; heredity, P=0.003). The average number of risk factors named by an individual from the inner city was significantly higher than the general population (3.1 versus 2.6; P<0.001). Among the inner-city respondents, socioeconomic factors, including higher education level (OR 5.224; P<0.001) and being married (OR 3.651; P=0.008), were independently related to good CVD knowledge; high CVD risk was not related. Lack of motivation (57%), lack of time (34%) and lack of money (30%) were commonly reported as barriers to addressing CVD risk.

CONCLUSIONS:

Elevated CVD risk in the inner city may not be attributable to a deficiency in the level of awareness. However, the relationship between socioeconomic status and knowledge is maintained within the lowest social class tier. The identification of barriers linked to inner-city life has implications for prevention of CVD in the inner city; results suggest that interventions that combine health education with motivational approaches, while necessary, may not be sufficient.     

Biventricular pacing: impact on exercise-induced increases in mitral insufficiency in patients with chronic heart failure

INTRODUCTION:

Mitral regurgitation (MR) in chronic heart failure (CHF) patients frequently worsens with exercise. Cardiac resynchronization therapy (CRT) reduces MR at rest, but its effects on exercise-induced worsening of MR are incompletely explored. The present study examined the influence of CRT on MR during submaximal exercise in CHF patients.

METHODS:

Eleven patients with CHF who were treated with CRT underwent echocardiography while performing steady-state exercise during four conduction modes (intrinsic rhythm, right ventricular [RV], biventricular [BiV] and left ventricular [LV] pacing). Measurements of MR were jet area planimetry, effective regurgitant orifice area, peak MR flow rate and regurgitant volume.

RESULTS:

At rest and during exercise, there were no differences in dyssynchrony between intrinsic rhythm and RV pacing. BiV and LV pacing reduced dyssynchrony at rest and during exercise compared with intrinsic conduction and RV pacing, and there were no differences in the magnitude of these effects between these two pacing modes. At rest, RV pacing increased MR compared with intrinsic conduction (MR regurgitant volume; P<0.05), whereas BiV and LV pacing reduced MR (reductions in effective regurgitant orifice area and jet area; P<0.02, and MR flow rate; P<0.05 with BiV pacing from intrinsic conduction). MR significantly increased on exercise with intrinsic rhythm and RV pacing, whereas with LV and BiV pacing, there were no significant exercise-induced increases in any MR variable. There were relationships between changes in measures of dyssynchrony and reductions in MR at rest and during exercise.

CONCLUSIONS:

CRT reduces MR at rest and during exercise, and prevents exercise-induced MR. Reductions in MR during exercise correlate with improvements in dyssynchrony.     

Impact of the metabolic syndrome on aortic pulse pressure and ascending aortic pulsatility in patients with angiographically normal coronary arteries

BACKGROUND:

Large artery stiffness is a major determinant of pulse pressure (PP), and PP at baseline has been associated with future coronary events.

OBJECTIVE:

To evaluate the impact of the metabolic syndrome on aortic PP and ascending aortic pulsatility (AP) in patients with angiographically normal coronary arteries.

METHODS:

Forty-two patients with the metabolic syndrome and 40 age-matched control subjects without the metabolic syndrome were included in the study. All subjects had normal coronary arteries. Diagnosis of the metabolic syndrome was based on the International Diabetes Federation guidelines published in 2005. Ascending AP was estimated as the ratio of aortic PP to mean blood pressure.

RESULTS:

Aortic PP (59±12 mmHg versus 43±10 mmHg; P<0.001) and ascending AP (0.54±0.10 versus 0.48±0.10; P<0.001) were significantly higher in the metabolic syndrome group. Multiple regression analysis revealed statistically independent relationships between ascending AP and fasting blood glucose, waist circumference and systolic blood pressure (model R²=0.408; P<0.001). The metabolic syndrome, as a whole, was also independently associated with both ascending AP (P<0.01) and aortic PP (P<0.01).

CONCLUSION:

The data showed that the metabolic syndrome is independently associated with increased aortic PP and ascending AP in patients with normal coronary arteries, suggesting aortic stiffness as one of the possible mechanisms underlying the excess cardiovascular risk associated with the metabolic syndrome.     

Disparities in the Use of Internet and Telephone Medication Refills among Linguistically Diverse Patients

Background

Health systems are increasingly implementing remote telephone and Internet refill systems to enhance patient access to medication refills. Remote refill systems may provide an effective approach for improving medication non-adherence, but more research is needed among patients with limited English proficiency with poor access to remote refill systems.

Objective

To compare the use of remote medication refill systems among limited-English-proficiency (LEP) and English-proficient (EP) patients with chronic conditions.

Methods

Cross-sectional survey in six languages/dialects (English, Cantonese, Mandarin, Korean, Vietnamese, and Spanish) of 509 adults with diabetes, hypertension, or hyperlipidemia. Primary study outcomes were self-reported use of 1) Internet refills, 2) telephone refills, and 3) any remote refill system. LEP was measured by patient self-identification of a primary language other than English and a claims record of use of an interpreter. Other measures were age, gender, education, years in the U.S., insurance, health status, chronic conditions, and number of prescribed medications. Analyses included multivariable logistic regression weighted for survey non-response.

Results

Overall, 33.1 % of patients refilled their medications by telephone and 31.6 % by Internet. Among LEP patients (n = 328), 31.5 % refilled by telephone and 21.2 % by Internet, compared with 36.7 % by telephone and 52.7 % by Internet among EP patients (n = 181). Internet refill by language groups were as follows: English (52.7 %), Cantonese (34.9 %), Mandarin (17.4 %), Korean (16.7 %), Vietnamese (24.4 %), and Spanish (12.6 %). Compared to EP patients, LEP patients had lower use of any remote refill system (adjusted odds ratio [AOR] 0.18; p < 0.001),

Conclusions

LEP patients are significantly less likely than EP patients to use any remote medication refill system. Increased reliance on current systems for remote medication refills may increase disparities in health outcomes affecting LEP patients with poor access to telephone and Internet medication refills.Key Words: language barriers, minority health, survey research, disparities, adherence     

Wait times for sleep apnea care in Ontario: A multidisciplinary assessment

BACKGROUND:

Obstructive sleep apnea (OSA) is a highly prevalent disorder that is associated with significant patient morbidity and societal burden. In general, wait times for health care in Ontario are believed to be lengthy; however, many diseases lack specific corroborative wait time data.

OBJECTIVE:

To characterize wait times for OSA care in Ontario.

METHODS:

Cross-sectional survey. A survey tool was designed and validated to question physicians involved in OSA care about the length of the wait times their patients experience while traversing a simplified model of OSA care. The survey was sent to all otolaryngologists and respirologists in the province, as well as to a random sample of provincial family physicians.

RESULTS:

Patients waited a mean of 11.6 months to initiate medical therapy (continuous positive airway pressure), and 16.2 months to initiate surgical therapy. Sleep laboratory availability appeared to be the major restriction in the patient management continuum, with each additional sleep laboratory in a community associated with a 20% decrease in overall wait times. Smaller community sizes were paradoxically associated with shorter wait times for sleep studies (P<0.01) but longer wait times for OSA surgery (P<0.05). Regression analysis yielded an r² of 0.046; less than 5% of the wait time variance could be explained by the simplified model.

CONCLUSION:

Patients experienced considerable wait times when undergoing management for OSA. This has implications for both individual patient care and public health in general.     

Cardiac and neuromuscular implications of left bundle branch block in left ventricular hypertrabeculation/noncompaction

BACKGROUND:

Left bundle branch block (LBB) is frequently found in left ventricular hypertrabeculation/noncompaction (LVHT).

OBJECTIVES:

To compare LVHT patients with and without LBB regarding LVHT location and extension, left ventricular function, symptoms, electrocardiographic findings, prevalence of neuromuscular disorders (NMDs) and mortality during follow-up.

METHODS:

The charts of patients who underwent transthoracic echocardiographic examination at the Krankenanstalt Rudolfstiftung (Wien, Austria) between June 1995 and November 2006 were examined.

RESULTS:

LVHT was diagnosed in 102 patients (30 women) with a mean (± SD) age of 53±16 years (range 14 to 94 years). A specific NMD was diagnosed in 21 patients and an NMD of unknown etiology was diagnosed in 47. The neurological investigation was normal in 14 patients and 20 patients refused the investigation. The 24 patients with LBB were older (61 versus 51 years of age; P<0.01), and suffered from exertional dyspnea (96% versus 59%; P<0.01) and heart failure (79% versus 46%; P<0.01) more often than patients without LBB. LBB patients had less frequent tall QRS complexes (8% versus 47%; P<0.01) and ST-T wave abnormalities (4% versus 50%; P<0.01) than patients without LBB. Patients with LBB had a larger left ventricular end-diastolic diameter (73 mm versus 61 mm; P<0.01), worse left ventricular fractional shortening (15% versus 26%; P<0.01) and more extensive LVHT (1.8 versus 1.5 ventricular segments; P<0.05). The prevalence of NMDs did not differ between patients with and without LBB. Survival did not differ between patients with and without LBB during follow-up.

CONCLUSIONS:

LBB is associated with increased age, decreased systolic function and increased extension of LVHT. Whether LBB is a prognostic factor in LVHT remains speculative.     

Comparison of Canadian versus United States emergency department visits for chronic obstructive pulmonary disease exacerbation

INTRODUCTION:

Despite the frequency of emergency department (ED) visits for chronic obstructive pulmonary disease (COPD) exacerbation, little is known about practice variation in EDs.

OBJECTIVES:

To examine the differences between Canadian and United States (US) COPD patients, and the ED management they receive.

METHODS:

A prospective multicentre cohort study was conducted involving 29 EDs in the US and Canada. Using a standard protocol, consecutive ED patients with COPD exacerbations were interviewed, their charts reviewed and a two-week telephone follow-up completed. Comparisons between Canadian and US patients, as well as their treatment and outcomes, were made. Predictors of antibiotic use were determined by multivariate logistic regression.

RESULTS:

Of 584 patients who had physician-diagnosed COPD, 397 (68%) were enrolled. Of these, 63 patients (16%) were from Canada. Canadians were older (73 years versus 69 years; P=0.002), more often white (97% versus 65%; P<0.001), less educated (P=0.003) and more commonly insured (P<0.001) than the US patients. US patients more commonly used the ED for their usual COPD medications (17% versus 3%; P=0.005). Although Canadian patients had fewer pack-years of smoking (45 pack-years versus 53 pack-years; P=0.001), current COPD medications and comorbidities were similar. At ED presentation, Canadian patients were more often hypoxic and symptomatic. ED treatment with inhaled beta-agonists (approximately 90%) and systemic corticosteroids (approximately 65%) were similar; Canadians received more antibiotics (46% versus 25%; P<0.001) and other treatments (29% versus 11%; P=0.002). Admission rates were similar in both countries (approximately 65%), although Canadian patients remained in the ED longer than the US patients (10 h versus 5 h, respectively; P<0.001).

CONCLUSIONS:

Overall, patients with acute COPD in Canada and the US appear to have similar history, ED treatment and outcomes; however, Canadian patients are older and receive more aggressive treatment in the ED. In both countries, the prolonged length of stay and high admission rate contribute to the ED overcrowding crisis facing EDs.     

QT interval dispersion pattern in patients with acute ischemic stroke: Does the site of infarction matter?

BACKGROUND:

QT interval dispersion (QTD) is an independent predictor of outcome following acute neurological events.

OBJECTIVES:

To explore QTD patterns and their relation to the affected cerebral region in patients with acute ischemic stroke.

METHODS:

Thirty patients with first acute ischemic stroke (the first stroke the patients had ever experienced) (study group) and 30 healthy controls (control group) were enrolled. Patients underwent magnetic resonance imaging to confirm and localize cerebral damage. Patients in the study group were further subdivided according to the site of infarction into four subgroups – namely, cortical, subcortical, brain stem and cerebellar infarctions, as well as according to insular involvement. All included subjects underwent 12-lead electrocardiography to measure QTD and corrected QT dispersion (QTcD).

RESULTS:

In the study group, both QTD and QTcD on the first hospitalization day were significantly higher than in the control group (P<0.05 for both). Similarly, in the study group, both QTD and QTcD values on the first hospitalization day were significantly higher than the respective values on the third day (P<0.001 for both). No significant differences were found among the four territorial subgroups, or between right- and left-sided subgroups, regarding QT interval measurements, whether on the first or third day (P>0.05 for all). However, ‘first-day’ QTD and QTcD of patients with insular involvement were significantly higher than in those without such involvement (P<0.001 for both).

CONCLUSIONS:

Both QTD and QTcD increased significantly in patients with acute ischemic stroke during the first hospitalization day. This increase of ‘first-day’ QTD and QTcD was significantly higher in patients with insular involvement than in those without such involvement.     

Health care resource use and costs in Crohn's disease before and after infliximab therapy

BACKGROUND:

Infliximab therapy in patients with Crohn’s disease decreases resource use; however, the overall impact on health-related expenditures is unclear, especially beyond one year of study.

METHODS:

A retrospective analysis of economic data one and two years before and after infliximab therapy was performed using patients who served as their own controls. Total health care resource use and direct health care costs were compared for patients with or without fistulae.

RESULTS:

Patients with one (n=66) and two (n=39) years of economic data before and after infliximab treatment had their resource use and direct health care costs estimated. In the year following initiation of infliximab therapy, there were significant decreases in health care use, reflected in total hospital days (495 to 155 [P<0.05]), inpatient colonoscopies (46 to 24 [P<0.05]), outpatient colonoscopies (58 to 33 [P<0.05]) and major surgeries (10 to 2 [P<0.05]). Direct health care costs of inpatient costs for luminal (−$1,747 [P<0.05]) and fistulizing disease (−$2,530 [P<0.05]), major surgeries (−$1240 [P<0.05]) and outpatient colonoscopies (−$184 [P<0.05]) were also significantly reduced before and after infliximab therapy. Total direct health care costs, including the drug cost of infliximab, increased ($21,416 [P<0.05]). In general, the trends in health care costs analyzed over four consecutive years paralleled the two consecutive-year analysis.

CONCLUSIONS:

Infliximab therapy in patients with Crohn’s disease resulted in a significant decrease in both resource use and health care costs, but an increase in total direct health care costs once the cost of infliximab was added.     

Effects of the indoor environment on the fraction of exhaled nitric oxide in school-aged children

BACKGROUND:

The fractional concentration of exhaled nitric oxide (FeNO) appears to be a good marker for airway inflammation in children with asthma.

OBJECTIVE:

To evaluate the effect of environmental exposures on exhaled nitric oxide in a community sample of children.

METHODS:

The relationship among exhaled nitric oxide, underlying disease and home environmental exposures was examined using questionnaire data and measurement of exhaled nitric oxide in a cross-sectional study of 1135 children that included healthy children, and children with allergies and/or asthma who were attending grades 4 through 6 in Windsor, Ontario.

RESULTS:

Among healthy children, there was a positive association between FeNO and occupancy (P<0.02). Compared with forced air and hot water radiant heat, electric baseboard heating was associated with a significant increase of FeNO in healthy children (P=0.007) and children with allergies (P=0.043). FeNO was not associated with environmental tobacco smoke exposure or reported surface mold. The presence of pet dog(s), but not cats, was associated with a significantly lower FeNO in healthy children (P<0.001) and in children with reported allergies (P<0.001).

CONCLUSIONS:

The type of heating system, but not previously reported environmental tobacco smoke or mold exposure appears to affect exhaled nitric oxide in children. Exposure to different types of pets may have disparate effects on airway inflammation.     

Association between proximity to major roads and sputum cell counts

BACKGROUND:

Air pollution caused by motor vehicle emissions has been associated with exacerbations of obstructive airway diseases; however, the nature of the resulting bronchitis has not been quantified.

OBJECTIVE:

To examine whether proximity to major roads or highways is associated with an increase in sputum neutrophils or eosinophils, and to evaluate the effect of proximity to roads on spirometry and exacerbations in patients with asthma.

METHODS:

A retrospective study of 485 sputum cell counts from patients attending a tertiary chest clinic in Hamilton, Ontario, identified eosinophilic or neutrophilic bronchitis. Patients’ residences were geocoded to the street network of Hamilton using geographic information system software. Associations among bronchitis, lung function, and proximity to major roads and highways were examined using multinomial logistic and multivariate linear regression analyses adjusted for patient age, smoking status and corticosteroid medications.

RESULTS:

Patients living within 1000 m of highways showed an increased risk of bronchitis (OR 3.8 [95% CI 1.0 to 13.7]; P<0.05), particularly neutrophilic bronchitis (OR 4.7 [95% CI 1.2 to 18.7]; P<0.05) as well as an increased risk of an asthma diagnosis (OR 1.9 [95% CI 1.0 to 3.4]; P<0.05). Patients living within 300 m of a major road were at increased risk for an asthma exacerbation (OR 1.9 [95% CI 1.5 to 15.5]; P<0.01) and lower lung function, particularly in women (P=0.036).

CONCLUSION:

In patients with airway diseases, living close to a highway or major road was associated with neutrophilic bronchitis, an increased risk of asthma diagnosis, asthma exacerbations and lower lung function.     

The effect of place of residence on access to invasive cardiac services following acute myocardial infarction

BACKGROUND:

The Canadian health care system is mandated to provide reasonable access to health care for all Canadians regardless of age, sex, race, socioeconomic status or place of residence. In the present study, the impact of place of residence in Nova Scotia on access to cardiac catheterization and long-term outcomes following an acute myocardial infarction (MI) were examined.

METHODS:

All patients with an acute MI who were hospitalized between April 1998 and December 2001 were identified. Place of residence was defined by postal code and separated into three categories: metropolitan area (MA); nonmetropolitan urban area (UA); and rural area (RA). Rates of and waiting times for cardiac catheterization were determined, as were risk-adjusted long-term rates of mortality and readmission to the hospital.

RESULTS:

A total of 7351 patients were hospitalized with an acute MI during the study period. Rates of cardiac catheterization differed across the three groups (MA 45.6%, UA 37.3%, RA 37.3%; P<0.0001), as did mean waiting times (MA 15.0 days, UA 32.1 days, RA 28.7 days) (P<0.0001). After adjusting for differences among patients, residence in either UA or RA emerged as an independent predictor of lower rates of cardiac catheterization (UA: hazard ratio [HR] 0.77, P<0.0001; RA: HR 0.75, P<0.0001), greater waiting times (UA: an additional 14.1 days, P<0.0001; RA: an additional 10.8 days, P<0.0001) and increased long-term rates of readmission (UA: HR 1.24, P=0.0001; RA: HR 1.12, P=0.04).

CONCLUSION:

In patients admitted with an acute MI, residence outside of an MA was associated with diminished rates of cardiac catheterization, longer waiting times and increased rates of readmission. Despite universal health care coverage, Canadians are subject to significant geographical barriers to cardiac catheterization with associated poorer outcomes.     

Effects of changes in lung volume on oscillatory flow rate during high-frequency chest wall oscillation

BACKGROUND:

The effectiveness of high-frequency chest wall oscillation (HFCWO) in mucolysis and mucous clearance is thought to be dependant on oscillatory flow rate (Fosc). Therefore, increasing Fosc during HFCWO may have a clinical benefit.

OBJECTIVES:

To examine effects of continuous positive airway pressure (CPAP) on Fosc at two oscillation frequencies in healthy subjects and patients with airway obstruction.

METHODS:

Five healthy subjects and six patients with airway obstruction underwent 12 randomized trials of HFCWO (CPAP levels of 0 cm H₂O, 2 cm H₂O, 4 cm H₂O, 6 cm H₂O, 8 cm H₂O and 10 cm H₂O at frequencies of 10 Hz and 15 Hz) within a body plethysmograph, allowing measurements of changes in lung volume. Fosc was measured by reverse plethysmography using a 20 L isothermic chamber near the mouth. At the end of each randomized trial, an inspiratory capacity manoeuvre was used to determine end-expiratory lung volume (EELV).

RESULTS:

EELV increased significantly (P<0.05) with each level of CPAP regardless of oscillation frequency. Fosc also significantly increased with CPAP (P<0.05) and it was correlated with EELV (r=0.7935, P<0.05) in obstructed patients but not in healthy subjects (r=0.125, P=0.343). There were no significant differences in perceived comfort across the levels of CPAP.

CONCLUSIONS:

Significant increases in Fosc with CPAP-induced increases in lung volume were observed, suggesting that CPAP may be useful as a therapeutic adjunct in patients who have obstructive airway disease and who require HFCWO.     

Mortality of elderly patients in Ontario after hospital admission for chronic obstructive pulmonary disease

BACKGROUND:

Chronic obstructive pulmonary disease (COPD) is associated with significant mortality. It is currently the fourth leading cause of death in Canada and the world.

OBJECTIVES:

To describe the mortality of elderly patients in Ontario after hospital admission for COPD.

METHODS:

A retrospective cohort study was conducted using the Discharge Abstract Database from the Canadian Institute for Health Information. Patients aged 65 years and older who were admitted to hospital between 2001 and 2004 with primary discharge diagnoses labelled with International Classification of Diseases, Ninth Revision codes 491, 492 and 496 were included in the study.

RESULTS:

Mortality rates were 8.81, 12.10, 14.53 and 27.72 per 100 COPD hospital admissions at 30, 60, 90 and 365 days after hospital discharge, respectively. Mortality also increased with age, and men had higher rates than women. No significant differences in mortality rates were found between different socioeconomic groups (P>0.05). Patients with shared care of a family physician or general practitioner and a specialist had significantly lower mortality rates than the overall rate (P<0.05), and their rates were approximately one-half the rate of patients with only one physician.

CONCLUSIONS:

Hospitalization with COPD is associated with significant mortality. Patients who were cared for by both a family physician or general practitioner and a specialist had significantly lower mortality rates than those cared for by only one physician, suggesting that continuous and coordinated care results in better survival.     

A randomized controlled trial to assess the efficacy of tiotropium in Canadian patients with chronic obstructive pulmonary disease

BACKGROUND:

Patients with chronic obstructive pulmonary disease (COPD) who smoke have a greater annual rate of decline in forced expiratory volume in 1 s (FEV₁) than those patients who have stopped smoking.

OBJECTIVES:

To assess the effect of tiotropium on pre-dose (trough) FEV₁ in patients with COPD followed in Canada.

METHODS:

A total of 913 patients were randomly assigned to receive either tiotropium 18 μg once daily (n=608) or placebo (usual care minus inhaled anticholinergics) (n=305) for 48 weeks in the present randomized, double-blind, parallel-group study. The effect of tiotropium on measurements of lung function (FEV₁, FEV₆ and forced vital capacity), symptoms, health-related quality of life (St George’s Respiratory Questionnaire) and exacerbations were examined.

RESULTS:

Tiotropium improved trough FEV₁ in both current and ex-smokers compared with placebo. Baseline FEV₁ in smokers and ex-smokers was 1.03 L and 0.93 L, respectively (P<0.001). At week 48, the mean difference between the tiotropium and placebo groups was 0.14±0.04 L (P<0.001) in the smoker group and 0.08±0.02 L (P<0.0001) in the ex-smoker group. Tiotropium also significantly improved trough forced vital capacity and FEV₆ compared with placebo throughout the treatment period (P<0.05, for all). Furthermore, tiotropium significantly improved the St George’s Respiratory Questionnaire total score compared with placebo at week 48 (40.9 versus 43.7 units, P<0.005).

CONCLUSIONS:

Compared with the placebo group, tiotropium provides sustained improvements in lung function in patients with COPD, with improvements for smokers and ex-smokers.     

Silent ischemia: Silent after all?

OBJECTIVE:

To examine the association of nonpain symptoms in men and women with exercise-related silent ischemia, as well as the independence of these findings from other clinical factors.

METHODS:

A prospective study of 482 women and 425 men (mean age 58 years) undergoing exercise stress testing with myocardial perfusion imaging. Analyses were performed on 60 women and 155 men with no angina but medical perfusion imaging evidence of ischemia during exercise.

MEASURES:

The presence of various non-pain-related symptoms. Ischemia is indicated by myocardial perfusion defects on exercise stress testing with single photon emission computed tomography.

RESULTS:

Women reported more nonangina symptoms than men (P<0.05). They experienced fatigue, hot flushes, tense muscles, shortness of breath and headaches more frequently (P<0.05). Symptoms relating to muscle tension and diaphoresis were associated with ischemia after controlling for pertinent clinical covariates. However, the direction of association differed according to sex and history of coronary artery disease events or procedures. Sensitivity of the detection models showed modest improvements with the addition of these symptoms.

CONCLUSIONS:

While patients who experience silent ischemia experience a number of nonpain symptoms, those symptoms may not be sufficiently specific to ischemia, nor sensitive in detecting ischemia, to be of particular help to physicians in the absence of other clinical information.     

Echocardiographic and electrocardiographic trends in children with acute Kawasaki disease

BACKGROUND:

Kawasaki disease (KD), while primarily an acute, self-limited, multisystem vasculitis, is more appropriately described as a pancarditis, from a cardiac perspective. Many patients are noted to have ventricular dilation on initial echocardiography; however, functional and structural measurements may remain within the normal range.

OBJECTIVE:

The authors sought to determine echocardiographic and electrocardiographic trends after acute KD.

METHODS:

Clinical data were reviewed on all patients presenting with acute KD to the Hospital for Sick Children (Toronto, Ontario). Patients with at least three electrocardiograms and echocardiograms over the first year post-KD were eligible. Mixed linear regression analysis for repeated measures was used to determine trends over time and associated factors.

RESULTS:

One hundred seventy-six eligible patients were reviewed. Mean initial coronary artery diameter Z-scores were increased, with 4% having aneurysms. The mean (± SD) initial Z-score of ejection fraction was 0.40±0.84 (P<0.001 versus normal) and left ventricular end-diastolic dimension (LVED) was 0.97±0.98 (P<0.001 versus normal). The initial mean QT dispersion was 54±23 ms (P<0.001 versus normal). Mixed linear regression analysis for repeated measures demonstrated that the LVED Z-score decreased significantly over time, and a greater Z-score was independently associated with a greater initial LVED Z-score. Increased QT dispersion was only related to higher initial dispersion, with no trend over time.

CONCLUSIONS:

While systolic ventricular dysfunction may not be evident, subclinical myocardial involvement may be indicated by subtle ventricular dilation and repolarization abnormalities.     

Paradoxical lower postmyocardial infarction mortality among veteran women – does a sex bias exist in the Veterans Affairs medical system?

BACKGROUND:

Outcomes after acute coronary disease are reportedly worse among women in general and more so among women with diabetes compared with men. Sex differences were evaluated in postmyocardial infarction (MI) mortality among veterans (who are predominantly male) to determine whether evaluation and treatment in Veterans Affairs hospitals amplifies sex differences in outcome.

METHODS:

All patients discharged with the primary diagnosis of acute MI from any Veterans hospitals in the United States between October 1990 and September 1997 were identified. Demographic, comorbidity, inpatient, outpatient, mortality and readmission data were extracted. Mortality, revascularization and readmissions were compared between male and female patients using Cox regression models.

RESULTS:

The authors identified 67,889 patients with MI, 17,756 (26%) of whom had diabetes. There were 951 women, 280 (29%) of whom had diabetes, and 66,938 men, 17,476 (26%) of whom had diabetes. Over the entire follow-up period, adjusted mortality was higher in men than women (hazard ratio [HR] 1.5, 95% CI 1.3 to 1.7). Cardiac procedures were significantly higher among men: HR for coronary bypass surgery was 2.1 (95% CI 1.6 to 2.8; P<0.001) for all men, while HR for catheterization and percutaneous coronary intervention were higher for men among non-diabetics only – 1.5 (95% CI 1.2 to 1.8; P<0.001) and 2.0 (95% CI 1.4 to 2.9; P<0.001). Interaction between sex and diabetes was not significant.

CONCLUSIONS:

Contrary to previous observations in the nonveteran population, long-term mortality post-MI was lower among veteran women, despite higher procedure rates in men. The present study also failed to show increased mortality in women with diabetes.