Previous studies have indicated that sex differences may exist in the pharmacological management of acute myocardial infarction (AMI), with female patients being treated less aggressively.
To determine if previously reported sex differences in AMI medication use were also evident among all AMI patients treated at hospitals in an urban Canadian city.
All patients who had a primary discharge diagnosis of AMI from all three adult care hospitals in Calgary, Alberta, in the 1998/1999 fiscal year were identified from hospital administrative records (n=914). A standardized, detailed chart review was conducted. Information collected from the medical charts included sociodemographic and clinical characteristics, comorbid conditions, and cardiovascular medication use during hospitalization and at discharge.
Similar proportions of female and male patients were treated with thrombolytics, beta-blockers, angiotensin-converting enzyme inhibitors, nitrate, heparin, diuretics and digoxin. Among patients aged 75 years and over, a smaller proportion of female patients received acetylsalicylic acid in hospital than did male patients (87% versus 95%; P=0.026). Multivariable logistic regression analysis revealed that, after correction for age, use of other anticoagulants/antiplatelets and death within 24 h of admission, sex was no longer an independent predictor for receipt of acetylsalicylic acid in hospital. Medications prescribed at discharge were similar between male and female patients.
The results from this Canadian chart review study, derived from detailed clinical data, indicate that the pattern of pharmacological treatment of female and male AMI patients during hospitalization and at discharge was very similar. No sex differences were evident in the treatment of AMI among patients treated in an urban Canadian centre.
Logistic regression models are frequently used in cohort studies to determine the association between treatment and dichotomous outcomes in the presence of confounding variables. In a logistic regression model, the association between exposure and outcome is measured using the odds ratio (OR). The OR can be difficult to interpret and only approximates the relative risk (RR) in certain restrictive settings. Several authors have suggested that for dichotomous outcomes, RRs, RR reductions, absolute risk reductions, and the number needed to treat (NNT) are more clinically meaningful measures of treatment effect.
We describe a method for deriving clinically meaningful measures of treatment effect from a logistic regression model. This method involves determining the probability of the outcome if each subject in the cohort was treated and if each subject was untreated. These probabilities are then averaged across the study cohort to determine the average probability of the outcome in the population if all subjects were treated and if they were untreated.
Risk differences, RRs, and NNTs were derived using a logistic regression model.
Clinically meaningful measures of effect can be derived from a logistic regression model in a cohort study. These methods can also be used in randomized controlled trials when logistic regression is used to adjust for possible imbalance in prognostically important baseline covariates.
Previous studies comparing percutaneous coronary intervention (PCI) with thrombolysis for treatment of myocardial infarction with ST-elevation have in meta-analyses but not in randomized trials shown that PCI is more effective. Despite a large volume of primary PCI performed in Sweden no controlled trials have been carried out. The present study included 96 patients with myocardial infarction with ST-segment elevation treated with primary PCI 1995-1998. The main indications were shock (15 cases), contraindication to thrombolysis (24 cases), as an alternative to thrombolysis (57 cases), with a mortality in the respective groups of 67, 25 and 10 percent. Controls matched for age and infarct location and treated with thrombolysis could be identified for 55 of the patients treated with PCI. After four years 40 percent and 52 percent of the patients treated with PCI and thrombolysis respectively reached the combined endpoint of death/myocardial infarction/revascularization/angina pectoris (not significant). In conclusion, the study shows that primary PCI in patients with myocardial infarction with ST-segment elevation can be performed safely also in Sweden.
Occluded coronary arteries should be opened urgently in patients who have acute myocardial infarction and ST-elevation in ECG. When transport times are long, thrombolytic treatment is a good alternative to primary percutaneous coronary intervention (PCI). The purpose of this study was to assess choice of treatment strategy in cases where time after start of symptoms and transport time are decisive for the outcome.
A cohort study of 379 patients, who had myocardial infarction and ST-elevation, and were admitted to St. Olav's Hospital, Trondheim, Norway in the period 1.11.2007-31.1.2009.
268 patients (71 %) were treated with PCI, and 111 patients (29 %) with thrombolytic treatment. 173 patients (46 %) were transported by helicopter. The counties in Mid-Norway used markedly different treatment strategies for these patients.
Great regional differences were observed in the use of PCI and thrombolytic treatment in Mid-Norway.
OBJECTIVE: Acute Myocardial Infarction (AMI) is a rising epidemic in developing countries. While studies in the West have established the characteristics and management of AMI patients, comprehensive data reflecting these issues in the Pakistani subjects is scarce. This study examined the profile and management of AMI in patients hospitalized at a tertiary care hospital in Karachi, Pakistan. METHODS: Three hundred forty four patients admitted in 1998 with the diagnosis of AMI met our inclusion criteria. Data on presentation, investigations, monitoring and therapy was obtained. Chi-square and t tests were used to analyze the data. RESULTS: Out of 344 patients with AMI, 71% were males; 58% had a Q wave MI. Majority of the patients who presented within 2 hours of symptom onset (36%), had chest pain. Patients with dyspnea and no chest pain were more likely to present after 12 hours of the onset of symptoms. In-house mortality was found to be 10.8%. Low HDL and diabetes was associated with in-hospital complications. Twenty nine percent of patients were given thrombolytic therapy with a mean door-to-needle time of 1 hour 36 minutes; 33% of patients who were eligible of Streptokinase did not receive it. Cardiac catheterization was performed in 28% patients. Echocardiography and Exercise Tolerance Test, both under utilized, were performed in 67% and 16% of patients, respectively. Two hundred sixteen (70%) patients discharged from hospital were contacted via telephone and the 1-year mortality rate among them was 28%. CONCLUSION: The profile and management of AMI was in coherence with earlier, Western studies. Chest pain units need to be established in the Emergency Room. Patients should be risk stratified prior to discharge. Public awareness regarding primary and secondary prevention and symptoms of AMI needs to be increased.
Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 1620 Tremont St (Ste 3030), Boston, MA 02120, USA. email@example.com
To evaluate the effects of patient copayment and coinsurance policies on adherence to therapy with beta-adrenergic blocking agents (beta-blockers) and on the rate of initiation of beta-blocker therapy after acute myocardial infarction (MI) in a population-based natural experiment.
Three sequential cohorts included British Columbia residents age 66 years and older who initiated beta-blocker therapy during time intervals with full drug coverage (2001), a $10 or $25 copayment (2002), and 25% coinsurance (2003-2004). We used linked data on all prescription drug dispensings, physician services, and hospitalizations. Follow-up of each cohort was 9 months after the policy changes.
We measured the proportion of subjects in each cohort who were adherent to beta-blocker therapy over time, with adherence defined as having >80% of days covered. We also measured the proportion of patients initiating beta-blocker therapy after acute MI. Policy effects were evaluated using multivariable regression.
Adherence to beta-blocker therapy was marginally reduced as a consequence of the copayment policy (-1.3 percentage points, 95% confidence interval [CI] = -2.5 , -0.04) or the coinsurance policy (-0.8 percentage points, 95% CI = -2.0, 0.3). The proportion of patients initiating beta-blockers after hospitalization for acute MI remained steady at about 61% during the study period, similar to that observed in a control population of elderly Pennsylvania residents with full drug coverage.
Fixed patient copayment and coinsurance policies had little negative effect on adherence to relatively inexpensive beta-blocker therapy, or initiation of beta-blockers after acute MI.
Cites: N Engl J Med. 1991 Oct 10;325(15):1072-71891009
Population studies of statin adherence are generally restricted to one to two years of follow-up and do not analyze adherence to other drugs.
To report long-term adherence rates for statins, angiotensin-converting enzyme (ACE) inhibitors and beta-blockers in patients who recently experienced a first cardiovascular event.
Linked administrative databases in the province of Saskatchewan were used in this retrospective cohort study. Eligible patients received a new statin prescription within one year of their first cardiovascular event between 1994 and 2001. Adherence to statins, beta-blockers and ACE inhibitors was assessed from the first statin prescription to a subsequent cardiovascular event.
Of 1221 eligible patients, the proportion of patients adherent to statin medications dropped to 60.3% at one year and 48.8% at five years. The decline in the proportion of adherent patients was most notable during the first two years (100% to 53.7%). Several factors were associated with statin adherence, including age (P = 0.012), number of physician service days (P = 0.037), chronic disease score (P = 0.032), beta-blocker adherence (P
Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 1620 Tremont St, Suite 3030, Boston, MA 02120, USA. firstname.lastname@example.org
As medication spending grows, Medicare Part D will need to adapt its coverage policies according to emerging evidence from a variety of insurance policies. We sought to evaluate the consequences of copayment and coinsurance policies on the initiation of statin therapy after acute myocardial infarction and adherence to therapy in statin initiators using a natural experiment of all British Columbia residents aged 66 years and older.
Three consecutive cohorts that included all patients who began statin therapy during full drug coverage (2001), coverage with a $10 or $25 copay (2002), and coverage with a 25% coinsurance benefit (2003-2004) were followed up with linked healthcare utilization data (n=51,561). Follow-up of cohorts was 9 months after each policy change. Adherence to statin therapy was defined as > or = 80% of days covered. Relative to full-coverage policies, adherence to new statin therapy was significantly reduced, from 55.8% to 50.5%, under a fixed copayment policy (-5.4% points; 95% CI, -6.4% to -4.4%) and the subsequent coinsurance policy (-5.4% points; 95% CI, -6.3% to -4.4%). An uninterrupted increase in the proportion of patients initiating statin therapy after an acute myocardial infarction (1.7% points per quarter) was observed over the study period, similar to a Pennsylvania control population with full coverage. Sudden changes to full out-of-pocket spending, similar to Medicare's Part D "doughnut hole," almost doubled the risk of stopping statins (adjusted odds ratio, 1.94, 95% CI, 1.82 to 2.08).
Fixed patient copayment and coinsurance policies have negative effects on adherence to statin lipid-lowering drug therapy but not on their initiation after myocardial infarction.