Immediate vs Delayed Stenting in ST-Elevation Myocardial Infarction: Rationale and Design of the International PRIMACY Bayesian Randomized Controlled Trial

BACKGROUND

Primary percutaneous coronary intervention is used to restore blood flow in the infarct-related coronary artery, followed by immediate stenting to prevent reocclusion. Stents implanted in thrombus-laden arteries cause distal embolization, which paradoxically impairs myocardial reperfusion and ventricular function. Whether a strategy of delayed stenting improves outcomes in patients with acute ST-elevation myocardial infarction (STEMI) is uncertain.

METHODS

The Primary Reperfusion Secondary Stenting (PRIMACY) is a Bayesian prospective, randomized, open-label, blinded end point trial in which delayed vs immediate stenting in patients with STEMI were compared for prevention of cardiovascular death, nonfatal myocardial infarction, heart failure, or unplanned target vessel revascularization at 9 months. All participants were immediately reperfused, but those assigned to the delayed arm underwent stenting after an interval of 24 to 48 hours. This interval was bridged with antithrombin therapy to reduce thrombus burden. In the principal Bayesian hierarchical random effects analysis, data from exchangeable trials will be combined into a study prior and updated with PRIMACY into a posterior probability of efficacy.

RESULTS

A total of 305 participants were randomized across 15 centres in France and Canada between April 2014 and September 2017. At baseline, the median age of participants was 59 years, 81% were male, and 3% had a history of percutaneous coronary intervention. Results from PRIMACY will be updated from the patient-level data of 1568 participants enrolled in the Deferred Stent Trial in STEMI (DEFER; United Kingdom), Minimalist Immediate Mechanical Intervention (MIMI; France), Danish Trial in Acute Myocardial Infarction-3 (DANAMI-3; Denmark), and Impact of Immediate Stent Implantation Versus Deferred Stent Implantation on Infarct Size and Microvascular Perfusion in Patients With ST Segment-Elevation Myocardial Infarction (INNOVATION, South Korea) trials.

CONCLUSIONS

We expect to clarify whether delayed stenting can safely reduce the occurrence of adverse cardiovascular end points compared with immediate stenting in patients with STEMI.

Antiphospholipid antibodies predict imminent vascular events independently from other risk factors in a prospective cohort

Antiphospholipid antibodies (aPL) are associated with vascular events, but the magnitude of this risk, alone, or in combination with other atherogenic and thrombophilic risk factors, remains unclear. A prospective cohort of 415 persons was studied for arterial and venous events (AE and VE) over a median time of 7.4 years. aPL and coagulation abnormalities were measured upon beginning of the study and annually for the first four years. Within the cohort, a nested case-control study was conducted to investigate the role of endothelial and inflammatory markers in predicting new vascular events. Forty-five individuals had new vascular events: 18 occurred during the first year of follow-up. The proportion of event-free survivors at eight years was 90% (95%CI = 87%, 94%) for aPL-negative and 72% (60%, 85%) for aPL-positive individuals, respectively. Predictors for new AE were previous AE (HR=5.7 [2.7, 12.0]), diabetes (5.6 [2.4, 13.2]), aPL positivity (2.6 ([1.2, 5.9]), and age (1.04 [1.01, 1.07]). New VE were predicted by previous VE (6.1 [1.9, 19.9]), anti-β2-glyco-protein I (aβ2GPI) positivity (5.8 [1.4, 24.1]), activated protein C resistance (APCR) (4.1 [1.1, 15.1]), and gender (3.7 [1.1, 12.9]). In the nested case-control study, similar predictors were observed for AE, while abnormal APCR (OR=5.5 [1.1, 26.6]) and elevated von Willebrand factor (vWF) (OR=5.0 [1.2, 19.8]) best predicted VE. We demonstrate that aPL independently predict new vascular events and discriminate between individuals with and without events in the first two years of follow-up, indicating that aPL are associated with a short-term risk of developing new and recurrent vascular events.

Electrocardiographic findings in systemic lupus erythematosus: data from an international inception cohort

OBJECTIVE

To estimate the early prevalence of various electrocardiographic (EKG) abnormalities in patients with systemic lupus erythematosus (SLE) and to evaluate possible associations between repolarization changes (increased corrected QT [QTc] and QT dispersion [QTd]) and clinical and laboratory variables, including the anti-Ro/SSA level and specificity (52 or 60 kd).

METHODS

We studied adult SLE patients from 19 centers participating in the Systemic Lupus International Collaborating Clinics (SLICC) Inception Registry. Demographics, disease activity (Systemic Lupus Erythematosus Disease Activity Index 2000 [SLEDAI-2K]), disease damage (SLICC/American College of Rheumatology Damage Index [SDI]), and laboratory data from the baseline or first followup visit were assessed. Multivariate logistic and linear regression models were used to asses for any cross-sectional associations between anti-Ro/SSA and EKG repolarization abnormalities.

RESULTS

For the 779 patients included, mean ± SD age was 35.2 ± 13.8 years, 88.4% were women, and mean ± SD disease duration was 10.5 ± 14.5 months. Mean ± SD SLEDAI-2K score was 5.4 ± 5.6 and mean ± SD SDI score was 0.5 ± 1.0. EKG abnormalities were frequent and included nonspecific ST-T changes (30.9%), possible left ventricular hypertrophy (5.4%), and supraventricular arrhythmias (1.3%). A QTc ≥440 msec was found in 15.3%, while a QTc ≥460 msec was found in 5.3%. Mean ± SD QTd was 34.2 ± 14.7 msec and QTd ≥40 msec was frequent (38.1%). Neither the specificity nor the level of anti-Ro/SSA was associated with QTc duration or QTd, although confidence intervals were wide. Total SDI was significantly associated with a QTc interval exceeding 440 msec (odds ratio 1.38 [95% confidence interval 1.06, 1.79]).

CONCLUSION

A substantial proportion of patients with recent-onset SLE exhibited repolarization abnormalities, although severe abnormalities were rare.

Rheumatoid arthritis prevalence in Quebec

BACKGROUND

To estimate rheumatoid arthritis (RA) prevalence in Quebec using administrative health data, comparing across regions.

METHODS

Cases of RA were ascertained from physician billing and hospitalization data, 1992-2008. We used three case definitions: 1) ≥ 2 billing diagnoses, submitted by any physician, ≥ 2 months apart, but within 2 years; 2) ≥ 1 diagnosis, by a rheumatologist; 3) ≥1 hospitalization diagnosis (all based on ICD-9 code 714, and ICD-10 code M05). We combined data across these three case definitions, using Bayesian hierarchical latent class models to estimate RA prevalence, adjusting for the imperfect sensitivity and specificity of the data. We compared urban versus rural regions.

RESULTS

Using our case definitions and no adjustment for error, we defined 75,760 cases for an over-all RA prevalence of 9.9 per thousand residents. After adjusting for the imperfect sensitivity and specificity of our case definition algorithms, we estimated Quebec RA prevalence at 5.6 per 1000 females and 4.1 per 1000 males. The adjusted RA prevalence estimates for older females were the highest for any demographic group (9.9 cases per 1,000), and were similar in rural and urban regions. In younger males and females, and in older males, RA prevalence estimates were lower in rural versus urban areas.

CONCLUSIONS

Without adjustment for error inherent in administrative databases, RA prevalence in Quebec was approximately 1%, while adjusted estimates are approximately half that. The lower prevalence in rural areas, seen for most demographic groups, may suggest either true regional variations in RA risk, or under-ascertainment of cases in rural Quebec.

Prevalence of systemic lupus erythematosus and systemic sclerosis in the First Nations population of Alberta, Canada

OBJECTIVE

To estimate the population-based prevalence of systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) in Alberta, Canada, stratified by First Nations status.

METHODS

Physician billing claims and hospitalization data for the province of Alberta (1994-2007) were used to ascertain cases of SLE and SSc using 3 case definitions. A latent class Bayesian hierarchical regression model was employed to account for the imperfect sensitivity and specificity of billing and hospitalization data in case ascertainment. We accounted for demographic factors, estimating prevalence rates for the First Nations and non-First Nations populations by sex, age group, and location of residence (urban/rural).

RESULTS

Our model estimated the prevalence of SLE in Alberta to be 27.3 cases per 10,000 females (95% credible interval [95% CrI] 25.9-28.8) and 3.2 cases per 10,000 males (95% CrI 2.6-3.8). The overall prevalence of SSc in Alberta was 5.8 cases per 10,000 females (95% CrI 5.1-6.5) and 1.0 case per 10,000 males (95% CrI 0.7-1.4). First Nations females over 45 years of age had twice the prevalence of either SLE or SSc relative to non-First Nations females. There was also a trend toward higher overall SLE prevalence in urban dwellers, and higher overall SSc prevalence in rural residents.

CONCLUSION

First Nations females older than 45 years of age have an increased prevalence of either SLE or SSc. This may reflect a true predominance of autoimmune rheumatic diseases in this demographic, or may indicate systematic differences in health care delivery.

Association of the Charlson comorbidity index with mortality in systemic lupus erythematosus

OBJECTIVE

To investigate whether comorbidity as assessed by the Charlson Comorbidity Index (CCI) is associated with mortality in a long-term followup of systemic lupus erythematosus (SLE) patients.

METHODS

Data were collected from 499 SLE patients attending the Lupus Clinic at the McGill University Health Center, Montreal, Quebec, Canada, and 170 SLE patients from the Department of Rheumatology at Lund University Hospital, Lund, Sweden. This included data on comorbidity, demographics, disease activity, the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI), and antiphospholipid antibody syndrome (APS). Variables were entered into a Cox proportional hazards survival model.

RESULTS

Mortality risk in the Montreal cohort was associated with the CCI (hazard ratio [HR] 1.57 per unit increase in the CCI, 95% confidence interval [95% CI] 1.18-2.09) and age (HR 1.04 per year increase in age, 95% CI 1.00-1.09). The CCI and age at diagnosis were also associated with mortality in the Lund cohort (CCI: HR 1.35, 95% CI 1.13-1.60; age: HR 1.09, 95% CI 1.05-1.12). Furthermore, the SDI was associated with mortality in the Lund cohort (HR 1.40, 95% CI 1.19-1.64), while a wide CI for the estimate in the Montreal cohort prevented a definitive conclusion (HR 1.20, 95% CI 0.97-1.48). We did not find a strong association between mortality and sex, race/ethnicity, disease activity, or APS in either cohort.

CONCLUSION

In this study, comorbidity as measured by the CCI was associated with decreased survival independent of age, lupus disease activity, and damage. This suggests that the CCI may be useful in capturing comorbidity for clinical research in SLE.

Features associated with cardiac abnormalities in systemic lupus erythematosus

OBJECTIVES

To determine the prevalence of echocardiographic abnormalities and identify associated clinical and laboratory features in a large systemic lupus erythematosus (SLE) cohort.

METHODS

Patients fulfilling ACR criteria for SLE underwent a transthoracic echocardiogram (TTE) between January 2005 and June 2006. Variables used as potential correlates included age, sex, ethnicity, lupus duration, lupus disease activity (SLEDAI), cumulative damage (SLICC/ACR damage index (DI)), arterial hypertension, diabetes, current smoking, medication use and laboratory data. Multivariate logistic regression was used to examine the association between TTE abnormalities and potential determinants.

RESULTS

For the 217 subjects with a TTE performed during the study, the main abnormalities were of the mitral valve (37.3%) and included thickening (25.4%) and insufficiency (25.8%). Other findings included pulmonary artery pressure (PAP)  ≥  30( )mm( )Hg (10.1%), pericardial effusion (4.6%), hypokinesis (2.8%), and aortic insufficiency (3.7%). In multivariate analysis, mitral insufficiency was associated with the use of corticosteroids (OR 2.90; 95%CI 1.42-5.94) and hypokinesis with angiotensin-converting enzyme inhibitors (12.89; 1.06-157.18). Elevated PAP was associated with age (1.04; 1.01-1.07) and with DI (1.20; 1.01-1.42).

CONCLUSION

Valvular abnormalities are frequent in patients with SLE, with mitral valve lesions occurring in over one third. TTE screening may be indicated in patients with SLE, especially for those with identified risk factors such as corticosteroid use.

Prolonged corrected QT interval in anti-Ro/SSA-positive adults with systemic lupus erythematosus

OBJECTIVE

To examine whether anti-Ro/SSA antibodies are associated with an increased risk of corrected QT (QTc) prolongation, and to study the stability of this relationship over time.

METHODS

Patients fulfilling the American College of Rheumatology (ACR) criteria for systemic lupus erythematosus (SLE) were invited to undergo a 12-lead resting electrocardiogram (EKG) in the pilot phase of our project, performed between February 2002 and March 2005. The same study population was used to perform a second similar analysis with a larger sample between April 2005 and May 2007. Multivariate logistic regression models were fit to estimate the cross-sectional association between anti-Ro/SSA and other demographic and clinical variables on QTc prolongation. The other potentially associated factors examined included age, sex, disease duration, lupus activity (Systemic Lupus Erythematosus Disease Activity Index 2000 update), damage (Systemic Lupus International Collaborating Clinics/ACR Damage Index), potassium and magnesium levels, and medications with the potential to prolong the QTc interval.

RESULTS

Cross-sectional analysis of the pilot data (n = 150 patients) showed an association of prolonged QTc with the presence of anti-Ro/SSA (adjusted odds ratio [OR] 12.6; 95% confidence interval [95% CI] 2.3, 70.7). In the second larger study (n = 278), the association was replicated, with a narrower 95% CI (adjusted OR 5.1; 95% CI 1.5, 17.4). In the 118 patients with 2 EKG assessments, the results were consistent over time.

CONCLUSION

Anti-Ro/SSA was associated with QTc prolongation in both our pilot data and a larger SLE cohort sample. Patients positive for anti-Ro/SSA may benefit from EKG testing and appropriate counseling should be considered for those identified with QTc prolongation.

Polymyalgia rheumatica prevalence in a population-based sample

OBJECTIVE

To determine polymyalgia rheumatica (PMR) prevalence using population-based administrative data, and to estimate the error associated with case ascertainment approaches when using these databases.

METHODS

Cases were ascertained using physician billing and hospitalization data from the province of Manitoba (population 1.1 million). Focusing on the population age >/=45 years, we compared 3 different case definition algorithms and also used statistical methods that accounted for imperfect case ascertainment to estimate the prevalence and the properties of the ascertainment algorithms. A hierarchical Bayesian latent class regression model was developed that also allowed us to assess differences across patient demographics (sex and region of residence).

RESULTS

Using methods that account for the imperfect nature of both billing and hospitalization databases, we estimated the prevalence of PMR in women age >/=45 years to be lower in urban areas (754.5 cases/100,000; 95% credible interval [95% CrI] 674.1-850.3) compared with rural areas (1,004 cases/100,000; 95% CrI 886.3-1,143). This regional trend was also seen in men age >/=45 years, where the prevalence was estimated at 273.6 cases/100,000 (95% CrI 219.8-347.6) in urban areas and 380.7 cases/100,000 (95% CrI 311.3-468.1) in rural areas. Billing data appeared more sensitive in ascertaining cases than hospitalization data, and a large proportion of diagnoses was made by physicians other than rheumatologists.

CONCLUSION

These data suggest a higher prevalence of PMR in rural versus urban regions. Our approach demonstrates the usefulness of methods that adjust for the imperfect nature of multiple information sources, which also allow for estimation of the sensitivity of different case ascertainment approaches.

Scleroderma prevalence: demographic variations in a population-based sample

OBJECTIVE

To estimate the prevalence of systemic sclerosis (SSc) using population-based administrative data, and to assess the sensitivity of case ascertainment approaches.

METHODS

We ascertained SSc cases from Quebec physician billing and hospitalization databases (covering approximately 7.5 million individuals). Three case definition algorithms were compared, and statistical methods accounting for imperfect case ascertainment were used to estimate SSc prevalence and case ascertainment sensitivity. A hierarchical Bayesian latent class regression model that accounted for possible between-test dependence conditional on disease status estimated the effect of patient characteristics on SSc prevalence and the sensitivity of the 3 ascertainment algorithms.

RESULTS

Accounting for error inherent in both the billing and the hospitalization data, we estimated SSc prevalence in 2003 at 74.4 cases per 100,000 women (95% credible interval [95% CrI] 69.3-79.7) and 13.3 cases per 100,000 men (95% CrI 11.1-16.1). Prevalence was higher for older individuals, particularly in urban women (161.2 cases per 100,000, 95% CrI 148.6-175.0). Prevalence was lowest in young men (in rural areas, as low as 2.8 cases per 100,000, 95% CrI 1.4-4.8). In general, no single algorithm was very sensitive, with point estimates for sensitivity ranging from 20-73%.

CONCLUSION

We found marked differences in SSc prevalence according to age, sex, and region. In general, no single case ascertainment approach was very sensitive for SSc. Therefore, using data from multiple sources, with adjustment for the imperfect nature of each, is an important strategy in population-based studies of SSc and similar conditions.

Antiphospholipid antibodies predict imminent vascular events independently from other risk factors in a prospective cohort

Antiphospholipid antibodies (aPL) are associated with vascular events, but the magnitude of this risk, alone, or in combination with other atherogenic and thrombophilic risk factors, remains unclear. A prospective cohort of 415 persons was studied for arterial and venous events (AE and VE) over a median time of 7.4 years. aPL and coagulation abnormalities were measured upon beginning of the study and annually for the first four years. Within the cohort, a nested case-control study was conducted to investigate the role of endothelial and inflammatory markers in predicting new vascular events. Forty-five individuals had new vascular events: 18 occurred during the first year of follow-up. The proportion of event-free survivors at eight years was 90% (95%CI = 87%, 94%) for aPL-negative and 72% (60%, 85%) for aPL-positive individuals, respectively. Predictors for new AE were previous AE (HR = 5.7 [2.7, 12.0]), diabetes (5.6 [2.4, 13.2]), aPL positivity (2.6 ([1.2, 5.9]), and age (1.04 [1.01, 1.07]). New VE were predicted by previous VE (6.1 [1.9, 19.9]), anti-beta2-glycoprotein I (abeta2GPI) positivity (5.8 [1.4, 24.1]), activated protein C resistance (APCR) (4.1 [1.1, 15.1]), and gender (3.7 [1.1, 12.9]). In the nested case-control study, similar predictors were observed for AE, while abnormal APCR (OR = 5.5 [1.1, 26.6]) and elevated von Willebrand factor (vWF) (OR = 5.0 [1.2, 19.8]) best predicted VE. We demonstrate that aPL independently predict new vascular events and discriminate between individuals with and without events in the first two years of follow-up, indicating that aPL are associated with a short-term risk of developing new and recurrent vascular events.

Socioeconomic status, access to health care, and outcomes after acute myocardial infarction in Canada's universal health care system

BACKGROUND

There is a debate as to whether universal drug coverage confers similar access to care at all socioeconomic status (SES) levels. Experiences in Canada may bring light to questions raised regarding access.

OBJECTIVE

To assess associations between SES and access to cardiac care and outcomes in Canada's universal health care system.

DESIGN, SETTING, AND PATIENTS

All patients admitted to acute care hospitals in Quebec (QC), Ontario (ON), and British Columbia (BC), between 1996 and either 2000 (QC) or 2001 (ON, BC) with acute myocardial infarction, were identified using provincial government administrative databases (n = 145,882).

MEASUREMENTS

Variables representing SES grouped at the census area level were examined in association with use of cardiac medications and procedures, survival, and readmission, while adjusting for individual-level variables. A Bayesian hierarchical logistic regression model was used to account for the nested structure of the data.

RESULTS

Despite provincial variations in SES and drug reimbursement policies, there were generally no associations between the SES variables and access to cardiac medications or invasive cardiac procedures. The few exceptions were not consistent across SES indicators and/or provinces. Similarly, the only observed effect of SES on clinical outcomes was in BC, where there was increased 1-year mortality among patients living in less-affluent regions (adjusted odds ratios per standard deviation change in proportion of low-income households, 95% Bayesian credible intervals, QC: 1.09, 0.96-1.25; ON: 1.02, 0.95-1.08; and BC: 1.18, 1.09-1.28).

CONCLUSIONS

These results suggest that intermediary factors other than SES, such as cardiovascular risk factors, likely account for observed "wealth-health" gradients in Canada. Implementation of a universal drug coverage policy could decrease socioeconomic disparities in access to health care.

Bayesian change-point analyses in ecology

Ecological and biological processes can change from one state to another once a threshold has been crossed in space or time. Threshold responses to incremental changes in underlying variables can characterize diverse processes from climate change to the desertification of arid lands from overgrazing. Simultaneously estimating the location of thresholds and associated ecological parameters can be difficult: ecological data are often 'noisy', which can make the identification of the locations of ecological thresholds challenging. We illustrate this problem using two ecological examples and apply a class of statistical models well-suited to addressing this problem. We first consider the case of estimating allometric relationships between tree diameter and height when the trees have distinctly different growth modes across life-history stages. We next estimate the effects of canopy gaps and dense understory vegetation on tree recruitment in transects that transverse both canopy and gap conditions. The Bayesian change-point models that we present estimate both threshold locations and the slope or level of ecological quantities of interest, while incorporating uncertainty in the change-point location into these estimates. This class of models is suitable for problems with multiple thresholds and can account for spatial or temporal autocorrelation.

The persistence of anticardiolipin antibodies is associated with an increased risk of the presence of lupus anticoagulant and anti-beta2-glycoprotein I antibodies

OBJECTIVE

We studied antiphospholipid antibodies (aPL) in blood samples from a cohort of individuals followed for thrombosis to determine whether the persistent presence of anticardiolipin antibodies (aCL) is associated with a greater likelihood of having lupus anticoagulant and/or anti-beta2-glycoprotein I antibodies (LA/abeta2GPI).

METHODS

Blood samples from 353 individuals who had been tested for aCL on at least two occasions were tested for abeta2GPI and LA. Two groups were defined: aCL-persistent, who tested aCL-positive on at least two occasions, and aCL non-persistent, who tested aCL-positive on fewer than two occasions. Multivariate logistic regressions were performed using LA/abeta2GPI, LA and abeta2GPI as outcome variables and the percentage of aCL-positive tests as the predictor variable, adjusted for age, gender, family history of cardiovascular disease (CVD), systemic lupus erythematosus (SLE), smoking and number of venous (VT) and arterial thromboses (AT).

RESULTS

Sixty-eight (19%) individuals were aCL persistent and 285 (81%) were aCL non-persistent. LA/abeta2GPI was found in 36 (53%) of the aCL persistent group and 38 (13%) of the aCL non-persistent group. The two groups were similar for age, gender and smoking. Family history of CVD, SLE, VT and AT were more frequent in the aCL persistent group. Multivariate analyses revealed that odds ratios for LA/abeta2GPI, LA and abeta2GPI were 1.34 [95% confidence interval (CI) = 1.22-1.47], 1.36 (95% CI = 1.24-1.50) and 1.47 (95% CI = 1.31-1.65) respectively for each 10% increase in aCL-positive tests vs 0% positive tests.

CONCLUSION

Persistence of aCL positivity is associated with an increased risk of LA/abeta2GPI.

Effect of Delay in Initiating Radiotherapy for Patients with Early Stage Breast Cancer

AIMS

For early stage breast cancer, a standard treatment option is partial mastectomy followed by radiation treatment. The 5-year risk of local recurrence ranges from 6-9%. Variable waiting times for radiation treatment of breast cancer in our institution provided an opportunity to evaluate the impact of waiting time on the risk of local recurrence.

MATERIALS AND METHODS

Between January 1988 and December 1989, 482 patients with stage I and II breast cancer were treated with radiotherapy in our institution. Information on prognostic factors, such as age, tumour size, histological grade, number of positive lymph nodes and margins of resection, was abstracted from their charts. The interval between date of surgery and date of initial radiation treatment was noted. Dates of local recurrence, metastasis and deaths were recorded.

RESULTS

At 5 years, the local recurrence rate was 8%, the metastatic rate 12% and the 'cause-specific' survival rate 90%. In univariate analysis, the risk of local recurrence was associated with younger age, higher histological grade and time to radiation treatment. In the multivariate analysis, the effect of time to radiation treatment on the risk of local recurrence was equivocal.

CONCLUSION

Delay in radiation treatment may be associated with an increased risk of local recurrence of breast cancer, at least in our centre. Future research is needed on a larger data set to more accurately estimate the effect of time to radiation treatment on the risk of local recurrence.

Evidence for use of coronary stents. A hierarchical bayesian meta-analysis

BACKGROUND

Coronary stents are widely used in interventional cardiology, but a current quantitative systematic overview comparing routine coronary stenting with standard percutaneous transluminal coronary angioplasty (PTCA) and restricted stenting (provisional stenting) has not been published.

PURPOSE

To summarize results from all randomized clinical trials comparing routine coronary stenting with standard PTCA.

DATA SOURCES

Electronic databases were searched by using the key words angioplasty and stent. References from identified articles were also reviewed. In addition, several prominent general medical and cardiology journals were searched and agencies known to perform systematic reviews were consulted.

STUDY SELECTION

All comparative randomized clinical trials were included, except those involving primary angioplasty for the treatment of acute myocardial infarction.

DATA EXTRACTION

A specified protocol was followed, and two of the authors independently extracted the data. Outcomes assessed were total mortality, myocardial infarction, angiographic restenosis, coronary artery bypass surgery, repeated PTCA, and freedom from angina.

DATA SYNTHESIS

The results were synthesized by using a Bayesian hierarchical random-effects model. A total of 29 trials involving 9918 patients were identified. There was no evidence for a difference between routine coronary stenting and standard PTCA in terms of deaths or myocardial infarctions (odds ratio, 0.90 [95% credible interval [CrI], 0.72 to 1.11]) or the need for coronary artery bypass surgery (odds ratio, 1.01 [CrI, 0.79 to 1.31]). Coronary stenting reduced the rate of restenosis (odds ratio, 0.52 [CrI, 0.37 to 0.69]) and the need for repeated PTCA (odds ratio, 0.59 [CrI, 0.50 to 0.68]). The trials showed a wide range of crossover rates from PTCA to stenting. By use of a multiplicative model, each 10% increase in crossover rate decreased the need for repeated angioplasty by approximately 8% (odds ratio multiplying factor, 1.08 [CrI, 0.98 to 1.18]). Routine stenting probably reduces the need for repeated angioplasty by fewer than 4 to 5 per 100 treated persons compared with PTCA with provisional stenting. Studies were not blinded and suggest a bias with a possible overestimation of this benefit.

CONCLUSIONS

In the controlled environment of randomized clinical trials, routine coronary stenting is safe but probably not associated with important reductions in rates of mortality, acute myocardial infarction, or coronary artery bypass surgery compared with standard PTCA with provisional stenting. Coronary stenting is associated with substantial reductions in angiographic restenosis rates and the subsequent need for repeated PTCA, although this benefit may be overestimated because of trial designs. The incremental benefit of routine stenting for reducing repeated angioplasty diminishes as the crossover rate of stenting with conventional PTCA increases.

TOLERATED CO-FEEDING IN RELATION TO DEGREE OF KINSHIP IN JAPANESE MACAQUES

Abstract

We analyzed co-feeding in relation to degree of kinship in Japanese macaques Macaca fuscata), testing experimentally five categories of matrilineal kin dyads: mother-daughter, grandmother-granddaughter, sisters, aunt-niece and nonkin. In each test, two adult females with a clear dominance relationship had access to a box containing a limited quantity of highly prized food. The dominant female could easily prevent the subordinate from eating so that food was easily monopolizable, hence the use of the expression tolerated co-feeding. Rates of tolerated co-feeding increased steeply with degree of kinship. The aggression levels of dominant females towards subordinate females decreased with increasing degree of kinship and this effect was most apparent between mothers and daughters. The confidence level of subordinate females increased with degree of kinship and this effect became apparent above the aunt-niece kin class. Prior access to food by the subordinate female was a significant means of access to food, mostly beyond the grandmother-granddaughter kin category. The results point to a relatedness threshold for the preferential treatment of kin at r = 0.25 (grandmother-granddaughter and sister dyads), beyond which (r = 0.125: aunt-niece dyads), levels of tolerated co-feeding were comparable to those of nonkin females. The identity of this threshold with that found in previous studies on the same group for two different types of interactions suggests the existence of a generalized relatedness threshold for kin favoritism in Japanese macaques. Assuming that the costs of food defense by the dominant females were negligible and that tolerated co-feeding was altruistic, our results support the role of kin selection in the evolution of altruism in primates beyond the mother-offspring bond.

Learning from discordance in patient and physician global assessments of systemic lupus erythematosus disease activity

OBJECTIVE

Differences have been described between patient and physician assessments of well being in several chronic illnesses, and these differences may affect outcome. Disagreement may lead to dissatisfaction and to behaviors with dangerous consequences. We describe and identify predictors of patient-physician differences on ratings of disease activity in systemic lupus erythematosus (SLE).

METHODS

Data collected on 154 patients included age, education, disease duration, and patient and physician global assessments of lupus activity on a 10 cm visual analog scale (VAS), the Health Assessment Questionnaire (HAQ), the Medical Outcome Study Short-Form 36 (SF-36), the Systemic Lupus Disease Activity Index (SLEDAI), the Systemic Lupus Activity Measure (SLAM-R), and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). Multiple linear regression models were performed using patient VAS scores, physician VAS scores, and patient minus physician VAS scores as the dependent variables, and age, disease duration, selected SF-36 and SLAM-R subscales, and SDI as independent variables.

RESULTS

Patients were 90% female and 80% Caucasian, with a mean education of 13 +/- 2.8 years and a mean age of 43.1 +/- 13.6 years. The overall mean disease duration was 10.5 +/- 7.8 years. Physicians overscored patients by 2.5 cm in 6% of the cases and patients overscored physicians in 16% of the cases. The best multivariate model to predict overall differences included SF-36 mental health and SLAM-R kidney scores.

CONCLUSION

Patient-physician differences may result from a divergence in focus. Patients score lupus activity based on their psychological status, while physicians rely more heavily on the physical effect of the disease.