Outcomes following coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in the stent era: a prospective study of all 9890 consecutive patients operated on in Scotland over a two year period

Record linkage in Scotland and its applications to health research

AIMS AND OBJECTIVES

  This paper will focus on the key concepts behind record linkage and describe how probability matching of Scottish health records can be used for national health research.

BACKGROUND

  Record linkage can bring together two or more records relating to the same individual. This allows information from multiple sources to be joined together to produce richer data sets for research purposes and has wide applicability in public health and epidemiological research. The probability matching techniques underpinning record linkage bring together records on a patient basis using key identifying information on each record. Scotland has a strong track record for performing linkage for research purposes owing to routinely collected and well-maintained national administrative health data sets, the emergence of the Scottish record linkage system and organisations like the Information Services Division of NHS National Services Scotland who centrally hold permanently linked patient-based databases. Design.  A record linkage retrospective population cohort study is described within this paper.

METHODS

  The paper will describe current linkage methodology before discussing typical applications in the setting of Information Services Division and focusing on a particular linkage study investigating rates and risk factors for gastroschisis.

RESULTS

  Conclusions from the gastroschisis study are typical of the types of important findings drawn from analysing linked health data.

CONCLUSIONS

  Scotland's good track record for linking records for health research is evidenced by the high volume of research projects, publications and findings resulting from probability matching of national health data. Relevance to clinical practice.  Record linkage allows information relating to the same person held across different data sources to be brought together. Probabilistic record linkage can overcome data quality issues, producing accurate matches. This allows linked, analysable, patient-based databases, capable of answering complex research questions, to be produced from several data sources with wide applications in the field of health research.

Declining in-hospital mortality in patients undergoing coronary bypass surgery in the United States irrespective of presence of type 2 diabetes or congestive heart failure

BACKGROUND

Significant advances in surgical techniques and postsurgical care have been made in the last 10 years. The goal of this study was to evaluate any decline in the age-adjusted in-hospital mortality rate of patients undergoing coronary artery bypass grafting (CABG) using a national database from 1989 to 2004 in the United States.

HYPOTHESIS

Reduction in CABG related mortality in recent years.

METHODS

Using the Nationwide Inpatient Sample (NIS) database, we obtained specific ICD-9-CM codes forCABG to compile the data. To exclude nonatherosclerotic cause of coronary disease, we studied only patients older than 40 years. We calculated total and age-adjusted mortality rate per 100,000 for this period.

RESULTS

The NIS database contained 1 145 285 patients who had CABG performed from 1988 to 2004. The mean age for these patients was 71.05 ± 9.20 years. From 1989, the age-adjusted rate for all CABG-related mortality has been decreasing steadily and reached the lowest level in 2004: 300.3 per 100 000 in 1989, (95%confidence interval [CI], 20.4-575.9) and 104.69 per 100 000 (95% CI, 22.6-186.7) in 2004. Total death also declined from 5.5% to 3.06%. This decline occurred irrespective of comorbidities such as congestive heart failure, diabetes, or acute myocardial infarction, albeit increasing the number of CABG procedures performed in high-risk patients.

CONCLUSIONS

The age-adjusted in-hospital mortality rate from CABG has been declining steadily and reached its lowest level in 2004, irrespective of comorbidities. This decline most likely reflects advances in surgical techniques and the use of evidence-based medicine in patients undergoing CABG.

Anxiety in patients undergoing percutaneous coronary interventions

OBJECTIVE

Many patients undergoing percutaneous coronary intervention (PCI) experience symptoms of anxiety; however, it is unclear whether anxiety is an issue in the early recovery period and the types of factors and patient concerns that are associated. This study set out to determine the patterns of anxiety and concerns experienced by patients undergoing PCI and the contributing factors in the time period surrounding PCI.

METHODS

A convenience sample of patients undergoing PCI (n = 100) were recruited, and anxiety was measured using the Spielberger State Anxiety Inventory immediately before the PCI, the first day postprocedure, and 1 week postdischarge. Patients were also asked to identify their most important concern at each time. Independent predictors of anxiety at each time were determined by multiple regression analysis.

RESULTS

Anxiety scores were highest pre-procedure (35.72, standard deviation [SD] 11.75), decreasing significantly by the postprocedure time (31.8, SD 10.20) and further still by the postdischarge time (28.79, SD 9.78) (repeated-measures analysis of variance: F = 39.72, P < .001). The concerns patients identified most frequently as most important were the outcome of the PCI and the possibility of surgery pre-procedure (37%) and postdischarge (31%), and the limitations and discomfort arising from the access site wound and immobility postprocedure (25%). The predictor of anxiety at the pre-procedure time was taking medication for anxiety and depression (b = 7.12). The predictors of anxiety at the postprocedure time were undergoing first-time PCI (b = 4.44), experiencing chest pain (b = 7.63), and experiencing pre-procedural anxiety (b = .49). The predictors of anxiety at the postdischarge time were reporting their most important concern as the future progression of CAD (b = 7.51) and pre-procedural anxiety (b = .37).

CONCLUSION

Symptoms of anxiety were common, particularly before PCI. These symptoms are important to detect and treat because pre-procedural anxiety is predictive of anxiety on subsequent occasions. Patients who have had chest pain or their first PCI should be targeted for intervention during the early recovery period after PCI, and information on CAD should be provided postdischarge.

Value of early cardiac troponin I to predict long-term adverse events after coronary artery bypass graft surgery in patients presenting with acute coronary syndromes

BACKGROUND

High values of both preoperative and postoperative cardiac troponin I (cTnI) contribute to higher rates of short-term cardiac events following coronary artery bypass graft (CABG) surgery in patients with acute coronary syndrome (ACS). The prognostic value of very early cTnI in this context is unclear.

HYPOTHESIS

Measurement of cTnI very early after admission to the emergency room can be used as a prognosticator for long-term outcomes after CABG.

METHODS

We conducted a cohort study on 160 consecutive patients with ACS undergoing CABG at The John H. Stroger Jr. Hospital of Cook County (Chicago, IL) representing a total follow-up of 290.42 person-years. Adverse outcomes were defined as death or reinfarction. We used robust multivariate survival analyses to determine whether early cTnI measurement can independently predict the adverse outcomes in the study subjects.

RESULTS

In univariate and stepwise multivariate Cox proportional hazards modeling we found that unit rise in early cTnI is associated with a 3% (95% confidence interval [CI]: 2%- 5%, p < 0.001) faster progression to long-term adverse events after CABG even after adjusting for the type of ACS. Prognostically, the most informative cut off value for cTnI was 5.6 ng/mL. Above this value, CABG patients progressed 2.58 times faster to adverse outcomes (95% CI: 1.05-6.36, p = 0.039). This effect remained after adjustment for other significant confounders namely, poor compliance to medications, female sex, Medicaid insurance, and electrocardiographic ischemia.

CONCLUSION

Early cTnI measurement after admission can predict adverse outcomes after CABG. This association extends to long-term adverse events after CABG.

Cost effectiveness of intensive lipid-lowering treatment for patients with congestive heart failure and coronary heart disease in the US

BACKGROUND

A recent study found fewer hospitalizations for congestive heart failure (CHF) patients receiving high-dose versus low-dose statin therapy.

OBJECTIVE

To examine the cost effectiveness of high-dose versus low-dose statin therapy in CHF patients.

METHODS

Two scenarios (literature-based [base-case scenario] vs trial-based post-event mortality [alternative scenario]) assessed the cost effectiveness of atorvastatin 80 mg/day (A80) versus atorvastatin 10 mg/day (A10) in patients with both CHF and coronary heart disease (CHD) [CHF/CHD], using a lifetime Markov model. The model predicts treatment-specific probabilities of major and minor cardiovascular events and death, based on clinical trial data. The quality of life and costs were literature based. Measures included costs per life-year saved (LYS) and QALY gained. Health consequences and costs were discounted at 3.0% annually. Analyses were conducted from the payer perspective and valued in $US, year 2006-7 values.

RESULTS

Literature-based mortality estimates (base case) increased life-years and QALYs for A80 compared with A10 (incremental cost-effectiveness ratios [ICERs]: $US9600 per LYS; $US13 600 per QALY). At a willingness to pay of $US100 000 per QALY, A80 was cost effective in 80% of simulations. A10 dominated A80 when using trial-based mortality estimates (alternative scenario). At a willingness to pay of $US100 000 per QALY, A80 was cost effective in 48% of simulations.

CONCLUSIONS

Intensive A80 treatment may be cost effective versus A10 in cardiovascular prevention in CHF/CHD patients in the US, due to projected gains in life expectancy and health-related quality of life. However, the results are highly sensitive to assumptions about the mortality rate in the model. When using the mortality rate observed in the trial, A10 dominates A80.

Cost-effectiveness of intensive atorvastatin therapy in secondary cardiovascular prevention in the United Kingdom, Spain, and Germany, based on the Treating to New Targets study

The Treating to New Targets (TNT) clinical trial found that intensive 80 mg atorvastatin (A80) treatment reduced cardiovascular events by 22% when compared to 10 mg atorvastatin (A10) treatment. We evaluated the cost-effectiveness of intensive A80 vs A10 treatment in the United Kingdom (UK), Spain, and Germany. A lifetime Markov model was developed to predict cardiovascular disease-related events, costs, survival, and quality-adjusted life-years (QALYs). Treatment-specific event probabilities were estimated from the TNT clinical trial. Post-event survival, health-related quality of life, and country-specific medical-care costs were estimated using published sources. Intensive treatment with A80 increased both the per-patient QALYs and corresponding costs of care, when compared to the A10 treatment, in all three countries. The incremental cost per QALY gained was <euro> 9,500, <euro> 21,000, and <euro> 15,000 in the UK, Spain, and Germany, respectively. Intensive A80 treatment is estimated to be cost-effective when compared to A10 treatment in secondary cardiovascular prevention.

Cardiac magnetic resonance findings predict increased resource utilization in elective coronary artery bypass grafting

Morbidity following CABG (coronary artery bypass grafting) is difficult to predict and leads to increased healthcare costs. We hypothesized that pre-operative CMR (cardiac magnetic resonance) findings would predict resource utilization in elective CABG. Over a 12-month period, patients requiring elective CABG were invited to undergo CMR 1 day prior to CABG. Gadolinium-enhanced CMR was performed using a trueFISP inversion recovery sequence on a 1.5 tesla scanner (Sonata; Siemens). Clinical data were collected prospectively. Admission costs were quantified based on standardized actual cost/day. Admission cost greater than the median was defined as 'increased'. Of 458 elective CABG cases, 45 (10%) underwent pre-operative CMR. Pre-operative characteristics [mean (S.D.) age, 64 (9) years, mortality (1%) and median (interquartile range) admission duration, 7 (6-8) days] were similar in patients who did or did not undergo CMR. In the patients undergoing CMR, eight (18%) and 11 (24%) patients had reduced LV (left ventricular) systolic function by CMR [LVEF (LV ejection fraction) <55%] and echocardiography respectively. LE (late enhancement) with gadolinium was detected in 17 (38%) patients. The average cost/day was $2723. The median (interquartile range) admission cost was $19059 ($10891-157917). CMR LVEF {OR (odds ratio), 0.93 [95% CI (confidence interval), 0.87-0.99]; P=0.03} and SV (stroke volume) index [OR 1.07 (95% CI, 1.00-1.14); P=0.02] predicted increased admission cost. CMR LVEF (P=0.08) and EuroScore tended to predict actual admission cost (P=0.09), but SV by CMR (P=0.16) and LV function by echocardiography (P=0.95) did not. In conclusion, in this exploratory investigation, pre-operative CMR findings predicted admission duration and increased admission cost in elective CABG surgery. The cost-effectiveness of CMR in risk stratification in elective CABG surgery merits prospective assessment.

High probability of disease in angina pectoris patients: is clinical estimation reliable?

BACKGROUND

According to most current guidelines, stable angina pectoris patients with a high probability of having coronary artery disease can be reliably identified clinically.

OBJECTIVES

To examine the reliability of clinical evaluation with or without an at-rest electrocardiogram (ECG) in patients with a high probability of coronary artery disease.

PATIENTS AND METHODS

A prospective series of 357 patients referred for coronary angiography (CA) for suspected stable angina pectoris were examined by a trained physician who judged their type of pain and Canadian Cardiovascular Society grade of pain. Pretest likelihood of disease was estimated, and all patients underwent myocardial perfusion scintigraphy (MPS) followed by CA an average of 78 days later. For analysis, the investigators focused on the approximate groups of patients with more severe disease, ie, typical angina (n=187), Canadian Cardiovascular Society grade 2 pain or higher (n=176) or high (higher than 85%) estimated pretest likelihood of disease (n=142).

RESULTS

In the three groups, 34% to 39% of male patients and 65% to 69% of female patients had normal MPS, while 37% to 38% and 60% to 71%, respectively, had insignificant findings on CA. Of the patients who had also an abnormal at-rest ECG, 14% to 21% of men and 42% to 57% of women had normal MPS. Sex-related differences were statistically significant.

CONCLUSIONS

Clinical prediction appears to be unreliable. Addition of at-rest ECG data results in some improvement, particularly in male patients, but it makes the high probability groups so small that the addition appears to be of limited clinical relevance.

Changing outcomes of coronary revascularization in British Columbia, 1995-2001

OBJECTIVES

To examine outcomes following all first coronary revascularization procedures, isolated coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) on British Columbia (BC) resident adults from 1995 to 2001.

METHODS

CABG and PCI data were obtained from the BC Cardiac Registry, and mortality data were obtained from the BC Vital Statistics Agency. Analysis was performed by annual cohorts, and the rates reported are unadjusted.

RESULTS

An increasing percentage of revascularization procedures was performed with PCI (62% in 1995 to 73% in 2001; P<0.001) due to the increased use of PCI procedures. Except in emergent cases, 30-day mortality improved after PCI (1.8% to 1.1%; P=0.02) and CABG (1.8% to 1.2%; P=0.01). Emergent cases accounted for 9.0% of PCIs and 2.7% of CABGs, the percentage treated by CABG decreasing from 14.5% in 1995 to 7.5% by 2001 (P<0.001). Mortality rates among emergent cases was higher at 30 days, with no trend in PCI mortality (12%) but a substantial reduction in 30-day mortality after CABG (28% to 10%; P=0.003). One-year survival free from repeat revascularization following PCI increased from 73% in 1995 to 83% in 2001 (P<0.001) and from 94% to 95% (P<0.005) following CABG.

CONCLUSIONS

Improvements in procedure-related mortality observed in trials have extended to clinical practice. With respect to emergent cases, an increasing proportion were treated by PCI with no change in PCI mortality but associated with a drop in surgical mortality. There has been a consistent and substantial drop in the need for repeat procedures within one year for patients selected for PCI.

Using simulation to estimate the cost effectiveness of improving ambulance and thrombolysis response times after myocardial infarction

OBJECTIVES

To quantify the health gains and costs associated with improving ambulance and thrombolysis response times for acute myocardial infarction.

DESIGN

A computer simulation model. PATIENTS/SETTINGS: Patients experiencing acute myocardial infarction in England.

INTERVENTIONS

Improving the ambulance response time to 75% of calls reached within 8 minutes and the hospital arrival to thrombolysis time interval (door-to-needle time) to 75% receiving it within 30 minutes and 20 minutes, compared to best estimates of response times in the mid-1990s.

MAIN OUTCOME MEASURES

Deaths prevented, life years saved, and discounted cost per life year saved.

RESULTS

Improving the ambulance response to 75% of calls within 8 minutes resulted in an estimate of 5 deaths prevented or 57 life years saved per million population per year, with a discounted incremental cost per life year saved of 8540 pounds sterling over 20 years. The corresponding benefit of improving the door-to-needle time to 75% of myocardial infarction patients within 30 minutes was an estimated 2 deaths prevented and 15 life years saved per million population per year, with a discounted incremental cost per life year saved of between 10,150 pounds sterling to 54,230 pounds sterling over 20 years. Little further gain was associated with reaching the 20 minute target. Combining ambulance and thrombolysis targets resulted in 70 life years saved per million population per year.

CONCLUSIONS

Improving ambulance response times appears to be cost effective. Reducing door-to-needle time will have a smaller effect at an uncertain cost. Further benefits may be gained from reducing the time from onset of symptoms to starting thrombolysis.

Potential impact of myocardial perfusion scintigraphy as gatekeeper for invasive examination and treatment in patients with stable angina pectoris: observational study without post-test referral bias

AIMS

To evaluate the impact of using myocardial perfusion scintigraphy (MPS) as gatekeeper for coronary angiography and revascularization in stable angina pectoris.

METHODS AND RESULTS

A prospective series of 507 out of 972 adult patients referred to coronary angiography for known or suspected stable angina pectoris underwent clinical examination followed immediately by MPS, the result of which was not communicated. MPS showed normal perfusion in 258/507 (51%) patients, reversible defects in 201/507 (40%), and fixed defects in 48/507 (9%). Of 168 revascularized patients, 27 (16%) had normal perfusion and 13 (8%) had fixed defects. Coronary angiography was undertaken in 476 patients of whom 252 (53%) had normal findings or insignificant stenoses. The same was the case in 361 (41%) out of the 883 of the 972 consecutive patients, who had this examination. Assuming that the true rate of normal perfusion in the entire series was correspondingly lower, 48% of catheterizations and 19% of revascularizations were superfluous.

CONCLUSION

The use of MPS as gatekeeper appears to make about half of catheterizations and almost one-fifth of revascularizations redundant. Even in high-risk groups, substantial savings are possible, and the risk of overlooking patients with severe disease seems negligible.

Procedure rates and outcomes of coronary revascularization procedures in California and New York

OBJECTIVE

Background data were obtained on all California hospitals performing coronary artery bypass grafting and percutaneous coronary intervention procedures and compared with reports published by the state of New York to develop a collaborative quality improvement program for cardiac surgery programs.

METHODS

The Patient Discharge Database of the Office of Statewide Health Planning and Development was queried for the years 1999-2001. In-hospital mortality and risk factors for coronary artery bypass grafting and percutaneous coronary intervention were obtained by using demographic data and International Classification of Diseases-Ninth Revision-Clinical Modification procedure and diagnosis codes. Risk models were developed by means of logistic regression analysis.

RESULTS

Overall coronary artery bypass grafting mortality was 33% higher and percutaneous coronary intervention mortality was twice as high in California compared with that in New York. Procedural volume (per unit population) was higher in New York. In high-volume California hospitals (>300 procedures per year), coronary artery bypass grafting mortality was similar (California, 2.42%; New York, 2.25%). Excess coronary artery bypass grafting mortality (>4.0%) occurred only in low-volume programs. Risk adjustment did not change the volume effect for coronary artery bypass grafting. No volume effect was noted for risk-adjusted percutaneous coronary intervention mortality. There were no obvious differences in risk factors between California and New York. Programs performing relatively fewer coronary artery bypass grafting procedures compared with percutaneous coronary interventions were found to have significantly higher coronary artery bypass grafting mortality after adjusting for volume effects. Percutaneous coronary intervention volume is increasing and coronary artery bypass grafting volume is decreasing in both California and New York.

CONCLUSIONS

Excess coronary artery bypass grafting mortality in California is related to the large number of low-volume programs. Excess percutaneous coronary intervention mortality might be related to case selection or timing of intervention. A relationship between percutaneous coronary intervention volume and coronary artery bypass grafting mortality is suggested in which increasing percutaneous coronary intervention volume relative to coronary artery bypass grafting volume might have the effect of shifting patients with undefined higher risk characteristics to coronary artery bypass grafting.

Percutaneous transluminal coronary angioplasty with stents versus coronary artery bypass grafting for people with stable angina or acute coronary syndromes

BACKGROUND

Coronary artery bypass graft surgery (CABG) replaces obstructed vessels with ones from other parts of the body. Alternatively, obstructions are remodelled using catheter-based techniques such as percutaneous coronary angioplasty with the use of stents. Though less invasive, stenting techniques are limited by the re-narrowing of treated vessels (restenosis). We examined evidence on cardiac-related outcomes occurring after CABG or stenting, with implications for resource use, resource allocation and informing patient choice.

OBJECTIVES

To examine evidence from randomised controlled trials (RCTs) on benefit of stents or CABG in reducing cardiac events in people with stable angina or acute coronary syndrome (ACS).

SEARCH STRATEGY

CENTRAL (Issue 2 2004), EMBASE (1990 to 2004), MEDLINE (1990 to 2004) and handsearching to July 2004.

SELECTION CRITERIA

Only RCTs comparing stents used with PTCA with CABG were included. Participants were adults with stable angina or ACS and unstable angina and had either single or multiple vessel disease. Published and unpublished sources were considered.

DATA COLLECTION AND ANALYSIS

Outcomes included composite event rate (major adverse cardiac event, event free survival), death, acute myocardial infarction (AMI), repeat revascularisation and binary restenosis as well as information on design and baseline characteristics. Quality assessment was completed independently. Meta-analyses are presented as odds ratios, 95% confidence intervals (CI) using a fixed-effect model. Heterogeneity between trials was assessed.

MAIN RESULTS

Nine studies (3519 patients) were included. Four RCTs included patients with multiple vessel disease, five focused on single vessel disease. Four studies reported beyond 1 year. No statistical differences were observed between CABG and stenting for meta-analysis of mortality or AMI, but there was heterogeneity. Composite cardiac event and revascularisation rates were lower for CABG than for stents. Odds ratios resulting from meta-analysis of event rate data at 1 year were, odds ratio 0.43 (95% CI 0.35 to 0.54) and at 3 years, odds ratio 0.37 (95% CI 0.29 to 0.48). Odds ratios for revascularisation at 1 year were, odds ratio 0.18 (95% CI 0.13 to 0.25) and at 3 years, odds ratio 0.09 (95% CI 0.02 to 0.34). Binary restenosis at 6 months (single vessel trials) favoured CABG, odds ratio 0.29 (95% CI 0.17 to 0.51).

AUTHORS' CONCLUSIONS

CABG is associated with reduced rates of major adverse cardiac events, mostly driven by reduced repeat revascularisation. However, the RCT data are limited by follow-up, unrepresentative samples and rapid development of both surgical techniques and stenting. Research on real-world patient population or patient level data meta-analyses may identify risk factors and groupings who may benefit most from one strategy over the other.

What reimbursement for coronary revascularization with drug-eluting stents?

We investigated the clinical and economic impact of sirolimus-eluting coronary stents (SES) at a nationwide level as to advice about the feasible reimbursement policy for the Italian Health Care System (SSN). A decision model compared bare metal stents (BMS) and SES in terms of costs and repeat coronary revascularizations incurred in 12 months following the first revascularization. The model was compiled for eight subgroups of patients. Rates of events were derived from randomized trials and an 1,809-patient survey. National charges were used to evaluate resources consumption. Compared with BMS, the number of averted revascularizations with SES is 0.16 per patient. SES also save Euro 1,371 per patient. Total savings to SSN are proportional to the rate of SES adoption by Italian hospitals: assuming a complete replacement of BMS with SES, the model estimates that 7,095 revascularizations would be averted and more than Euro 60 million saved by the SSN in 1 year. To stimulate SES adoption a SES-specific DRG might by introduced with a reimbursement value 23% higher than the current charge. SES is thus a cost-saving strategy in the perspective of the SSN that could therefore support the introduction of the new technology by reimbursing about 80% of its current incremental acquisition cost.

Sirolimus-eluting stents for the prevention of restenosis in a worst-case scenario of diffuse and recurrent in-stent restenosis

For recurrent in-stent restenosis (ISR), surgical revascularization or brachytherapy is still the principal therapeutic options. The present investigation explores the efficacy of a sirolimus-eluting stent to prevent restenosis in these lesions with a high risk of recurrence. In 22 consecutive patients with a recurrent and diffuse ISR, a sirolimus-eluting stent was implanted to cover the restenotic lesion. All patients were followed clinically for at least 1 year and underwent a repeat angiography after 7 months. A quantitative coronary angiographic analysis was done. The target vessel failure was 14% in the sirolimus-eluting stent group, with an angiographic late loss of only 0.39 +/- 0.54. No subacute stent thrombosis was observed, and the 1-year event-free survival was 86%. The three cases with restenosis were all focal and could be successfully treated by additional drug-eluting stent implantation. This study showed the efficacy of a sirolimus-eluting stent for the prevention of restenosis in a worst-case scenario of recurrent and diffuse ISR. The observed restenosis rate is lower than that reported after brachytherapy and suggests that sirolimus-eluting stents are a promising treatment option for ISR.

The current cost of angina pectoris to the National Health Service in the UK

OBJECTIVE

To calculate the cost of angina pectoris to the UK National Health Service (NHS) in the year 2000.

METHODS

Calculation of the cost of hospital admissions, revascularisation procedures, hospital outpatient consultations, general practice (GP) consultations, and prescribed drug treatment.

RESULTS

634 000 individuals (1.1% of the UK population) consulted GPs 2.35 million times, costing pound 60.5 million. They required 16.0 million prescriptions (cost pound 80.7 million) and 254 000 hospital outpatient referrals (cost pound 30.4 million). There were 149 000 hospital admissions, 117 000 coronary angiograms, 21 400 coronary artery bypass operations, 17 700 percutaneous coronary interventions, and 516 000 outpatient visits, at a cost of pound 208.4 million, pound 69.9 million, pound 106.2 million, pound 60.7 million, and pound 52.2 million, respectively. The direct cost of angina was therefore pound 669 million (1.3% of total NHS expenditure), with hospital bed occupancy and procedures accounting for 32% and 35% of this total, respectively.

CONCLUSIONS

Angina is a common and costly public health problem. It consumed over 1% of all NHS expenditure in the year 2000, mainly because of hospital bed occupancy and revascularisation procedures. This is likely to be a conservative estimate of its true cost.

Missing, mediocre, or merely obsolete? An evaluation of UK data sources for coronary heart disease

STUDY OBJECTIVE

Coronary heart disease (CHD) is the commonest cause of death in the UK. However, there is no single comprehensive source of information to support CHD prevention and treatment strategies. Therefore this study evaluated the availability and quality of UK CHD data sources since 1981.

DESIGN

Data sources for England and Wales were identified and appraised on: (1) CHD patient numbers (myocardial infarction, angina, hypertension, and heart failure); (2) uptake of medical and surgical CHD treatments, and (3) population trends in major cardiovascular risk factors.

SETTING

England and Wales (population 53 million).

MAIN RESULTS

Population and mortality data were easily accessible from Office for National Statistics and British Heart Foundation Annual CHD Statistics; population based risk factor data came principally from the British Regional Heart Study, the General Household Survey, and the Health Survey for England. They were limited for 1981, but more extensive by 2000. Hospital admissions information since 1998 was available online from HES; but trend data and details of interventions were scant. Limited primary care data on consultation rates, prescribing, and treatment uptake were available from published audits and studies.

CONCLUSIONS

Information on CHD in the UK is fragmented, patchy, and mixed in quality. Data for women, the elderly populatiom, and ethnic minorities were particularly scarce, exacerbating inequalities. Future CHD disease monitoring and evaluation will require comprehensive and accurate population based information on trends in patient numbers, treatment uptake, and risk factors.