Practolol in Treatment of Angina Pectoris. A Double-blind Trial

Twenty-four patients with angina pectoris entered a double-blind trial of the cardioselective beta-adrenergic blocking agent practolol. Seventeen experienced less angina and consumed fewer glyceryl trinitrate tablets when on the active preparation. There was also a decrease in the mean number of attacks suffered by patients while on practolol and a reduction in the number of glyceryl trinitrate tablets taken. These results are of statistical significance at, at least, the 5% level.     

Hospital admissions for asthma in east London: associations with characteristics of local general practices,prescribing, and population.

OBJECTIVE: To determine the relative importance of appropriate prescribing for asthma in explaining high rates of hospital admission for asthma among east London general practices. DESIGN: Poisson regression analysis describing relation of each general practice''s admission rates for asthma with prescribing for asthma and characteristics of general practitioners, practices, and practice populations. SETTING: East London, a deprived inner city area with high admission rates for asthma. SUBJECTS: All 163 general practices in East London and the City Health Authority (complete data available for 124 practices). MAIN OUTCOME MEASURES: Admission rates for asthma, excluding readmissions, for ages 5-64 years; ratio of asthma prophylaxis to bronchodilator prescribing; selected characteristics of general practitioners, practices, and practice populations. RESULTS: Median admission rate for asthma was 0.9 (range 0-3.6) per 1000 patients per year. Higher admission rates were most strongly associated with small size of practice partnership: admission rates of singlehanded and two partner practices were higher than those of practices with three or more principals by 1.7 times (95% confidence interval 1.4 to 2.0, P < 0.001) and 1.3 times (1.1 to 1.6, P = 0.001) respectively. Practices with higher rates of night visits also had significantly higher admission rates: an increase in night visiting rate by 10 visits per 1000 patients over two years was associated with an increase in admission rates for asthma by 4% (1% to 7%). These associations were independent of asthma prescribing ratios, measures of practice resources, and characteristics of practice populations. CONCLUSIONS: Higher asthma admission rates in east London practices were most strongly associated with smaller partnership size and higher rates of night visiting. Evaluating ways of helping smaller partnerships develop structured proactive care for asthma patients at high risk of admission is a priority.     

Catchment areas in general practice and their relation to size and quality of practice and deprivation: a descriptive study in one London borough.

OBJECTIVE: To relate the sizes of general practice catchment areas in one London borough to list size, deprivation payments, medical staffing, and locally and nationally recognised measures of quality. DESIGN: Study of general practice catchment area maps. SETTING: London borough of Lambeth. SUBJECTS: 60 out of the 71 general practices in Lambeth. MAIN OUTCOME MEASURES: Practice catchment area size with corrections for numbers of doctors and patients. RESULTS: Catchment area size varied greatly between practices, showing an almost 150-fold difference between the largest and smallest practices. This size differential was even more marked when the size of the catchment area was corrected for the number of general practitioners in the practice, where a 300-fold difference was found. Substantial differences existed between practices in each of the four locally assigned quality bands. The weakest practices had catchment areas three times as large as those of the strongest practices. When corrected for medical staffing, the difference was eight times as great. A calculated measure of patient dispersion showed that the practice population of the strongest practices was four times as densely clustered as that of the weakest practices, whose patients were more widely geographically dispersed. CONCLUSIONS: Large variations exist in the size of catchment areas of inner city practices even when corrected for numbers of doctors and patients. These differences are associated with variations in quality of care.     

A comparative study of glyceryl trinitrate biotransformation and glyceryl trinitrate induced relaxation in bovine pulmonary artery and vein

Recent evidence supports the hypothesis that the mechanism by which glyceryl trinitrate induces relaxation of vascular smooth muscle involves the biotransformation of glyceryl trinitrate. This study was conducted to determine if there was a direct correlation between the capacity of vascular smooth muscle preparations to biotransform glyceryl trinitrate and their sensitivity to the relaxant effect of this organic nitrate. Isolated bovine pulmonary arteries and veins were contracted submaximally and cumulative dose-response relationships to glyceryl trinitrate were obtained; the vein was approximately 10 times more sensitive than the artery to glyceryl trinitrate induced relaxation. In a separate series of experiments, these vascular tissues were contracted submaximally and incubated with 0.5 microM [14C]glyceryl trinitrate for 2 min, during which glyceryl trinitrate induced relaxation was monitored. At 2 min, tissue samples were taken for determination of glyceryl trinitrate and glyceryl-1,2- and 1,3-dinitrate content by thin-layer chromatography and liquid scintillation spectrometry. Biotransformation of glyceryl trinitrate to glyceryl dinitrate occurred concomitantly with relaxation of these blood vessels. The concentration of glyceryl dinitrate in the vein was significantly less than that in the artery (p less than or equal to 0.05), even though significantly greater relaxation of the vein than the artery was observed (p less than or equal to 0.05). From these data, a simple linear relationship between glyceryl trinitrate biotransformation and relaxation is not apparent.     

Understanding the expanding role of primary care physicians (PCPs) to primary psychiatric care physicians (PPCPs): enhancing the assessment and treatment of psychiatric conditions

Aim In the current healthcare system primary care physicians (PCPs) have, in effect, become the primary psychiatric care physicians (PPCPs) for many of their patients. Being the PPCP in an already busy and stressful medical industry presents additional time management and treatment challenges to successfully manage patients' medical and psychiatric needs. The aim of the study was to ascertain PCPs' psychiatric assessment and treatment practices and to determine the extent to which PCPs have a need for using a structured psychiatric assessment tool.Method We sent 300 PCPs a survey to examine their psychiatric assessment and treatment practices. A one-page questionnaire was used to inquire about PCPs' psychiatric care practice habits including types of conditions treated, psychiatric medications prescribed, assessment methods used, interest in using a structured assessment tool and referral sources used. Sixty-eight usable surveys (23%) were returned.Results PCPs identify approximately one-third of their patients as mental health patients. They are treating a wide range of psychiatric conditions and prescribing a variety of psychiatric medications. The vast majority are using traditional clinical interviewing as their primary method of psychiatric assessment. However, the majority were willing to use a structured psychiatric assessment tool.Conclusion PCPs are serving a useful role in providing psychiatric treatment to many of their patients. Using a more structured psychiatric assessment method in practice could ultimately strengthen the assessment and treatment of psychiatric conditions in primary care settings.     

A Cluster Randomised Controlled Trial of a Pharmacist-Led Collaborative Intervention to Improve Statin Prescribing and Attainment of Cholesterol Targets in Primary Care

Background

Small trials with short term follow up suggest pharmacists’ interventions targeted at healthcare professionals can improve prescribing. In comparison with clinical guidance, contemporary statin prescribing is sub-optimal and achievement of cholesterol targets falls short of accepted standards, for patients with atherosclerotic vascular disease who are at highest absolute risk and who stand to obtain greatest benefit. We hypothesised that a pharmacist-led complex intervention delivered to doctors and nurses in primary care, would improve statin prescribing and achievement of cholesterol targets for incident and prevalent patients with vascular disease, beyond one year.

Methods

We allocated general practices to a 12-month Statin Outreach Support (SOS) intervention or usual care. SOS was delivered by one of 11 pharmacists who had received additional training. SOS comprised academic detailing and practical support to identify patients with vascular disease who were not prescribed a statin at optimal dose or did not have cholesterol at target, followed by individualised recommendations for changes to management. The primary outcome was the proportion of patients achieving cholesterol targets. Secondary outcomes were: the proportion of patients prescribed simvastatin 40 mg with target cholesterol achieved; cholesterol levels; prescribing of simvastatin 40 mg; prescribing of any statin and the proportion of patients with cholesterol tested. Outcomes were assessed after an average of 1.7 years (range 1.4–2.2 years), and practice level simvastatin 40 mg prescribing was assessed after 10 years.

Findings

We randomised 31 practices (72 General Practitioners (GPs), 40 nurses). Prior to randomisation a subset of eligible patients were identified to characterise practices; 40% had cholesterol levels below the target threshold. Improvements in data collection procedures allowed identification of all eligible patients (n = 7586) at follow up. Patients in practices allocated to SOS were significantly more likely to have cholesterol at target (69.5% vs 63.5%; OR 1.11, CI 1.00–1.23; p = 0.043) as a result of improved simvastatin prescribing. Subgroup analysis showed the primary outcome was achieved by prevalent but not incident patients. Statistically significant improvements occurred in all secondary outcomes for prevalent patients and all but one secondary outcome (the proportion of patients with cholesterol tested) for incident patients. SOS practices prescribed more simvastatin 40 mg than usual care practices, up to 10 years later.

Interpretation

Through a combination of educational and organisational support, a general practice based pharmacist led collaborative intervention can improve statin prescribing and achievement of cholesterol targets in a high-risk primary care based population.

Trial Registration

International Standard Randomised Controlled Trials Register ISRCTN61233866     

Assessment of dermal glyceryl trinitrate and isosorbide dinitrate for patients with angina pectoris.

Dermal nitrate preparations are claimed to be useful in the treatment of angina, as their slow absorption by-passing the liver leads to a sustained action. Ten patients with angina were exercised on a treadmill after dermal application of 16.64 mg glyceryl trinitrate or 100 mg isosorbide dinitrate or placebo. Exercise duration was significantly increased at one and three hours for both nitrate preparations but not at six hours after application. The calculated workload achieved was significantly increased (p less than 0.01) at one and three hours for both preparations and at six hours (p less than 0.05) for isosorbide dinitrate. Headaches were common with glyceryl trinitrate cream. The dermal nitrate preparations studied had a duration of antianginal action similar to that of oral nitrate tablets. Aside from their value when the oral route cannot be used or absorption may be delayed, dermal nitrate preparations have no advantage over oral preparations for angina pectoris.     

Computerisation of primary care in Wales.

OBJECTIVE--To obtain information about the computerisation of general practice in Wales, and to enable more effective planning of educational provision for doctors and other primary health care workers. DESIGN--Postal questionnaire sent to all general practices in Wales. SUBJECTS--553 general practices, of which 401 (73% replied). RESULTS--The level of computerisation varied from 11 (85%) of practices in Powys Family Health Services Authority to 22 (40%) in Mid Glamorgan. Less than half of practices had a computer in only two authorities. The commonest uses of the computer were for patient registration (208 practices), repeat prescribing (180), call and recall of patients (165), and partial clinical records (122). The main suppliers were VAMP (78 practices), AAH Meditel (46), and AMC (23). 102 of 226 practices with a computer had a terminal on each doctor''s desk. Just 33 practices had full patient notes on computer and 51 had modems for electronic communication. CONCLUSION--Mechanisms to encourage greater and more sophisticated use of computers and information technology need to be explored.     

Transferring the costs of expensive treatments from secondary to primary care.

General practitioners, especially fundholders, are becoming increasingly concerned about being asked to prescribe treatments for their patients that are outside their therapeutic experience. They are concerned about the clinical responsibility for such prescribing and the effects on their budgets. In some specialties transferring the costs of expensive treatments from secondary to primary care (cost shifting) has become partly institutionalised because of the separate sources of funding for drugs prescribed in the two sectors. With increased efforts to control the rising costs of the drugs budget and the emergence of new expensive treatments, cost shifting will be a challenge to clinicians and purchasers as they strive for rational, cost effective prescribing. A review of the funding mechanisms for drugs prescribing and of the relation between the licensing process and the decision to support the use of a treatment in primary or secondary care is needed.     

Pragmatic randomised controlled trial to evaluate guidelines for the management of infertility across the primary care-secondary care interface

ObjectiveTo investigate the effect of clinical guidelines on the management of infertility across the primary care-secondary care interface.DesignCluster randomised controlled trial.SettingGeneral practices and NHS hospitals accepting referrals for infertility in the Greater Glasgow Health Board area.ParticipantsAll 221 general practices in Glasgow; 214 completed the trial.InterventionGeneral practices in the intervention arm received clinical guidelines developed locally. Control practices received them one year later. Dissemination of the guidelines included educational meetings.ResultsData on 689 referrals were collected. No significant difference was found in referral rates for infertility. Fewer than 1% of couples were referred inappropriately early. Referrals from intervention practices were significantly more likely to have all relevant investigations carried out (odds ratio 1.32, 95% confidence interval 1.00 to 1.75, P=0.025). 70% of measurements of serum progesterone concentrations during the midluteal phase and 34% of semen analyses were repeated at least once in hospital, despite having been recorded as normal when checked in general practice. No difference was found in the proportion of referrals in which a management plan was reached within one year or in the mean duration between first appointment and date of management plan. NHS costs were not significantly affected.ConclusionsDissemination of infertility guidelines by commonly used methods results in a modest increase in referrals having recommended investigations completed in general practice, but there are no detectable differences in outcome for patients or reduction in costs. Clinicians in secondary care tended to fail to respond to changes in referral practice by doctors. Guidelines that aim to improve the referral process need to be disseminated and implemented so as to lead to changes in both primary care and secondary care.

What is already known on this topic

Most previous research into clinical guidelines has focused on their development and implementationEvidence is lacking about the outcomes and costs associated with the use of clinical guidelines

What this study adds

Clinical guidelines that may alter the balance of care between general practice and hospital settings require more intensive implementation than guidelines aimed at either setting on its ownThe cost effectiveness of clinical guidelines should not be assumed     

Need and demand for primary health care: a comparative survey approach.

OBJECTIVE--To develop general practice profiles of needs and demand for primary health care. DESIGN--Postal survey of a stratified random sample of 3478 people registered with five general practices. Data from a single practice were compared with data from the remaining four to identify areas of comparative need. SETTING--Five general practices in Lothian. MAIN OUTCOME MEASURES--Differences between the single practice and the comparison practices in terms of social and economic circumstances, limiting long term illness, specific ongoing conditions, minor illness or symptoms, psychosocial problems, discussion of lifestyle, associated use of services. RESULTS--Respondents from the single practice reported higher rates than those in the four comparison practices of ongoing mental health and respiratory problems and use of antidepressants, tranquillisers, or sleeping tablets. Although rates of limiting long term illness and other specific ongoing conditions were comparable, the rates of minor illness or symptoms and psychosocial difficulties were higher in the single practice. Respondents from the single practice were more likely to consult frequently, to have contacted the practice out of normal working hours, and to have discussed psychosocial difficulties with a general practitioner. For any specific ongoing condition or "minor" illness, respondents from the single practice were no more likely to consult. CONCLUSIONS--A comparative survey approach is a useful method of developing an understanding of patterns of need and demand among general practice populations. It has the potential to inform planning within individual general practices and the process of commissioning among general practices within a given area.     

Interaction between cigarettes and propranolol in treatment of angina pectoris.

To determine whether cigarette smoking interferes with the medical management of angina pectoris, 10 patients with angina pectoris who smoked at least 10 cigarettes a day were studied before, during, and after a standardised maximal exercise test. This was done at the end of four randomly allocated one-week treatment periods during which the patients took glyceryl trinitrate while not smoking, took glyceryl trinitrate while smoking, took glycerly trinitrate and propranolol (380 mg/day) while not smoking, and took glyceryl trinitrate and propranolol while smoking. Carboxyhaemoglobin was measured to ensure compliance. Smoking was associated with a significantly higher heart rate, blood pressure, number of positions with ST-segment depression, and total ST-segment depression after exercise than non-smoking (p < 0.01) whether or not the patients were taking propranolol. These results suggest that smoking aggravates the simple haemodynamic variables used to assess myocardial oxygen requirements and the exercise-induced precordial electrocardiographic signs of myocardial ischaemia. These effects were still evident after treatment with propranolol and represent a hindrance to the effective medical treatment of angina pectoris.     

Cytochrome P-450 mediated biotransformation of organic nitrates

The vascular biotransformation of organic nitrates appears to be a prerequisite for their action as vasodilators. In the current study, we assessed the involvement of cytochrome P-450 in the denitration of glyceryl trinitrate and the enantiomers of isoidide dinitrate. Denitration of organic nitrates by the microsomal fraction of rat liver was NADPH dependent and followed apparent first-order kinetics. Under aerobic conditions, the t1/2 of D-isoidide dinitrate was significantly shorter than that of L-isoidide dinitrate (11.9 vs. 14.1 min, p less than or equal to 0.05), which is consistent with the greater potency of the D-enantiomer for vasodilation. Under anaerobic conditions, the denitration of glyceryl trinitrate was very rapid (t1/2 approximately 30 s). Organic nitrate biotransformation was inhibited by carbon monoxide, SKF 525A, and dioxygen. This suggests that the biotransformation of organic nitrates can occur through the direct interaction with the heme moiety of cytochrome P-450. The biotransformation of glyceryl trinitrate was catalyzed preferentially by those isoenzymes induced by phenobarbital. The biotransformation of glyceryl trinitrate was regioselective for 1,3-glyceryl dinitrate formation except in phenobarbital-induced microsomes under aerobic conditions, in which preferential formation of 1,2-glyceryl dinitrate occurred. These data suggest that cytochrome P-450 is involved in the biotransformation of organic nitrates and raises the possibility that vascular cytochrome P-450 may play a role in the mechanism-based biotransformation of organic nitrates, the result of which is vascular smooth muscle relaxation.     

Computerized clinical decision support systems for acute care management: A decision-maker-researcher partnership systematic review of effects on process of care and patient outcomes

Background

There is a need to find innovative approaches for translating best practices for chronic disease care into daily primary care practice routines. Primary care plays a crucial role in the prevention and management of cardiovascular disease. There is, however, a substantive care gap, and many challenges exist in implementing evidence-based care. The Improved Delivery of Cardiovascular Care (IDOCC) project is a pragmatic trial designed to improve the delivery of evidence-based care for the prevention and management of cardiovascular disease in primary care practices using practice outreach facilitation.

Methods

The IDOCC project is a stepped-wedge cluster randomized control trial in which Practice Outreach Facilitators work with primary care practices to improve cardiovascular disease prevention and management for patients at highest risk. Primary care practices in a large health region in Eastern Ontario, Canada, were eligible to participate. The intervention consists of regular monthly meetings with the Practice Outreach Facilitator over a one- to two-year period. Starting with audit and feedback, consensus building, and goal setting, the practices are supported in changing practice behavior by incorporating chronic care model elements. These elements include (a) evidence-based decision support for providers, (b) delivery system redesign for practices, (c) enhanced self-management support tools provided to practices to help them engage patients, and (d) increased community resource linkages for practices to enhance referral of patients. The primary outcome is a composite score measured at the level of the patient to represent each practice's adherence to evidence-based guidelines for cardiovascular care. Qualitative analysis of the Practice Outreach Facilitators' written narratives of their ongoing practice interactions will be done. These textual analyses will add further insight into understanding critical factors impacting project implementation.

Discussion

This pragmatic, stepped-wedge randomized controlled trial with both quantitative and process evaluations demonstrates innovative methods of implementing large-scale quality improvement and evidence-based approaches to care delivery. This is the first Canadian study to examine the impact of a large-scale multifaceted cardiovascular quality-improvement program in primary care. It is anticipated that through the evaluation of IDOCC, we will demonstrate an effective, practical, and sustainable means of improving the cardiovascular health of patients across Canada.

Trial Registration

ClinicalTrials.gov: NCT00574808     

Characteristics of primary health care units with focus on drug information from the pharmaceutical industry and adherence to prescribing objectives: a cross-sectional study

Background  

Adherence to prescribing guidelines varies between primary health care units. The aim of the present study was to investigate correlations between characteristics of primary health care units and adherence to prescribing objectives for rational drug use with focus on drug information from the pharmaceutical industry.     

Characteristics of primary care practices associated with high quality of care

Background:

No primary practice care model has been shown to be superior in achieving high-quality primary care. We aimed to identify the organizational characteristics of primary care practices that provide high-quality primary care.

Methods:

We performed a cross-sectional observational study involving a stratified random sample of 37 primary care practices from 3 regions of Quebec. We recruited 1457 patients who had 1 of 2 chronic care conditions or 1 of 6 episodic care conditions. The main outcome was the overall technical quality score. We measured organizational characteristics by use of a validated questionnaire and the Team Climate Inventory. Statistical analyses were based on multilevel regression modelling.

Results:

The following characteristics were strongly associated with overall technical quality of care score: physician remuneration method (27.0; 95% confidence interval [CI] 19.0–35.0), extent of sharing of administrative resources (7.6; 95% CI 0.8–14.4), presence of allied health professionals (15.3; 95% CI 5.4–25.2) and/or specialist physicians (19.6; 95% CI 8.3–30.9), the presence of mechanisms for maintaining or evaluating competence (7.7; 95% CI 3.0–12.4) and average organizational access to the practice (4.9; 95% CI 2.6–7.2). The number of physicians (1.2; 95% CI 0.6–1.8) and the average Team Climate Inventory score (1.3; 95% CI 0.1–2.5) were modestly associated with high-quality care.

Interpretation:

We identified a common set of organizational characteristics associated with high-quality primary care. Many of these characteristics are amenable to change through practice-level organizational changes.A health care system is only as strong as its primary care sector,¹ which provides “entry into the system for all new needs and problems, provides person-focused (not disease-oriented) care over time, provides care for all but very uncommon or unusual conditions …”² Patient enrolment, team-based care, information technology, and funding and remuneration schemes that foster comprehensiveness and collaboration are key characteristics of effective primary care systems.³ None can be singled out as the most determining, but how they are clustered defines a limited set of organizational models that have been associated with a variety of outcomes.⁴ Canadian provinces have implemented different primary care models with different scopes of changes.⁵ Research has not yet identified a “winning” model. For example, in Ontario, community health centres deliver better chronic illness care⁶ but have less accessibility than fee-for-service enrolment models,⁷ and no model provided more comprehensive preventive care.⁸ Walk-in clinics achieved better quality scores than did family medicine clinics for treatment of a set of acute problems.⁹ How the work is organized may be as important, if not more important, than what the model is called.These observations suggest that the challenges associated with providing high-quality services differ depending on the nature of care considered.^9–11 Even if chronic illness is a major challenge, the quality of care must not be improved at the expense of accessibility, preventive or good episodic care, which are all essential components of primary care.In this study, we report the results of the quantitative component of a multimethod observational study conducted in Quebec to determine which organizational characteristics of primary care practices are associated with high-quality care. We sought to find a quality measure of care that would encompass the comprehensive nature of primary care (episodic, chronic and preventive care), and we explored how the contribution of organizational characteristics varied based on the type of care provided.