The effectiveness of general practice nurse interventions in cardiac risk factor reduction among adults: A systematic review

Protocol CENTRE CONDUCTING THE REVIEW Name: New South Wales Centre for Evidence Based Health Care Contact for Review: Dr Elizabeth Halcomb Phone: (02) 9828 6538 Fax: (02) 9828 6519 Email:[email protected] Primary reviewer Name Dr Elizabeth Halcomb Phone: (02) 9828 6538 Fax: (02) 9828 6519 Email:[email protected] Secondary reviewers Name: Prof. Rhonda Griffiths Phone: (02) 98286537 Fax: (02) 98286519 Email: [email protected] Name Ms Suzane Moujalli Phone: (02) 98286538 Fax: (02) 98286519 Email:[email protected] Name: A/Prof. Patricia Davidson Phone: (02) 8838 2051 Fax: (02) 98403629 Email: [email protected] Commencement date January 2006 Expected completion date October 2006 INTRODUCTION Background In recent years there has been a shift in health service delivery from institutional to communitybased care for many acute and chronic conditions(1–8). There is an increase in early hospital discharges and there have been moves to enhance shared care between acute care providers and general practitioners(9–12). Thus, there is an increasing prevalence of chronic illness within the community that requires ongoing, and increasingly complex, management(2, 6, 13–17). Given that contemporary models of care are, increasingly, unable to meet the needs of those with major chronic illness(17, 18), alternate models need to be explored in terms of both their cost to the health system and added value to consumers(5, 19). The ageing population, improved survival from acute cardiac events and increasing incidence of lifestyle risk factors all impact upon CVD incidence within the community(14, 20). Interventions such as lifestyle and risk factor modification aimed at those at the ‘well’ end of the illness trajectory can potentially improve health outcomes by slowing the development of symptomatic disease. It is this premise that highlights the important and emerging role of general practice in both risk factor reduction and CVD management. With its’ comparatively high incidence of acute events and service utilisation pattern, CVD is an excellent exemplar for other chronic diseases(21). Therefore, establishing the efficacy of intervention in this group will demonstrate potential transferability to other disease groups. General practice, defined as health care provided by general practitioners and general practice nurses in the community setting, is seen to offer greater flexibility, higher levels of efficiency and more client focused health care delivery than is possible in the acute care sector(11). The potential for general practice to make an important contribution to the changing health care system becomes clear given that 85% of Australians attend their general practice each year(9, 22–24). This high rate of service utilisation places general practice in a prime position to implement comprehensive screening, disease prevention and chronic disease management programs(8, 20, 25, 26). Although nurses have been employed in general practice for many years, they are a relatively invisible nursing specialty in many countries, such as Australia. However, in countries such as the United Kingdom and New Zealand, practice nursing is highly developed and an integral component of the delivery of primary care(27–29). The practice nurse is either a registered or enrolled nurse who provides general nursing management within the setting of general practice under some degree of supervision from their employing general practitioner(s)(30, 31). This is intended to be, at least partially, a collaborative model in which the practice nurse and general practitioner work in complementary roles to increase available services and improve the quality of care delivered in general practice(31–33). Whilst some specialty models of care have been reported in the literature, most practice nurses work as general nurses(34). Significant research has described the role of practice nurses and their demographic characteristics(7, 27, 35–44), as well as establishing the acceptability of the general practice nurse role to consumers(45–50). What is less clear is the effectiveness of practice nurse interventions aimed at managing chronic disease and reducing lifestyle risk factors. Given the similarities in title, it is important to differentiate the practice nurse from the nurse practitioner. A nurse practitioner is a specialist and autonomous advanced practice clinician providing health care within a defined specialty field which may or may not be within the general practice or primary care setting(51). The nurse practitioner incorporates aspects of diagnosis and treatment within their role. In this model of care, the nurse practitioner substitutes for the doctor in a range of pre-defined, protocol driven, clinical tasks. Although the efficacy of the nurse practitioner role in general practice has been evaluated with mixed success in various randomised control trials(52–55), it represents a separate issue to that of practice nurse role development. Significant research provides evidence for the efficacy of the role of the nurse in the multidisciplinary management of CVD in the acute and outpatient settings(56–63). The allure of the potential role for the practice nurse is that they are located within the familiar environment of the general practice setting and, as such, are familiar to the patient and available for prolonged engagement(29). Additionally, interventions are able to be undertaken at a time when the patient is ready to initiate change rather than at a time of acute crisis as is the case during hospital admission(29, 64). Whilst studies involving practice nurse intervention in CVD have been included in a previous systematic review, this review pooled results from investigations of interventions undertaken by general practice nurses with those undertaken by specialist cardiac nurses(65). These analyses preclude evaluation of the effectiveness of interventions delivered by the practice nurse. Additionally, the pooling of studies with such heterogeneous interventions has implications for misinterpretation of the pooled findings. This review was initiated to synthesise the best evidence regarding the effectiveness of practice nurse interventions in cardiovascular disease management or reduction of cardiac risk factors, with a view to providing an evidence-base on which to develop future research. Objectives The specific questions that this review seeks to address are: a) What is the effectiveness of interventions to reduce cardiovascular risk factors delivered by the general practice nurse in adult patients with CVD, patients with known cardiac risk factors and the general population? b) What is the effect of multifaceted compared to targeted interventions for the reduction of cardiovascular risk factors in adult patients with CVD, patients with known cardiac risk factors and the general population? REVIEW METHOD Inclusion Criteria Types of Studies This review will focus upon all randomised trials that investigate the effectiveness of interventions for CVD management or risk factor reduction undertaken by the general practice nurse. The search will be limited to English language publications given the resource limitations that prohibit translation of papers from other languages. Should there be insufficient randomised trials identified, consideration will be given to including studies using comparative designs. Types of Participants This review will consider all studies that report relevant interventions involving individuals aged 18 years and older. Types of Interventions Trials will be considered for inclusion in the review if they report any kind of intervention delivered by the practice nurse related to CVD management or cardiovascular risk factor reduction. The interventions of interest are related to: health assessment; lifestyle modification; counselling; referral; and, support. Types of Outcomes The primary outcomes of interest are either objective or subjective measures of cardiac risk factors. These measures include: adverse events (e.g. hospital admission, death, myocardial infarction), smoking cessation, body weight, blood pressure, cholesterol level, physical activity, dietary intake, and alcohol consumption. The secondary outcomes of interest are the cost-effectiveness of the intervention and clinician / consumer satisfaction. Exclusion Criteria This review will exclude studies in which the general practice nurse did not deliver the intervention or those that reported interventions delivered by a combination of specialist and practice nurses. However, studies will be included where one arm of the study reports an intervention delivered by the general practice nurse and the data for this arm could be separated from other results. Search Strategy The literature search will seek to systematically identify both published and unpublished trials in the English language. Search strategies will be developed in conjunction with the Library manager after preliminary searches to identify optimal keywords. Given the variations in terminology and syntax between the different electronic databases, individual search strategies will be developed for each electronic database. These search strategies will be used to search: Medline (1966-November Week 3 2005), CINAHL (1982-November Week 3 2005) and the Cochrane Controlled Trials Register (Issue 4, 2005 Cochrane Library). In addition, the reference lists of retrieved papers and relevant reports, conference proceedings, unpublished literature (e.g. theses) and the Internet, using the Google search engine, will be scrutinised for further primary research. Electronic searching of the full text versions of the British Medical Journal (1994-), Family Practice (1997-), Journal of Clinical Nursing (1997-), and Journal of Advanced Nursing (1993-) will be undertaken as these journals are electronically available in full text and have been identified as commonly publishing relevant papers. Bibliographic details and abstracts of the papers identified through the above search strategy will be either exported directly from the electronic database or directly entered into a bibliographic software package (EndnoteTM 7.0). After duplicate results are removed, the titles, abstracts and key words / MeSH terms will be assessed against the inclusion and exclusion criteria independently by two reviewers. Where the paper appeared to meet the inclusion criteria or the abstract was inconclusive, the full text of the publication will be obtained for comprehensive analysis against the inclusion criteria. Any disparities in decision-making will be settled by a third reviewer. Critical Appraisal Where data is identified to be missing or clarification was required attempts will be made to contact the authors for further information. If the same trial is reported in more than one publication, these publications will be considered collectively within the review as a single trial. The methodological quality of all included trials will be assessed using a quality assessment tool modified from the Jadad Scale that has been developed and piloted by the review team. This scale evaluates study quality based upon the description of the study, methods of randomisation and description of final study cohort. Measure of agreement between the two independent assessors will be calculated using the kappa statistic(66). Data Extraction Data from included trials will be extracted and summarised by two reviewers into summary tables modified from those of the Cochrane Collaboration and the Centre for Reviews and Dissemination. The format of these tables will be piloted by the reviewers prior to the commencement of data extraction. All summary tables will be reviewed and cross-checked by a third reviewer. Discrepancies between any of the reviewers will be resolved through discussions between the three reviewers. Reviewers will not be blinded to the bibliographic details of the papers, such as the authors’ names and affiliations. Data Synthesis All calculations will be made using the Cochrane statistical package Review Manager (RevMan) Version 4.1. Clinical heterogeneity will be assessed by considering the populations, interventions and outcomes between the studies. Statistical heterogeneity will be investigated by calculating the I2 statistic, and if this indicates a high level of heterogeneity among the trials included in an analysis, a random effects meta-analysis will be preferred for an overall summary. Where high levels of heterogeneity are found they will be explored by the pre-specified sub-group analyses and by sensitivity analyses excluding the trials most susceptible to bias based on the quality assessment: those with inadequate allocation concealment (B or C); high levels of post randomisation losses or exclusions (D); or unblinded outcome assessment, or uncertain blinding of outcome assessment. Fixed effects meta-analysis will be used for combining study data if the trials are judged to be sufficiently similar. Relative risks and 95% confidence intervals (CI) will be calculated for dichotomous data. Analysis of continuous data will be undertaken using the mean and standard deviation values to derive weighted mean differences (WMD) and their 95% CIs. Where synthesis is inappropriate a narrative overview will be undertaken. For cluster randomised controlled trials, if the analysis accounted for the cluster design then a direct estimate of the desired treatment effect will be extracted e.g. RR plus 95% CI. If cluster specific analysis was not undertaken data relating to the number of clusters randomized to each intervention, the average cluster size in each intervention group and the outcome data (e.g. number or proportion of individuals with events, or means and standard deviations), ignoring the cluster design, for all individuals in each intervention group will be extracted. Next using an external estimate of the intracluster coefficient (ICC) a design effect will be estimated. Hence, we will inflate the variance of the effect estimate. It will then be possible to enter the data into RevMan and combine the cluster randomised trials with individually randomised trials in the same meta-analysis, using generic inverse variance methods of meta-analysis. Given the heterogeneity of the population sub-groups to be analysed in this review, subgroup analysis will be undertaken to assess the impact of interventions in those with known CVD, identified cardiac risk factors or the general community.