In this paper we describe the design of a randomized controlled trial of a case management program led by a trained PN, the case manager, for comorbid T2DM patients. The project will represent a first step in the evidence about the effectiveness of a primary care based case management program by studying the effectiveness in the Dutch primary care setting of a program which has been proven feasible and acceptable in the USA. By superposing this case management program on a diabetes management program, we will also be able to identify its additional value compared to a single disease oriented management program.
We expect that better structured care based on scientific evidence and adjusted to the patients' needs and priorities can improve the quality of care coordination from both the patients' and caregivers' perspective and can result in less consumption of health care services. Patients with more than one chronic condition might need support to coordinate their care arrangements. This is reflected by the choice for quality of care as perceived by the patient as the main outcome measure. When case management superposed on diabetes management is more effective than diabetes management alone, many patients will benefit from a better organized care, better health outcomes, and more efficient use of health care services. From a societal perspective, effective case management will lead to more efficient health care utilization, and consequently lower costs.
The major strength of this study is the close fit to the normal procedure in primary care practice and the not invasive character of the case management program. Experiments with case management as proposed in this study are a logical next step in pursuing optimal care for diabetics with comorbidity, with the knowledge that more than 60% of the diabetics have one or more comorbid disorders. Also, when people get older, the prevalence of chronic illnesses increases. Taking this into account, care for comorbid diabetics can become very complex to manage. The model of case management superposed on disease management for diabetics can be seen as exemplary and it will be worthwhile to apply the results - if positive - to other single-disease management programs for other chronic diseases.
The designed program is based on the Guided Care Model which is under study in the USA. There are three major differences between the implementation of the case management program in the USA and the customized version in our study.
At first, we do not screen for eligible patients based on their health care consumption (or costs) or based on frailty measures. We have chosen to include a group of patients already enrolled in a diabetes management program, who are diagnosed with multiple chronic conditions. Because they have multiple chronic conditions, they could participate in several disease management programs. These programs aim at structuring and managing all care necessary according to the evidence-based guidelines for the specific chronic disease. However, these programs are not designed to complement each other and could increase burden and costs for the patients, especially when there are multiple comorbidities present. For that reason the question whether case management has any additional value over the structured diabetes management and if so, for which patients with comorbidity, is very important. This is also a core subject of the ZonMw research program on disease management, who provide funding for this study.
Secondly, the case manager in our study is less extensively involved in coordinating the patients' care than in the USA and for example does not coordinate transitions between sites (from hospital back to home or vice versa). When a patient is in hospital, the case manager will be informed by the patient, family or hospital. The case manager will contact the patient when he or she is still in hospital or after discharge to discuss and, if necessary, adjust the care plan. Participants in this study are not institutionalized. They are motivated and empowered during this intervention to contact the case manager if problems or changes in health status occur. Important is the emphasis on patient priorities and patient self management, monitored by monthly telephone contacts, which also implies that patients are responsible for keeping the case manager up-to-date.
Thirdly, we do not include training for the patient's informal caregivers, because the participants in this study are expected not to be severely frail. We are aware of the burden informal caregivers often face and therefore they are welcome to accompany their spouses during their participation in the case management program.
This study had some limitations in the design that might influence the reliability and validity of this study, which we have to address.
Our study population is a standardized group of T2DM patients already receiving structured diabetes care in a diabetes management program.
This could influence the external validity of the study. However at this moment the majority of the T2DM patients in the Netherlands are included in a disease management program, which means that structured diabetes management is more or less 'usual care' in primary care. Therefore we expect our study results to be generalizable, meaning it can be translated to a larger group of comorbid diabetics in the Netherlands.
We look at the additional value of the case management program next to an existing disease management program. This means that using a selected standardized population has its benefits. The patient's health is monitored every 3 months at the GP and the information in the medical records should be up-to-date.
We identify possible participants by reviewing the electronic medical record at the general practice, using disease specific (ICPC) codes. Mental illnesses such as depression are often not well recognized or diagnosed in primary care. We might miss out on patients with this condition. We expect that most participants in this study will receive the case management program tailored to somatic disorders.
In this study we trained two Practice Nurses to conduct the program. They will include 230 participants in this study, which means a caseload of 115 participants per person - half enrolled in the intervention group and half receive usual care. These participants are divided over multiple primary care practices. Differences in results between participants managed by the case managers can occur. To avoid bias due to the number of case managers we will check the data for cluster-effect by case manager.
The case managers work together with the PN and GP to discuss the results from the initial assessment and during the design of the care plan before it is presented to the patient. During this contact the GP and PN might get motivated to use specific elements in the usual care group, who do not receive the intervention. This could lead to contamination. However, the GP and PN are not involved in the program (the actual problem assessment with the patients, the monthly monitoring, the contacts between the case manager and participant) and therefore we expect this form of contamination, if it occurs, will be washed out in a short period and will not influence the intervention effect after 12 months.
This study started in October 2009 by designing the program and making all practical arrangements for the start and implementation of the intervention. In February 2011 the first patients were included in the study. Follow-up of patients will continue until July 2012.
The results of this study will become available at the beginning of 2013.