According to the Centres for Disease Control and Prevention (CDC) [1], chronic diseases such as diabetes, cardiovascular disease, asthma and cancer are the most common and costly health problems in America with an annual cost totalling $174 billion in 2007 [2]. Chronic diseases have been the leading causes of death and disability in the United States for the past decade. In 2005, diabetes was the sixth most common disease in the U.S., and over 14.6 million Americans suffered from diabetes and diabetes-related comorbidities, such as hypertension, stroke or infections of the kidney. However, studies have concluded that type 2 diabetes is preventable, and patients with the disease can have a higher quality of life without suffering the chronic situation of high health care expenditures, if they follow their physician's advice on diet, medicines, and lifestyle behaviours [3–5]. Disease management (DM) is a systematic approach to identify the population at risk for specific diseases, especially chronic diseases, and to intervene with a program of care. Many studies have confirmed that DM can improve the quality of life or outcomes of treatment, ensure patient satisfaction and control costs [6] by empowering patients through education to better manage their own illness.

Diabetes is prevalent in Louisiana, and management of the disease is challenging due to large low-income populations who may not follow guidelines strictly [7]. According to most studies, patients with type 2 diabetes receive better quality of care from primary care providers than those who seek services in ED. The Health Care Services Division (HSCD) of Louisiana State University is a key provider of care to the uninsured and Medicaid populations in Louisiana. LSU HCSD has implemented a comprehensive, evidence-based, diabetes disease management program to continuously improve diabetic care processes. In the diabetes management program, the components include evidence-based guidelines for physicians and establishment of actionable patient goals with education, medication and clinical support to improve patients' diabetes situations.

When diabetic patients choose the ED for their care, not only do they pay more with no guarantee of appropriate quality services (especially in non-urgent situations) [8–11], but also the health system consumes more resources. From the perspective of disease management, patients with less-urgent conditions in the ED can seek primary care instead. The primary objective of this study is to examine the likelihood that patients who are adhering to the DM program's clinic visit schedules will use the ED for less-urgent problems and conditions.

Patients with insurance coverage at the time of the visit had an increased likelihood of a less-urgent ED visit, ranging from 1.13 for being covered by Medicare, and 1.29 for Medicaid enrolees, to 1.70 for commercial insurance coverage as compared with those who were uninsured. Gender, comorbidity, experience of hospitalization in the prior year, and facility size were not statistically significant in predicting the odds that a patient would seek less-urgent care in the ED.

Diabetes DM programs are intended to improve health status and quality of life for type 2 diabetics and reduce costs by educating patients about the benefits of going to clinics and monitoring their disease conditions regularly [16, 17]. Other benefits arise from a successful DM program--namely patients who adhere to their DM program [18] or effectively manage their A1c reduce the likely usage of the ED care. Patients go to clinics for diabetes not only for check-ups but also to monitor their diabetes condition through foot and eye exams and to receive updated information to reduce the risk of complications.

Most studies agree that A1c is an important indicator of patient diabetes control. From this study, patients who maintain their A1c at closer to normal levels reduce their likelihood of less-urgent ED visits about 1.22 times. Further, patients who remain in the program longer have a decreased likelihood of less-urgent ED visits even though the effects are all slight. The reason is that, after checking the ED visits' distribution, the most less-urgent emergency situations usually occur during the patient's early visits, such as during the first or second year of the DM program. Aggressive case management to maintain patients' adherence and enhance communication with patients, especially in the first year, may reduce the possibility of future inappropriate ED visits.

In addition, most studies indicate differences in the prevalence of diagnosed diabetes between racial groups. African-Americans are more likely to have diabetes, experienced more complications and face unfavourable prognoses. In this study, African-Americans tended to use more ED services in less-urgent situations than other patients after controlling for insurance coverage, adherence and management of A1c levels. One possible reason may be that they lack access to sufficient primary care resources, resulting in use of less appropriate care from an ED, which may affect their diabetes outcomes.

The Charlson comorbidity index (CCI) did not provide significant information on ED visit use in this study. One reason is that patient visits associated with severe health conditions were more likely to be classified as urgent and thus dropped from the study [19, 20].

This study also triggered some interesting questions for future investigations in diabetes research. For example, according to other studies, uninsured patients are more likely to use the ED for care [21, 22]. In this study, the uninsured were less likely to seek care in the emergency department for less-urgent situations. A recent study also found that the uninsured do not use the ED more often [23]. We also examined the effect of a patient changing health plans during the study period on the likelihood of less-urgent ED visits, but this variable did not reveal any significant difference.

One of the reasons for patients with health coverage to use the ED for less-urgent visits may be the need to use after-hour services as well as the inability to get timely appointments at the clinic [24, 25]. In this study, we controlled for visits over the weekend when the clinics were closed, but could not control for evening visits during the week. Another reason that those with insurance coverage are more likely to use the ED for less-urgent visits may the effect of moral hazard on use. Health insurance reduces the out-of-pocket costs of seeking care in the ED. Some of uninsured may be held liable for the costs of the ED visit if they are not considered indigent [26]. Further study is required to examine the ED usage by insurance status to understand which strategy is suitable to implement in the future.

It seems likely that less-urgent ED visits can be reduced by improving efficiency in primary care by providing a call centre to arrange appointments or case managers to help patients better manage their conditions.

This study used rigid criteria to select the target study population. However, several limitations need to be mentioned. First, we used secondary data and some restrictions, such as the method of data collection, and the coding system, could not be changed. The second limitation is the data time frame. DMED established the data collection system in 1998, and we only selected patients who had medical records from 1999. However, this did not mean these DM programs across the state started at the same time, and some programs were in operation earlier than the start of DMED's implementation. In other words, some patients may have gone to LSU-HCSD (or to another provider for diabetes treatment) before 1998, which may have affected their behaviour during the period of the study. Additionally, some patients may have received some clinical procedures prior to the start date in this study or obtained care in other non-HCSD facilities. There was no information on utilization outside of the HCSD system to enable exclusion of these patients from this study. The third limitation is the behaviour of patients who were only in the DM program for a short duration -- less than one year. Patient attrition of non compliant patients may affect the likelihood of non-urgent ED visits when comparing those who have longer durations of care. The final limitation is a generalized application restriction. These research results apply only to the public system of care and may not be suitable for other health care organizations.

In this study, we assessed the factors that predispose or enable less-urgent ED visit use among a group of Type 2 diabetes patients seen within a disease management program. Our study provides an example in a natural environment rather than using a randomized controlled trial. The information from this study can help managers adopt strategies to reduce improper patient use of emergency services. Disease managers need to continually improve the clinical protocol that encourages patients to follow the guidelines for clinic visits and obtain regular laboratory tests and examinations. In particular, patients need to remain in their diabetes disease management programs over several years. Adherence to clinic schedules, including guidelines, is still the best way to reduce the likelihood of less-urgent ED visits. We suggest providing reminders for clinic visits, creating continuous care by calling patients regularly or using case managers to reduce the likelihood of less-urgent ED visits. The primary outcome from this investigation provides important information to identify the specific populations who are more likely to use less-urgent ED services. It also provides useful long-term suggestions for reducing the use of ED services while improving quality.