Diabetes: Disease Management Programs

The Task Force finding is based on evidence from a systematic review of 27 studies (search period through December 2000). The review was conducted on behalf of the Task Force by a team of specialists in systematic review methods, and in research, practice, and policy related to diabetes prevention and control.

Twenty-seven studies qualified for the review.

• Glycated hemoglobin (GHb) levels: 0.5 percentage point median decrease (Interquartile Interval [IQI]: -1.35% to -0.1%; 19 studies)
• Monitoring by healthcare providers improved for several diabetes-related conditions:
  • GHb levels: median net increase of 15.6% (IQI: 4% to 39%; 15 studies)
  • Lipid concentrations: median increase of 24.0% (IQI: 21% to 26%; 9 studies)
  • Retinopathy: median increase of 9.0% (IQI: 3% to 20%;15 studies)
  • Urine protein: median increase of 9.7% (IQI: 0% to 44%; 7 studies)
  • Foot lesions and peripheral neuropathy: median increase of 26.5% (IQI: 10.9% to 54%; 9 studies

Two economic studies were included in this review.

• The first study, conducted in Scotland, reported the average cost for adult patients of an integrated care disease management intervention versus traditional hospital clinic care.
  • Annual average adjusted costs were $143 to $185 for integrated care and $101 for traditional care, resulting in a higher annual average cost for the intervention of $42 to $84.
  • After two years no significant difference was seen between the two groups for GHb, body mass index, creatinine, or blood pressure.
  • Integrated care patients had higher annual rates compared with the traditional care group for routine diabetes care visits (5.3 versus 4.8) and screening and monitoring of GHb (4.5 versus 1.3), blood pressure (4.2 versus 1.2), and visual acuity (2.6 versus 0.7).
• The second study was a cost–benefit analysis of preconception plus prenatal care versus prenatal care only for women with established diabetes. No effect size was determined, as this was a modeling study relying on secondary data.

Based on results for interventions in different settings and populations, findings are applicable to adults with either type 1 or type 2 diabetes treated in community clinics and managed care organizations in the U.S. and Europe. It is not clear how well these findings apply to treatment in other settings.

CPSTF identified several areas that have limited information. Additional research and evaluation could help answer the following questions and fill remaining gaps in the evidence base. (What are evidence gaps?)

The following outlines evidence gaps for disease and case management interventions to control diabetes.

Even though disease and case management were found effective in the managed care setting for improving glycemic control and provider monitoring of certain important outcomes, several important evidence gaps were identified in this review. One of the most pressing needs is to better define effective interventions. Disease management has multiple component interventions. To make optimal use of resources, however, only the interventions that contribute most to positive outcomes should be implemented, and these need to be defined. Case management interventions are also usually delivered with other interventions, and the effectiveness of these also needs to be defined. Are case management interventions delivered with disease management more effective than case management delivered as a single intervention? Are there specific additional interventions that augment the effectiveness of disease and case management, such as DSME? Additional research questions relating to case management include identifying the optimal intensity (frequency and duration) of patient contact and determining whether professionals other than nurses (e.g., social workers or pharmacists) could function as case managers.

How best to integrate disease and case management interventions into existing healthcare systems also needs to be addressed. What are the strengths and limitations of delivering these interventions as part of primary care or specialty care, or might they best be delivered by contracted organizations and provider networks that are separate from the patient’s healthcare delivery system (i.e., the carve-out model)?

Although the existing effectiveness literature examines many important outcomes, research is needed to determine the effect of disease and case management on long-term health and quality of life outcomes, including cardiovascular disease events, renal failure, visual impairment, amputations, and mortality. Further work is also needed to determine the effect of case management on blood pressure, weight, lipid concentrations, and provider screening rates for retinopathy, peripheral neuropathy, and microalbuminuria. In addition, provider and patient satisfaction with these interventions need much more attention from researchers.

As discussed above, the applicability of these data are somewhat limited, leaving numerous important questions unanswered. For example, are disease and case management effective in settings other than HMOs and community clinics, such as academic clinics and independent private practices? Do these interventions work better in some types of delivery systems than others? Are they effective for adolescents with diabetes? How do the cultural, educational, and socioeconomic characteristics of a population affect outcomes? What are the key barriers that providers perceive for disease and case management? How would it be best to obviate them? Do patients perceive any barriers to these interventions?

Numerous deficiencies in the methodologies of these studies were identified. Often there was inadequate descriptive information; studies need to include adequate demographic information (at a minimum, age, gender, race or ethnicity, and type of diabetes), a description of the delivery system infrastructure (automated information systems, prior use of guidelines, resource support, management [medical and non-medical] commitment and support), and details of the intervention (components, frequency and duration of patient contact, who delivered the intervention, whether and which clinical practice guidelines were used, and degree and type of interface with primary care). In addition, more studies are needed with a concurrent comparison group to control for secular trends in healthcare delivery and patient practices. Finally, studies are needed in which a broad range of providers is recruited.

• Almost all of the included studies evaluated interventions conducted in community clinics or managed care organizations. The managed care organizations included network or primary care-based models and staff or group model HMOs.
• Studies generally involved the entire population of providers in a facility, although in some studies the researchers selected specific providers to participate, or the providers volunteered.
• Studies were conducted predominantly in urban centers in the United States and Europe.
• The body of evidence on disease management examined either adults with type 2 diabetes or populations with mixed type 1 and 2 (predominantly type 2).

Analytic Framework [PDF – 379 kB]

Summary Evidence Table — Effectiveness Review [PDF – 136 kB]

The number of studies and publications do not always correspond (e.g., a publication may include several studies or one study may be explained in several publications).

Acton K, Valway S, Helgerson S, et al. Improving diabetes care for American Indians. Diabetes Care 1993;16:372–5.

Aubert RE, Herman WH, Waters J, et al. Nurse case management to improve glycemic control in diabetic patients in a health maintenance organization. A randomized, controlled trial. Ann Intern Med 1998;129:605–12.

Carlson A, Rosenqvist U. Diabetes care organization, process, and patient outcomes: effects of a diabetes control program. Diabetes Educ 1991;17:42–8.

Casey DE Jr, Egede LE. Effect of a disease management tool on residents’ compliance with American Diabetes Association standard of care for type 2 diabetes mellitus. American Diabetes Association. Md Med J 1999;48:119–21.

Chicoye L, Roethel CR, Hatch MH, Wesolowski W. Diabetes care management: a managed care approach. WMJ 1998;97:32–4.

Cook CB, Ziemer DC, El-Kebbi IM, et al. Diabetes in urban African-Americans. XVI. Overcoming clinical inertia improves glycemic control in patients with type 2 diabetes. Diabetes Care 1999;22:1494–500.

de Sonnaville JJ, Bouma M, Colly LP, Deville W, Wijkel D, Heine RJ. Sustained good glycaemic control in NIDDM patients by implementation of structured care in general practice: 2-year follow-up study. Diabetologia 1997;40:1334–40.

Deichmann R, Castello E, Horswell R, Friday KE. Improvements in diabetic care as measured by HbA1c after a physician education project. Diabetes Care 1999;22:1612–6.

Diabetes Integrated Care Evaluation Team. Integrated care for diabetes: clinical, psychosocial, and economic evaluation. BMJ 1994;308:1208–12.

Domurat ES. Diabetes managed care and clinical outcomes: the Harbor City, California Kaiser Permanente diabetes care system. Am J Manag Care 1999;5:1299–307.

Foulkes A, Kinmonth AL, Frost S, MacDonald D. Organized personal care—an effective choice for managing diabetes in general practice. J R Coll Gen Pract 1989;39:444–7.

Friedman NM, Gleeson JM, Kent MJ, Foris M, Rodriguez DJ, Cypress M. Management of diabetes mellitus in the Lovelace Health Systems’ EPISODES OF CARE program. Eff Clin Pract 1998;1:5–11.

Goldfracht M, Porath A. Nationwide program for improving the care of diabetic patients in Israeli primary care centers. Diabetes Care 2000;23:495–9.

Johnston C, Ponsonby E. Northwest Herts diabetic management system. Comput Methods Programs Biomed 2000;62:177–89.

Legorreta A, Peters A, Ossorio RC, Lopez R, Jatulis D, Davidson M. Effect of a comprehensive nurse-managed diabetes program: an HMO prospective study. Am J Manag Care 1996;2:1024–30.

McCulloch DK, Price MJ, Hindmarsh M, Wagner EH. A population-based approach to diabetes management in a primary care setting: early results and lessons learned. Eff Clin Pract 1998;1:12–22.

North Tyneside Diabetes Team. The diabetes annual review as an educational tool: assessment and learning integrated with care, screening, and audit. Diabet Med 1992;9:389–94.

O’Connor PJ, Rush WA, Peterson J, et al. Continuous quality improvement can improve glycemic control for HMO patients with diabetes. Arch Fam Med 1996;5:502–6.

Payne TH, Galvin M, Taplin SH, Austin B, Savarino J, Wagner EH. Practicing population-based care in an HMO: evaluation after 18 months. HMO Pract 1995;9:101–6.

Peters AL, Davidson MB. Application of a diabetes managed care program. The feasibility of using nurses and a computer system to provide effective care. Diabetes Care 1998;21:1037–43.

Rubin RJ, Dietrich KA, Hawk AD. Clinical and economic impact of implementing a comprehensive diabetes management program in managed care. J Clin Endocrinol Metab 1998;83:2635–42.

Sadur CN, Moline N, Costa M, et al. Diabetes management in a health maintenance organization. Efficacy of care management using cluster visits. Diabetes Care 1999;22:2011–7.

Sidorov J, Gabbay R, Harris R, et al. Disease management for diabetes mellitus: impact on hemoglobin A1c. Am J Manag Care 2000;6:1217–26.

Sikka R, Waters J, Moore W, Sutton DR, Herman WH, Aubert RE. Renal assessment practices and the effect of nurse case management of health maintenance organization patients with diabetes. Diabetes Care 1999;22:1–6.

Sperl-Hillen J, O’Connor PJ, Carlson RR, et al. Improving diabetes care in a large health care system: an enhanced primary care approach. The Joint Commission Journal on Quality Improvement 2000;26:615–22.

Taplin S, Galvin MS, Payne T, Coole D, Wagner E. Putting population-based care into practice: real option or rhetoric? J Am Board Fam Pract 1998;11:116–26.

Tom-Orme L. Chronic disease and the social matrix: a Native American diabetes intervention.Recent Adv Nurs 1988;22:89–109.

Varroud-Vial M, Mechaly P, Joannidis S, et al. Cooperation between general practitioners and diabetologists and clinical audit improve the management of Type 2 diabetic patients.Diabetes Metab 1999;25:55–63.

Economic Review

Diabetes Integrated Care Evaluation Team. Integrated care for diabetes: clinical, psychosocial, and economic evaluation. Br Med J 1994;308:1208–12.

Elixhauser A, Weschler JM, Kitzmiller JL, et al. Cost-benefit analysis of preconception care for women with established diabetes mellitus. Diabetes Care 1993;16:1146–57.

The following outlines the search strategy used for the systematic reviews of case management interventions and disease management programs to prevent and control diabetes.

The scientific literature was searched through December 2000 by using the MEDLINE database of the National Library of Medicine (started in 1966), the Educational Resources Information Center database (ERIC, 1966), the Cumulative Index to Nursing and Allied Health database (CINAHL, 1982), and Healthstar (1975).

The medical subject headings (MeSH) searched were diabetes, case management, and disease management, including all subheadings. Text word searches were performed on multiple additional terms, including care model, shared care, primary health care, medical specialties, primary, or specialist.

Abstracts were not included because they generally had insufficient information to assess the validity of the study using Community Guide criteria. Dissertations were also excluded, because the available abstracts contained insufficient information for evaluation and the full text was frequently unavailable.

Titles of articles and abstracts extracted by the search were reviewed for relevance, and if potentially relevant the full-text article was retrieved. We also reviewed the reference lists of included articles, and our consultants provided additional relevant citations.

To be included in the review, studies had to be primary investigations of interventions selected for evaluation; be conducted in Established Market Economies; provide information on one or more outcomes of interest; and meet minimum quality standards. All types of comparative study designs were included, including studies with concurrent or before-and-after comparison groups.

The following considerations are drawn from studies included in the evidence review, the broader literature, and expert opinion. The Community Guide does not conduct systematic reviews of implementation.

• Disease management can be combined with interventions that focus on the patient or population (e.g., diabetes self-management education), the provider (e.g., reminders or continuing education), or the healthcare system or practice (e.g., practice redesign).
• The organized and evidence-based approach to care can be extended to other diseases and healthcare needs in an organization. The same kind of infrastructure that supports diabetes disease and case management interventions, including information systems, practice guidelines, and support staff training and resources, could be used for the care of people with cardiovascular disease, mental health disorders, or chronic pain or for the delivery of preventive services (e.g., immunization of adults and children by using registries and reminder/recall systems).
• Organizations may lack the leadership to support these interventions and the financial resources needed for implementation and maintenance, or they may lack practice guidelines and the necessary skills and resources to develop guidelines. Several practice guidelines are publicly available, however, such as those published annually by the American Diabetes Association.
• Providers can find disease management time-consuming, particularly initially, and they can be inexperienced or uncomfortable with information systems. In addition, there may be little or no reimbursement for delivering patient reminders and other proactive care strategies.
• It can be difficult for healthcare providers to switch from a traditional mode of reactive care to a proactive, organized management. Changes may need to be made to their approach to patient care, such as  appointment and follow-up scheduling; allocation of clinic time to review registries and practice guidelines; delineation of the roles of support staff and providers; the delegation of care traditionally performed by physicians to other professionals, such as nurses; team organization; and the use of planned visits and patient reminders.
• Identifying patients to participate in these interventions may be difficult. Patients can be identified from provider and staff memory, hospital discharge summaries, claims data, visit encounter forms, laboratory test results, patient-initiated visits, or pharmacy activity.
• Patient barriers include difficulties in maintaining healthy lifestyles and the complexity of self-management required for diabetes management.

Healthy People 2020

Healthy People 2020 includes the following objectives related to this CPSTF recommendation.

• Diabetes, Objective 5 (D-5): Improve glycemic control among persons with diabetes
• Diabetes, Objective 6 (D-6): Improve lipid control among persons with diagnosed diabetes
• Diabetes, Objective 9 (D-9): Increase the proportion of adults with diabetes who have at least an annual foot examination
• Diabetes, Objective 11 (D-11): Increase the proportion of adults with diabetes who have a glycosylated hemoglobin measurement at least twice a year
• Diabetes, Objective 12 (D-12): Increase the proportion of persons with diagnosed diabetes who obtain an annual urinary microalbumin measurement