In this large, unselected cohort of low-income primary care patients with diabetes, attending at least one visit devoted specifically to patient education was associated with significantly lower rates of hospitalization and hospital charges. Having had any educational visit, as opposed to none, was associated with 8 fewer hospitalizations per 100 person years; each educational visit was associated with $1,684 less in total hospital charges per patient over the course of follow-up.
Other investigators have found that diabetes education was associated with decreased hospital admissions in trials in managed care organizations (8
) and mixed-income primary care systems.(7
) A small program for Medicaid recipients in Arkansas found that over a one year time period participants had an estimated 0.37 fewer hospital admissions after adjustment for demographic variables, prior drug treatment, and prior period Medicaid costs. Total Medicaid expenditures, including the costs of the diabetes education program, were not significantly different from those of non-participants.(9
Our finding that individual nutritionist visits were more strongly associated with improved outcomes than were group diabetes classes differs from most other studies (13
) Most studies that have compared group with individual diabetes education strategies have found equivalent outcomes, with some finding improved short-term intermediate outcomes for group participants.(14
) Greisinger, et al., found that diabetes classes were associated with improved outcomes but individual sessions with a Certified Diabetes Educator were not.(7
) The difference in our findings may reflect differences in the specific services offered or in the time period. Our study covered hospitalizations 1993−2001, while Greisinger, et al., assessed hospitalizations in 2002. Alternatively, the inner-city, low-income patients served by the PHCCs may respond differently to these services than higher-income patient populations, or nutritionists in this public health system may have been more focused on the educational needs of patients with diabetes than most clinicians in other health care systems. A review of interventions designed to improve diabetes care for socially disadvantaged populations identified one-on-one interventions with individualized assessment and reassessment as one of the features associated with the most positive effects (15
) and patients with low literacy were found to derive greater benefits in an assessment of a disease management program emphasizing one-on-one counseling.(16
) Our findings are consistent with the evidence that group-based diabetes education results in better outcomes than “usual care,” or no formal diabetes education.(17
Most other studies of diabetes education have included only intermediate clinical outcomes such as glycemic control, cholesterol levels, and body mass index, and have included relatively short follow-up periods. Some studies suggest that the intermediate clinical effects of diabetes education on these intermediate outcomes declined substantially within a few months after the end of the intervention.(18
) This study offers additional evidence that participation in diabetes education is associated with significant differences in important clinical outcomes over a mean 4.7 year follow-up period.
As with any observational study, our analyses are vulnerable to confounding. Diabetic patients who attend educational visits may be systematically different from those who do not, in ways that are associated with improved outcomes. However, we did find that in this patient population, patients with comorbid conditions were more likely than other patients to have had an educational visit, suggesting that the factors influencing selection into the “intervention” group were not one-sided. In addition, we controlled for a wide range of baseline clinical factors, including the number of hospitalizations recorded prior to the diabetes diagnosis as well as major comorbid diagnoses. We also controlled for the number of primary care visits other than educational visits each patient had during the course of followup as an indicator of patient engagement and access to care. This variable was also strongly associated with better patient outcomes, and was responsible for much of the attenuation of the education effects seen in the adjusted models. Although residual confounding associated with patient characteristics could still have affected the results, inclusion of these patient variables substantially reduces the magnitude of any remaining bias.(19
Patients who received educational visits were more likely to be between the ages of 45 and 64 at baseline than were those who did not. However, restricting the analyses to this age group did not alter the conclusions.
Patients were offered one type of education or the other based on what was available at that time at the health care center they attended. Confounding by indication is unlikely to occur in this situation,(20
) although we cannot exclude the possibility that the availability of diabetes education classes was associated with other factors that affected outcomes. The finding that nutritionist visits had a stronger association with hospital admissions and charges than diabetes classes is strengthened by its robustness irrespective of the model used. There is no reason to believe that patients were selected into one or the other type of visit based on their preexisting characteristics. None the less, we cannot rule out the possibility that our findings are vulnerable to selection bias.
Our analyses are based on administrative data, which are prone to error, and did not include some important clinical variables, such as body mass index, blood pressure, or glucose values. The data are, however, not subject to biases associated with self-reporting of health care use. Although the long time period covered allows us to examine outcomes over a mean 4.7 years of follow-up, the availability and content of diabetes education was not uniform throughout the period and does not reflect more recent practices.
These data reflect outcomes not in a controlled clinical trial environment but in the real-world practice of a large, urban public health care system. Outcomes were hospital admissions—a clinical event representing substantial patient morbidity and burden—and hospital charges. The finding that, for this large population, attendance at even one educational visit was associated with substantially reduced hospitalization rates and hospital charges provides important evidence that providing formal diabetes education is an important and cost-effective imperative in primary care settings.
We have no data on how many patients were offered diabetes education but did not take advantage of it. This occurs frequently (21
), although there are few data available on patient recruitment to diabetes education outside of the research setting. This problem may be especially severe for low-income and less-educated patients.(23
) A program offered to 1968 eligible Medicaid patients in Arkansas succeeded in enrolling only 212 patients.(9
) Retention of patients in diabetes education programs that involve multiple sessions is also problematic.(9
) The finding that any type of educational visit was beneficial suggests that health care providers will do well to provide diabetes education in whichever format providers can support and patients will attend. The ideal form of diabetes education may well vary between systems and between patient populations. These findings underscore the importance of focusing on both feasibility for health care systems and acceptability to patients (or “adoption” and “reach,” in the “RE-AIM” evaluation framework) in designing and evaluating educational interventions.(21
Our most important finding is that either diabetes classes or nutritionist visits in any quantity were strongly associated with reductions in patient hospitalizations in hospital charges. The average annual hospital charges for patients who received any educational visit were $6,244, 39% less than the $10,258 per year average for patients who had no such visits. If the proportion of diabetic patients receiving education could be raised to the Healthy People 2010 goal of 60%,(3
) the data suggest that tens of millions of dollars in hospital charges and tens of thousand of hospitalizations could be avoided each year, just among patients of one large primary care system. Many safety-net providers find that obtaining payment for diabetes education from insurers is so burdensome that the payments do not effectively compensate for the effort required.(25
,26) Both public and private insurers would be well advised to invest in efforts to improve the “reach” of diabetes education in order to reduce both long-term costs and human suffering for the large and growing population of patients with diabetes.