Although over 10 million Americans are under treatment for type 2 diabetes mellitus, there is virtually no information on how treatments for hyperglycemia are viewed by patients or what preferences they place on competing treatment options. Improved understanding of the balance between benefit and burden is vital if we are to optimize diabetes care.
The study evaluates preferences using self-administered surveys, interactive computer-based interviews, and semi-structured patient interviews. The objectives are: (1) to characterize patient preferences for different modes of therapy; (2) to determine if patients can be divided into distinct groups or clusters based upon how they rank the treatments when presented with treatment benefits; and (3) to describe quantitatively the relationship between benefits, burden, and treatment choice.
This project is a cross-sectional study. Willing participants completed surveys that offer insight into the factors that affect treatment preferences in type 2 diabetes. Patient ratings of different aspects of treatment will be compared, and factors that may influence these ratings will be examined. Patients will also be asked to rank treatments considering both burden and projected benefit. Subjects will be classified into groups based upon the factors (burden, benefit, or a combination) that influence their treatment rankings. Multinomial logistic regression will be used to analyze these factors while controlling for covariates such as demographics.
The focus group results suggest that there are several barriers to compliance with therapy. Compliance with diet is most significantly restricted by the cost of following prescribed diets, by portion size, and by difficulty with family support. In the urban setting, communication with providers was a major barrier to compliance, as providers did not understand social and cultural climate. In contrast, compliance with insulin therapy was limited by a much broader range of concerns, including communication with providers, fear of needles, the emotional impact of insulin injections, confusion over how to use insulin, and the difficulty and inconvenience of insulin injections.
On the written survey, ratings for dislike of therapies ranged from 1.44 for oral agents to 4.78 for insulin 3-4 times per day. The best predictor of ratings of dislike was patients prior experience with a treatment, especially insulin. Demographic factors such as age, education, income, and race were not consistently associated with dislike. Ratings of dislike were associated with patients’ perceptions of glucose control, and were the best predictor of compliance.
The computer survey suggested that most (77%) of the patients can make consistent and rational choices about therapy. 27 percent of respondents did not vary in their treatment choices regardless of level of risk, suggesting a fixed preference that was either driven entirely by the burden of therapy or by risk of outcome. In general, increasing risk led to increasing likelihood of choosing more intensive and effective therapy; at low levels of risk, insulin was the first choice 19.0 percent of the time, while at high levels of risk, insulin was the first choice 58.2 percent of the time. This pattern suggests that patients do in fact consider risk of outcome and that they can make rational decisions about treatments.
Understanding the distribution of preferences allows us to better define the proportion of patients who are willing to undergo intensive therapy. Our preliminary data suggest that most patients can explicitly consider both burden and benefit, and that many are not willing to accept the treatment burden of insulin for the projected benefit. This has important implications for setting treatment guidelines and quality standards, designing less burdensome interventions, and for enhancing communication. The VA can use this information to better define its targets for quality of care for diabetes, a prevalent and costly condition.
- Vijan S, Hayward RA, Ronis DL, Hofer TP. Brief report: the burden of diabetes therapy: implications for the design of effective patient-centered treatment regimens. Journal of general internal medicine. 2005 May 1; 20(5):479-82.
- Vijan S, Stuart NS, Fitzgerald JT, Ronis DL, Hayward RA, Slater S, Hofer TP. Barriers to following dietary recommendations in Type 2 diabetes. Diabetic Medicine. 2005 Jan 1; 22(1):32-8.
- Stuart N, Vijan S, Ronis D, Hayward RA. Patient preferences for the care of diabetes. Paper presented at: Society of General Internal Medicine Annual Meeting; 1999 Apr 1; San Francisco, CA.