Shared Decision-Making in Patients With Type 2 Diabetes

ABSTRACT: In shared decision-making (SDM), clinicians, diabetes educators, and other members of the health care team elicit perspectives and priorities of the patient and present options and information so that the patient can participate more actively in care. In patients with type 2 diabetes (T2D), the value of SDM has been evaluated in 5 randomized, controlled trials, each focusing on the utility of decision aids (eg, pamphlets, interactive web-based materials) that describe the benefits, risks, costs, and practical complexities of individual treatment options. Use of decision aids resulted in a number of statistically significant benefits on various psychometric measures, including increased knowledge, more realistic expectations, lower decisional conflict, and more autonomy in decision-making. Use of decision aids did not correlate with increased medication adherence rates or improved glucose control, although larger and longer studies are currently under way to examine these potential benefits in more detail. The demonstrated psychological and emotional benefits of SDM in patients with T2D are an important element of the patient-centered care approach, which seeks to ensure that clinicians are respectful of and responsive to individual patient preferences, needs, and values.

KEYWORDS: Type 2 diabetes, shared decision-making, patient-centered care

An estimated 29.1 million people in the United States have diabetes, equivalent to 9.3% of the total population.¹ Randomized, prospective clinical trials have shown that reducing blood glucose levels in patients with diabetes significantly improves both microvascular outcomes (eg, microalbuminuria) and macrovascular outcomes (eg, major cardiovascular events).^2-10

Nevertheless, a high proportion of patients fail to consistently achieve blood glucose targets recommended by expert guideline committees.^11-14 Consequently, many patients can experience up to years of insufficiently controlled hyperglycemia,¹⁵ significantly raising their risk of poor outcomes.

The reasons underlying this problem are complex and may include clinical inertia on the part of the prescriber,¹⁶ but it is clear that one of the key determinants is suboptimal daily self-management decisions on the part of patients, including poor adherence to their prescribed therapeutic regimens.¹⁷

To address this issue, the American Diabetes Association (ADA), the American Association of Diabetes Educators, and the Academy of Nutrition and Dietetics recently released a joint position statement on diabetes self-management education and support (DSME/S).¹⁸ The statement, which focused on patients with type 2 diabetes (T2D; 90% to 95% of total diabetes cases¹), included an evidence-based algorithm for DSME/S that involved patient engagement, information sharing, psychosocial and behavioral support, integration with other therapies, and coordinated care. Studies have identified many benefits of DSME/S programs when they are put into operation, such as reduced hospital admissions and readmissions, greater improvements in glycated hemoglobin (A_1C) levels, reduction in the onset and/or advancement of diabetes complications, and improvements in quality of life.¹⁸

In the ideal situation, DSME/S is a multifaceted, holistic approach requiring close communication and collaboration among the clinical team, including the treating physician, diabetes educator, nursing staff, and nutritionist. One of the key elements of DSME/S is shared decision-making (SDM), a process whereby an educator helps the patient understand the available therapeutic options, including the benefits, risks, and impact on quality of life, and then encourages the patient to participate in clinical decision-making on the basis of his or her values and preferences.¹⁸

This review examines the evidence supporting SDM and concludes with a case study describing the challenges of and practical approaches for putting SDM into action.

Shared decision-making

The concept of patient-centered care, introduced in the landmark Institute of Medicine (IOM) report, Crossing the Quality Chasm,¹⁹ seeks to ensure that clinicians are respectful of and responsive to individual patient preferences, needs, and values. Central to this philosophy is SDM, which elicits patient perspectives and priorities and presents options and information so that patients can participate more actively in care.

As described in a recent review of the subject,²⁰ SDM is predicated on the belief that patients and clinicians are both experts. Specifically, the clinician is considered the expert on the evidence and medical aspects of the disease, whereas patients are experts on how they experience and live with the illness, what they value most in their lives, and how a certain course of action fits and might be implemented in their particular circumstance. The clinician’s role thus is to provide accurate information about available treatment options and expected outcomes and to assist the patient in developing a treatment plan tailored to his or her values, preferences, goals, and concerns. While SDM is widely endorsed by most medical organizations, it is underutilized in clinical practice.^21-24

In many ways, the complexities of T2D therapy are ideally suited for SDM. The overall goals of T2D therapy are to lower blood glucose, correct hyperlipidemia, and improve cardiovascular health, typically via lifestyle modification (diet and exercise) and pharmacotherapy.^22,25 Each of these treatment options requires careful consideration. Lifestyle modifications, in particular healthy eating and regular physical exercise, are known to be notoriously difficult to achieve. For instance, one meta-analysis involving 29 structured weight-loss programs found that overweight patients on very-low–energy diets regained 71% of their lost weight within 4 to 5 years, while patients on hypoenergetic, balanced diets regained 83% of their lost weight.²⁶

Fortunately, evidence indicates that DSME/S generally, and SDM specifically, can help patients sustain healthy behaviors needed to maintain glycemic control.^27-29 A meta-analysis of 31 randomized, controlled trials (RCTs) found that self-management education in adults with T2D reduced A_1C levels relative to control groups with no education by 0.76%, 0.26%, and 0.26% at immediate follow up, 1 to 3 months, and 4 months and more after the educational intervention, respectively.²⁹

Choosing pharmacotherapy for treating hyperglycemia also is complicated. At least 12 classes of glucose-lowering agents are available (biguanidines, sulfonylureas, meglitinides, thiazolidinediones, α-glucosidase inhibitors, dipeptidyl peptidase 4 [DPP-4] inhibitors, glucagon-like peptide-1 [GLP-1] receptor agonists, bile acid sequestrants, dopamine-2 agonists, sodium-glucose cotransporter 2 [SGLT-2] inhibitors, amylin mimetics, and insulins)^22,25 Each of these classes targets a dysfunction in one or more different tissues and organs affected by the disease (pancreatic β-cells, pancreatic α-cells, gastrointestinal tract, skeletal muscle, adipose tissue, liver, and kidney); moreover, each differs in its route of administration (oral vs injectable), frequency of administration (multiple times daily to once weekly), adverse effect profile (hypoglycemic episodes, weight gain or loss, etc.), and cost.

Because many patients are unaware of the complexities of T2D therapy, SDM may have a number of potential benefits on treatment. For example, although it has not yet been demonstrated in RCTs, nonadherence and/or overtreatment rates may be lower when misconceptions are eliminated and the patient better understands risk-benefit profiles. Similarly, quality of life in general may be higher when recommended treatment plans fit into a patient’s lifestyle. It would seem only reasonable, then, to integrate patients into treatment decisions whenever appropriate, given the importance of glucose control for optimal T2D outcomes.

Randomized Clinical Trials

The value of SDM has been evaluated in a number of RCTs, the gold-standard approach in evidence-based medicine. To date, most studies in the field have examined the utility of patient decision aids, usually consisting of pamphlets and/or interactive web-based materials that describe the benefits, risks, costs, and practical complexities of individual treatment options. The purpose of the decision aid is to present key clinical information to the patient in an easily accessible, didactic format, thereby facilitating the consultation dialogue. According to a Cochrane Collaboration review of 115 studies involving 34,444 participants (most not directly involving patients with T2D), the use of patient decision aids for a range of preference-sensitive decisions led to increased knowledge, more accurate risk perceptions, a greater number of decisions consistent with patients’ values, a reduced level of internal decisional conflict for patients, and fewer patients remaining passive or undecided.³⁰

In patients who have T2D, the utility of decision aids has been assessed in 5 RCTs^31-35 and is currently under study in at least 8 more.^36-43 Mullan and colleagues³⁴ performed a 6-month cluster-randomized trial that compared patients (n = 37) who received a standard educational pamphlet with patients (n = 48) who received Diabetes Medication Choice, a web-based decision aid that describes 5 antihyperglycemic drugs, their treatment burden (adverse effects, administration, and self-monitoring demands), and impact on A_1C levels (Figure 1; https://diabetesdecisionaid.mayoclinic.org/index.php/site/index). Overall, patient self-reports indicated that Diabetes Medication Choice was viewed as being more helpful than the usual educational packet (clustered-adjusted mean difference [AMD] in a 7-point scale, 0.38; 95% confidence interval [CI], 0.04-0.72). Patients who used Diabetes Medication Choice also exhibited improved knowledge (AMD, 1.10 of 10 questions; 95% CI, 0.11-2.09) and had more involvement in making decisions about diabetes medications (AMD, 21.8 of 100; 95% CI, 13.0-30.5). Similar benefits were observed in patients with T2D who received Statin Choice (https://statindecisionaid.mayoclinic.org), a decision aid that presents the estimated 10-year cardiovascular risk, absolute risk reduction with use of statin drugs, and disadvantages of using statin drugs.^32,35 Both the Diabetes Medication Choice and Statin Choice decision aids improved decisional outcomes not only in academic settings, but also in nonacademic and rural primary care practices.³¹

Figure 1. The Diabetes Medication Choice decision aid cards, available at http://shareddecisions.mayoclinic.org/decision-aid-information/ decision-aids-for-chronic-disease/diabetes-medication-management/.

In another cluster-randomized trial, Mathers and colleagues³³ compared the PANDAs decision aid to usual care in patients with T2D (https://www.sheffield.ac.uk/medicine/research/aupmc/pandas/welcome). In this study, the 95 patients who received PANDAs (compared with 80 controls) had lower total Decisional Conflict Scores (17.4 vs 25.2, P < .001); better knowledge (51.6% vs 28.8%, P < .001); more realistic expectations (risk of “hypo,” 81.0% vs 5.2%; “weight gain,” 70.5% vs 5.3%; and “complications,” 26.3% vs 5.0%, P < .001); and were more autonomous in decision-making (64.1% vs 42.9%, P = .012).

By the standards in the IOM report,¹⁹ the results of these RCTs demonstrate that decision aids significantly improve quality of care and hence should be integrated into clinical practice for patients with T2D. However, the clear psychometric benefits observed in these T2D studies did not translate into significant improvements in medication adherence or A_1C levels relative to usual care.^31-35 A number of reasons have been posited for this, including that the studies were short in duration, that they had relatively few participants and thus were statistically underpowered, and that selection bias resulted in control subjects who were more adherent and motivated than a typical population of patients. Further studies will be needed to better define how a greater sense of agency on the part of the patient with T2D ultimately affects long-term outcomes.

Putting SDM Into Practice

Central to the SDM approach in the treatment of patients with T2D is the consultation between clinician and patient, when a therapeutic strategy is discussed collaboratively and agreed upon (Figure 2). Notwithstanding the apparent simplicity of this approach, SDM can present implementation challenges in routine clinical practice. A recent summary of studies identified the following barriers against SDM implementation on the part of clinicians: lack of knowledge and misconceptions about the nature of SDM, a disconnect between perceived vs actual implementation of SDM principles in their current practice, concerns about insufficient time for SDM, lack of fit into organizational routines, and a prevailing uncertainty as to the value of empowering patients.²⁰ A meta-analysis of 38 SDM trials found that the 3 most often reported barriers were time constraints (22/38), lack of applicability due to patient characteristics (18/38), and the clinical situation (16/38), whereas the 3 most often reported facilitators were motivation (23/38), positive impact on the clinical process (16/38), and positive impact on patient outcomes (16/38).²¹

Figure 2. Shared decision-making model, modified from Tamhane et al.²⁰

Time constraints consistently come up as a key barrier to SDM. Many clinicians feel they do not have enough time during the clinical encounter to ensure that patients can comprehend the information provided and assist in selecting the best option for their care. Some of this resistance may reflect misconceptions. For instance, in another meta-analysis, decision aids were found to increase the length of consultation by a median of only 2.55 minutes (varied in individual studies from 8 minutes shorter to 23 minutes longer), indicating the additional time necessary to review a decision aid does not have to be onerous.³⁰ Nonetheless, the emotional and cognitive load following a diagnosis of diabetes can be overwhelming, and patients often need time to process the information about their condition and the treatment options available to them. Support staff can be very important to mitigate this issue. Ideally, integrating SDM into clinical practice should involve referral to a diabetes educator, who can implement diabetes self-management education programs and present options and information so that patients can participate more actively in their care.^44,45

An SDM Case Study

EV is a 45-year-old woman with T2D who arrives for a follow-up visit 1 week after an A_1C measurement of 8.6%. Her blood glucose log shows morning fasting glucose levels ranging from 120 mg/dL to 150 mg/dL and postprandial readings of 190 mg/dL to 220 mg/dL. She has been adherent with sitagliptin 50 mg and metformin 1000 mg twice daily, but she reports that her home blood glucose readings have been creeping upward.

Her current vital signs are as follows: blood pressure, 122/76 mmHg; heart rate, 82 beats/min; respiratory rate, 18 breaths/min; and temperature, 36.7°C. She is 165 cm tall and weighs 89 kg (body mass index, 32.6 kg/m²). She denies polyuria, polydipsia, or blurry vision. On physical examination, the lungs are clear to auscultation, the heart has a regular rate and rhythm without murmurs, and the abdomen is nontender. Peripheral pulses are normal, and there is no lower extremity edema. The foot examination shows normal sensation to light touch and no skin or toenail lesions. Results of the review of systems are unremarkable.

For her history, EV had been diagnosed 5 years ago with T2D. At diagnosis, she had an A_1C of 10.5%, a random glucose level of 276 mg/dL, polyuria, and blurry vision. She was started on a regimen of sitagliptin 50 mg/metformin 500 mg twice daily, and within 3 months her A_1C had dropped to 8.6%. The metformin was increased to 1000 mg twice daily, and her A_1C dropped even further to 7.2%. She has not had any hypoglycemic episodes, nor has she gained or lost significant weight since diagnosis. EV also has a history of hypertension (treated with lisinopril, 40 mg daily), dyslipidemia (treated with atorvastatin, 20 mg daily), and gastroesophageal reflux disease (treated with omeprazole, 20 mg daily).

Emotionally, EV is frustrated because she has maintained good glycemic control over the last 4.5 years by adhering to her medication regimen and increasing her physical activity (walking 15-30 minutes each day), although she admits to a few dietary indiscretions such as occasionally having multiple servings of dessert with friends. Upon discussion, she appears disheartened and evinces resistance to taking insulin.

“I know that I will have to take more medication,” she says. “I prefer another pill—no insulin. I feel terrible. I don’t know what I did wrong.”

Treatment Plan

The ADA recommends a target A_1C of less than 7.0%, fasting glucose less than 130 mg/dL, and postprandial glucose less than 180 mg/dL for most patients.²² A more ambitious A_1C target of 6.0% to 6.5% may be appropriate for patients with a long life expectancy and no cardiovascular disease, provided that this can be achieved without adverse effects such as severe hypoglycemia.

On the other hand, a target A_1C of 7.5% to 8.0% may be suitable for patients with significant comorbidities, limited life expectancy, and a history of severe hypoglycemia. The latter goal also is reasonable for patients who have not been able to reach lower A_1C levels with multiple diabetes medications and extensive education about diabetes self-management.

Given EV’s overall health profile, her target is an A_1C level of less than 7.0% or eventually even 6.0% to 6.5%. EV may require insulin replacement to achieve these goals, based on previous studies on the natural history of the disease. In one study,⁴⁶ for instance, individuals considered to be only on the high end of normal glucose tolerance exhibited more than a 50% decline in their acute plasma insulin response to a glucose challenge, while individuals with prediabetes manifested a delayed and severely impaired acute plasma insulin response. Thus, the ADA-recommended A_1C target of 6.5% to 7.0% might only be achievable in EV’s case with exogenous insulin therapy, given what is likely to be her severely compromised β-cell function.

EV’s resistance to taking insulin is therefore an issue. As described in a previous review,⁴⁷ patients with T2D can have disproportionate concerns, misconceptions, and fears about insulin that act as barriers to initiating or adhering to insulin therapy. Mainly these involve fear of injection, weight gain, and hypoglycemia, as well as the misconception that their T2D has worsened or that the need for insulin therapy reflects a personal failure at self-management (as in EV’s case). Thus, a simple but likely beneficial first step would be to reassure EV that she has done an effective job in managing her diabetes, and that her A_1C increase reflects the progression of the disease, not neglect on her part. Another barrier may involve the complexity of disease management, which includes lifestyle changes and intensive treatment regimens, and concerns regarding stigmatization by family, friends, and coworkers.

Working With the Patient

According to the principles of SDM, EV’s perspectives and priorities should be factored into all treatment decisions, and it should be acknowledged that concerns regarding insulinogenic weight gain and hypoglycemic episodes are reasonable. As the expert on disease-related issues, it is appropriate for the clinician to advocate insulin replacement against a patient’s wishes if that is the evidence-based optimum treatment option. To do so, the provider should elicit what EV knows about oral antidiabetic agents and insulin therapy and correct any misconceptions. This discussion might list and describe the options available to the patient and their benefits, risks, and practical issues (route of administration, frequency of administration, efficacy in reducing A_1C, potential to cause hypoglycemia, potential to induce weight gain, other side effects, and cost). By the end of the discussion, it is hoped that EV will accept on her own volition that insulin replacement is the most optimal course in her particular case.

However, if EV remains adamant against this strategy, it may be appropriate to consider another noninsulin medication. In their published guidelines, the ADA recommends that patients who lose glycemic control on dual therapy can intensify treatment to triple therapy, so long as the new drug comes from a different class of glucose-lowering agent.²² If EV had been on metformin and, for instance, a sulfonylurea, it might then have been appropriate to consider a DPP-4 inhibitor or a GLP-1 receptor agonist, since incretin therapies are from a different class. Since EV is on metformin and sitagliptin, adding a thiazolidinedione or an SGLT-2 inhibitor, for example, might be considered. It should be explained to EV that when the triple therapy ultimately fails, the next step must be insulin replacement, which may prepare the ground for her future acceptance of insulin as a therapeutic option.

Respecting the Patient

The key point in this case study is that SDM requires a good-faith effort on the part of clinicians to respect patient perspectives. In some scenarios, as with EV, 2 or more therapeutic options may be available, and eliciting patient involvement in these circumstances can have multiple benefits. To date, these benefits have been identified in RCTs mainly on various psychometric measures, such as increased knowledge, more realistic expectations, lower decisional conflict, and more autonomy in decision-making, rather than increased medication adherence rates or improved glucose control. Nonetheless, the increased sense of involvement on the part of the patient from SDM is central to the concept of patient-centered care, which seeks to ensure that clinicians are respectful of and responsive to individual patient preferences, needs, and values.

Eva Vivian, PharmD, MS, is a professor in the School of Pharmacy at the University of Wisconsin in Madison.

Financial Disclosure: Dr Vivian reports no nonfinancial or commercial, proprietary, or financial interest in the products or companies described in this article manuscript and did not receive grants or a consultant honorarium to write the manuscript or otherwise assist in its development.

Funding/Support: Medical writing support for this work was provided by David Norris, PhD, of Ecosse Medical Communications and was funded by AstraZeneca.

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