How Do We Evaluate Cardiovascular Risk in Diabetes?

Dennis P. Scanlon, PhD: When looking at the clinician of today versus the historical role of the clinician, you mentioned this broader care team and its importance. Are we doing enough to train the clinician today to think about care teams and to think about these other resources? Or what do we need to do?

Robert Gabbay, MD, PhD, FACP: I think it’s starting. In medical schools, there’s more interprofessional training, where budding physicians are working side-by-side with other team members and are learning that that’s the way to deliver care. But again, the old notion that the physician is the person that’s going to do everything is just impossible. You go to any primary care provider and they’re overwhelmed.

The answer is to be more team-based and to work with other members of the team and have everyone practice to the top of their license. It’s a more satisfying job for the people involved, and it allows more touches to the patient. For the person with diabetes, it’s really not about the 3, or 4, or 5 times, or even 6 times of visits to the physician. They need more touches to be able to keep them engaged because adherence is a challenge and some form of self-management support is really critical.

Dennis P. Scanlon, PhD: So, John, how do we pay for that? Medicare has determined that there’s some benefit in terms of the investment in new payment models relative to the expected outcomes. But representing a health plan, how are you guys thinking about this?

John A. Johnson, MD, MBA: On the managed care side, in the government-sponsored space, we offer case- and disease-management programs that are interdisciplinary teams that partner with the provider. For example, we may have a pharmacist, a nurse, a social worker, [or even] a community health worker who help us locate our members in the community who have diabetes and connect them to those resources. That is a benefit that we offer our most vulnerable at-risk members. In the commercial space, it’s generally offered to the employers as an add-on benefit as part of the coverage they provide to the members in their pane.

Zachary T. Bloomgarden, MD, MACE: But the dilemma of offering it to the most at-risk individuals is that two-thirds of Americans are overweight or obese. One-third are obese. So this has to be something that reaches the overall population. By the time people are at greatest risk (when they’ve developed already high levels of risk factors or they have existent cardiovascular disease), of course they still need this kind of intervention. But we really want to get them before that time.

John A. Johnson, MD, MBA: Absolutely. The focus should definitely be on prevention. But I think when you’re working with limited or finite resources, you want to target those resources to the most vulnerable members that you can impact and make a difference with the onset intent of lifestyle modification and enforcing the importance of improved quality.

Dennis P. Scanlon, PhD: So, Michael, as an endocrinologist, and because I’m hearing that the primary world is taking care of the bulk of the diabetes patients, maybe talk about how that relationship between endocrinology and primary care is and where you see it needing to continue to develop? And if you could also talk a little bit about the comorbidities and complications associated with diabetes, including cardiovascular risk?

Michael Gardner, MD: Sure. I think the role of the endocrinologist, now, is to take the most severely affected patients—the most complex patients—and to tune them up and return them to their primary care provider. But, we also need to be reaching out to the primary care providers and providing education on the fundamentals of diabetic care. Those include, as you mentioned, the associated complications that go with diabetes: the hypertension, the dyslipidemia, and then also the complications of diabetes.

The complications of diabetes break down into 2 fundamental categories: the microvascular complications and the macrovascular complications—the macrovascular being primarily heart disease, stroke, and heart failure. So, we need to be addressing those with different interventions, which I think is some of what we’re going to talk about.

Dennis P. Scanlon, PhD: Anybody else what to comment on that?

Robert Gabbay, MD, PhD, FACP: I might just comment a little bit around the ways in which specialists can interact with primary care providers. I think the new model, where we see a lot of examples, is that as specialists—as endocrinologists—we take care of the highest-risk patients and the most complex patients. We can guide primary care in how to deliver better care for the vast majority of their patients and, I think in essence, we have a responsibility to do so.

We have this specialized knowledge that we want to transmit, and that’s not just us. It’s diabetes educators going to their primary care, dietitians, or other folks within this concept of the medical neighborhood; primary care defined as a series of medical homes; and the medical neighborhood being all of the rest of us that are outside of primary care, but need to guide primary care to enable them to do a better job.

Michael Gardner, MD: Exactly. We have a program at the University of Missouri where we are reaching out once a week via teleconference. We have primary care providers calling in from all over the state with the identified cases. [We also have] discussions with our endocrinologists of how they would handle these cases, at least in theory, and provide very short segments of fundamentals of diabetes.

Zachary T. Bloomgarden, MD, MACE: I’d like to bring up one slightly different version of this idea that there are different complications. There are probably different gradients of the relationship between diabetes and outcomes of different complications.

So for microvascular disease, certainly in diabetic retinopathy, we see it occur in its real manifestations in the diabetes blood sugar level. With neuropathy, it’s a little bit less clear. It may occur at much lower levels of glycemia.

With macrovascular disease, there seems to be a continuum of risk from levels, such as fasting glucose below 100 mg per deciliter (still above the population average), going all the way up through the diabetes spectrum. So there has been this controversy of what the target is, and we still don’t have an answer. But, we have to be aware that starting very early in treating glycemia and treating diabetes will track in many ways with improved outcomes.

Dennis P. Scanlon, PhD: The scientific evidence for this disease has really advanced quite rapidly, particularly probably in the past 10 or 15 years or so. Results from the SPRINT trial, for example, suggest that controlling blood pressure more aggressively may be better for high-risk patients, although it’s unclear of the implications for diabetics. And, new ADA (American Diabetes Association) guidelines reinforce strict glycemic control for seniors.

Not only is there evidence, but some of the evidence is targeted to specific patient populations or segments of the diabetic population. How are clinicians in the world dealing with this scientific evidence as it comes out? Are we getting it from bench to practice? Do we know how to get it to practice?

Robert Gabbay, MD, PhD, FACP: I think one of the things that makes it more challenging, and I’m sure we’ll get into this, is that there’s controversy. One study suggests one thing in one population. Another study looks at a somewhat different population with maybe less power, to see differences, and doesn’t see differences.

There’s a need to interpret all of that information, and particularly, as we’re saying that most diabetes is cared for by primary care, the patients have diabetes, asthma, congestive heart failure, and many diseases. It’s complex. It’s not simple to say, “Just do this.” I think really the best guidelines are more nuanced, and need to be, as we individualize our care.

John A. Johnson, MD, MBA: One thing that is common in both, whether it’s the ADA or the AACE (the American Association of Clinical Endocrinologists), the goal is to get the HbA1c as low as possible without causing hypoglycemia. Whether that’s 7 or that’s 6.5, we have seen tangible benefits from a clinical outcomes perspective to having a lower HbA1c. That’s unanimous.

Robert Gabbay, MD, PhD, FACP: Absolutely.

John A. Johnson, MD, MBA: And so however we can empower the clinician and the patient to get there, that’s really our charge.

Dennis P. Scanlon, PhD: What about in the area of hypertension? Zachary mentioned the SPRINT trial. What are your thoughts on that? I know there’s some suggestions about whether guidelines should be updated or changed based on the patient population that was included in that trial. So there is some question about the implications for diabetes.

Zachary T. Bloomgarden, MD, MACE: The SPRINT trial is just the latest in a succession of trials of blood pressure goals for people with diabetes. In the SPRINT trial, nondiabetic persons [were included]. We go all the way back to the United Kingdom prospective diabetes trial sub-study of hypertension, where the comparison was 155 versus 145 systolic. That showed tremendous benefit in terms of reduction of heart failure, cardiovascular outcomes, of retinopathy, essentially across the board.

Now we’ve moved past that. In 2008, we had the report of a very large important trial, the ACCORD blood pressure sub-study, which compared a blood pressure of around 130 systolic versus a blood pressure of around 120 systolic in individuals with diabetes who had high cardiovascular risk. Most of them had either a lot of risk factors or already had disease—most of them with a decade of diabetes. The trial was a surprise, because it didn’t clearly show benefit of the systolic of 120 as opposed to 130. That led to a lot of discussion. Actually, the American Diabetes Association took a step that one might say is backward and said, “Well, maybe 140 is okay for a goal.”

Michael Gardner, MD: The strongest evidence being there for 140, right?

Zachary T. Bloomgarden, MD, MACE: The reality is that if you look at specific outcomes in ACCORD, stroke was reduced much more at 120 than 130. In a population where stroke was more common, ACCORD blood pressure would suggest that better goals are needed. On the other hand, renal function worsened at the lower blood pressure—and so that’s a different population. Different targets may be appropriate there.

Now we come to SPRINT. In SPRINT, the control population was at 140 and, lo and behold, in this study of people who did not have diabetes, it looks like, again, lower is better. There’s a meta-analysis that just came out among people with diabetes showing very similar evidence that systolic blood pressures lower than 130 may be better.

So, my understanding of all of this, as a clinician, is that we need to truly individualize blood pressure treatment goals as we do with glycemic goals, lipid goals, etc, in treating the individual very carefully by watching their renal function and being cognizant of what their risk is. If it’s someone who’s had a stroke, or someone with a strong positive family history, then we might aim lower. If we treat someone and we notice their creatinine rising, we might have to back off. It is nuance, and unfortunately, as Einstein said, [we need to] “keep everything as simple as possible, but not too simple.”