Current ADA guidelines recommend an individualized, stepwise approach to treatment with sequential addition of single oral antihyperglycemic agents for patients who do not achieve their glycemic goal in 3 months [27]. Although T2D may progress at different rates in different patients, T2D does generally progress over time [28], and the ADA and American Association of Clinical Endocrinologists treatment guidelines recommend initial dual add-on therapy for individuals with higher A1C, which is suggestive of more advanced disease [27,29]. For individuals requiring initial combination therapy, guidelines note that antihyperglycemic agents that have a low risk of hypoglycemia and low potential for weight gain should be preferentially selected [29]. Attainment of A1C ≤ 7%, the guideline recommendation considered appropriate for many patients, is associated with reductions in microvascular disease and, if attained soon after diagnosis of diabetes, studies have shown reductions in macrovascular disease with long-term follow-up [27,30,31]. However, it may be challenging to achieve A1C < 7% with the addition of single oral antihyperglycemic agents, especially in patients with higher A1C [32]. Less stringent A1C goals (eg, A1C < 8%) may be appropriate in individuals with a long duration of diabetes that is difficult to control, history of severe hypoglycemia, limited life expectancy, numerous comorbidities, and extensive complications or comorbidities, especially cardiovascular disease [27]. Given the shift toward individualized treatment plans with patient-specific treatment goals, it is valuable to understand how different treatment strategies effect attainment of guideline-recommended less stringent and more stringent glycemic targets that may be appropriate for certain patients.
In addition to quality measures that assess glucose lowering with pharmacotherapy, it is important to consider measures that assess other aspects of diabetes care. For example, quality measures related to hypoglycemia and hyperglycemia may help avoid potentially adverse glucose levels, and quality measures related to weight may provide insight on treatment and lifestyle efforts directed at weight loss and management. NQF-endorsed measures of hypoglycemia and hyperglycemia are currently moving through annual review and are paired measures, intended to be interpreted with respect to one another to ensure balanced outcomes [33,34]. This underscores the value of efficacious antihyperglycemic agents with low intrinsic potential for hypoglycemia. Although this analysis did not include quality measures related to hypoglycemia or weight, future studies evaluating these aspects of diabetes care will likely further contribute to a more comprehensive and holistic treatment approach.
In addition to assessing a broad range of quality measures, an important aspect of care to consider is patient affordability. Affordability for an individual patient will depend on access in the patient’s individual plan, the financial resources of the patient, and the potential for medical cost offsets from improved control of the patient’s disease. For example, fixed-dose combination products are associated with increased patient adherence and may increase pharmacy costs but decrease medical costs [35].
Limitations of this study include the post hoc design and that quality measure attainment was assessed over a shorter duration of time (24 weeks) than is commonly assessed in the real-world/community setting (~12 months).
Dual add-on therapy with oral antihyperglycemic agents that have complementary mechanisms of action should lead to enhanced reductions in A1C. The results reported here and from the primary study, in which saxagliptin and dapagliflozin added to metformin significantly reduced mean A1C from baseline to week 24 compared with single add-on saxagliptin or dapagliflozin [15], showed that greater reductions in A1C were attained with the coadministration of saxagliptin and dapagliflozin. The glucuretic effect of SGLT-2 inhibitors has been associated with increased plasma glucagon concentrations and increased endogenous glucose production, which may impair the full glucose-lowering potential of SGLT-2 inhibitors [36,37]. Administering saxagliptin with dapagliflozin as dual therapy was shown to blunt the rise in plasma glucagon caused by dapagliflozin [38], and this may have contributed to the greater glucose control achieved with dual add-on of these 2 antihyperglycemic drugs [15].