Considerations for Making and Achieving Individualized A1c Goals

A1c goals are not a one-size-fits-all; here are some factors you might want to think about to help patients meet their individualized target A1c goals. 

For patients with diabetes, arguably the most important predictor of disease prognosis is A1c. Once diagnosed with diabetes, patients will be assigned an A1c target goal. The 2021 ADA Standards of Care guideline for diabetes mellitus recommends an A1c of <7% for most people. In reality, various factors come into play when determining A1c targets, such as patient factors (adherence, prognosis, etc.), healthcare-related factors (i.e., cost, lack of resources/time to provide adequate care), and more. Another consideration is the likelihood of the patient to achieve the established A1c target. A study by Pantalone et al. noticed that only 23.7% of 6,973 patients with uncontrolled type 2 diabetes (T2DM) could achieve an A1c goal of <8%. Recently, a secondary analysis of the MOSA1c study identified patient/provider/healthcare-related factors that can predict the likelihood of having an individualized A1c goal >7% and the odds of the patient achieving it.  

Data from this secondary analysis came from the MOSA1c study, a multinational observational cohort that looked at predictors associated with insulin progression among patients with T2DM. Patients included were people with T2DM aged 18 years and up, on insulin for ≥ three months, and presented in the ordinary course of care. Those taking more intensive insulin-based regimens (i.e., basal-bolus insulin) were excluded. Furthermore, patients completed questionnaires like the ENSEMBLE MDS, Interpersonal Processes of Care (IPC), Diabetes Distress Scale, and the Brief Diabetes Knowledge Test at baseline and after two years to gather insight about their knowledge and perceptions of diabetes and care. Physicians were also surveyed at baseline about information such as treatment beliefs/preferences and more. At the beginning of the study, the physician would choose an A1c goal for the patient. Investigators recorded the patients’ A1c, insulin type, dose, frequency of injections, and the number of hypoglycemic events at each follow-up visit. Data collection occurred every six months (±3 months) from baseline over two years. For statistical analysis, the authors compared patient/provider/healthcare-related factors between those who were able to or unable to achieve their A1c goal using Wilcoxon Rank-Sum and Chi-Square tests. They identified baseline factors that led to an A1c goal >7% and factors that may have led to achieving these goals via a logistic regression model. 

After two years, 225 of 1194 patients (18.8%) achieved their A1c target. On average, patients at baseline had an A1c of 8.4%, and the mean target level was 6.8%. Based on baseline characteristics, the authors noticed that patients with a shorter duration since diagnosis and patients categorized as White were more likely to reach their goal (p<0.01 for both). Furthermore, patients with a higher mean A1c target (7.1% vs. 6.7%, respectively) were more likely to reach their goal, especially if their baseline A1c was close to it from the beginning (p <0.001). According to the IPC survey, patients who achieved their goal were more likely to rate a less positive relationship with their physician regarding discrimination or the amount of time spent on education and patient-based care. However, this was deemed not clinically significant as they scored their relationships overall positively. Regarding treatment, 67.1% of patients had to have their treatment intensified by 18 months, with those who did not reach their target at the two-year follow-up more likely to need additional therapy (70.1% vs. 54.2%; p < 0.001). Predictors for higher individualized A1c goals are as follows: Asian, less than high school education, long duration of diabetes (>11.3 years), microvascular disease at baseline, A1c >8% at baseline (OR 6.06 [CI 3.97 to 9.26]), and high insulin doses (>28 units/day). Finally, predictors of reaching A1c targets were minor differences between baseline and goal A1c, White, shorter duration of diabetes, a higher rating of discrimination from the physician, and no treatment intensification from baseline to month 18.

Based on the results, it is apparent that various factors can prevent a patient from reaching their A1c target. High A1c levels at baseline and substantial differences between baseline A1c and target seem to be the two strongest predictors of patients being assigned a higher A1c target and their ability to reach it, respectively. While this study did not determine causation, a holistic approach remains the best method of providing patient-based care. With many patients with diabetes unable to reach their A1c target, recognizing barriers to care from multiple viewpoints is the key to optimizing therapy and preventing complications in the future. 

Practice Pearls:

• Patients with high A1c levels at baseline (>8%) were more likely to be assigned an A1c goal >7%.
• Patients are more likely to achieve an A1c goal closer to their A1c level at baseline.
• A holistic approach to therapy may ensure glycemic goals of treatment are met. 

Caballero, A. E et al. “Individualized HbA1c target selection and achievement in the Multinational Observational Study Assessing Insulin Use (MOSA1c) type 2 diabetes study”. Journal of Diabetes and its Complications, July 30, 2021. doi:10.1016/j.jdiacomp.2021.108011

American Diabetes Association. “6. Glycemic Targets: Standards of Medical Care in Diabetes-2021.” Diabetes care vol. 44, Suppl 1, Jan 2021: S73-S84. doi:10.2337/dc21-S006

Pantalone, Kevin M et al. “The Probability of A1C Goal Attainment in Patients With Uncontrolled Type 2 Diabetes in a Large Integrated Delivery System: A Prediction Model.” Diabetes care vol. 43,8 (2020): 1910-1919. doi:10.2337/dc19-0968

Polinski, Jennifer M et al. “Rationale and design of the multinational observational study are assessing insulin use: the MOSAIc study.” BMC endocrine disorders vol. 12 20. September 21. 2012. doi:10.1186/1472-6823-12-20

Andy Dao, PharmD Candidate, University of South Florida Taneja College of Pharmacy

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