A recently published retrospective study found no worsening of mild to moderate retinopathy in people with Type 2 Diabetes (T2D) who had a rapid improvement in A1C over a short time.
The observational study analyzed 2,300 people with T2D who had mild or moderate, non-proliferative, diabetic retinopathy. The control group consisted of 1,500 people who had what is termed Early Worsening of Diabetic Retinopathy (EWDR) and 1,500 people who did not.
EWDR does not mean “retinopathy that occurs shortly after a diagnosis of T2D.” Instead, it means “early worsening of retinopathy within a short period after a medication is started or adjusted that led to a rapid A1C improvement.” A “rapid reduction” in A1C was defined as a >1.5% decrease over 12 months and a “very rapid” reduction was an A1C that was lowered by >2% over a 6-months.
The data was further divided to search for any differences in the rate of EWDR based on the type of medication(s) people take, how long the person has lived with diabetes, how high the baseline A1C was, or if the person had high blood pressure.
The study had a very positive conclusion:
For those people with T2D who are living with mild or moderate non-proliferative diabetic retinopathy, there was no increased risk for the worsening of retinopathy for people who had a rapid A1C lowering from improved diabetes management.
Older studies have shown that there is an increased risk of rapid worsening of diabetic retinopathy for a few months in people with Type 1 or Type 2 Diabetes who have a rapid drop in A1C over 3-6 months.However, the older studies focused on people with pre-existing severe non-proliferative diabetic retinopathy or those with proliferative retinopathy.
Interestingly, in reviewing summaries of the older studies it was found that, in most cases, after the first few months of worsening of significant retinopathy, the number of increased signs or symptoms of diabetic retinopathy actually improved over several months when improved glucose management remained in place.
When comparing two groups of people with diabetes and significant retinopathy between those with persistently elevated A1Cs of 8.5% or higher to those who had a rapid improvement in A1C and short-term worsening of retinopathy with ongoing well-managed diabetes: over the longer term those with improved diabetes management ended up having less retinopathy than those who maintained higher A1Cs over the long term.
Why this newly published study matters:
While we can’t know if the same findings apply to people with Type 1 Diabetes (T1D), we can look for additional studies moving forward that focus on finding the causes of worsening retinopathy in people with severe retinopathy when glucose levels rapidly improve.
We can also look forward to other retrospective studies that focus on people with T1D with mild to moderate retinopathy to see if the same outcomes are found.
Additionally, there are many people with T2D that are living with mild to moderate retinopathy caused by poorly managed blood glucose and/or high blood pressure.
It is very helpful for family physicians and other health care providers to know that it is safe to improve glucose levels quickly in these individuals. Insulin and/or other medications can be prescribed, or doses can be adjusted, more quickly in people with T2D with mild to moderate retinopathy instead of waiting to adjust slowly over time since this study found there is not a risk for worsening of retinopathy in those individuals.
Tavia Vital BSN, BA, RN, CDCES
Director of Intensive Diabetes Management
Tavia is a Registered Nurse, Certified Diabetes Care and Education Specialist, and Certified Trainer on most makes/models of insulin pumps and continuous glucose monitoring systems. She earned a Bachelor of Science degree in Nursing from Regis University in Denver, Colorado after receiving a Bachelor of Arts degree in Spanish from the University of Iowa.
After working as an inpatient nurse, Tavia shifted her career focus to work as an outpatient nurse and diabetes educator. She worked many years as a diabetes educator in endocrinology, diabetes, and metabolism clinics, a high-risk diabetes and pregnancy clinic, and in family care/primary care provider clinics before joining Integrated Diabetes Services.