Background: Despite multiple therapeutic options for people with T2DM, 48% of people do not achieve Hemoglobin A1c (HbA1c) goal. GLP-1 receptor agonists may be beneficial to patients with T2DM who are on large insulin doses and are obese. GLP-1 receptor agonists are often used with oral medications and/or basal insulin. GLP-1 agents are not typically used with those on prandial insulin.

Clinical cases: We present 2 cases of uncontrolled T2DM whose HbA1c significantly improved on GLP-1 and daily mixed insulin. Patient A is a 62 y/o M with T2DM for 15 years, weight of 112 kg (BMI 35), HbA1c of 10.2% (diabetes ref range > 6.4%), on 65u insulin detemir BID (total daily insulin 0.9 u/kg). HbA1c decreased to 7.1% by 2 month on dulaglutide 1.5mg weekly, insulin Humalog mix 75/25 45u BID (total daily insulin 0.8u/kg) and metformin ER 1000mg BID. HbA1c at 12 months was 6.1% and weight 112kg (BMI 35). Patient B is a 61 y/o F with T2DM for 17 years, weight of 92 kg (BMI 35), HbA1c of 10.9%, on 50u insulin glargine BID and not adherent to her insulin lispro (total daily insulin 1.6 u/kg). HbA1c decreased to 6.3% at 2 month on dulaglutide 1.5 mg weekly, insulin Novolog mix 70/30 30u BID (total daily insulin 0.7u/kg) and metformin ER 500mg BID. HbA1c at 12 months was 6.6%, and weight decreased to 87kg (BMI 34).

Discussion: Our patients were on metformin and high dose insulin without HbA1c improvement. Their regimens were changed to once weekly GLP-1 agonists with mixed insulin which showed improved and sustained glycemic control after one year without major hypoglycemic events.

Conclusion: These cases highlight the potential utility of GLP-1 receptor agonist therapy in combination with mixed insulin for patients with uncontrolled T2DM on high dose insulin. We hypothesize that increased compliance may be an import factor but further research needs to be completed.


S. Fazeli: None. N. Ehrhardt: None.

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