Risk of Infection in Older Adults With Type 2 Diabetes With Relaxed Glycemic Control.

Objective: To compare the risk of hospitalization for infection among patients who achieve intensive versus relaxed glycemic control.

Research Design And Methods: This retrospective cohort study included adults age ≥65 years with type 2 diabetes from an integrated health care delivery system. Negative binomial models were used to estimate incidence rates and relative risk (RR) of hospitalization for infections (respiratory; genitourinary; skin, soft tissue, and bone; and sepsis), comparing two levels of relaxed (hemoglobin A1c [HbA1c] 7% to <8% and 8% to <9%) with intensive (HbA1c 6% to <7%) glycemic control from 1 January 2019 to 1 March 2020.

Results: Among 103,242 older patients (48.5% with HbA1c 6% to <7%, 35.3% with HbA1c 7% to <8%, and 16.1% with HbA1c 8% to <9%), the rate of hospitalization for infections was 51.3 per 1,000 person-years. Compared with HbA1c 6% to <7%, unadjusted risk of hospitalization for infections was significantly elevated among patients with HbA1c 8% to <9% (RR 1.25; 95% CI 1.13, 1.39) but not among patients with HbA1c 7% to <8% (RR 0.99; 95% CI 0.91, 1.08), and the difference became nonsignificant after adjustment. Across categories of infections, the adjusted RR of hospitalization was significantly higher among patients with HbA1c 8% to <9% only for skin, soft tissue, and bone infection (RR 1.33; 95% CI 1.05, 1.69).

Conclusions: Older patients with type 2 diabetes who achieve relaxed glycemic control levels endorsed by clinical guidelines are not at significantly increased risk of hospitalization for most infections, but HbA1c 8% to <9% is associated with an increased risk of hospitalization for skin, soft tissue, and bone infections.