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.