Impact of Age ≥75 Years on Glycemic Outcomes After Intermittently Scanned Continuous Glucose Monitoring (isCGM)...

To assess whether adults aged ≥75 years with type 2 diabetes (T2D) treated with multiple daily insulin injections achieve glycemic improvements comparable to younger adults after initiation of intermittently scanned continuous glucose monitoring (isCGM) within a universal-coverage health system.

Post hoc subanalysis of a retrospective multicenter cohort from 3 hospitals. Adults with T2D on multiple daily insulin injections who initiated isCGM had glycated hemoglobin A1c (HbA1c) measured ≤1 month preinitiation and ≥3 months post-initiation. Mixed-effects linear regression modeled HbA1c with fixed effects for time (post vs pre), age group (≥75 vs <75 years), and their interaction, plus a random intercept. Models were adjusted for sex, body mass index, smoking, other antidiabetic agents, nephropathy, and area-level income; candidate confounders were screened using a >10% change-in-estimate criterion.

Of 402 participants (mean age 67.3 ± 10.4 years; 22.9% ≥ 75), paired HbA1c was available for 384. Overall HbA1c fell from 8.5 ± 1.5% to 7.7 ± 1.1% (P < .001). Reductions occurred in both age groups: <75 years, 8.6 ± 1.5% to 7.8 ± 1.1% (Δ-0.81%); ≥75 years, 8.2 ± 1.4% to 7.6 ± 0.9% (Δ-0.64%); both P < .001. In adjusted models, time predicted lower HbA1c (β -0.843; 95% CI -1.016 to -0.669; P < .001). Neither age ≥75 (β -0.388; 95% CI -0.988 to 0.213; P = .206) nor the age×time interaction (β 0.164; 95% CI -0.199 to 0.527; P = .376) was significant, indicating similar benefit.

In a publicly funded system, isCGM use was associated with clinically meaningful HbA1c reductions in T2D patients on multiple daily insulin injections, with no attenuation among adults ≥75 years. Chronological age should not restrict isCGM prescription; policies should address ageism and ensure equitable access for older adults.