Objective: To evaluate glycemic outcomes in the Wireless Innovation for Seniors with Diabetes Mellitus (WISDM) randomized clinical trial (RCT) participants during an observational extension phase. Research Design and Methods: WISDM RCT was a 26-week RCT comparing continuous glucose monitoring (CGM) with blood glucose monitoring (BGM) in 203 adults aged 鈮� 60 years with type 1 diabetes. Of the 198 participants who completed the RCT, 100 (98%) CGM group participants continued CGM (CGM-CGM cohort) and 94 (98%) BGM group participants initiated CGM (BGM-CGM cohort) for an additional 26 weeks. Results: CGM was used a median of >90% of the time at 52 weeks in both cohorts. In the CGM-CGM cohort, median time <70鈥塵g/dL decreased from 5.0% at baseline to 2.6% at 26 weeks and remained stable with a median of 2.8% at 52 weeks (P鈥�<鈥�0.001 baseline to 52 weeks). Participants spent more time in range 70-180鈥塵g/dL (TIR) (mean 56% vs. 64%; P鈥�<鈥�0.001) and had lower hemoglobin A1c (HbA1c) (mean 7.6% [59鈥塵mol/mol] vs. 7.4% [57鈥塵mol/mol]; P鈥�=鈥�0.01) from baseline to 52 weeks. In BGM-CGM, from 26 to 52 weeks median time <70鈥塵g/dL decreased from 3.9% to 1.9% (P鈥�<鈥�0.001), TIR increased from 56% to 60% (P鈥�=鈥�0.006) and HbA1c decreased from 7.5% (58鈥塵mol/mol) to 7.3% (57鈥塵mol/mol) (P鈥�=鈥�0.025). In BGM-CGM, a severe hypoglycemic event was reported for nine participants while using BGM during the RCT and for two participants during the extension phase with CGM (P鈥�=鈥�0.02). Conclusions: CGM use reduced hypoglycemia without increasing hyperglycemia in older adults with type 1 diabetes. These data provide further evidence for fully integrating CGM into clinical practice. Clinicaltrials.gov (NCT03240432).