OBJECTIVES: This study compared older (≥ 65 yrs) and younger patients with newly diagnosed T2DM, and evaluated factors associated with oral antihyperglycemic agent (OAHA) initiation. METHODS: This retrospective cohort study used U.S. General Electric (GE) Centricity electronic medical record database. Patients aged ≥30 yrs with newly-diagnosed T2DM (January-2003 to December-2005) were included. There was no diabetes diagnosis or treatment within 2 years prior to the first recorded T2DM diagnosis. Medical records 1 year prior to (baseline) and 2 years after (follow-up) diagnosis were extracted. OAHA initiation was estimated based on the first OAHA prescription during follow-up. Multivariable Cox proportional hazards regression model was fitted. Untreated patients were censored at complete 2 years follow-up. RESULTS: Among 10,760 newly diagnosed T2DM patients, 55% were female. Mean age at T2DM diagnosis was 61.3(±12.5), with 4,617 (43%) ≥65 yrs. At baseline, older relative to younger patients had lower HbA1c (6.7% vs. 7.2%, with only 38% vs. 32% attaining HbA1c <7% goal), lower fasting blood glucose (117.9 vs. 132.8 mg/dL) and lower BMI (30.6 vs. 35.2), higher rates of acute myocardial infarction (MI) (2.1% vs. 0.9%), heart failure (5.1% vs. 1.8%), stroke (3.1% vs. 0.8%), and renal disease (17.5% vs. 6.2%), and more co-medications (all p-values <0.05). Within 2 years after T2DM diagnosis, 56% older and 40.5% younger patients (P<0.001) had not received OAHA. Older patients were less likely to be treated than younger patients (adjusted hazard ratio 0.84, p<0.001). Additionally, patients with baseline MI or renal disease were less likely to be treated (p<0.05). Higher BMI or HbA1c at baseline, and heart failure, initiating antihypertensive or lipid lowering drugs after T2DM diagnosis were factors associated with increased likelihood of OAHA treatment (p<0.05).  CONCLUSIONS: Older patients with newly diagnosed T2DM had milder hyperglycemia but more comorbidities, and experienced more delayed OAHA therapy than younger patients.