Baseline demographic and clinical characteristics of study cohorts
| Demographic and clinical characteristics | Cohort 1 No medication | Cohort 2 NIAD initiators | Cohort 3 Basal insulin initiators | Cohort 4 Prandial/mixed insulin initiators |
|---|---|---|---|---|
| Number of patients | 597 664 | 342 511 | 99 578 | 62 876 |
| Age (mean (SD) (years)) | 59.1 (13.9) | 56.2 (12.1) | 57.8 (12.2) | 59.1 (13.2) |
| Gender (%) | ||||
| Male | 49.0 | 54.3 | 54.8 | 52.7 |
| Female | 51.0 | 45.7 | 45.2 | 47.3 |
| Geographic region (%) | ||||
| North-East | 16.5 | 12.6 | 11.0 | 10.5 |
| North Central | 29.9 | 27.4 | 29.0 | 29.4 |
| South | 36.2 | 42.1 | 39.7 | 40.7 |
| West | 16.9 | 17.3 | 19.7 | 18.8 |
| Unknown | 0.6 | 0.6 | 0.6 | 0.6 |
| Insurance plan type (%) | ||||
| Comprehensive | 19.0 | 12.8 | 15.4 | 17.7 |
| EPO | 0.9 | 1.0 | 0.9 | 0.8 |
| HMO | 15.6 | 17.3 | 20.0 | 19.1 |
| POS (includes plans w/o capitation) | 7.7 | 9.0 | 9.1 | 8.7 |
| PPO | 50.0 | 51.7 | 47.2 | 46.6 |
| Unknown/missing | 4.0 | 4.4 | 3.7 | 3.8 |
| Other (basic/major medical, CHDP, HDHP) | 2.8 | 3.7 | 3.6 | 3.4 |
| Deyo-Charlson comorbidity index (mean (SD)) | 1.8 (1.5) | 1.6 (1.4) | 2.3 (1.9) | 2.5 (2.1) |
| Microvascular and macrovascular complications (%) | ||||
| Diabetic neuropathy | 6.7 | 7.4 | 14.8 | 16.8 |
| Renal disease | 9.8 | 7.4 | 16.0 | 19.7 |
| Ischemic heart disease | 16.3 | 12.9 | 20.2 | 23.4 |
| Disorders of lipid metabolism | 42.3 | 40.9 | 40.1 | 38.7 |
| Hypertension | 54.7 | 52.2 | 56.3 | 58.5 |
CHDP, Child Health and Disability Prevention; EPO, exclusive provider organization; HDHP, high-deductible health plan; HMO, house in multiple occupation; NIAD, non-insulin antidiabetic drug; POS, point of service; PPO, preferred provider organization.