Table 2 Baseline characteristics for patients receiving antidiabetic monotherapy. Characteristics include demographic characteristics; insurance coverage; period of first hospital admission; comorbidities; medical care received; and disease severity. In order to achieve balance between the cohorts in characteristic distributions, propensity scores were estimated and used as a covariate in the Cox proportional hazard regression following a statistical check to see whether balance was achieved

Total

8,705,468

3,217,089

5,488,379

Mean Age (95 % CI)

63.4 (62.5–64.4)

68.3 (67.0–69.7)

60.5 (59.3–61.7)

<0.0001

0.951

Male

3,738,700 (42.9)

1,514,251 (47.1)

2,224,449 (40.5)

0.093

0.985

Race

 White

6,859,909 (78.8)

2,525,415 (78.5)

4,346,796 (79.2)

 African American

1,305,820 (15.0)

466,478 (14.5)

856,187 (15.6)

0.784

0.912

 Other

539,739 (6.2)

225,196 (7.0)

285,396 (5.2)

Region

 Northeast

1,647,688 (18.9)

465,284 (14.5)

1,182,404 (21.5)

 Midwest

2,007,585 (23.1)

777,258 (24.2)

1,230,327 (22.4)

0.115

0.994

 South

3,290,396 (37.8)

1,278,818 (39.8)

2,011,578 (36.7)

 West

1,534,591 (17.6)

526,591 (16.4)

1,008,000 (18.4)

Married

4,530,506 (52.0)

1,578,073 (49.1)

2,952,432 (53.8)

0.193

0.992

Insurance status

 Public

3,410,507 (39.2)

1,455,344 (45.2)

1,955,164 (35.6)

 Private

4,442,060 (51.0)

1,457,269 (45.3)

2,984,792 (54.4)

0.0881

0.998

 Other

223,194 (2.6)

136,278 (4.2)

86,916 (1.6)

 Uninsured

629,707 (7.2)

168,199 (5.2)

461,508 (8.4)

Period of first hospital admission

 1999–2003

1,796,930 (20.6)

1,012,088 (31.5)

784,842 (14.3)

 2004–2007

3,932,720 (45.2)

1,475,349 (45.9)

2,457,371 (44.8)

<0.0001

0.937

 2008–2010

2,975,819 (34.2)

729,652 (22.7)

2,246,166 (40.9)

Cardiovascular disease

5,272,543 (60.6)

1,695,922 (52.7)

3,576,621 (65.2)

0.0017

0.966

Renal disease

823,544 (9.5)

354,703 (11.0)

468,840 (8.52)

0.298

0.979

Eye disease

1,454,104 (16.7)

547,914 (17.7)

886,190 (16.2)

0.624

0.995

Mean number of HbA1c tests (95 % CI)

3.5 (2.4–4.7)

3.1 (1.4–4.92)

3.8 (2.3–5.2)

0.602

0.443

Perceived health status

 Excellent/Very good

1,782,916 (20.5)

616,432 (19.2)

1,166,485 (21.3)

 Good

2,674,290 (30.7)

792,801 (24.6)

1,881,489 (34.3)

0.012

0.973

 Fair/Poor

4,161,730 (47.8)

1,767,732 (55.0)

2,393,999 (43.6)

Perceived mental health status

 Excellent/Very good

3,830,005 (44.0)

1,219,758 (37.9)

2,610,246(48.2)

 Good

2,678,886 (30.8)

998,646 (31.0)

1,680,241 (30.6)

0.017

0.919

 Fair/Poor

2,110,045 (24.2)

958,560 (29.8)

1,150,485 (21.0)

Physical limitations

4,119,188 (47.3)

1,634,470 (50.8)

2,484,718 (45.3)

0.153

0.991

Difficulty in getting care

4,541,484 (52.2)

1,554,111 (48.3)

2,987,374 (54.4)

0.107

0.989