Table 1

Characteristics of 252,467 patients with diabetes by pioglitazone use: KPNC Diabetes Registry, 1997–2005

Ever user of pioglitazoneNever user of pioglitazone§
n26,364226,103
Total person-years in each age-group*
 40–497,733 (11.6%)134,484 (14.4%)
 50–5919,588 (29.3%)242,792 (26.0%)
 60–6921,029 (31.4%)253,584 (27.2%)
 ≥7018,533 (27.7%)302,526 (32.4%)
Female12,438 (47.2%)105,165 (46.5%)
Income
 Low14,100 (53.5%)121,581 (53.8%)
 High11,821 (44.8%)99,038 (43.8%)
 Missing443 (1.7%)5,484 (2.4%)
Race/ethnicity
 Non-Hispanic white12,628 (47.9%)106,267 (47.0%))
 African American2,286 (8.7%)21,086 (9.3%)
 Asian or Pacific Islander2,895 (11.0%)26,018 (11.5%)
 Hispanic2,717 (10.3%)19,304 (8.5%)
 Other1,479 (5.6%)11,660 (5.1%)
 Missing4,359 (16.5%)41,768 (18.5%)
Current smoking
 Yes5,105 (19.4%)41,197 (18.2%)
 No21,259 (80.6%)178,245 (78.8%)
 Missing0 (0.0%)6,661 (2.9%)
Renal function
 Normal creatinine19,750 (74.9%)178,677 (79.0%)
 Elevated creatinine**1,262 (4.8%)19,109 (8.5%)
 Missing5,352 (20.3%)28,317 (12.5%)
Congestive heart failure970 (3.7%)14,542 (6.4%)
Baseline HbA1c (%)
 <7.0%4,184 (15.9%)72,576 (32.1%)
 7.0–7.9%4,384 (16.6%)39,661 (17.5%)
 8.0–8.9%3,273 (12.4%)20,597 (9.1%)
 9.0–9.9%2,568 (9.7%)14,068 (6.2%)
 ≥10.0%5,928 (22.5%)34,108 (15.1%)
 Missing6,027 (22.9%)45,093 (19.9%)
Time since diabetes diagnosis (years)
 0–413,793 (52.3%)154,915 (68.5%)
 5–92,684 (10.2%)10,980 (4.9%)
 ≥102,796 (10.6%)19,311 (8.5%)
 Missing7,091 (26.9%)40,897 (18.1%)
Other TZDs2,772 (10.5%)2,803 (1.2%)
Metformin20,418 (77.5%)89,384 (39.5%)
Sulfonylureas21,550 (81.7%)111,725 (49.4%)
Other oral agents1,217 (4.6%)2,003 (0.9%)
Insulin9,880 (37.5%)41,631 (18.4%)
Estrogen only***2,478 (19.9%)14,492 (13.8%)
Estrogen plus progestin ***1,682 (13.5%)7,729 (7.4%)
Pioglitazone use during follow-up
Time since starting pioglitazone (months)
 Median (range)28.8 months (2.4–74.4)N/A
 <12 months6,698 (25.4%)N/A
 12–23 months4,938 (18.7%)N/A
 24–35 months4,391 (16.7%)N/A
 36–47 months3,992 (15.1%)N/A
 48+ months6,345 (24.1%)N/A
Duration of therapy (months)
 Median (range)19.2 months (2.4–74.4)N/A
 <12 months8,898 (33.8%)N/A
 12–23 months6,782 (25.7%)N/A
 24–35 months4,439 (16.8%)N/A
 36+ months6,245 (23.7%)N/A
Cumulative dose (mg)
 Median (range)15,000 mg (450–90,000)N/A
 1–9,000 mg9,167 (34.8%)N/A
 9,001–25,000 mg8,899 (33.7%)N/A
 >25,000 mg8,298 (31.5%)N/A
  • Data are n (%) unless otherwise indicated. N/A, not applicable.

  • †Filled at least two prescriptions within a 6-month period.

  • *With pioglitazone use treated as a time-varying variable.

  • **Creatinine ≥1.4 for women and ≥1.5 for men.

  • ‡Low income defined as median household income in census block below the cohort average ($59,000).

  • ***Data from 12,438 women treated with pioglitazone and 105,165 women never treated with pioglitazone.

  • §All comparisons between ever user of pioglitazone and never user of pioglitazone have P values <0.05 except use of estrogen only (P = 0.06).