Table 1.
Characteristics of 252,467 patients with diabetes by pioglitazone use: KPNC Diabetes Registry, 1997–2005
| Ever user of pioglitazone† | Never user of pioglitazone§ | |
|---|---|---|
| n | 26,364 | 226,103 |
| Total person-years in each age-group* | ||
| 40–49 | 7,733 (11.6%) | 134,484 (14.4%) |
| 50–59 | 19,588 (29.3%) | 242,792 (26.0%) |
| 60–69 | 21,029 (31.4%) | 253,584 (27.2%) |
| ≥70 | 18,533 (27.7%) | 302,526 (32.4%) |
| Female | 12,438 (47.2%) | 105,165 (46.5%) |
| Income | ||
| Low‡ | 14,100 (53.5%) | 121,581 (53.8%) |
| High | 11,821 (44.8%) | 99,038 (43.8%) |
| Missing | 443 (1.7%) | 5,484 (2.4%) |
| Race/ethnicity | ||
| Non-Hispanic white | 12,628 (47.9%) | 106,267 (47.0%)) |
| African American | 2,286 (8.7%) | 21,086 (9.3%) |
| Asian or Pacific Islander | 2,895 (11.0%) | 26,018 (11.5%) |
| Hispanic | 2,717 (10.3%) | 19,304 (8.5%) |
| Other | 1,479 (5.6%) | 11,660 (5.1%) |
| Missing | 4,359 (16.5%) | 41,768 (18.5%) |
| Current smoking | ||
| Yes | 5,105 (19.4%) | 41,197 (18.2%) |
| No | 21,259 (80.6%) | 178,245 (78.8%) |
| Missing | 0 (0.0%) | 6,661 (2.9%) |
| Renal function | ||
| Normal creatinine | 19,750 (74.9%) | 178,677 (79.0%) |
| Elevated creatinine** | 1,262 (4.8%) | 19,109 (8.5%) |
| Missing | 5,352 (20.3%) | 28,317 (12.5%) |
| Congestive heart failure | 970 (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%) |
| Missing | 6,027 (22.9%) | 45,093 (19.9%) |
| Time since diabetes diagnosis (years) | ||
| 0–4 | 13,793 (52.3%) | 154,915 (68.5%) |
| 5–9 | 2,684 (10.2%) | 10,980 (4.9%) |
| ≥10 | 2,796 (10.6%) | 19,311 (8.5%) |
| Missing | 7,091 (26.9%) | 40,897 (18.1%) |
| Other TZDs† | 2,772 (10.5%) | 2,803 (1.2%) |
| Metformin† | 20,418 (77.5%) | 89,384 (39.5%) |
| Sulfonylureas† | 21,550 (81.7%) | 111,725 (49.4%) |
| Other oral agents† | 1,217 (4.6%) | 2,003 (0.9%) |
| Insulin† | 9,880 (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 months | 6,698 (25.4%) | N/A |
| 12–23 months | 4,938 (18.7%) | N/A |
| 24–35 months | 4,391 (16.7%) | N/A |
| 36–47 months | 3,992 (15.1%) | N/A |
| 48+ months | 6,345 (24.1%) | N/A |
| Duration of therapy (months) | ||
| Median (range) | 19.2 months (2.4–74.4) | N/A |
| <12 months | 8,898 (33.8%) | N/A |
| 12–23 months | 6,782 (25.7%) | N/A |
| 24–35 months | 4,439 (16.8%) | N/A |
| 36+ months | 6,245 (23.7%) | N/A |
| Cumulative dose (mg) | ||
| Median (range) | 15,000 mg (450–90,000) | N/A |
| 1–9,000 mg | 9,167 (34.8%) | N/A |
| 9,001–25,000 mg | 8,899 (33.7%) | N/A |
| >25,000 mg | 8,298 (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).