Table 1.
Patient Characteristics of Older Diabetic Patients Taking Glyburide or Glipizide for Diabetes and Their Association With Being Prescribed Co-trimoxazole in a 5% National Sample of Medicare Recipients in 2008–2010
| Patient Characteristics | N | % (95% CI) Prescribed Co-trimoxazole | OR (95% CI) |
|---|---|---|---|
| All | 37,086 | 16.6 (16.2–17.0)* | |
| Age (y) | |||
| 66–74 | 17,378 | 16.1 (15.6–16.6) | ref |
| 75–84 | 14,771 | 16.9 (16.3–17.5) | 1.05 (0.99–1.12) |
| 85+ | 4,937 | 19.4 (18.3–20.5) | 1.27 (1.16–1.38) |
| Sex | |||
| Male | 14,133 | 13.5 (12.9–14.1) | Ref |
| Female | 22,953 | 19.0 (18.5–19.5) | 1.44 (1.35–1.53) |
| Race | |||
| Non-Hispanic white | 26,973 | 17.5 (17.0–18.0) | Ref |
| Non-Hispanic black | 4,024 | 15.5 (14.4–16.6) | 0.76 (0.69–0.83) |
| Hispanic | 3,893 | 16.2 (15.0–17.4) | 0.82 (0.74–0.90) |
| Other | 2,158 | 13.2 (11.8–14.6) | 0.72 (0.63–0.83) |
| Medicaid eligibility | |||
| Yes | 13,533 | 19.2 (18.5–19.9) | 1.21 (1.14–1.30) |
| No | 23,553 | 15.5 (15.0–16.0) | Ref |
| Number of comorbidities | |||
| 0 | 3,668 | 14.7 (13.6–15.8) | Ref |
| 1 | 12,126 | 14.5 (13.9–15.1) | 0.93 (0.83–1.03) |
| 2 | 8,558 | 16.5 (15.7–17.3) | 0.96 (0.86–1.08) |
| 3+ | 12,734 | 20.0 (19.3–20.7) | 0.98 (0.88–1.10) |
| Number of hospitalizations in 2007 | |||
| 1+ | 27,072 | 15.6 (15.2–16.0) | 1.16 (1.07–1.26) |
| 0 | 10,014 | 20.4 (19.6–21.2) | Ref |
| Having a primary care provider | |||
| No | 14,982 | 17.7 (17.1–18.3) | Ref |
| Yes | 22,104 | 16.3 (15.8–16.8) | 0.88 (0.83–0.93) |
| Average number of different oral medications† | |||
| 1–4 | 15,785 | 12.6 (12.1–13.1) | Ref |
| 5–9 | 18,875 | 19.3 (18.7–19.9) | 1.44 (1.35–1.53) |
| 10+ | 2,426 | 25.9 (24.2–27.6) | 1.86 (1.66–2.07) |
| Number of different prescribers‡ | |||
| 1–3 | 10,254 | 12.3 (11.7–12.9) | Ref |
| 4–7 | 14,679 | 15.8 (15.2–16.4) | 1.34 (1.25–1.45) |
| 8+ | 12,153 | 22.1 (21.4–22.8) | 1.93 (1.79–2.08) |
Notes: CI = confidence interval; OR = odds ratio.
*The coadministration rates of co-trimoxazole were 16.3% (95% CI: 15.7–16.8%) for glyburide users and 17.1% (95% CI: 16.6–17.6%) for glipizide users.
†The number of different oral medications on the first day of each month during 2008–2010 was calculated using Medicare Part D claims. The monthly totals were then converted to a yearly average as a measure of polypharmacy.
‡The Medicare Part D claims in 2008–2010 were used to extract the number of different prescribers.