Table 2.
Description of elderly (≥65 years) Medicare beneficiaries with type 2 diabetes mellitus who newly added rapid acting insulin to their oral antidiabetic drug regimen. Single versus multiple rapid acting insulin prescription during one-year follow-up. Humana Medicare Advantage Prescription Drug Plan database 2007–2012.
| Single RAI | Multiple RAI | P value | |||
|---|---|---|---|---|---|
| N | Row% | N | Row% | ||
| All (N = 3,734) | 1,400 | 37.5 | 2,334 | 62.5 | |
| Number of OADs | <0.001 | ||||
| 1 OAD | 720 | 41.8 | 1,004 | 58.2 | |
| 2 OADs | 526 | 35.0 | 977 | 65.0 | |
| ≥3 OADs | 154 | 30.4 | 353 | 69.6 | |
|
| |||||
| Demographic characteristics | |||||
|
| |||||
| Gender | |||||
| Female | 693 | 36.5 | 1,206 | 63.5 | |
| Male | 707 | 38.5 | 1,128 | 61.5 | |
| Race | |||||
| White | 1,117 | 37.6 | 1,854 | 62.4 | |
| African American | 203 | 39.3 | 313 | 60.7 | |
| Others | 56 | 35.7 | 101 | 64.3 | |
| Missing | 24 | 26.7 | 66 | 73.3 | |
| Age in years | <0.001 | ||||
| 65–69 years | 436 | 33.6 | 860 | 66.4 | |
| 70–74 years | 411 | 37.7 | 679 | 62.3 | |
| 75–79 years | 331 | 43.3 | 433 | 56.7 | |
| 80+ years | 222 | 38.0 | 362 | 62.0 | |
| Region | <0.001 | ||||
| Midwest | 354 | 31.6 | 768 | 68.4 | |
| South | 920 | 41.3 | 1,307 | 58.7 | |
| Northeast/west/others | 126 | 32.7 | 259 | 67.3 | |
|
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| Health insurance characteristics | |||||
|
| |||||
| Type of plan | |||||
| PFFS | 479 | 36.5 | 832 | 63.5 | |
| HMO | 564 | 39.3 | 871 | 60.7 | |
| PPO/others | 357 | 36.1 | 631 | 63.9 | |
|
| |||||
| Baseline clinical characteristics | |||||
|
| |||||
| Any hypoglycemia | <0.05 | ||||
| Yes | 201 | 42.9 | 268 | 57.1 | |
| No | 1,199 | 36.7 | 2,066 | 63.3 | |
| Severe hypoglycemia | <0.05 | ||||
| Yes | 159 | 43.6 | 206 | 56.4 | |
| No | 1,241 | 36.8 | 2,128 | 63.2 | |
| aDCSI score | |||||
| 0 | 326 | 35.2 | 600 | 64.8 | |
| 1-2 | 424 | 37.2 | 717 | 62.8 | |
| 3-4 | 241 | 40.5 | 354 | 59.5 | |
| 5–13 | 409 | 38.2 | 663 | 61.8 | |
| A1C | <0.001 | ||||
| <8% | 303 | 44.9 | 372 | 55.1 | |
| 8-9% | 71 | 30.3 | 163 | 69.7 | |
| >9% | 82 | 24.7 | 250 | 75.3 | |
| Not available | 944 | 37.9 | 1,549 | 62.1 | |
|
| |||||
| Baseline healthcare utilization | |||||
|
| |||||
| Any inpatient visit | <0.001 | ||||
| Yes | 1,032 | 42.0 | 1,428 | 58.0 | |
| No | 368 | 28.9 | 906 | 71.1 | |
| Any ER visit | <0.001 | ||||
| Yes | 911 | 40.9 | 1,318 | 59.1 | |
| No | 489 | 32.5 | 1,016 | 67.5 | |
|
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| Special conditions for the elderly | |||||
|
| |||||
| Polypharmacy | <0.05 | ||||
| Yes (>14) | 228 | 42.5 | 309 | 57.5 | |
| No (≤14) | 1,172 | 36.7 | 2,025 | 63.3 | |
| Cognitive impairment | <0.01 | ||||
| Yes | 224 | 33.1 | 453 | 66.9 | |
| No | 1,176 | 38.5 | 1,881 | 61.5 | |
| Depression | |||||
| Yes | 211 | 34.7 | 397 | 65.3 | |
| No | 1,189 | 38.0 | 1,937 | 62.0 | |
| Fall | |||||
| Yes | 96 | 40.7 | 140 | 59.3 | |
| No | 1,304 | 37.3 | 2,194 | 62.7 | |
| Urinary incontinence | |||||
| Yes | 63 | 36.4 | 110 | 63.6 | |
| No | 1,337 | 37.5 | 2,224 | 62.5 | |
|
| |||||
| One-year follow-up basal insulin use | |||||
|
| |||||
| Basal insulin | <0.001 | ||||
| Yes | 553 | 28.0 | 1,420 | 72.0 | |
| No | 847 | 48.1 | 914 | 51.9 | |
|
| |||||
| One-year follow-up RAI out-of-pocket cost per RAI prescription | |||||
|
| |||||
| Average cost per RAI prescription | <0.001 | ||||
| $0.0–<$6.3 | 308 | 33.0 | 625 | 67.0 | |
| $6.3–<$36 | 420 | 44.9 | 516 | 55.1 | |
| $36–<$56 | 425 | 45.6 | 507 | 54.4 | |
| ≥$56 | 247 | 26.5 | 686 | 73.5 | |
|
| |||||
| One-year follow-up RAI out-of-pocket cost per 30-day supply | |||||
|
| |||||
| RAI OOP cost per 30-day supply | <0.001 | ||||
| $0.0–<$6.4 | 283 | 30.3 | 651 | 69.7 | |
| $6.4–<$35.5 | 409 | 43.8 | 524 | 56.2 | |
| $35.5–<$47.6 | 403 | 43.1 | 531 | 56.9 | |
| ≥$47.6 | 305 | 32.7 | 628 | 67.3 | |
Note: based on 3,734 elderly Medicare beneficiaries aged 65 years and above with type 2 diabetes mellitus, who were continuously enrolled in the Humana Medicare prescription drug plans for 18 months between 2007 and 2011 and added rapid acting insulin to their oral antidiabetic drugs regimen. Significant group differences by multiple versus single prescription for rapid acting insulin were tested using chi-square tests.
A1C: glycated hemoglobin; aDCSI: adapted-Diabetes Complications Severity Index; ER: emergency room; HMO: health maintenance organization; OAD: oral antidiabetic drug; PFFS: private fee-for-service; PPO: preferred provider organization; RAI: rapid acting insulin.