Table 4.
Choice of Second Medication after Starting Metformin or a Sulfonylurea in Traditional Medicare and Medicare Advantagea
| Metformin First | SU/Metformin Second | TZD Second | Insulin Second | Other Second | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TM | MA | Diff | TM | MA | Diff | TM | MA | Diff | TM | MA | Diff | |
| Metformin First | 53.7% | 61.5% | −7.8% | 5.4% | 5.6% | −0.2% | 11.2% | 10.8% | 0.4% | 29.7% | 22.0% | 7.7% |
| Region | + | + | + | |||||||||
| Northeast | 49.1% | 56.9% | −7.8% | 3.5% | 3.6% | −0.1% | 9.3% | 10.0% | −0.7% | 38.1% | 29.5% | 8.6% |
| Midwest | 61.4% | 62.8% | −1.4% | 4.6% | 4.9% | −0.3% | 11.6% | 12.5% | −0.8% | 22.4% | 19.9% | 2.5% |
| South | 54.8% | 62.7% | −8.0% | 6.0% | 5.4% | 0.6% | 10.7% | 10.8% | −0.1% | 28.5% | 21.0% | 7.5% |
| West | 50.2% | 62.4% | −12.2% | 6.6% | 8.2% | −1.7% | 13.3% | 10.4% | 2.9% | 30.0% | 19.0% | 11.0% |
| Plan Type | ||||||||||||
| Established | 54.4% | 60.5% | −6.1% | 5.3% | 5.7% | −0.5% | 11.6% | 11.0% | 0.7% | 28.7% | 22.8% | 5.9% |
| New | 53.3% | 62.1% | −8.7% | 5.5% | 5.6% | −0.1% | 11.0% | 10.7% | 0.2% | 30.2% | 21.6% | 8.6% |
| Plan Size | + | + | ||||||||||
| Small | 52.9% | 63.4% | −10.5% | 5.4% | 5.3% | 0.1% | 11.3% | 10.2% | 1.1% | 30.3% | 21.1% | 9.2% |
| Large | 54.4% | 59.7% | −5.3% | 5.4% | 5.9% | −0.6% | 11.0% | 11.4% | −0.4% | 29.2% | 22.9% | 6.3% |
| Sulfonylurea First | 58.6% | 62.5% | −3.9% | 5.5% | 6.0% | −0.5% | 14.3% | 14.3% | 0.0% | 21.6% | 17.2% | 4.4% |
| Region | + | + | ||||||||||
| Northeast | 59.1% | 62.2% | −3.1% | 3.5% | 3.9% | −0.4% | 12.7% | 12.6% | 0.2% | 24.6% | 21.4% | 3.3% |
| Midwest | 60.3% | 60.3% | 0.0% | 5.8% | 5.8% | 0.0% | 16.2% | 17.6% | −1.4% | 17.7% | 16.3% | 1.4% |
| South | 56.9% | 61.7% | −4.8% | 5.6% | 6.4% | −0.8% | 14.7% | 14.5% | 0.2% | 22.8% | 17.4% | 5.4% |
| West | 60.7% | 66.4% | −5.7% | 6.8% | 7.1% | −0.4% | 13.4% | 12.9% | 0.5% | 19.1% | 13.5% | 5.6% |
| Plan Type | ||||||||||||
| Established | 60.7% | 62.3% | −1.5% | 5.2% | 5.7% | −0.5% | 14.5% | 14.6% | −0.2% | 19.7% | 17.5% | 2.2% |
| New | 57.6% | 62.7% | −5.0% | 5.7% | 6.2% | −0.5% | 14.2% | 14.2% | 0.1% | 22.5% | 17.0% | 5.5% |
| Plan Size | + | + | ||||||||||
| Small | 57.2% | 62.3% | −5.1% | 5.4% | 6.1% | −0.6% | 14.8% | 14.4% | 0.4% | 22.6% | 17.3% | 5.4% |
| Large | 60.1% | 62.8% | −2.7% | 5.6% | 5.9% | −0.4% | 13.9% | 14.2% | −0.3% | 20.5% | 17.1% | 3.4% |
TM estimates are weighted to match MA distributions by age category, sex, race/ethnicity categories, and geography. Overall MA-TM differences (first rows) are statistically significant at p<.0001 for SU/metformin and other. For those who started an SU first, there were no significant differences for starting a TZD or insulin second. For those who started metformin first, the difference for those starting insulin second was significant (p<.01). Significant differences by region, plan age, and plan size are noted by (+), signifying p≤.01).
Other includes GLP-1 agonists, DPP-4 inhibitors, SGLT-2 inhibitors, Meglitinides, and D-Phenylalanine Derivatives.