Table 3.
Difference-in-differences analysis of all Medicaid and uninsured patients who underwent surgery for pancreatic cancer. Comparison is between pre- and post-expansion time periods in non-expansion and January 2014 expansion states.
| Non-Expansion States | Expansion States | Unadjusted | Adjusted | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2011–12 | 2015–16 | AD | RC (%) | 2011–12 | 2015–16 | AD | RC (%) | DID | p value | DID | p value | |
| Surgical patients (n) | 350 | 305 | 240 | 301 | ||||||||
| Proportion of all patients (%) | 17.75 | 16.51 | −1.24 | −6.96 | 18.31 | 19.20 | 0.89 | 4.86 | 2.13 | 0.26 | 2.05 | 0.28 |
| Charlson/Deyo Score (%) | ||||||||||||
| 0 | 60.29 | 69.18 | 8.89 | 14.75 | 67.08 | 60.47 | −6.62 | −9.87 | −15.51 | 0.01 * | −13.69 | 0.02 * |
| 1 | 30.86 | 22.62 | −8.23 | −26.68 | 27.50 | 28.57 | 1.07 | 3.90 | 9.31 | 0.07 | 8.11 | 0.13 |
| 2 | 6.86 | 3.61 | −3.25 | −47.40 | 4.17 | 4.65 | 0.48 | 11.63 | 3.74 | 0.14 | 3.16 | 0.22 |
| 3+ | 2.00 | 4.59 | 2.59 | 129.51 | 1.25 | 6.31 | 5.06 | 404.98 | 2.47 | 0.25 | 2.42 | 0.27 |
| AJCC clinical stage (%) | ||||||||||||
| 1 | 37.01 | 39.15 | 2.14 | 5.79 | 37.13 | 42.34 | 5.22 | 14.05 | 3.07 | 0.65 | 0.09 | 0.99 |
| 2 | 55.12 | 54.25 | −0.87 | −1.58 | 53.29 | 46.40 | −6.90 | −12.94 | −6.02 | 0.38 | −4.28 | 0.55 |
| 3 | 3.54 | 5.19 | 1.65 | 46.44 | 5.99 | 9.01 | 3.02 | 50.45 | 1.38 | 0.67 | 2.16 | 0.52 |
| 4 | 3.54 | 1.42 | −2.13 | −60.06 | 3.59 | 2.25 | −1.34 | −37.31 | 0.79 | 0.73 | 1.20 | 0.60 |
| Distance travelled (miles) | 46.28 | 35.77 | −10.51 | −22.71 | 27.16 | 25.90 | −1.26 | −4.63 | 9.25 | 0.24 | 7.42 | 0.33 |
| Diagnosis to treatment (days) | 20.67 | 23.92 | 3.24 | 15.69 | 18.33 | 26.56 | 8.22 | 44.85 | 4.98 | 0.12 | 3.68 | 0.26 |
| Treatment at academic program | 50.00 | 49.18 | −0.82 | −1.64 | 65.83 | 58.14 | −7.69 | −11.69 | −6.87 | 0.23 | −8.15 | 0.16 |
| AJCC pathologic stage (%) | ||||||||||||
| 0 | 0.91 | 0.34 | −0.57 | −62.34 | 0.91 | 0.00 | −0.91 | −100.00 | −0.34 | 0.69 | −0.23 | 0.80 |
| 1 | 8.16 | 12.97 | 4.81 | 58.99 | 9.55 | 8.77 | −0.77 | −8.10 | −5.59 | 0.12 | −6.35 | 0.08 |
| 2 | 84.89 | 82.25 | −2.64 | −3.11 | 83.18 | 85.96 | 2.78 | 3.35 | 5.42 | 0.22 | 5.71 | 0.20 |
| 3 | 2.11 | 2.05 | −0.07 | −3.17 | 3.18 | 1.75 | −1.43 | −44.86 | −1.36 | 0.44 | −0.93 | 0.61 |
| 4 | 3.93 | 2.39 | −1.54 | −39.17 | 3.18 | 3.51 | 0.33 | 10.28 | 1.87 | 0.39 | 1.80 | 0.41 |
| MIS approach (%) | 13.42 | 24.81 | 11.38 | 84.81 | 15.31 | 23.39 | 8.08 | 52.75 | −3.31 | 0.51 | −1.55 | 0.76 |
| Negative margin (R0, %) | 73.14 | 78.69 | 5.55 | 7.58 | 83.33 | 77.08 | −6.26 | −7.51 | −11.80 | 0.02 * | −11.69 | 0.02 * |
| Length of stay (days) | 11.54 | 8.92 | −2.61 | −22.66 | 11.48 | 10.09 | −1.39 | −12.09 | 1.23 | 0.32 | 0.79 | 0.53 |
| 30-day readmission (%) | 6.86 | 6.56 | −0.30 | −4.37 | 12.08 | 8.31 | −3.78 | −31.26 | −3.48 | 0.28 | −4.55 | 0.16 |
| 30-day mortality (%) | 2.00 | 1.64 | −0.36 | −18.03 | 3.33 | 0.66 | −2.67 | −80.07 | −2.31 | 0.14 | −2.19 | 0.17 |
| 90-day mortality (%) | 4.86 | 3.93 | −0.92 | −19.00 | 6.67 | 2.33 | −4.34 | −65.12 | −3.42 | 0.15 | −3.59 | 0.14 |
| Neoadjuvant therapy (%) | 12.29 | 28.85 | 16.57 | 134.85 | 10.42 | 31.89 | 21.48 | 206.18 | 4.91 | 0.29 | 5.34 | 0.25 |
| Adjuvant chemotherapy (%) | 61.14 | 59.02 | −2.13 | −3.48 | 61.67 | 64.78 | 3.12 | 5.06 | 5.24 | 0.36 | 2.53 | 0.66 |
AD=absolute difference (in miles, days, or %); AJCC=American Joint Committee on Cancer; DID=difference-in-differences; MIS=minimally invasive surgery; RC=relative change (% change between time periods).
*
indicates statistical significance.