Hypertension and diabetes diagnosis rates, IRRs and difference-in-difference post-ACA versus pre-ACA by Medicaid expansion status
| Hypertension diagnosis | Diabetes diagnosis | |||
| Pre-ACA | PostA-ACA | Pre-ACA | Post -ACA | |
| Non-expansion states | ||||
| Unadjusted rate per 100 patients per year | 7.0 | 5.5 | 0.8 | 0.9 |
| Adjusted rate* per 100 patients per year | 5.5 | 5.2 | 0.6 | 0.7 |
| Post-ACA versus pre-ACA IRR 95% CI | 0.94 (0.91 to 0.97)† | 1.28 (1.18 to 1.38) † | ||
| Expansion states | ||||
| Unadjusted rate per 100 patients per year | 4.7 | 4.4 | 0.6 | 0.7 |
| Adjusted rate* per 100 patients per year | 4.6 | 4.9 | 0.7 | 0.8 |
| Post-ACAt versus pre-ACA IRR 95% CI | 1.07 (1.03 to 1.10)† | 1.25 (1.16 to 1.34) † | ||
| Difference in difference (DID) | ||||
| Expansion versus non-expansion, DID 95% (CI) | 1.14 (1.11 to 1.18)† | 0.98 (0.91 to 1.05) | ||
*Generalised estimating equation Poisson models adjusted for year and primary community health centre patient population demographics (ie, clinic-level distributions of race/ethnicity, sex, age, most frequent insurance coverage and % federal poverty level).
†Statistically significant p<0.05.
‡Incidence rate was defined as number of new diagnoses at a clinic over person-time at risk.
ACA, Affordable Care Act; CI, confidence interval; IRR, incidence rate ratio.