Our findings reveal a marked geographic disparity that affects a subset of racial/ethnic minority populations in the United States. Hospitals in the US territories, on average, have significantly higher RSMRs than hospitals in the US states. The magnitude of differences across these rates raises concerns about differences in the quality of care. In comparison with the states, for every 100 AMI admissions in the US territories there are approximately 2 additional deaths, for every 100 HF admissions there is 1 additional death, and for every 100 pneumonia admissions there are 3 additional deaths. The higher mortality rates are not explained by the types of hospitals included or their lower use of guideline-recommended therapies. Furthermore, the higher mortality rates observed in the US territories are not the result of a few outlier institutions; virtually all of the territorial hospitals performed below the US national averages.
Notably, the US territories have lower federal insurance reimbursement rates compared with all of the US states.28,29
In 2003, the General Accounting Office found that Medicare spending averaged $6300 per enrollee in the US states compared with $2800 in the US territories.29
This study did not directly assess whether low reimbursement rates in the US territories contribute to low hospital performance in these regions. Still, it is important to consider the context of differential federal reimbursement policies. Specifically, the federal government has limited its Medicaid contribution to 50%, the lowest allowable percentage, for the US territories. In contrast to reimbursement policies for the US states, the federal government does not make any additional adjustments for lower per capita income in the US territories. The federal government also limits its contribution to a specific dollar amount in the US territories; there are no comparable “cap” policies in any US state or in the District of Columbia. Both of these discrepancies severely limit health care funding streams in the US territories, with consequences such as narrow Medicaid eligibility criteria and the elimination of Medicaid services that are commonly covered in many US states. Medicaid policies are particularly relevant to the Medicare population, given the growth of dual eligible residents in the territories.30
Puerto Rico faces additional policy challenges when compared with the US states and other territories because of Medicare policies that reimburse in-patient hospitalizations at rates lower than anywhere else in the nation.31,32
In addition, the territories have a limited ability to shape the policies that may ultimately influence health care quality; the US territories lack voting representation in the US Congress and residents cannot vote in national elections.33
We also found that risk-standardized readmission rates were higher in the US territories for AMI and PNE prior to adjustment. Again, almost all of the hospitals in the territories performed worse than the average in the US states, although these associations were not significant after adjusting for hospital characteristics and core process measure performance. Still, readmission rates for all the hospitals were high, and although the disparity was not as prominent as with the mortality measure, the need for improvement is clear.
Lastly, we found marked disparities in performance on the core process measures. These publicly reported measures assess compliance with a set of guideline-recommended therapies and actions that are associated with improved patient outcomes. They demonstrate lower quality care in the care of patients in the territories for each of the 3 conditions, representing substantial opportunities for improvement. As observed in prior work done in the United States, these differences in performance on core process measures explained only a small amount of the variation in mortality, indicating that many other factors play a role.34–37
Still, we included core process measures in our multivariable analysis because the association between processes of care and outcomes may have been different in the US territories and we could have missed important and potentially intervention-sensitive levers for change if they were not assessed. However, the fact that performance on these measures does not explain the higher mortality rates suggests that, beyond these processes, there are other aspects of care that are likely contributing to these differences.
Our study is one of the first to examine quality of care for hospitals located in the US territories; however, there are some limitations to consider when interpreting these findings. First, being located in a US territory may be a marker for geographic location on an island or unmeasured characteristics such as patient socioeconomic status; poverty is much more common in the territories.1,6
Although there is evidence that hospitals disproportionately providing care for lower socioeconomic status populations have similar mortality rates to hospitals providing care to higher socioeconomic status populations, this evidence does not include US territories and their corresponding low reimbursements for Medicare.8
Second, we examined AMI, HF, and PNE and our results may not be generalizable to other conditions. Still, the existence of high-quality CMS data in these clinical areas represents an opportunity to investigate hospital performance in the territories and establishes the foundation for future work in this area. Third, our measures were based on the experience of patients in Medicare FFS and our results may not extend to younger populations. However, this is an appropriate group to investigate, given the expanding proportion of patients older than 65 years and associated increasing health care costs. Fourth, our outcomes measures were based on models using administrative claims data. We did not have extensive patient-level data for patients in the US states or in the US territories and therefore could not take into account health behaviors, health literacy, or adherence across these populations. However, we assessed acute care processes and short-term outcomes, and comorbid conditions were well captured in our administrative claims data. Although there may be unmeasured patient characteristics in the territorial populations for which we do not account, the statistical models used in the outcome measures produce estimates that are good surrogates for estimates from a medical record model.9,11,37
In addition, the mortality measure, which is approved by the National Quality Forum, is designed to convey information about hospital performance and already adjusts for hospital case-mix.7,9
We also conducted several secondary analyses to assess whether our findings primarily reflected the experience of Puerto Rico, since it has the largest population of the territories; we found the disparities were consistent across all US territories.
Despite the national effort to address health care disparities through increased public reporting and standardizing hospital performance, hospitals in the US territories have been largely neglected. Improving health care outcomes in the US territories should be included in any comprehensive effort to tackle national racial/ethnic and other health care disparities. The striking disparity revealed in this study demonstrates that people living in the US territories are at a notable disadvantage compared with those in the US states. Importantly, these US possessions are legally restricted from full participation in the shaping of relevant US health care policy. The nation has a great responsibility to guarantee that residents on these islands have access to care that is at least of the same quality as care in the US states.