Associations of SNF Quality Ratings With 30-Day Rehospitalizations and ED Visits

Skilled nursing facilities (SNFs) provide care to many patients, usually older patients with complex conditions, and SNFs are increasingly used as a transitional care setting after hospitalization. A common goal among caregivers is to decrease time in the acute care setting in the hospital and reduce readmissions.¹ This population has high rates of acute and unplanned health care use, and approximately one-fifth of patients return to the hospital from SNFs.¹ In an analysis of Medicare data for SNFs across five states, 28.6% of patients were readmitted, and almost half the readmissions occurred within 7 days of hospital discharge. In addition, 3.8% of patients died, and only 60% ultimately returned home.² Because readmission is potentially avoidable for at least 40% of patients,^1,3-7 readmission rates and emergency department (ED) visits are increasingly used as markers of quality of care for this population. 

In 2002, the Centers for Medicare & Medicaid Services (CMS) introduced Nursing Home Compare, a publicly available website that provides ratings of CMS-certified nursing homes (NHs) across the United States. Nursing Home Compare details specific quality measures for residents receiving post-acute or long-term care (LTC). This system was updated in 2008 to include the 5-Star Quality Rating System, which gives an overall quality rating and individual ratings for health inspections, staffing, and clinical quality measures (scale, 1-5 stars).⁸ Since its introduction, this system has influenced consumer demand for NHs and appears to have increased demand for 5-star-rated facilities.⁹ However, a higher overall quality rating has not been associated with a better quality of life for long-term residents,¹⁰ nor do the ratings reflect consumer satisfaction ratings.¹¹ 

Few studies have evaluated clinical outcomes and the updated components of the 5-star rating system. Some studies have shown that overall quality,^12,13 staffing,^13-15 and quality measures ratings^12,14 influenced risk of hospital readmission, whereas others have shown that quality measures,¹⁶ staffing, and health inspection ratings did not.¹² These studies were usually limited to patients with specific medical conditions such as heart failure (HF), did not control for provider care processes at the NH, or did not focus on ED visits. 

We conducted this study to determine the relationship between overall quality and individual component ratings of SNFs and the outcomes of rehospitalization and ED visit within 30 days for patients who were discharged to SNF for postacute care. We also aimed to evaluate which components of the 5-star rating (ie, health inspection, staffing, and quality measures ratings) were significantly associated with these outcomes.

 Study Design and Participants

This is a retrospective cohort study of adult (aged ≥ 18 years) patients discharged from Mayo Clinic (Rochester, MN) to nine local SNFs that are served by the Division of Employee and Community Health at Mayo Clinic from January 1, 2013, through March 31, 2016. We determined admission to the SNF by using the administrative database and confirmed admission with billing data. We included only patients whose hospital discharge date was the same as the SNF admission date to ensure that patients were directly discharged from the hospital to the SNF for postacute care. All patients who are treated at our institution are asked to provide consent for chart review for medical research purposes. We excluded patients who declined consent for chart review. Patient and SNF data were deidentified to maintain anonymity of patients and facilities. This study was approved by the Mayo Clinic Institutional Review Board.

We obtained patient-level data from the administrative database and electronic health records (EHRs), including age, sex, length of stay, hospital stays or ED visits in the preceding 6 months, and comorbid conditions as categorized by the Charlson Comorbidity Index.¹⁷ Parts of the study data were collected and managed with electronic data capture tools (REDCap) hosted at Mayo Clinic.¹⁸ 

A total of 4169 patients were selected for the study, of whom 246 chose not to have their health records reviewed for research purposes and were excluded. 

We obtained ratings data for CMS-certified SNFs from the publicly available Nursing Home Compare website.¹⁹ We used ratings data from nine of 13 SNFs within 25 miles of Rochester. We excluded one SNF affiliated with our institution because it used a different provider care model, one SNF because it was a new facility with no ratings available when this study was initiated, and two other SNFs because they were not covered by Mayo Clinic providers. The Division of Employee and Community Health provides similar postacute care at all nine SNFs included in the current study; providers are from the Department of Family Medicine and the Division of Community Internal Medicine at Mayo Clinic. On-site medical care at the SNFs was provided by a core group of geriatric medicine providers—which consisted of physicians, nurse practitioners, and physician assistants—from the Department of Community Health. After-hours coverage was provided via phone coverage and an on-call system with physicians from the Division of Employee and Community Health.

The data included overall quality ratings and individual ratings for health inspections, staffing, and clinical quality measures (Table 1). The health inspection rating, based on the results of the three most recent, annual independent inspections, forms the core of the overall quality rating.⁸ The staffing rating is based on registered nurse (RN) hours per resident per day and total staffing hours (RNs, licensed practical nurses, and nurse aides) per resident per day. The quality measures rating is based on a combined score generated from a subset of the quality measures recorded by CMS in the Minimum Data Set and Medicare claims data; these quality measures are specifically related to the clinical and functional status of the residents, and nine measures pertain to residents receiving postacute care. The overall quality rating is a composite score; the health inspection rating forms the core of the overall quality rating and is adjusted higher or lower on the basis of the staffing and quality measures ratings.⁸ To control for variation among states, only a percentage of facilities in a given state can receive a 5-star health inspection rating, and the top 10% of facilities for health inspections rating are awarded a 5-star overall quality rating on the basis of their relative performance within the state. 

Outcomes measured were rehospitalizations and ED visits within 30 days of hospital discharge. The discharge date of the index hospitalization was the first day of the 30-day period. We used billing data to determine 30-day rehospitalization after admission to the SNF, and we confirmed rehospitalization by the presence of a discharge note in the EHR. ED visits were determined in a similar manner by using the billing codes in the EHR. We used International Classification of Diseases, Ninth Edition, codes through September 30, 2015, and International Classification of Diseases, Tenth Edition, codes afterward. 

Data Analysis

Baseline demographic and clinical variables were summarized as number (percentage) for categorical variables or categorized and reported as number (percentage) for continuous variables. We used Cox proportional hazards models to examine unadjusted and adjusted relationships between overall quality ratings and 30-day rehospitalizations and ED visits. To de-identify SNFs and facilitate the analysis, we categorized SNFs as receiving 1- to 2-star ratings (“group A”) or 3- to 5-star ratings (“group B”). Analysis was conducted at the patient level and adjusted for age, sex, Charlson Comorbidity Index (< 6 or ≥ 6), and number of ED visits and hospital stays in the previous 6 months (0, 1-3, or ≥ 4). For the analysis, patients were assigned to ratings groups A or B on the basis of their SNF’s rating on their hospital discharge day.

To examine the association between the individual component ratings and outcomes, we created an adjusted model that included all five ratings and all covariates (age, sex, Charlson Comorbidity Index, prior 6-month hospital and ED visits). We also separately examined five univariate (unadjusted) models, each of which included one of the five ratings. The Charlson Comorbidity Index score was treated as a continuous covariate for analysis in the Cox proportional hazards model but was dichotomized (< 6 or ≥ 6) only for data-presentation purposes. All statistical analysis was performed with JMP statistical software version 13 (SAS Institute Inc).

 The study cohort included 3923 adult patients who were discharged from Mayo Clinic to nine SNFs in the greater Rochester (MN) area during the study period. Of these patients, 61.1% were women, 69.2% were aged 75 years or older, and 24.4% had a Charlson Comorbidity Index > 6 (Table 2). 

Rehospitalizations

Among the total patient population, 709 patients (18.1%) were readmitted within 30 days. Of these, 351 patients (49.5%) had from one to three hospital stays in the prior 6 months and 32 patients (4.5%) had four or more hospital stays. In terms of ED visits, 314 patients (44.3%) presented one to three times in the prior 6 months and 61 patients (8.6%) presented four or more times. 

The rate of 30-day readmission was 16.8% for patients in higher-rated facilities for the overall quality rating compared with 20.3% for patients in lower-rated facilities (Table 3). In the adjusted analysis, patients in higher-rated facilities had a lower risk of 30-day rehospitalization than patients in lower-rated facilities (hazard ratio, 0.87; 95% CI, 0.76-0.99). Quality measures, health inspection, and staffing ratings were not significantly associated with rehospitalization.

ED Visits

In the adjusted analysis for overall quality rating, patients in higher-rated facilities had a 14% lower risk of ED visits than patients in lower-rated facilities (Table 4). Patients in higher-rated facilities for clinical quality measures had a 20% lower risk of ED visits than patients in lower-rated facilities. These findings remained significant after adjustment for patient factors. Health inspection and staffing ratings were not significantly associated with ED visits. 

This retrospective study of hospitalization, ED visits, and CMS ratings of SNFs showed that patients in SNFs with higher overall quality ratings (eg, 3-5 stars) had lower risk of 30-day rehospitalization and ED visits compared with patients in lower-rated facilities (eg, 1 or 2 stars), even when the models were adjusted for patient and clinical factors. Higher overall quality ratings were associated with a 13% lower risk of rehospitalization and a 14% lower risk of ED visits. 

Our study had several notable strengths. It included a large cohort served by a single health care delivery system, which may have controlled for variations in provider care processes that may have influenced the studied outcomes. This is a novel approach compared with previous studies, which evaluated data from several health care providers. Our institution’s EHR system allowed us to accurately capture clinical outcomes, including ED visits. All patients were transferred to a single center, which permitted us to capture data on all ED visits and hospital readmissions. 

Previous studies of overall quality ratings focused on re-amission risk. One study used unadjusted models and Medicare data from US patients with HF residing in SNFs to show that the risk of readmission was 8% higher for patients in overall 1-star-rated SNFs than patients in 5-star-rated SNFs, but this association was weaker in the fully adjusted model.¹² Notably, the investigators evaluated 90-day readmission and not 30-day readmission, as in the current study and other previous studies.

A recent national study of 30-day readmissions for NH patients with pneumonia, HF, and acute myocardial infarction (AMI) showed that the overall quality rating was significantly associated with readmission risk.¹⁵ An increase in the overall quality rating by 1 star was associated with a decrease in the standardized readmission ratio of 0.26% for patients with AMI, 0.73% for patients with HF, and 0.45% for patients with pneumonia.¹⁵ Similarly, in their study of an orthopedic cohort, Kimball et al¹³ used Medicare data to show that patients admitted to overall 5-star-rated SNFs after total knee arthroplasty and total hip arthroplasty had hazard ratios of 0.76 and 0.64, respectively, for readmission relative to patients admitted to overall 1-star-rated SNFs.

Our study findings build on these results and confirm the lower risk of readmission in a broad clinical cohort that was not limited to specific clinical conditions. Overall, older patients composed a larger proportion of the readmitted cohort. Patients in the oldest age group who were readmitted accounted for 6% (n = 245) of the entire cohort, whereas patients in the youngest age group who were rehospitalized accounted for less than 1% (n = 26). 

When we evaluated the individual components of these ratings, patients in higher-rated facilities for quality measures ratings also had a 20% lower risk of ED visits. In the adjusted models, the quality measures rating was no longer significantly associated with 30-day rehospitalization. Staffing and health inspection ratings were not significantly associated with risk of rehospitalizations or ED visits. A possible explanation for these findings is that the effects of these individual component ratings on our outcomes may have been attenuated by assigning facilities to groups A and B, which was done to maintain anonymity rather than analyze outcomes according to individual star ratings. 

Previous studies report conflicting results about quality measures ratings. A prior study of patients with HF in 17 SNFs in western Massachusetts reported that quality measures ratings did not correlate with 30-day readmission rates (risk-adjusted readmission rate of 10.2% for 1-star-rated facilities vs 8.8% for ≥ 2-star-rated facilities, P = .54).¹⁶ In another cohort of HF patients, patients in 1-star-rated facilities for quality measures had a 7% higher risk of readmission compared with patients in 5-star-rated facilities, although this risk was not associated with staffing or health inspection ratings.¹² In a national study of staffing that used readmission data for patients with pneumonia, HF, and AMI, a higher RN staffing rating was associated with a 0.19% decline in hospital readmissions for patients with AMI, 0.40% for patients with HF, and 0.21% for patients with pneumonia.¹⁵ The association with staffing was also noted in the aforementioned orthopedic study; when nurse staffing ratings increased, 30-day readmissions decreased.¹³ In their large study of national Medicare data, Neuman et al¹⁴ used unadjusted models to determine that patients in SNFs with higher inspection, staffing, and certain quality measures ratings had lower risks of readmission and death at 30 days. These outcomes were attenuated after the models were adjusted for patient, hospital, and facility characteristics. Patients in SNFs with the highest health inspection ratings had a 23.7% risk of 30-day rehospitalization or death compared with 23% for patients in the lowest-rated SNFs (P < .001), but the association with the staffing rating was not significant after adjustment.

Our study expands on this prior research and also examined the risk of ED visits. Unlike studies that used data from different health care systems and areas, our study mostly controlled for care processes at the clinical level because providers were from a single Division of Employee and Community Health and one health care system. 

The associations of quality measures and overall quality ratings with ED visits are novel. In the United States, NH residents account for approximately 2 million ED visits annually.²⁰ To our knowledge, only one previous study recently evaluated the relationship between Nursing Home Compare star ratings and potentially preventable admissions and ED visits.²¹ Notably, that study evaluated an LTC population, in contrast to our postacute population, and showed only a weak association between overall quality ratings and potentially preventable events.²¹ From our findings, one can hypothesize that day-to-day, facility-level factors, which are captured by quality metrics, have the most influence on patient outcomes (eg, ED visits). Until recently, NHs had no financial incentives to reduce their readmission rates²² or quality measures to evaluate outcomes, such as readmission or discharge to home or an LTC facility.²³ However, with the introduction of the Skilled Nursing Facility Value-Based Purchasing Program, CMS now pays SNF providers on the basis of quality of care.²⁴ Hence, there is a need to quickly identify those residents most at risk for readmission and intervene accordingly.

In addition, the SNF inspection process used to determine the individual ratings did not affect rehospitalization and ED visits in our cohort. This process is detailed, labor intensive, and costly because a team of health care professionals spends several days on site to perform an unannounced inspection.⁸ Our results suggest that inspection may not be so useful for the outcomes studied here.

This study has certain limitations. It was performed at a single health care delivery system that provides care to a population composed mostly of white patients, albeit at different SNFs with separate management structures, which may include differences in nursing and in facility or resource factors that cannot be controlled.²⁵ Also, patient-level factors, such as length of stay, timing of rehospitalization, and reason for index hospitalization, may have influenced the results and were not considered and may limit generalizability. However, use of a single health care system controlled as much as possible for variations in provider factors and health care processes  that may have influenced the studied outcomes. Administrative data are also subject to inaccuracies in medical coding and NH reporting. Patients may have obtained care at another institution, and therefore data may be missing. Also, for analytic purposes, the ratings were obtained at a single time. Furthermore, because the health inspection rating reflects the results of the three most recent annual surveys, SNFs may have implemented changes to improve their practices that are not yet reflected in the rating. Because the health inspection rating substantially affects the overall quality rating, lower-rated facilities in our area may have performed better on the staffing and quality measures ratings, but this would not have improved their overall quality rating. 

The risk of 30-day rehospitalization was lowest for patients in SNFs with higher overall quality ratings. The risk of ED visits was lower for patients in SNFs with higher overall quality and higher quality measures ratings, thereby indicating that patient-level factors are most influential. These findings will help inform acute care providers and NH administrators as we work toward fewer rehospitalizations and ED visits for patients. Our results warrant confirmation in other care settings and locations.

Authors:
Mairead M Bartley, MB, BCh, BAO, MD¹• Parvez A Rahman²• Curtis B Storlie, PhD²• Paul Y Takahashi, MD¹• Anupam Chandra, MD¹

Affiliations:
¹Division of Community Internal Medicine,
Mayo Clinic, Rochester, MN
²Division of Biomedical Statistics and
Informatics, Mayo Clinic, Rochester, MN

Disclosures:
Dr Takahashi serves on the medical board of Axiall, LLC. The other authors report no relevant financial disclosures.

Address correspondence to:
Anupam Chandra, MD
Division of Community Internal Medicine,
Mayo Clinic
200 First St SW Rochester, MN 55905
Phone: (507) 284-5944
Email: Chandra.anupam@mayo.edu