As of April 28, 2020, there have been nearly 3 million confirmed cases of coronavirus disease 2019 and 202,597 deaths globally, with 960,916 confirmed cases and 49,170 deaths in the United States. 1 Residents of long-term care (LTC) facilities have been shown to be highly vulnerable to respiratory disease outbreaks, such as those of influenza or other common human coronaviruses. 2, 3 Current evidence suggests that COVID-19 disproportionately affects older adults and persons with chronic health conditions, leading to higher attack rates and more severe adverse outcomes, such as deaths, among them. [4] [5] [6] Nursing home residents are characterized by advanced age, more frequent and complex chronic disease patterns, and highly impaired physical, cognitive, and immune-system functions, which together put them at the greatest risk of severe COVID-19 infections. [7] [8] [9] After the identification of the first confirmed COVID-19 case in a skilled nursing facility in Seattle, Washington on February 28, a case investigation conducted by the Public Health-Seattle and King County and the Centers for Disease Control and Prevention (CDC) 7 reported that as of March 18, a total of 167 confirmed COVID-19 cases affecting nursing home residents, care providers, and visitors were found to be epidemiologically linked to that facility, and that over half of infected residents were hospitalized and a third dead. By April 23, 4,069 LTC facilities in 36 states have been hit by COVID-19 and over 10,000 deaths of LTC residents and staff have been reported in 23 states. 10 Research is urgently needed to understand COVID-19 transmissions in LTC facilities and to identify important facility characteristics that may be associated with the spread of the novel coronavirus and case fatality among residents. Strong evidence and broad consensus exist that higher nurse staffing levels in nursing homes, especially higher registered nurse (RN) hours,
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improve safety of care and resident outcomes. [11] [12] [13] [14] Residents in nursing homes with better quality of care are also shown to have better health outcomes such as reduced risks of pressure ulcers and mortality. [15] [16] [17] Moreover, it is widely reported that nursing homes caring for a disproportionately high number of disadvantaged residents, including Medicaid residents and racial or ethnic minority residents, tend to have more limited financial and clinical resources that lead to poorer quality and safety outcomes for their residents. [18] [19] [20] [21] [22] [23] However, COVID-19 is a novel, rapidly-evolving pandemic, and evidence regarding COVID-19 related outcomes and their variation among nursing homes is lacking.
This study describes variations in COVID-19 confirmed cases and deaths among residents in Connecticut nursing homes through April 16, 2020, and evaluates their associations with important nursing home characteristics. We test the hypotheses that nursing homes with higher RN staffing level and better overall quality of care have fewer confirmed cases and deaths but facilities in which Medicaid-paid residents and racial/ethnic minority residents predominate have worse COVID-19 outcomes.
We first obtained data on COVID-19 laboratory-confirmed cases and associated deaths in each of Connecticut's nursing homes as of April 16, 2020. These data were collected and regularly updated by Connecticut Department of Health and Human Services (https://data.ct.gov/Health-and-Human-Services/Nursing-Homes-with-Residents-Positive-for-COVID-19/wyn3-qphu) and were also published in a recent news report. 24 These data were then linked to the Nursing Home Compare (NHC) data files (updated on March 31, 2020), 25 a data Accepted Article This article is protected by copyright. All rights reserved. system published by the Centers for Medicare and Medicaid (CMS) for tracking and reporting nurse staffing, quality of care, findings of state government inspections of nursing home care practices, and other facility characteristics. 16 We obtained the following variables in the NHC files that were potentially associated with resident safety and health outcomes: 12, 13, [15] [16] [17] [18] [19] [20] [21] [22] total number of beds, average daily resident census, ownership status (for-profit versus non-profit or government-owned), affiliation with a chain (yes/no), percentage of Medicare residents, percentage of Medicaid residents, average staffing level (hours per resident day) for registered nurse (RN) in 2019, average total nurse staffing level (including RN, licensed practical nurse, and certified nursing assistant) in 2019, and five-star ratings for overall quality of care.
RN and other nurse staffing levels were calculated based on daily resident census and CMS' Payroll-Based Journal (PBJ) system which allows nursing homes to electronically submit the number of hours that care workers (including agency and contract staff) are paid to work each day. 26 As required by Section 6106 of the Affordable Care Act, the payroll-based data are submitted quarterly on different types of nursing staff and are subject to audit to ensure accuracy. The five-star ratings aggregate alternative nursing home quality measures into a rating system of one to five stars, with more stars indicating better quality. 27 Specifically, ratings were first developed to summarize three separate domains of "quality": deficiency citations assigned during annual and complaint inspections; a set of clinical outcomes of residents based on Minimum Data Set (MDS) assessments; and nurse staffing to resident ratios. The overall fivestar ratings were then derived from these domain-specific ratings using CMS developed algorithm. 27
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We used data from the LTCFocUS.org website to obtain two additional variables. These data were created by the Center for Gerontology and Healthcare Research at Brown University by combining multiple sources of resident and nursing home records such as the MDS for all nursing home residents, Medicare enrollment file, and CMS maintained facility files. The first variable we obtained was percentage of racial and ethnic minority residents (American Africans, Hispanics, Asians or Pacific Islanders, and American Indians or Alaskan Natives) in the nursing home which was originally defined using the race and ethnicity information in the MDS and Medicare enrollment databases. We also obtained a variable for facility-level case mix, which was derived from the RUG (resource utilization group) classification of all residents in the nursing home; the case-mix index was calculated by averaging the acuity scores of all residents (approximated by the relative staff time demanded by the resident) in the facility, with higher value indicating higher average acuity.
We downloaded data of the numbers of lab-confirmed cases and deaths of COVID-19 in all counties in the US, as published by the New York Times (https://github.com/nytimes/covid-19-data). These numbers have been compiled and updated in real time by the Times based on reports from state and local health agencies since the first reported coronavirus case in Snohomish County, Washington on January 20, 2020. 28 Using these data we calculated, for each of the eight counties in Connecticut, the total number of confirmed COVID-19 cases as of April 16, 2020 (with and without nursing home confirmed cases). Similarly, we calculated the total number of COVID-19 deaths in the county, with and without nursing home deaths. Lastly, we
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used the 2018 Area Healthcare Resource File (https://data.hrsa.gov/topics/health-workforce/ahrf) to obtain information about county population size.
We examined the distributions of nursing home COVID-19 confirmed cases and deaths, as well as other nursing home characteristics overall, by number of confirmed cases (0, 1-10, and 11-69), and by number of COVID-19 related deaths (0, 1-5, and 6-15). We also summarized county characteristics and plotted the percentages of COVID-19 cases and deaths that were attributed to nursing home residents in each county.
Multivariable analyses determined the associations of four independent variables with numbers of confirmed cases and deaths in nursing home (dependent variables in separate models). The four independent variables were nursing home RN staffing, overall quality of care We fit separate two-part models at the nursing home level to account for the fact that a relatively large number of nursing homes had zero confirmed case and death. 29 The first part of the models was a generalized linear model with a logit link function and assuming binomial distribution, which estimated the likelihood of a nursing home having at least one confirmed case (or death). The second part is a count model assuming a Poisson distribution, which estimated the number of cases (or deaths) conditional on at least one confirmed case (or death) that was found in the nursing home as of April 16, 2020. Both parts of the model controlled for the same
This article is protected by copyright. All rights reserved. nursing home covariates (Table 1) as well as two county covariates: total number of confirmed cases (or deaths) in the county other than nursing home cases (deaths) and county population size.
After model estimation, we obtained the predicted counts of confirmed cases and deaths for all nursing homes and plotted each predicted count against the independent variables.
In all 215 Connecticut nursing homes (Table 1) Similar trends were found for confirmed deaths. Nursing homes with more confirmed cases or deaths were also more likely to be large, for-profit facilities affiliated with a chain and having a higher resident census. Table 2 shows that by April 16, the cumulative number of confirmed cases was 3.0 per 1000 population in Connecticut but ranged from 0.7 to 7. cases who were nursing home residents in Connecticut was 11.2% (ranging from 0 to 19.5% over counties), but the corresponding proportion for deaths was 38.7% in the state with a range from 0 to 50% over counties (Supplementary Figure S1 ).
Multivariable analyses showed that RN staffing, five-star ratings, and concentrations of Medicaid and racial/ethnic minority residents in the nursing home were not statistically significantly associated with the likelihood of having ≥1 confirmed case in the facility, after controlling for facility and county covariates ( Supplementary Figure S2 , panel A similarly shows the predicted number of confirmed cases from the two-part model and demonstrates more confirmed cases in lower-star nursing homes and nursing homes with higher concentrations of socio-demographically disadvantaged residents. Table 3 also shows that these key nursing home characteristics were not significantly associated with the likelihood of one or more COVID-19 deaths in nursing home. However,
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among facilities with at least one death, every 20 minutes increase in RN staffing of the nursing home significantly predicted a 26% reduction in COVID-19 deaths (IRR=0.74, 95% CI 0.55-1.00, p=0.047). Furthermore, RN staffing level was negatively associated with the overall predicted number of deaths (p=0.067 in joint test of the two-part model; Figure 1, panel B ).
Supplementary Figure S2 shows the tendencies of higher predicted numbers of deaths in lowerstar nursing homes and nursing homes with higher concentration of socio-demographically disadvantaged residents, although group differences were not statistically significant.
By April 16, 2020, COVID-19 cases have occurred among residents in 50%, and deaths in 40%, of Connecticut nursing homes. The numbers of confirmed cases and deaths vary substantially over nursing homes, and higher registered nurse staffing is strongly associated with fewer cases and deaths. Nursing homes with lower quality ratings and caring predominantly for Medicaid or racial and ethnic minority residents tend to have more confirmed cases in multivariable analyses. However, current data do not support the hypothesis that these nursing homes have excessively high number of confirmed deaths.
Connecticut is among the earliest states to publicly report COVID-19 cases and deaths in their states' nursing homes, and Connecticut's report is granular enough to allow for evaluation of variations over facilities. In an effort to fill the information gap for nursing home residents, their families, and policymakers, CMS released guidance on April 19, 2020 requiring nursing homes to report COVID-19 cases directly to CDC and to appropriately notify residents and their representatives of conditions at the facilities. 30 Although the federally reported data are not yet available, a study by the Kaiser Family Foundation 10 documented that by April 23, 36 states
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were reporting some level of data about coronavirus cases and deaths in long-term care facilities.
The Kaiser study further reported that the LTC facility shares of total COVID-19 cases and deaths were 11% and 27%, respectively, but varied substantially over states. Our study found that in Connecticut, the nursing home shares of total confirmed cases and deaths are 11% and that nursing homes in better compliance with these multifaceted care standards and performing better in resident-oriented quality measures are more able to contain the spread of coronavirus among their residents, although their abilities to prevent COVID-19 related deaths are not found superior compared to other nursing homes.
Disparities in quality of care have long been documented in nursing homes, with consistent evidence showing that facilities caring for disproportionately higher numbers of Medicaid and racial/ethnic minority residents tend to be located in communities of lower socioeconomic status, be financially strained, and have worse resident outcomes. [18] [19] [20] 32, 33 Thus, our finding of the higher cumulative incidences of COVID-19 infection in these facilities is likely a new manifestation of these longstanding disparities. In addition, early data suggested less social distancing in lower-income neighborhoods, 34 possibly due to the lack of job security and other disadvantages, and higher COVID-19 contraction rate among racial minorities. 35 common. Also, current federal regulations require nursing homes to have an RN on duty at least 8 hours a day and 7 days a week. Although this staffing requirement may be hard to raise nationally, nursing homes able to increase their RN hours should consider doing so for more effective control of COVID-19 outbreaks.
Furthermore, in the face of the COVID-19 pandemic, nursing homes caring for more socio-demographically disadvantaged residents may be more likely than other facilities to experience severe shortages of staff, personal protective equipment (PPE), and medical equipment, as well as other issues such as poor testing capacity, delayed diagnosis, lack of access to medical treatment, and high risk of cross-infection among residents and staff. Thus, national and local efforts to bolster healthcare capacity in nursing homes should target these facilities; other supports to mitigate coronavirus transmission in LTC facilities, such as staff training for proper use of PPE, may also target these highly-strained facilities.
This study has several limitations. First, our analyses focused on Connecticut nursing homes and results should be generalized to other states with caution. However, in the current absence of national COVID-19 data for nursing homes, findings in this study provide timely evidence to inform policies and practices. Second, the observational study design allows for estimation of associations only, which may be biased by unmeasured confounders such as number of tests done in the nursing home (likely limited due to insufficient testing capacity in the state) and actual infection control and prevention practices in individual facilities. Finally, the lack of significance in the associations of nursing home star ratings and concentrations of disadvantaged residents with predicted COVID-19 deaths may reflect insufficient power in multivariable analyses.
In conclusion, nursing homes with higher RN staffing and quality ratings have the potential to better control the spread of the novel coronavirus and reduce deaths. Thus, inspections of nursing home infection control practices may target facilities with lower RN staffing and star ratings. Compared to other nursing homes, nursing homes caring predominantly for Medicaid or racial and ethnic minority residents tend to have more COVID-19 confirmed cases. Thus, efforts to help nursing homes combat the COVID-19 pandemic should prioritize these facilities.
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