Discussion

The current study represents one of few studies focusing explicitly on outcomes among SNF-OPAT patients and shows that healthcare system utilization and adverse health outcomes of these patients are high. The largest US-based OPAT studies published since

2000 ^{Reference Norris, Shrestha, Allison, Keller, Bhavan, Zurlo, Hersh, Gorski, Bosso, Rathore, Arrieta, Petrak, Shah, Brown, Knight and Umscheid1} , ^{Reference Schmidt, Hearn, Gabriel, Spencer and McCurdy6–Reference Keller, Williams and Gavgani8} primarily focused on outcomes among patients receiving OPAT at home or an infusion center. The 30-day (29%) readmission rate identified in the current study was substantially higher than the 30-day readmission rates (<20%) reported in three studies (n = 651) recovered from our review. ^{Reference Schmidt, Hearn, Gabriel, Spencer and McCurdy6–Reference Keller, Williams and Gavgani8} The 30-day mortality rate observed in the current study (5%) is similar to that reported in studies recovered from our review (4.5%–6.1%). ^{Reference Townsend, Keller and Tibuakuu7} While a previous study found no statistically significant difference in mortality rate at 30 and 90 days, the 90-day mortality rate observed in the current study was twice as high (8.9%). ^{Reference Townsend, Keller and Tibuakuu7}

The high rate of adverse outcomes observed among SNF-OPAT patients in the current study may not be surprising, given these patients are older and have more comorbidities compared to patients receiving OPAT in other settings. Nearly half of the ED encounters and readmissions observed were for OPAT- or infection-related factors, which are partially avoidable with close follow-up. ^{Reference Palms and Jacob9} A high volume of contact between the ID clinic and SNF nursing staff was identified in this study. However, the average face-to-face follow-up interval of 3 weeks (median: 22 days, IQR: 15) suggests a low intensity of direct contact between patients and providers. A recent study demonstrated a lower risk of hospital readmission for patients whose OPAT follow-up was conducted by an ID-trained provider rather than a nurse but highlighted a statistically significant decrease in those discharged to SNF. ^{Reference Palms and Jacob9} Although the SNF setting should theoretically provide a “safer” environment for OPAT, our findings question whether shorter interval follow-up can positively influence clinical outcomes such as readmission rates. While there are clear logistical and financial barriers to more frequent follow-up with this patient population, more liberal use of telehealth is an approach that may enhance the safety of SNF-OPAT, though existing regulations and payment structures remain uncertain. ^{Reference Ford, Jolles, Heller, Langenstroer and Crnich10}

The current study has several limitations, including a relatively small study population recruited from a single medical center and an inability to evaluate outcomes among patients who received post-discharge follow-up at another facility or were lost to follow-up. Additionally, study data was from 2016–2018. The intensity of post-hospital ID follow-up may have increased with wider implementation of telemedicine in SNFs during the COVID-19 pandemic and through expansion of other communication modes. Lastly, the absence of a comparator for non-SNF-OPAT ED visits, readmissions, face-to-face follow-up, and telephone encounters (including reason for contact and time spent) and lack of comprehensive outpatient care coordination evaluation present additional limitations.

The current study suggests that an intervention worth studying in SNF-OPAT patients includes closer post-discharge ID follow-up although future studies that directly compare outcomes of age- and comorbidity-matched patients receiving OPAT in other settings are needed.