Elderly, haemato-oncology patients often require antibiotic stewardship despite infectious disease referral

Older patients and those with haemato-oncology conditions are less likely than surgical patients to be referred to infectious disease (ID) physicians within 48 hours of hospital admission. Furthermore, they appear to be more likely to require antibiotic stewardship programmes (ASP) due to inappropriate type or duration of antibiotic therapy despite ID consultations, a retrospective cross-sectional study from Singapore showed.

The researchers looked at 6,490 referrals to ID physicians that took place at Singapore General Hospital between January 2016 and 2018. Most of these referrals were from medical departments (47.0 percent), followed by surgical (36.7 percent), haemato-oncology (14.2 percent), and transplant (2.1 percent) departments. Mean time between admission and ID referral was 6.69, 8.66, 9.15, and 6.31 days for the medical, surgical, haemato-oncology, and transplant departments, respectively.

Early referrals to ID specialists, defined as referrals within 48 hours of hospital admission, occurred in 18.1 percent of cases. By discipline, 17.9, 18.9, 13.7, and 39.6 percent of referrals from the medical, surgical, haemato-oncology, and transplant departments were made within 48 hours of admission. [Trop Med Infect Dis 2019;doi:10.10.3390/tropicalmed4040137]

Despite referral to an ID physician, 23.1 percent of patients from the haemato-oncology department required an ASP intervention due to inappropriate antibiotic usage. This rate was higher compared with patients from the surgical (17.7 percent), medical (13.7 percent), and transplant (6.0 percent) departments.

Multivariate analyses showed that patients who were referred from the haemato-oncology department had a reduced likelihood of early referrals to ID specialists compared with those from the surgical department (adjusted odds ratio [adjOR], 0.69, 95 percent confidence interval [CI], 0.55–0.85; p<0.001) but were more likely to require ASP intervention (adjOR, 1.44, 95 percent CI, 1.19–1.73; p<0.001). Similar findings were noted for older patients (age ≥60 years), who had both a lower likelihood of early ID referral (adjOR, 0.63, 95 percent CI, 0.55–0.72; p<0.001) and a higher likelihood of requiring ASP intervention (adjOR, 1.17, 95 percent CI, 1.02–1.35; p=0.025).

“Given that early antibiotic administration is associated with higher survival rates in the context of febrile neutropenia and that having a haematological or oncological condition is associated with high risk of subsequent clinical deterioration and unplanned readmission, early ID specialist referral should be a part of efforts to ensure that this group of patients receives early and appropriate antibiotic therapy,” recommended the researchers.

The higher risk of ASP requirement coupled with the lower risk of early ID referral in the elderly is also a matter of concern, with previous research demonstrating reduced mortality with prompt ID referral in this population, added the researchers. [Eur J Clin Microbiol Infect Dis 2017;36:625-633]

They suggested that “concern that ID specialists may disagree with early usage of broad-spectrum antibiotics, especially amongst elderly patients who may present with more severe illness at initial presentation” could explain the hesitance behind referring elderly patients to ID physicians.

Previous studies have shown that referral to ID specialists within 48 hours of admission was associated with reduced mortality, readmission, and hospital and intensive care unit duration of stay. [Clin Infect Dis 2014;58:22-28]

“[Despite this], less than one-fifth of ID specialist referrals [in this study] were made early,” noted the researchers. Furthermore, almost 17 percent of patients required ASP intervention despite ID physician consultation. “This reflects a substantial discordance between primary physicians and ID specialists in antibiotic choice,” they said.

“Elderly patients and haematology/oncology patients can be referred to ID specialists earlier and their antimicrobial regimens further optimized, perhaps by fostering closer cooperation between ID specialists and primary physicians,” they said.