Post-discharge impact of healthcare-associated infections in a developing country: A cohort study

To the Editor —The impact of healthcare-associated infections (HCAIs) on in-hospital mortality, morbidity, length-of-stay, and costs has been extensively reported. ^{1 , 2} However, few studies have focused on the follow-up of HCAI-affected subjects after discharge. Most studies have focused on the increased risk of readmissions to hospitals. ^{3 – 6} However, HCAIs may impact patient autonomy and the utilization of healthcare resources. ⁷

We conducted a cohort study aimed at identifying the impact of HCAIs among persons discharged after diagnosis of HCAI in a teaching in inner Brazil. Adult patients discharged from Botucatu Medical School Hospital (450 beds) during 2016–2017 after diagnosis of 1 or more HCAIs were enrolled. For each subject, we included 2 controls matched by specialty (for medical patients) or by the National Healthcare Safety Network (NHSN) surgical group. ⁸ The cohort was followed with weekly telephone calls for 24 weeks. Data recorded included (1) hospital readmissions; (2) return to work or usual daily activities (for those who did not work); (3) number of medicines taken after discharge; (4) number of medical consultations during follow up; (5) necessity of a caregiver (including family members).

Predictors of readmission and return to work or usual activities were assessed in univariate and multivariable Cox regression models. In addition to HCAIs, demographics, comorbidities (including the Charlson comorbidity index ⁹ ), and admission data (length-of-stay, procedures, devices) were tested as predictors in those models. We used a stepwise backward strategy for selection of variables in multivariable models. P values of .05 and .10 were set as limits for inclusion and exclusion of variables. Other outcomes were assessed using Mann-Whitney U and χ² tests, when appropriate.

We included 55 patients with HCAIs and 110 patients without HCAIs in the cohort. Among HCAI subjects, 20 had ≥2 infection sites. The overall distribution of sites was as follows: surgical site infection (SSI, n = 29); bloodstream infection (BSI, n = 20); pneumonia, (n = 11); urinary tract infection (UTI, n = 9); skin and soft-tissue infection (SST, n = 6).

Readmission during follow-up was reported for 39.3% of HCAI subjects and 18.2% of others (P=.003). In our multivariable analysis, HCAI (hazard ratio [HR], 4.84; 95% confidence interval [CI], 2.20–10.63; P<.001) and the Charlson comorbidity index (HR, 1.60; 95% CI, 1.13–2.25; P=.007) were significant predictors of readmission. On the other hand, HCAI was associated with later return to work or usual activities (HR, 0.30; 95% CI, 0.19–0.57; P < .001). Other significant associations for that outcome were surgery (HR, 1.83; 95% CI, 1.16–2.90; P = .01) and mechanical ventilation (HR, 0.53; 95% CI, 0.33–0.85; P = .009). Figure 1 presents survival graphics for the impact of HCAI on readmission and return to work or usual activities. Tables with detailed results of univariate and multivariable analyzes are available as supplementary files.

Fig. 1 Survival analysis graphics for hospital readmission and return to work or usual activities after discharge among subjects with and without healthcare-associated infections. (A) Survival graphic for hospital readmission (time counted in days). (B) Survival graphic for return to work or usual activities, with time counted in weeks. Note. HCAI, healthcare-associated infection.

The groups also differed in the following categories:

• ∙ Number of medicines taken after discharge: For HCAI, the median was 5 (quartiles [Q] 4 and 8), and for non-HCAI, the median was 4 (Q 2 and 6) (P = .02).

• ∙ Number of medical consultations during follow-up: For HCAI, the median was 6 (Q 2 and 10), and for non-HCAI, the median was 3 (Q 2 and 5) (P < .001).

• ∙ Number of consultations with nonmedical healthcare professionals during follow-up: For HCAI, the median was 1 (Q 0 and 2), and for non-HCAI, the median was 0 (Q 0 and 1) (P = 003).

Finally, 20.0% of subjects in the HCAI group required that a family member quit work (either definitively of temporarily) to be a caregiver, a situation reported by only 1 subject (0.9%) in the non-HCAI group (P < .001).

Our results agree with those of previous studies. Sreeramoju et al ³ identified HCAIs as a direct cause of hospital readmissions, while Emerson et al ⁴ (studying a very large retrospective cohort) found that subjects with infections caused by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile were more likely to be readmitted. Schor et al ⁵ reported that patients discharged after treating healthcare-associated pneumonia were 7.5 times more likely to be readmitted within 30 days of discharge than those treated for community-acquired pneumonia. Finally, Gohil et al ⁶ identified higher rates of infection-related readmissions among hospitals caring for populations with higher comorbidity and poverty rates.

However, our focus went beyond readmissions. We used return to work or usual activities as a proxy for patient autonomy and found that HCAIs had a significantly negative impact on that outcome. Other findings (eg, greater use of medicines and the number of medical and nonmedical consultations) were consistent with results from a study of the postdischarge impact of MRSA. ⁷

Our study was limited by the small number of subjects and the relatively short follow-up period. Also, we did not perform analysis of postdischarge healthcare costs of HCAI. However, our study also has strengths: the prospective design, the analysis of several relevant outcomes and the focus on all sites of infection. To our knowledge, this is the first study of postdischarge impact of HCAI conducted in a developing country. These countries face the paradox of having a greater burden of HCAI, and they have fewer resources to provide care to affected patients. ¹⁰

In conclusion, HCAI impacted hospital readmissions, later return to work or usual activities, greater use of medicines, and number of medical consultations. These are challenging areas for developing countries and reinforce the importance of including HCAI in the public health agenda.

Supplementary materials

To view supplementary material for this article, please visit https://doi.org/10.1017/ice.2018.201