Clinical and economic outcomes of Acinetobacter vis a vis non-Acinetobacter infections in an Indian teaching hospital.

CONTEXT: Acinetobacter infections are a major nosocomial infection causing epidemics of infection in the Intensive Care Units (ICU). AIMS: This study estimates the clinical and economic outcomes of Acinetobacter infections and compares them with those of non-Acinetobacter bacterial infections. SETTINGS AND
DESIGN: Prospective cross-sectional observational study carried out for 6 months in the medicine ICU of a tertiary care hospital.
MATERIALS AND METHODS: Patients were divided in two groups, one group with Acinetobacter infections and the other with non-Acinetobacter infections. The data was collected for infection, length of stay (LOS), mortality and cost along with patient demographics from the hospital records for analysis. STATISTICAL ANALYSIS USED: The data was analyzed using Statistical Package for the Social Sciences Version 15.0. The LOS and cost of treatment (COT) for the two groups were compared using the nonparametric Mann-Whitney U-test.
RESULTS: A total of 220 patients were studied out of which 91 had Acinetobacter infections. The median LOS was 20 days in Group-A and 12 days in Group-B (P < 0.0001). The median COT was INR 125,862 in Group-A and INR 68,228 in the Group-B (P < 0.0001). Mortality in Group-A and Group-B was 32.97 and 32.56 (P = 0.949) respectively.
CONCLUSION: The burden of Acinetobacter infections in ICUs is increasing with the increase in LOS and COT for the patients. The infection control team has to play a major role in reducing the rate of nosocomial infections.

INTRODUCTION

Nosocomial infections (NI) have repeatedly been associated with an increased length of hospital stay and resulting increased cost in hospitalized patients. One of the recurrent causative agents of NI is Acinetobacter species.[12] Acinetobacter infections are common in hospitalized patients. The additional cost of treatment (COT) of infections can be directly related to the increased length of stay (LOS) in critically ill patients.[3] The commonly caused infections by Acinetobacter species are pneumonia (community acquired and ventilator-associated), meningitis, catheter-related bloodstream infections, skin and soft tissue infections.[4] Acinetobacter infections in Intensive Care Unit (ICU) are posing high risk due to the emergence of progressive resistance to carbapenems.[25] Infections with Acinetobacter have been associated with mortality rates as high as 43%.[6] The growing antimicrobial resistance among Acinetobacter with strains emerging resistant to carbapenem antibiotics adds to the seriousness of the issue.[7] In the event of a carbapenem resistant Acinetobacter infection, colistin is the available option despite being expensive and having a higher risk of toxicity.[89] The assessment of the burden of Acinetobacter and non-Acinetobacter infections in terms of LOS, COT and mortality is vital for policy makers and physicians in making decisions related to Acinetobacter infections.

This study calculates the burden of Acinetobacter infections in terms of LOS, COT and mortality in an ICU of a teaching hospital from South India. There are very few studies on burden of Acinetobacter infections from India. The study on burden of this infection is useful in formulating policy for budget allocation and to form appropriate strategy for planning the treatment options in terms of LOS and COT. The economic impact of Acinetobacter infections would indicate the need of interventions from policy makers to make necessary changes to control the LOS, COT and mortality.

MATERIALS AND METHODS

This study was carried out prospectively in medical ICU of Kasturba Hospital (KH), Manipal, Karnataka, India. The duration of the study was 6 months. All patients diagnosed with bacterial infections confirmed with culture report were included in the study. Patients <18 years of age and patients with sterile culture reports were excluded from the study. Patients were divided into two groups, Group-A and Group-B. Group-A consisted of patients with Acinetobacter infections while Group-B consisted of patients infected with bacterial infections other than Acinetobacter species. The study protocol was approved by the Institutional Ethics Committee of KH.

Data was collected prospectively on the clinical parameters along with patient demographics, site of infection, LOS in the hospital, mortality, hospitalization cost for patients in both groups. Patients were monitored on a day to day basis and the data was documented from the patients’ files. The status of nosocomial infection was established according to the Center for Disease Control and Prevention definition of NI.[10] Charlson co-morbidity index was calculated for individual patients in both the groups. Bacterial infections were classified on the basis of site of infection, such as respiratory infections, blood and body fluid infections, urinary tract infections, catheter related infections and skin and soft-tissue infections.

The direct costs included the cost of hospitalization, cost of investigations, cost of consultation and cost of medication. The cost data was obtained from the Finance Department of KH and grouped under the above mentioned four categories.

The data was analyzed using Statistical Package for the Social Sciences version 15.0. The LOS and COT for the two groups were compared using the nonparametric Mann–Whitney U-test and significance was calculated for 95% confidence interval. The mortality data was compared using the Chi-square test for the two groups.

RESULTS

A total of 220 patients with confirmed bacterial infections were included in the study out of which 91 (41.36%) had Acinetobacter infection during their stay in the ICU. The remaining 129 (58.64%) patients with non-Acinetobacter bacterial infections were used as control.

The mean age of the subjects was 54 ± 16.24 years with 66.8% males and 33.2% females. The demographics of the patients are given in Table 1.

Table 1

Patient demographics, LOS and mortality

Respiratory tract infections were commonly associated with Acinetobacter species (81.31% in Group-A whereas 38.75% in Group-B) among all infections. Details of site of infection are given in Table 2.

Table 2

Site of infection for Acinetobacter with non-Acinetobacter infections

The median LOS was 20 days in the Group-A as compared to 12 days in the Group-B (P < 0.0001).

Median COT for the Group-A was 125,862 INR whereas that for the Group-B was 68,228 INR (P < 0.0001).

Insurance coverage was present in only 28.2% of all patients. In Group-A, the percentage of people having insurance was much lesser (15.38%) as compared to the other group where 29.45% patients were having insurance coverage.

DISCUSSION

Acinetobacter infections are a major nosocomial infection causing epidemics of infection in the ICUs. Acinetobacter commonly causes infections in the hospital settings but there are significant cases from the community as well.[11] In our study, the LOS was significantly higher for the patients in Acinetobacter group as compared to the patients with non-Acinetobacter infections [Table 1]. The LOS increases the COT of the patient by increasing the hospitalization cost. The LOS data for Acinetobacter infections is in line with the data reported in the literature from USA.[12] The high LOS in case of patients with Acinetobacter infections may be due to the reason that Acinetobacter needs prolonged therapy and is a difficult organism to eradicate.[7] It tends to cause recurrent infections and the complications and morbidities associated with Acinetobacter infections are high.[1314]

The COT and mortality are important concerns for developing countries as they pose an additional burden on the economy. NI worsen the scenario by increasing the COT and mortality.[15] In this study, we observed that the COT was substantially higher in case of patients with Acinetobacter infections as compared to the patients with non-Acinetobacter infections. The incremental costs of treatment in case of the Acinetobacter infections is due to the increased LOS and higher morbidities associated with the Acinetobacter infections.[1214] The high hospitalization cost in Acinetobacter patients can directly be related to the high LOS in that group. The significantly higher investigation costs are suggestive of the recurrent infections occurring in case of Acinetobacter infections [Table 3]. Medication costs increase with the increase in the resistance of the organism to be eradicated.[1617] The rise of multi-drug resistant strains in case of Acinetobacter infections will also lead to the use of high-end antibiotics such as colistin leading to the increased medication cost. More than 80% of the population in India does not avail any health insurance and pay for the treatment out-of-pocket.[18] The burden caused by the Acinetobacter infections have significant socioeconomic impact on families of such patients. The cost categories in COT indicate a towering cost for medicines in Acinetobacter infections. The burden of COT due to the Acinetobacter infections can be tackled with the help of effective screening programs for Acinetobacter.[19]

Table 3

Cost of treatment for Acinetobacter versus non-Acinetobacter infections

The major sites of infection in case of Acinetobacter infections are respiratory, bloodstream, skin and soft tissue, central line related and urinary tract.[20] The main site of infection was respiratory in Acinetobacter infections while patients in non-Acinetobacter group had almost equal blood stream infections and respiratory infections [Table 2]. Similar observation was made in the study by Jang et al. 2009 in Taiwan.[21] This observation can be supported by the fact that most of the patients in the first group were on ventilators and humidifiers were used which leads to higher respiratory infections in those patients.[22]

The mortality in the two groups showed no significant difference in contrast to the results in literature.[6] This might be attributed to the heterogeneous nature of the patients in the two groups. The situation is alarming for Acinetobacter infections which needs immediate attention. Infection control strategies could play an important role in the prevention of such infections as antibiotics have a little role to play due to the growing resistance.[23] Combination therapy with two synergistic antibiotics can be another option to look for in case of resistant infections like these.[24]

A high burden of cost and LOS of Acinetobacter infections in the ICU was established in this study. There is a need to control Acinetobacter infections and to decrease their resulting expenditure and morbidity for the patients. Effective implementations of the infection control policies would bring down episodes of Acinetobacter infections.

Financial support and sponsorship

UGC Junior Research Fellowship.

Conflicts of interest

There are no conflicts of interest.