Depression and Anxiety as a Factor of Contact Precautions over Two Years in An Urban Tertiary Care Hospital

Background: Contact Precautions are generally reported to increase depression and anxiety in hospitalized patients. Previous studies have been limited by small sample size and narrow range of underlying conditions of included patients.

Objective: To estimate the association between contact precautions and depression/anxiety among all major medical/surgical service admissions over two years.  

                                      

Methods: All admissions (n=51,946) to major medical/surgical services during two years at an urban tertiary care hospital were queried from a well-validated relational database containing patients' administrative, pharmacy and laboratory data. Out of 51,946 admissions, 9,561 admissions were excluded due to use of antidepressants, and 1,202 were excluded due to drug or alcohol dependence.  In this study, Contact Precautions were defined as presence of an indicator for any multidrug-resistant bacteria. Outcomes were ICD-9 codes for anxiety and depression. Chi-squared, t-tests and logistic regression analyses were completed in SAS v9.1.

Results:   Among the 41,183 admission included in this study, 6,005 patients were on Contact Precautions. There were 5,537 ICD-9 codes for depression and 1,946 ICD-9 codes for anxiety. Patients placed on Contact Precautions had higher odds of having an ICD-9 code for depression (unadjusted odds ratio (OR): 1.34 CI: 1.24-1.44) than patients not placed on Contact Precautions. In contrast, Contact Precautions were associated with fewer ICD-9 codes for anxiety (OR: 0.86 95% confidence intervals (CI): 0.75-0.99).  Bivariate analyses showed many potential confounders. Age, gender, Charlson comorbidity score, ICU stay, previous admission to the hospital in the past year and length of stay were chosen for the final models based on biologic plausibility and/or statistical significance.

Adjusting for age, gender, Charlson comorbidity score, ICU stay, previous admission to the hospital in the past year and length of stay, the use of Contact Precautions was associated with higher odds of having an ICD-9 code for depression. (OR: 1.19 95% CI: 1.09-1.30). When adjusting for the same factors, the use of Contact Precautions was associated with lower odds of having an ICD-9 code for Anxiety (OR: 0.84 95% CI: 0.72-0.99). 

Conclusions: In a large administrative database, patients who were on Contact Precautions had more frequent diagnoses of depression and less frequent diagnoses of anxiety disorders. Depression appears to be more frequent in patients on Contact Precautions and merits further research.