The association of psychiatric comorbidity and use of the emergency department among persons with substance use disorders: an observational cohort study.

BACKGROUND: Psychiatric and substance use problems are commonly found to be contributing factors to frequent Emergency Department (ED) use, yet little research has focused on the association between substance use and psychiatric comorbidity. This study assesses the association of a psychiatric comorbidity on (ED) use among patients with substance use disorders (SUDs). METHODS: The study focuses on 6,865 patients who were diagnosed with SUDs in the ED of a large urban hospital in the southern United States from January 1994 - June 1998. Patients were grouped by type of substance use disorder. After examining frequency of visits by diagnosis, the sample was assigned to the following groups-alcohol dependence (ICD9 = 303), alcohol abuse (ICD9 = 305.0), cocaine dependence/abuse (ICD9 = 304.2, 305.6), and polysubstance/mixed use (ICD9 = 305.9). A patient was classified with psychiatric comorbidity if a psychiatric diagnosis appeared during any of the patient's visits. The following psychiatric diagnoses were included-schizophrenia/psychoses, bipolar disorder, depression, anxiety, and dementia (ICD-9 codes available upon request). RESULTS: Patients with SUDs and psychiatric comorbidity had significantly higher mean number of ER visits (mean = 5.2 SD = 8.7) than SUD patients without psychiatric comorbidity (mean = 2.5, SD = 3.7). In logistic regressions predicting several categorizations of heavier use of the ED (either 4+, 8+, 12+, 16+, or 20+ visits over the span of the study) SUD patients with psychiatric comorbidity had adjusted odds ratios of 3.0 to 5.6 (reference group = patients with SUDs but no psychiatric comorbidity). This association was found across all substance use diagnostic categories studied, with the strongest relationship observed among patients with cocaine disorders or alcohol dependence. CONCLUSION: The results provide further support for the notion that the ED could and should serve as an important identification site for cost-effective intervention.

Brain metabolite concentration ratios in vivo: multisite reproducibility by single-voxel 1H MR spectroscopy.

Ten normal subjects were scanned identically at three separate sites (Little Rock, Houston, and New Orleans) to evaluate the reproducibility of brain metabolite ratios in single-voxel (1)H point-resolved spectroscopy sequence (PRESS) magnetic resonance (MR) spectroscopy in vivo. All scans were processed by a single individual at a single site. Coefficients of variation of the measured metabolite ratios generally were in the range found for previous single-voxel, single-site reproducibility studies. No differences were found among the sites for ratios of N-acetylaspartate to creatine (NAA/Cr) or choline to Cr (Cho/Cr) in left thalamus by multivariate ANOVA. Metabolite ratios of Cr or Cho relative to local brain H(2)O did not vary among the sites. However, by multivariate ANOVA, NAA/H(2)O differed between Little Rock and New Orleans, but not between those sites and Houston. Intraclass correlation coefficients suggested reasonable reproducibility between Little Rock and New Orleans, but not between those sites and Houston.

Emergency department use of persons with comorbid psychiatric and substance abuse disorders.

STUDY OBJECTIVE: This study assesses the relationship between substance abuse comorbidity and emergency department use among patients with psychiatric disorders in a large academic medical center. METHODS: Data were obtained from an administrative database including every patient visit to the ED of a large, academically affiliated county hospital from January 1994 through June 1998. This study focuses on 12,212 patients who were given a diagnosis of a primary psychiatric disorder in the ED. Diagnoses, assigned during ED visits, were made according to the Diagnostic and Statistical Manual of Mental Disorders III-R or IV. RESULTS: Primary psychiatric patients with substance use comorbidity had a significantly higher mean number of ED visits across the span of the study (mean 5.2; SD 7.4) than primary psychiatric patients without substance use comorbidity (mean 2.8; SD 3.9). In multiple logistic regression analyses predicting several categorizations of heavier use of the ED (either 4+, 8+, 12+, 16+, or 20+ visits over the span of the study), psychiatric patients with a comorbid substance use disorder had adjusted odds ratios of 2.8 to 4.9 (reference group was defined as patients with a psychiatric disorder but no substance use disorder; models controlled for age, race, and sex). CONCLUSION: Substance use comorbidity among patients presenting to an ED with a psychiatric disorder is associated with substantially increased ED service use. Improved detection, referral, and treatment of substance use disorders in this population could result in decreased ED use and improved patient outcomes.