The Influence of Neighborhood Environment on Treatment Continuity and Rehospitalization in Dually Diagnosed Patients Discharged From Acute Inpatient Care

The present study is a retrospective analysis that utilized data extracted from the medical records of 380 patients who were diagnosed with comorbid mental health and substance use disorders and treated in an acute inpatient unit at Temple University Hospital—Episcopal Campus. The sampled records were from patients admitted between September 30, 2002, and December 31, 2003. The admission length of patients ranged from 3 to 13 days (mean=11.4 days). Diagnosis was established after a comprehensive intake interview was conducted by a psychiatrist using DSM-IV-TR criteria. Since medical chart data were used, we relied on normal hospital procedure for generating psychiatric diagnoses, and therefore the reliability and validity of the diagnoses are unknown. All patients 1) were seen by an attending psychiatrist and psychiatric resident upon admission as well as daily, 2) received daily individual and group psychotherapy, and 3) participated in 12-step groups. Upon discharge, patients were referred for ongoing outpatient mental health and drug treatment as clinically indicated. All patients were given a referral for outpatient 12-step programs in the community, in addition to individual psychotherapy. The network of possible outpatient placements in Philadelphia consisted of more than 100 facilities located throughout the city.

Inclusion criteria were a diagnosis of co-occurring disorders (at least one mental disorder and a substance use disorder) and a positive urine drug screen for prototypical illicit drugs upon admission. All patients were enrolled in Community Behavioral Health, which is the behavioral health management organization for all Medicaid recipients in Philadelphia County.

All procedures for gathering information from medical records during chart extraction were done in compliance with Health Insurance Portability and Accountability Act guidelines (31), and information collected and entered into the sampled patient database did not include any identifying items, such as a patient’s name, actual address, Social Security number, or birth date. Since patients’ residential location was of primary interest for the research, exact address information (i.e., street address number) was de-identified by adding or subtracting a random odd number between one and 10, which preserved approximate block location while not breaching confidentiality. Data were collected by a research assistant, with authorization by Temple University Hospital after the study was classified as exempt by the Temple University Institutional Review Board.

In general, the patients included in our sample represented a primarily poor, inner city, minority population, with the majority being active cocaine users (61%). Slightly less than one-half of the patients in the sample (43%) kept their initial outpatient appointment within 30 days of discharge from the acute inpatient unit, and approximately one-half (51%) were rehospitalized within 1 year. Table 2 details the demographic and clinical characteristics of the patients (mean age=38 years old; age range=18–67 years old), and descriptive data regarding neighborhood environment are reported in Table 3 .

Results of the stepwise-forward regression analyses for outcome variables (whether a patient kept his or her appointment within 30 days of discharge [“KEPT”]; whether a patient was readmitted within 1 year following his or her index admission date [“READMIT”]) are reported in Table 4 .

For the outcome variable pertaining to whether a patient kept his or her appointment within 1 year following his or her index admission date, model 1 contained the results of a stepwise-forward regression in which the geographic variables were excluded and only the individual-level variables were allowed to enter the regression equation. Results indicated that the chief complaint of “bizarre behavior” (i.e., grossly inappropriate behavior) was the only significant individual-level variable. None of the other individual-level variables explained a significant portion of the variance in the outcome to be included in the model once we accounted for the influence of bizarre behavior. Model 2 contained the results of a stepwise-forward regression in which the individual variables were excluded and only the geographic variables were allowed to enter the equation. Results revealed that patients were less likely to keep their appointments if they lived in areas with relatively high rates of vacant housing and areas relatively far from an Alcoholics Anonymous meeting location. Additionally, returning home following discharge (versus returning to residential treatment or a boarding home, halfway house, or recovery house) decreased the likelihood of treatment continuity. When both individual and geographic characteristics were allowed to enter the stepwise regression of the outcome variable pertaining to whether a patient kept his or her appointment within 1 year following his or her index admission date (model 3), all independent variables that were significant in models 1 and 2 remained significant, with approximately the same odds ratios and significance values. The following additional individual-level variable emerged as significant in this context: whether a patient had a positive urinary drug screen for opioids. Patients with this characteristic were less likely to attend their first treatment appointment within 30 days of discharge. It is pertinent to note that the classification accuracy of model 3 was higher than that for both models 1 and 2, although it exhibited only marginal improvement over model 2. The area under the curve was also higher for model 3 than for the other two models and was highly significant. The magnitude of the odds ratio for patients who kept their postdischarge treatment appointment is illustrated in Figure 2 .

For the outcome variable pertaining to whether a patient was readmitted to the hospital within 1 year following his or her index admission date, models 1, 2, and 3 also show results for stepwise forward regression analyses of individual variables only, geographic variables only, and individual and geographic variables combined, respectively ( Table 5 ). Model 1 indicated that being Hispanic and having a previous admission to the psychiatric emergency room both increased the likelihood of being readmitted within 1 year, with the presence of a previous emergency room admission increasing the likelihood by nearly 600%. However, having a chief complaint of depression decreased the likelihood of being readmitted within 1 year (odds ratio=0.62, p<0.05). Two geographic variables emerged in model 2 as being significantly related to the outcome variable of being readmitted within 1 year: distance from a patient’s postdischarge location to the nearest Narcotics Anonymous meeting place and the percentage of people with a high school diploma residing in the block group of a patient’s postdischarge location. The likelihood of being readmitted within 1 year was increased if a patient was discharged after hospitalization to a location near a Narcotics Anonymous meeting place and in an area with low educational attainment. For model 3, in which all individual and geographic variables were combined, all independent variables present in models 1 and 2 remained in the model, with approximately the same odds ratios and significance values. The exception was the presence of the chief complaint of depression, which was present in model 1 but was not entered into the equation in model 3. Classification accuracy and the area under the curve showed that models 1 and 3 were largely equivalent in predictive power, being both highly significant and more accurate than model 2. Model 3 also included the outcome variable of treatment continuity and the geographic variable of the distance from a subject’s postdischarge location to the hospital in order to determine whether treatment continuity or proximity to the hospital influenced the likelihood of readmission within 1 year. However, neither variable contributed to the explanation of the variance in the outcome once we accounted for the influence of the other variables.

The present study employed a geographic information system as a tool to determine the predictive value of various geographic factors in patients’ neighborhood environment, such as the proximity to bars, deli outlets selling beer, and Alcoholics Anonymous meeting places as well as crime, vacant housing, and various other features, that might influence an individual to adhere to their first outpatient psychiatric appointment within 30 days postdischarge or to experience rehospitalization within 1 year following discharge. The present research is consistent with that of Drake et al. (29), who advocated for greater focus on environmental context in future intervention research to better address the long-term needs of dually diagnosed patients. Our results are also consistent with a small but newly emerging body of literature identifying various types of neighborhood factors associated with various negative mental health and substance abuse outcomes (11, 15 –, 19, 22, 39) .

In the present study, the chief complaint of bizarre behavior (i.e., grossly inappropriate behavior) and a patient returning home following hospital discharge (versus returning to an institutional setting) were both found to reduce the likelihood of treatment continuity. As we suggested in previous research (2), some individuals may seek initial hospitalization as a result of acute conflicts in their lives, for drug detoxification, or as a temporary respite from life on the streets. For these patients, continuing in outpatient treatment after discharge from the hospital may be of less importance than it is for those patients seeking relief from longer-term, chronic psychiatric illnesses. In the present study, patients who used heroin were less likely to attend outpatient treatment. This could be reflective of the nature of opioid addiction, in which outpatient treatment may be perceived as having less value than other types of modalities, such as residential and methadone maintenance therapy. Residing in an area with a high degree of vacant housing reduced the likelihood of a patient attending initial outpatient treatment. This variable most likely relates to the general quality of a neighborhood’s social disorganization. Indeed, a number of studies have identified neighborhood social disorganization as a factor associated with various negative mental health and substance abuse outcomes (e.g., 15, 16, 22) . Patients who lived farther from an Alcoholics Anonymous meeting place were also less likely to attend their first postdischarge treatment appointment. This is, perhaps, because meeting locations appear to be predominantly located in nonminority, working or middle class neighborhoods or in center city/business districts, which are often not easily accessible for the patients assessed in our study.

In terms of rehospitalization, Hispanic patients had an increased likelihood of readmission within 1 year after discharge. Because our hospital is located in a Hispanic neighborhood, we theorized that proximity to the hospital would increase the likelihood of readmission. However, we examined whether the distance from a patient’s home to the hospital predicted rehospitalization and found that this variable was not significant. Close proximity to Narcotics Anonymous meeting places also increased the likelihood of readmission. An examination of the spatial distribution of Narcotics Anonymous meeting places in Philadelphia suggested that, in contrast to Alcoholics Anonymous meeting locations, Narcotics Anonymous meetings are located in areas where there are concentrations of drug users and are significantly correlated with drug sale density.

There are several limitations to the present study. The data were extracted from hospital charts and therefore may be less accurate than prospective, more highly controlled research studies. Additionally, the study was conducted in a single hospital in a limited geographic area. Further, it is possible for patients to have been readmitted to hospitals other than Temple University Hospital and therefore not be part of our data set. There are three other crisis response centers in Philadelphia, with Temple University Hospital receiving the greatest number of patients. The clinicians affiliated with the present study reported that most of their patients do tend to return to Temple University Hospital’s acute inpatient unit when rehospitalized, but this has not been verified empirically.

The present results, although preliminary, yield potentially important clinical implications for psychiatric populations. What is important is not so much the influence of the specific geographic variables that affected treatment continuity and rehospitalization, but rather that these findings should be viewed as evidence for the importance of further investigating the role of neighborhood context in psychiatric treatment and hospital aftercare planning. Currently, hospital discharge planning treatment staff rarely take into account the overall quality of a patient’s neighborhood or proximity to certain environmental features that might trigger relapse and rehospitalization. Patients are often influenced by the environment in which they live, and therefore we believe that the environmental contingencies, inherent in communities and neighborhoods, affecting individual behavior are robust concepts, which apply across the different geographic contexts of cities, nations, and cultures. A more explicit focus on an individual’s neighborhood and community context represents an important but understudied area in psychiatry, in terms of both research and clinical practice, which can potentially enhance long-term care and treatment planning for psychiatric patients. Additional collaborative work with experts in geographic information science is warranted to better understand the role of the neighborhood environment in predicting important clinical outcomes.

Received Nov. 11, 2008; revision received May 22, 2009; accepted June 22, 2009 (doi: 10.1176/appi.ajp.2009.08111667). From the Department of Geography and Urban Studies, Temple University, Philadelphia; Department of Psychiatry and Behavioral Sciences, Temple University, Episcopal Campus, Philadelphia. Address correspondence and reprint requests to Dr. Stahler, Department of Geography and Urban Studies, 309 Gladfelter Hall, Temple University (025-27), Philadelphia, PA 19122; [email protected] (e-mail).

Dr. Baron consults as a disease-state visiting professor for Eli Lilly and the California Academy of Family Practice; and he participates on the data monitoring bards of ACI Pharma and Pfizer. Drs. Stahler and Mennis and Ms. Cotlar report no financial relationships with commercial interests.

Supported in part by grants from the Temple University Institute for Policy Affairs, Temple University College of Liberal Arts (CLA) Research Incentive Fund, and Temple University College of Liberal Arts Mid-Career Fellowship Award.