Risk of Incarceration Between Cohorts of Veterans With and Without Mental Illness Discharged From Inpatient Units

Summary statistics are provided in Tables 1 and 2 . Mean±SD age was 57.5±15.5 for the entire sample, 57.7±.08 for the nonincarcerated group, and 40.6±1.02 for the incarcerated group. Over the entire sample 38.5% were Caucasian, 7.6% were African American, 2.2% were Hispanic, and 51.7% were of unknown race. Because race is not a required field within the VA database, unknown race was kept as a category in order to avoid a loss of more than 50% of the sample in the data analysis. Among veterans whose race was identified, African Americans were significantly overrepresented in the incarcerated group. The nonincarcerated and incarcerated veterans did not differ in their extent of service-connected disability.

Because records were unduplicated by taking the first discharge in the study period, the largest proportion of the sample was discharged in 1993 (40.9%). The distribution of the sample across other years was 18.2% from 1994, 15.1% from 1995, 12.8% from 1996, and 13.0% from 1997. The rates of incarceration were quite low: .7% in the 1993 cohort, .8% in the 1994 cohort, .7% in the 1995 cohort, .4% in the 1996 cohort, and .3% in the 1997 cohort. Overall results of the chi square test indicated no statistically significant association between year of discharge cohort and risk of incarceration.

In bivariate analyses the incarcerated group was significantly more likely than the nonincarcerated group to have a psychiatric diagnosis. All psychiatric conditions were represented except for bipolar disorder, where incarceration was associated with a lower likelihood of the disorder ( Table 1 ). Similarly, bivariate analyses showed that incarcerated patients were significantly more likely to have a diagnosis of drug abuse, alcohol abuse, or co-occurring disorders.

Table 3 presents two logistic regression models of the risk of incarceration. Diagnostic histories of drug abuse, alcohol abuse, and major depression were significantly related to risk of incarceration in the full model. No other psychiatric diagnoses, demographic variables, or treatment history variables were associated with risk of incarceration. The reduced model had similar results. Neither year of discharge nor diagnosis of schizophrenia or co-occurring disorders was predictive of incarceration in either model. Inpatient substance abuse treatment in the previous six months was associated with an elevated risk of incarceration only in the reduced model.

This study examined the differences between VA patients with and without mental health treatment histories and their risk of incarceration. Our analysis of five annual cohorts included all veterans discharged from any medical, surgical, psychiatric, or substance abuse inpatient unit within the VA Connecticut Healthcare System between 1993 and 1997. Our analysis of this large regional sample suggests several conclusions. First, similar to some other studies ( 12, 17, 25 ), in this study, although mental illnesses were a significant factor in bivariate analyses, they were generally not independent risk factors for incarceration after adjustment for other factors, especially diagnoses of substance abuse or dependence. Of all the psychiatric disorders, only depression was associated with an increased risk of incarceration in multivariate analyses. The strongest predictors of incarceration in all analyses were diagnoses of alcohol and drug abuse and dependence, along with receipt of inpatient substance abuse care.

Despite the higher risk of incarceration among veterans with depression, severe and persistent mental illness as usually conceptualized (schizophrenia and bipolar disorder) was not predictive of incarceration in these data, after adjustment for potentially confounding factors. It has been suggested that untreated psychiatric symptoms, particularly psychotic symptoms, are an important risk factor for incarceration ( 20 ). In our data, however, the sample was limited to persons who received VA inpatient health care services. Thus the lack of an association may be explained by the ready access to treatment among these veterans, and as a result, fewer untreated symptoms. A recent meta-analysis failed to show a strong relationship between clinical factors and recidivism. Demographic characteristics, criminal history, and deviant lifestyles showed far more predictive value ( 26 ).

Prior studies have demonstrated a robust association between alcohol and drug abuse and incarceration among persons with severe mental illnesses ( 17, 18 ). Many studies have shown that there is a high prevalence of alcohol and drug abuse within incarcerated populations ( 3 ) and that alcohol and drug abuse is associated with numerous poor outcomes among those with schizophrenia, including involvement with the criminal justice system ( 15, 27 ). Indeed, many of the outpatient treatment programs that have garnered attention recently are specifically intended for offenders with mental illness and histories of treatment nonadherence, criminal justice involvement, and alcohol and drug abuse ( 19, 20, 21 ). Consequently, one might have expected those with co-occurring disorders to have the greatest risk of incarceration.

However, with our data, substance use disorders were the strongest and the only independent predictors of incarceration. There was no effect of co-occurring disorders on incarceration independent of the main effect of having a substance use disorder. These results are consistent with other studies that have demonstrated a high prevalence of substance use disorders among inmates without mental illness ( 28, 29 ). Whether persons with mental illness are arrested mostly on drug charges remains unknown; however, such a finding would suggest that offenders with mental illness share common risk factors with offenders without mental illness. Thus an open question is whether, in treated samples like ours, mental illness alone increases the likelihood of incarceration or if alcohol and drug abuse or dependence represents the overriding risk factor of incarceration among offenders with serious mental illness and those without. Because drug abuse is associated with numerous psychiatric comorbidities ( 30 ), the high prevalence of reported mental illnesses within correctional institutions could primarily reflect the risk imposed by alcohol and drug abuse rather than by schizophrenia and other serious mental illnesses.

Surprisingly, our results did not show an independent link between personality disorders (specifically, antisocial personality disorder) and incarceration. Given the expected association between antisocial personality disorder and illegal conduct, these results suggest that incarceration with these disorders may also be mediated by substance abuse and dependence, at least in treated populations. Alternatively, given the overall low prevalence of diagnosed personality disorders within our sample (2.1%), it is possible that personality disorders were underreported in this administrative data set. This assumption is buttressed by findings showing an association between childhood conduct problems and acts of serious violence among adults with schizophrenia ( 31, 32 ).

A common claim derived from the criminalization hypothesis of mental illness is that widespread closure of mental health beds has resulted in increased incarceration among persons with severe mental illness ( 33 ). Our study, however, does not appear to support this assertion. In 1996, 80% of the VA inpatient psychiatric beds were closed in Connecticut ( 24 ), a pattern that was repeated to a more modest degree over the next several years across the VA system nationally. A limited number of studies have demonstrated that these closures were not associated with increased incarceration, state hospital inpatient service use, suicide, or cost among veterans with mental illnesses ( 34, 35, 36 ). It has been hypothesized that the increased availability of outpatient services may account for the lack of increased inpatient demand across state systems and the absence of worse outcomes among veterans during this period of system change ( 35, 37 ). This study adds support to these findings, because there was no statistically significant change in the proportion of veterans incarcerated during the study period, even though the baseline cohort could have been expected to have the highest risk because no patients were excluded as a result of prior hospitalization. In contrast, the general population of Connecticut during the same period experienced a steady increase in incarceration rates ( 38 ).

Although persons with schizophrenia were overrepresented in the incarcerated sample on bivariate analysis, our results do not suggest that schizophrenia or other related severe mental illnesses were significant independent risk factors for incarceration. Instead, our results are consistent with criminological models suggesting that alcohol and drug abuse are largely responsible for incarceration risk ( 20, 26, 39 ). Programs designed to prevent incarceration of people with mental illness should perhaps focus on alcohol and drug abuse treatment as the central component in addition to management of the symptoms of the psychiatric disorder. Because drug abuse represents not only the pathological process of addiction but also an illegal behavior, interventions for persons in the criminal justice system with drug abuse and with or without mental illness optimally would be aimed at recidivism reduction ( 20, 40 ). Such models favor a conceptualization of alcohol and drug abuse as problematic behaviors instead of secondary products of mental illnesses and therefore invest in various methods of legal leverage to attain community tenure. Given the shared risk factors for incarceration among mentally ill and non-mentally ill offenders, these criminological models may prove fruitful in reducing incarceration among populations with severe mental illness.

Several limitations of this study require comment. The study was limited to patients hospitalized in the VA Connecticut health care system and thus includes an older male population with access to free health care services. It remains unknown whether our results can be generalized to other populations. Second, all sociodemographic and diagnostic measures were based on administrative data rather than primary surveys or structured diagnostic interviews. Third, our study lacked measures of symptomatology and severity of psychopathology. A distinctive strength of the study was the opportunity to link health system and criminal justice data.

The arrest and incarceration of persons with mental illness have garnered deserved public and professional concern. Such concerns have endured for the past 25 years, since the modern induction of the criminalization hypothesis by Abramson ( 41 ). Substance use disorders, as suggested by this study, may be the primary risk factors for incarceration. Thus unique conceptual models that explore recidivism factors outside of traditional mental illness symptoms might prove useful in that they take into account known predictive models used in correctional services. The hypothesis that reductions in inpatient mental health services have increased the risk of incarceration among people with mental illness was not confirmed by our findings. Services for offenders with mental illness should therefore focus on broader approaches that can reduce risk factors, such as drug abuse, unstable housing, and unemployment, which threaten community tenure and appear to be the most likely risk factors for incarceration by persons with mental illness.

The authors thank the Connecticut Department of Correction for its assistance in this project.

The authors report no competing interests.

Dr. Erickson, Dr. Rosenheck, and Dr. Desai are affiliated with the Department of Psychiatry, Yale University and VA Connecticut Healthcare System, 950 Campbell Ave., West Haven, CT 06516 (e-mail: [email protected]). Dr. Trestman and Dr. Ford are with the Department of Psychiatry, University of Connecticut Health Center, Farmington.