Association of recent incarceration with traumatic injury, substance use-related health consequences, and health care utilization

OBJECTIVE

The higher risk of death among recently released inmates relative to the general population may be because of the higher prevalence of substance dependence among inmates or an independent effect of incarceration. We explored the effects of recent incarceration on health outcomes that may be intermediate markers for mortality.

METHODS

Longitudinal multivariable regression analyses were conducted on interview data (baseline, 3-, 6-, and 12-month follow-up) from alcohol- and/or drug-dependent individuals (n = 553) participating in a randomized clinical trial to test the effectiveness of chronic disease management for substance dependence in primary care. The main independent variable was recent incarceration (spending ≥1 night in jail or prison in the past 3 months). The 3 main outcomes of this study were any traumatic injury, substance use-related health consequences, and health care utilization--defined as hospitalization (excluding addiction treatment or detoxification) and/or emergency department visit.

RESULTS

Recent incarceration was not significantly associated with traumatic injury (adjusted odds ratio [AOR] = 0.98; 95% confidence interval [CI]: 0.65-1.49) or health care utilization (AOR = 0.88; 95% CI: 0.64-1.20). However, recent incarceration was associated with higher odds for substance use-related health consequences (AOR = 1.42; 95% CI: 1.02-1.98).

CONCLUSIONS

Among people with alcohol and/or drug dependence, recent incarceration was significantly associated with substance use-related health consequences but not injury or health care utilization after adjustment for covariates. These findings suggest that substance use-related health consequences may be part of the explanation for the increased risk of death faced by former inmates.

New aspects of psychiatric morbidity in idiopathic environmental intolerances

OBJECTIVE

To understand idiopathic environmental intolerances (IEI)-formerly multiple chemical sensitivities (MCS)-it is helpful to outline its characteristic psychiatric morbidity.

METHOD

We applied a standardized interview according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (SCID) to 305 environmental patients with and without IEI.

RESULTS

Somatoform, affective and anxiety disorders were the most frequent diagnoses but only slightly differed between patients with or without IEI. In both groups, current substance-related disorders were rare. We found a clearly higher prevalence of psychotic, especially current delusional disorders, in IEI.

CONCLUSION

Somatization, depression, and anxiety are frequent in IEI but nonspecific. Psychotic disorders are more common in IEI than in other types of environmental illness. It appears worthwhile to study personality and cognitive style to explain the pivotal features of IEI.

Sensitization as a mechanism for multiple chemical sensitivity: relationship to evolutionary theory

Multiple chemical sensitivity (MCS) is a disorder in humans attributed to prior chemical exposure. Sensitization is an amplification of neuronal responsiveness that elicits increased behavioral responding to stimuli, and occurs in a recently developed rat model of MCS. Rats were exposed to repeated formaldehyde (Form) and their response in three behavioral tests, including locomotor activity after a cocaine challenge, conditioned fear, and behavioral avoidance of Form, was assessed. In all three tests, rats demonstrated sensitized behaviors, implicating amplified responding within specific limbic brain regions. Evolutionary theory in the context of MCS specifies how the behavioral strategies of those with MCS are consistent with the notion that their self-perceived sense of survival and reproductive fitness may be threatened by chemical exposures. This behavior may be mediated by the same limbic brain regions that become sensitized after repeated chemical exposure in animals.

Limbically Augmented Pain Syndrome (LAPS): Kindling, Corticolimbic Sensitization, and the Convergence of Affective and Sensory Symptoms in Chronic Pain Disorders

There is abundant clinical evidence that depression occurs with high frequency among chronic pain patients. When compared with other serious medical disorders, the prevalence of depression in chronic pain appears high. The fundamental reason for this association is unknown. Theories have attempted to explain the link between pain and depression in terms of psychologic mechanisms. Other theories highlight shared neurobiologic substrates. However, a comprehensive theory integrating biologic and psychologic viewpoints remains elusive. In this article, we draw on research on neuroplastic processes in corticolimbic structures to model the linkage between the sensory and affective domains of pain. Our hypothesis is based on kindling experiments in animals that elucidate the complex neurobiologic mechanisms that transduce exteroceptive and interoceptive stimuli into "memory" at the cellular/synaptic level. This experimental model has found application in the affective disorders to explain how a person's history of exposure to psychologic trauma configures the neurobiologic substrate for later-amplified pathologic response. In applying kindling research to pain, we begin by reviewing the literature on nociception-induced neuroplasticity at the corticolimbic level. We suggest that kindling and related models of neuroplasticity can be used to describe ways in which exposure to a noxious stimulus may, under certain conditions, lead to a sensitized corticolimbic state. This sensitized state can be described in terms of the kindling properties of amplification, spontaneity, neuroanatomic spreading, and cross-sensitization. A case example illustrates how these properties offer a neurobiologic framework for understanding the sensory/affective/behavioral symptom complex seen in a subset of chronic pain patients. These patients are characterized by atypical and treatment-refractory pain complaints, in association with disturbances of mood, sleep, energy, libido, memory/concentration, behavior, and stress intolerance. We introduce the term "limbically augmented pain syndrome" to describe this symptom complex.

Cocaine preexposure fails to sensitize the acquisition of cocaine-induced taste aversions

In two separate experiments, rats were given either an intraperitoneal (IP) injection of 10 mg/kg cocaine once a day for 10 consecutive days (Experiment 1) or a single IP injection of 40 mg/kg of cocaine (Experiment 2) prior to receiving repeated pairings of a novel saccharin solution with cocaine (32 mg/ kg; subcutaneous; SC). Although vehicle-preexposed subjects given saccharin-cocaine pairings readily acquired an aversion to the cocaine-associated saccharin solution, subjects preexposed to cocaine (whether 10 times or only once) displayed a retarded acquisition of the aversion. That is, cocaine preexposure attenuated the acquisition of cocaine-induced taste aversions. There was no difference in the degree of attenuation between the two preexposure conditions. Thus, under conditions that are effective in inducing sensitization within other behavioral preparations there was no evidence of sensitized cocaine-induced taste aversions. The results from the present investigation are similar to reports from this laboratory and others demonstrating that preexposure to cocaine, as with a range of other psychoactive drugs, results in weaker taste aversions. The basis for the attenuating effects of cocaine preexposure was discussed in terms of an adaptation to the aversive effects of cocaine.

Behavioral sensitization after repeated formaldehyde exposure in rats

Multiple chemical sensitivity (MCS) is a phenomenon whereby individuals report increased sensitivity to chemicals in the environment, and attribute their sensitivities to prior exposure to the same or often structurally unrelated chemicals. A leading hypothesis suggests that MCS is akin to behavioral sensitization observed in rodents after repeated exposure to drugs of abuse or environmental stressors. Sensitization occurring within limbic circuitry of the central nervous system (CNS) may explain the multisymptom complaints in individuals with MCS. The present studies represent the continuing development of an animal model for MCS, the basis of which is the CNS sensitization hypothesis. Three behaviors were assessed in rats repeatedly exposed to formaldehyde (Form) inhalation. In the first series of experiments, rats were given high-dose Form exposure (11 parts per million [ppm]; 1 h/day x 7 days) or low-dose Form exposure (1 ppm; either 1 h/day x 7 days or 1 h/day x 5 days/week x 4 weeks). Within a few days after discontinuing daily Form, cocaine-induced locomotor activity was elevated after high-dose Form or 20 days of low-dose Form inhalation. Approximately 1 month later, cocaine-induced locomotor activity remained significantly elevated in the 20-day Form-exposed rats. The second experiment assessed whether prior exposure to Form (20 days, as above) would alter the ability to condition to an odor (orange oil) paired with footshock. The results suggested a tendency to increase the conditioned fear response to the odor but not the context of the footshock box, and a decreased tendency to extinguish the conditioned fear response to odor. The third experiment examined whether CNS sensitization to daily cocaine or stress would alter subsequent avoidance responding to odor (Form). Daily cocaine significantly elevated approach responses to Form, while daily stress pretreatment produced a trend in the opposite direction, producing greater avoidance of Form. Preliminary studies indicated that repeated daily Form inhalation (20 days, as above) produced a greater avoidance to subsequent Form presentation, suggesting that daily Form inhalation may serve as a stressor. The results support the hypothesis that repeated chemical exposure in rats may produce CNS plasticity manifest as greater sensitivity to dopaminergic drugs, enhanced fear conditioning to odor paired with an aversive event, and greater avoidance of odors. Some of these behavioral changes observed in rats may provide a link with symptoms in a subset of individuals with MCS.

Evolutionary game theory and multiple chemical sensitivity

Newlin's [Newlin D.B. Evolutionary game theory of tolerance and sensitization in substance abuse. Paper presented to the Research Society on Alcoholism, Hilton Head, SC, 1998] evolutionary game theory of addictive behavior specifies how evolutionarily stable strategies for survival and reproduction may lead to addiction. The game theory of multiple chemical sensitivity (MCS) assumes that: (1) the MCS patient responds to low-level toxicants as stressors or as direct threats to their survival and reproductive fitness, (2) this activates the cortico-mesolimbic dopamine system, (3) this system is a survival motivation center--not a 'reward center', (4) the subject emits a counter-response that is in the same direction as the naive response to the chemicals, (5) previously neutral stimuli associated with chemicals also trigger conditioned responses that mimic those to the chemicals, (6) these counter-responses further activate the dopaminergic survival motivation system, and (7) this produces a positive feedback loop that leads to strong neural sensitization in these structures and in behavior controlled by this system, despite a small initial response. Psychologically, the MCS patient with a sensitized cortico-mesolimbic dopamine system is behaving as though his/her survival is directly threatened by these chemicals. Non-MCS subjects have counter-responses opposite in direction to those of the chemicals and show tolerance. An autoshaping/sign-tracking model of this game is discussed. This evolutionary game makes several specific, testable predictions about differences between MCS subjects, non-MCS controls, and substance abusers in laboratory experiments, and between sensitized and nonsensitized animals.