A Naturalistic Study of the Effectiveness of Pharmacogenetic Testing to Guide Treatment in Psychiatric Patients With Mood and Anxiety Disorders.

OBJECTIVE: To examine the effectiveness of genetic testing in a real-world setting and to assess its impact on clinician treatment decisions. METHOD: This was a naturalistic, unblinded, prospective analysis of psychiatric patients and clinicians who utilized a commercially available genetic test (between April and October of 2013), which incorporates 10 genes related to pharmacokinetics and pharmacodynamics of psychiatric medications. Each patient's genetic results were provided to participating clinicians, who completed a baseline survey including patient medications, history, and severity of illness. Clinicians were prompted to complete surveys within 1 week of receiving the genetic results and again 3 months later. Patients likewise completed assessments of depression, anxiety, medication side effects, and quality of life at baseline, 1 month, and 3 months. RESULTS: Data from 685 patients were collected. Approximately 70% and 29% of patients had primary diagnoses of either a mood or anxiety disorder, respectively. Clinician-reported data, as measured by the Clinical Global Impressions-Improvement scale, indicated that 87% of patients showed clinically measurable improvement (rated as very much improved, much improved, or minimally improved), with 62% demonstrating clinically significant improvement. When analysis was restricted to the 69% of individuals with ≥ 2 prior treatment failures, 91% showed clinically measurable improvement. Patients also reported significant decreases in depression (P < .001), anxiety (P < .001), and medication side effects (P < .001) and increases in quality of life (P < .001). CONCLUSIONS: These results suggest that a substantial proportion of individuals receiving pharmacogenetic testing showed clinically significant improvements on multiple measures of symptoms, adverse effects, and quality of life over 3 months. In the absence of a treatment-as-usual comparator, the proportion of improvement attributable to the test cannot be estimated. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01507155.

Pharmacogenetic-guided psychiatric intervention associated with increased adherence and cost savings.

OBJECTIVES: Pharmacogenetic testing as a means of guiding treatment decisions is beginning to see wider clinical use in psychiatry. The utility of this genetic information as it pertains to clinical decision making, treatment effectiveness, cost savings, and patient perception has not been fully characterized. STUDY DESIGN: In this retrospective study, we examined health claims data in order to assess medication adherence rates and healthcare costs for psychiatric patients. METHODS: Individuals for whom pharmacogenetic testing was ordered (cases) were contrasted with those who did not undergo such testing (controls). Cases and controls were propensity score matched in order to minimize risk of confounding in this nonrandomized study. An initial analysis of 111 cases and 222 controls examined both adherence and healthcare costs. A replication study of 116 cases and 232 controls examined adherence alone, as cost data was not available for this latter cohort. RESULTS: Overall, individuals with assay-guided treatment were significantly more medication adherent (P = 1.56 3 10­3; Cohen's d = 0.511) than patients with standard treatment and demonstrated a relative cost savings of 9.5% in outpatient costs over a 4-month follow-up period, or $562 in total savings. CONCLUSIONS: The data show the utility of pharmacogenetic testing in everyday psychiatric clinical practice, as it can lead to improved patient adherence and decreased healthcare costs.

The potential utility of pharmacogenetic testing in psychiatry.

Over the last decade, pharmacogenetics has become increasingly significant to clinical practice. Psychiatric patients, in particular, may benefit from pharmacogenetic testing as many of the psychotropic medications prescribed in practice lead to varied response rates and a wide range of side effects. The use of pharmacogenetic testing can help tailor psychotropic treatment and inform personalized treatment plans with the highest likelihood of success. Recently, many studies have been published demonstrating improved patient outcomes and decreased healthcare costs for psychiatric patients who utilize genetic testing. This review will describe evidence supporting the clinical utility of genetic testing in psychiatry, present several case studies to demonstrate use in everyday practice, and explore current patient and clinician opinions of genetic testing.

Pharmacologic antagonism of the oral aversive taste-directed response to capsaicin in a mouse brief access taste aversion assay.

Chemosensory signaling by the tongue is a primary determinant of ingestive behavior and is mediated by specific interactions between tastant molecules and G protein-coupled and ion channel receptors. The functional relationship between tastant and receptor should be amenable to pharmacologic methods and manipulation. We have performed a pharmacologic characterization of the taste-directed licking of mice presented with solutions of capsaicin and other transient receptor potential vanilloid-1 (TRPV1) agonists using a brief access taste aversion assay. Dose-response functions for lick-rate suppression were established for capsaicin (EC(50) = 0.5 microM), piperine (EC(50) = 2 muM), and resiniferatoxin (EC(50) = 0.02 microM). Little or no effect on lick rate was observed in response to the full TRPV1 agonist olvanil. Capsaicin lick rates of wild-type and transient receptor potential melastatin-5 (TRPM5) knockout mice were equivalent, indicating that TRPM5, a critical component of aversive signaling for many bitter tastants, did not contribute to the capsaicin taste response. The selective TRPV1 antagonists N-(4-tertiarybutylphenyl)-4-(3-chloropyridin-2-yl)tetrahydropyrazine-1(2H)-carbox-amide (10 microM) and (E)-3-(4-t-butylphenyl)-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)acrylamide (AMG9810) (10 microM) effectively blocked capsaicin- and piperine-mediated lick suppression. However, (E)-3-(4-chlorophenyl)-N-(3-methoxyphenyl)-N-phenylprop-2-enamide (SB 366791) and capsazepine, also TRPV1 antagonists, were without effect at test concentrations of up to 30 and 100 microM, respectively. Our results demonstrate that TRPV1-mediated oral aversiveness presents a pharmacologic profile differing from what has been reported previously for TRPV1 pain signaling and, furthermore, that aversive tastes can be evaluated and controlled pharmacologically.

Quantitative assessment of TRPM5-dependent oral aversiveness of pharmaceuticals using a mouse brief-access taste aversion assay.

Many orally administered pharmaceuticals are regarded by humans as aversive, most often described as 'bitter'. Taste aversiveness often leads to patient noncompliance and reduced treatment effectiveness. 'Bitter' taste is mediated by T2R G-protein coupled receptors through a peripheral signaling pathway critically dependent upon function of the TRPM5 ion channel. The brief-access taste aversion (BATA) assay operationally defines aversive taste as suppression of the rate at which a rodent licks from sipper tubes that deliver tastant solutions or suspensions. We have used a mouse BATA assay for rapid quantification of oral aversiveness from a set of 20 active pharmaceutical ingredients (APIs). Robust lick-rate dose-response functions were obtained from both C57BL/6J wild type (WT) and C57BL/6J/TRPM5-/- (TRPM5 knockout) mouse strains, generating reliable determinations of potency and relative maximal oral aversiveness for each API. A subset of APIs was also evaluated in a human bitterness assessment test; effective concentrations for half-maximum responses (EC50s) from both the human test and WT mouse BATA were equivalent. Relative to WT potencies, EC50s from TRPM5 knockout mice were right-shifted more than 10-fold for most APIs. However, APIs were identified for which EC50s were essentially identical in both mouse strains, indicating a TRPM5-independent alternative aversive pathway. Our results suggest the BATA assay will facilitate formulation strategies and taste assessment of late development-phase APIs.

Long-term effect of cued fear conditioning on REM sleep microarchitecture in rats.

STUDY OBJECTIVES: To study long-term effects of conditioned fear on REM sleep (REMS) parameters in albino rats. DESIGN: We have investigated disturbances in sleep architecture, including muscle twitch density as REMS phasic activity, and freezing behavior in wakefulness, upon reexposure to a conditioned stimulus (CS) on Day 1 and Day 14 postconditioning. SUBJECTS: Male Sprague-Dawley rats prepared for polysomnographic recordings. INTERVENTIONS: After baseline sleep recording, the animals in the experimental group received five pairings of a 5-sec tone, co-terminating with a 1-sec, 1 mAfootshock. The control rats received similar numbers of tones and shocks, but explicitly unpaired. On postconditioning days, after reexposure to tones alone, sleep and freezing behavior were recorded. MEASUREMENTS AND RESULTS: Conditioned fear significantly altered REMS microarchitecture (characterized as sequential-REMS [seq-REMS: < or =3 min episode separation] and single-REMS [sin-REMS: >3 min episode separation]) on Day 14. The total amount and number of seq-REMS episodes decreased, while the total amount and number of sin-REMS episodes increased. Further, the CS induced significant increases in freezing and REMS myoclonic twitch density in the experimental group. Reexposure to the CS produced no alterations in controls. CONCLUSIONS: The results suggest that conditioned fear causes REMS alterations, including difficulty in initiating a REMS episode as indicated by the diminution in the number of seq-REMS episodes. Another finding, the increase in phasic activity, agrees with the inference from clinical investigations that retrieval of fearful memories can be associated with the long-term REMS disturbances characteristic of posttraumatic stress disorder.

Stress-induced changes in sleep in rodents: models and mechanisms.

Psychological stressors have a prominent effect on sleep in general, and rapid eye movement (REM) sleep in particular. Disruptions in sleep are a prominent feature, and potentially even the hallmark, of posttraumatic stress disorder (PTSD) (Ross, R.J., Ball, W.A., Sullivan, K., Caroff, S., 1989. Sleep disturbance as the hallmark of posttraumatic stress disorder. American Journal of Psychiatry 146, 697-707). Animal models are critical in understanding both the causes and potential treatments of psychiatric disorders. The current review describes a number of studies that have focused on the impact of stress on sleep in rodent models. The studies are also in Table 1, summarizing the effects of stress in 4-h blocks in both the light and dark phases. Although mild stress procedures have sometimes produced increases in REM sleep, more intense stressors appear to model the human condition by leading to disruptions in sleep, particularly REM sleep. We also discuss work conducted by our group and others looking at conditioning as a factor in the temporal extension of stress-related sleep disruptions. Finally, we attempt to describe the probable neural mechanisms of the sleep disruptions. A complete understanding of the neural correlates of stress-induced sleep alterations may lead to novel treatments for a variety of debilitating sleep disorders.

Centrally administered tumor necrosis factor-alpha facilitates the avoidance performance of Sprague-Dawley rats.

In addition to their immunological functions, recent research has indicated that the pro-inflammatory cytokines can influence learning and memory processes. We have previously shown that a peripheral injection of TNFalpha facilitates the acquisition of a leverpress avoidance task 24 h post-injection. Because the improved acquisition is presumably mediated by central changes, the current experiment involved directly injecting TNFalpha into the third ventricle 24 h prior to training. The data indicate that low (20 ng) but not high (40 ng) doses of TNFalpha produced improved avoidance performance. Results are discussed in terms of possible monoaminergic sensitization induced by TNFalpha and the relationship of this to acquisition of the avoidance response.

Corticotropin-releasing factor microinjection into the central nucleus of the amygdala alters REM sleep.

Psychological stressors have a prominent effect on rapid eye movement sleep (REMS) in humans and animals. We hypothesized that the stress-related neurochemical corticotropin-releasing factor (CRF), acting in the amygdala, could initiate neural events that lead to REMS alterations. Therefore, we made bilateral microinjections of three different doses of CRF into the central nucleus of the amygdala (CeA) in five rats. Only the lowest dose of CRF (1 ng) induced a change in sleep, specifically REMS, during the 4-h post-injection period. Thus, REMS alterations following psychological stress may depend, in part, on CRF release in the CeA.

Predator odor exposure facilitates acquisition of a leverpress avoidance response in rats.

We have previously reported that prior exposure to inescapable tailshock stress increased avoidance responding 24 hours later. We argued previously that this might model the avoidance behavior characteristic of post-traumatic stress disorder (PTSD). The current experiment was conducted to determine whether a more ethologically relevant stressor would produce similar effects on avoidance responding. Therefore, rats were restrained for 2 hours and exposed to trimethylthiazoline (TMT), a component of fox feces, restrained only, or served as home cage controls. Twenty-four hours later, subjects received a 4-hour escape-avoidance session. Animals exposed to TMT made more escape responses overall, and made more avoidance responses than the other two groups by the 4th hour of the session. Differences between the TMT-exposed animals and restraint alone could not be explained by differences in corticosterone (CORT) levels. Results are discussed in terms of the possible neural changes induced by TMT exposure and the relationship to the behavioral aspects of PTSD or acute stress.

REM sleep: a sensitive index of fear conditioning in rats.

To examine the influence of conditioned fear stimuli on sleep-wake states, we recorded sleep in Sprague-Dawley rats after exposure to tones previously paired with footshock. After habituation to a recording chamber and the recording procedure, a baseline sleep recording was obtained the next day. One day later, experimental animals were exposed to shock training designed to induce conditioned fear (FC), consisting of five tone-footshock pairings. The 5-s tones (conditioned stimuli; CS) co-terminated with 1-s footshocks (unconditioned stimuli; US). The next day sleep was recorded for 4 h in the recording chamber after presentation of five CSs alone. Sleep efficiency (total sleep time/recording period) and REM sleep (REM) and non-REM (NREM) measures were determined. While sleep efficiency was not significantly changed after CS presentation, the percentage of total sleep time spent in REM (REM percentage) was reduced in the FC animals. The reduction in REM percentage in the FC animals was due to a decrease in the number of REM bouts. In a separate experiment, we repeated the procedures, except the tones and shocks were presented in an explicitly unpaired (UP) fashion. The next day, presentation of the tones increased REM percentage in the UP group. Results are discussed in terms of the decreases in REM as a response to conditioned fear, and the relevance of these findings to the sleep changes seen in post-traumatic stress disorder (PTSD).

A rodent model of sleep disturbances in posttraumatic stress disorder: the role of context after fear conditioning.

BACKGROUND: A prominent sleep disturbance, likely including a disruption of rapid eye movement sleep (REMS) continuity, characterizes posttraumatic stress disorder (PTSD). We set out to develop a fear conditioning paradigm in rats that displays alterations in sleep architecture analogous to those in PTSD. METHODS: Baseline polysomnographic recordings of rats were performed in a neutral context to which the rats had been habituated for several days. Rats were then shock- or mock-trained in a distinctly different context, and their sleep was studied the following day in that context. A separate group of rats was shock-trained and studied in the neutral context on the following 2 days. RESULTS: Rats that slept in the neutral context exhibited a REMS-selective increase in sleep 24 hours after training and increases in REMS and non-REMS 48 hours after training. In contrast, rats that slept in the presence of situational reminders of the training context exhibited a REMS-selective decrease in sleep 24 hours later. Animals that were mock-trained showed no changes in sleep. CONCLUSIONS: Shock training induced days-long changes in sleep architecture that were disrupted when the animal was exposed to situational reminders of the training context.

Stress-induced increases in avoidance responding: an animal model of post-traumatic stress disorder behavior?

One prominent symptom of post-traumatic stress disorder (PTSD) is avoidance of stimuli reminiscent of the traumatic event. We attempted to study this aspect of PTSD in two experiments. Groups of rats received forty 3-s tailshocks, or served as home cage controls (HCC). Twenty-four hours later, all subjects received a 4-h session of leverpress escape/avoidance conditioning. In Experiment 1, shock periods in the absence of a response were 1 s; in Experiment 2 they were 30 s. No group differences were observed in Experiment 1. In Experiment 2, previously shocked animals made more avoidance responses and had a higher percent avoidance during the fourth hour of the session than controls. Further, previously shocked animals had a higher efficiency ratio (the percent of responses that were avoidances). No group differences were observed in leverpresses during the safety period (an index of anxiety) in either study. Results are discussed in terms of the effects of stress on avoidance behavior as a potential model for this important feature of PTSD.

Leverpress escape/avoidance training increases neurotrophin levels in rat brain.

In addition to their well-known role in neural development, the neurotrophins BDNF and NGF help mediate the plasticity that occurs in the brain to promote learning. Exposure to learning procedures often leads to increases in neurotrophins, while exposure to stress often results in decreases. It is unclear how the neurotrophins would respond to an aversive learning task. Therefore, BDNF and NGF content in the dorsal striatum, hippocampus, and basal forebrain was measured following discrete trial lever-press escape/avoidance conditioning. Conditioning significantly increased levels of both neurotrophins in hippocampus and basal forebrain, relative to home cage controls (HCC). Contrary to expectations, the dorsal striatum did not show any significant changes. However, significant correlations were observed between dorsal striatal neurotrophins and aspects of avoidance performance. This may indicate that the dorsal striatum is involved in the performance aspects of the task. Results are discussed in terms of the role of neurotrophins in the acquisition of new information, and the neural structures involved in different types of memory.

Proinflammatory cytokines differentially affect leverpress avoidance acquisition in rats.

Recent evidence indicates that the pro-inflammatory cytokines (PICs) can affect learning and memory processes. To examine the effect of the PICs on leverpress escape/avoidance conditioning, we injected male Sprague-Dawley rats with IL-1beta, IL-6 (both 3.0 microg/kg, i.p.), TNFalpha (6.0 microg/kg, i.p.) or vehicle, 24h before a single 4-h session of leverpress escape/avoidance conditioning. The TNFalpha-treated animals made more avoidance responses and fewer escape responses than controls during the last hour of the session. Further, both TNFalpha- and IL-1beta-treated animals had a higher percent avoidance than controls during the 4th hour of the session. None of the cytokines had an effect on the number of leverpresses during safety, a putative measure of anxiety. Results are discussed in terms of the differential central effects of the pro-inflammatory cytokines and the possible relationship to avoidance conditioning.

Sexual frequency and salivary immunoglobulin A (IgA).

112 college students reported the frequency of their sexual encounters and were divided into four categories: none, infrequent (less than once a week), frequent (one to two times per week), and very frequent (three or more times per week). Participants also described their overall sexual satisfaction. Saliva samples were collected and assayed for salivary immunoglobulin A (IgA). Individuals in the frequent group showed significantly higher levels of IgA than the other three groups, which were comparable. Data on length of relationship and sexual satisfaction were not related to the group differences.

Effect of petting a dog on immune system function.

The present study assessed the effect of petting a dog on secretory immunoglobulin A (IgA) levels. 55 college students were randomly assigned to either an experimental group or one of two control groups. Group 1 (n= 19) petted a live dog; Group 2 (n = 17) petted a stuffed dog, while Group 3 (n = 19) simply sat comfortably on a couch. Each participant was exposed to one of the three conditions for 18 min. Pre- and posttreatment saliva samples yielded a significant increase in IgA for Group 1 only. Participants were also asked to complete the Pet Attitude Scale of Templer, Salter, Dickey, Baldwin and Veleber. Scores on this scale correlated with IgA increases only for participants in Group 2 (petting a stuffed animal). Results are discussed in terms of the beneficial effects of pets on health in general, and immunity in particular.

Ethanol consumption improves avoidance learning in rats: role of deprivation interval.

Voluntary oral self-administration of ethanol in rats has been used to model ethanol consumption and abuse in human beings, with contradictory results. The purpose of the current study was to assess the effect of voluntary ethanol consumption on acquisition of a lever press escape/avoidance task in rats. Male Wistar rats were exposed to ethanol in a limited-access procedure, and either 1 day or 10 days after their last ethanol exposure, animals received a 4-h lever press escape/avoidance session. Control animals were not exposed to ethanol at any time. Animals in the 1-day ethanol-deprivation group performed significantly better than did the other two groups with respect to avoidance responding. There were no group differences in number of lever presses during a safety period, a measure of anxiety. Further, we obtained a significant negative correlation between behavioral performance and change in ethanol consumption after the escape/avoidance session, as well as a significant positive correlation between baseline ethanol consumption and avoidance performance. Results are discussed in terms of the potential neural mediators of the improved avoidance effect in animals in the 1-day ethanol-deprivation group.

Serum cholesterol levels and stressor controllability in rats.

Whether an organism can control a stressful event is often an important variable determining the impact of the event on physiology and behavior. Numerous behavioral and physiological variables are more adversely affected by uncontrollable stress. The present experiment with rat subjects compared the effect of controllable stress (escape conditioning) or uncontrollable stress (yoked control group) vs. home cage controls on total cholesterol, as well as high-density lipoprotein (HDL) and low/very-low density lipoprotein (LDL/VLDL) serum cholesterol. Results indicated that both stressed groups had higher total and LDL/VLDL cholesterol levels than home cage controls. No group differences were observed with HDL cholesterol. The escape and yoked control subjects did not differ from each other in any dependent measure. Results are discussed in terms of the probable mediators of stress-induced cholesterol increases, and the fact that these mediators may be insensitive to stressor controllability.

Low doses of interleukin-1beta improve the leverpress avoidance performance of Sprague-Dawley rats.

Recent research has indicated that the pro-inflammatory cytokines, particularly interleukin-1beta (IL-1beta), can affect learning and memory. We injected male Sprague-Dawley rats with IL-1beta (1.0, 3.0, or 6.0 microg/kg, i.p.) or saline vehicle, 24h before a single 4-h session of leverpress escape/avoidance conditioning. No effect of IL-1beta at any dose was observed in the number of escape responses across the 4-h session. However, subjects treated with the two lower doses (1.0 and 3.0 microg/kg) of IL-1beta performed more avoidance responses during the final hour of the 4-h session than the other two groups. Subjects treated with the highest dose of IL-1beta (6.0 microg/kg) did not differ from controls. Results are discussed in terms of the possible mechanisms behind the IL-1beta-induced enhancement of learning, as well as the observed dose-response relationship.