Guidelines for the recording and evaluation of pharmaco-sleep studies in man: the International Pharmaco-EEG Society (IPEG).

The International Pharmaco-EEG Society (IPEG) presents guidelines summarising the requirements for the recording and computerised evaluation of pharmaco-sleep data in man. Over the past years, technical and data-processing methods have advanced steadily, thus enhancing data quality and expanding the palette of sleep assessment tools that can be used to investigate the activity of drugs on the central nervous system (CNS), determine the time course of effects and pharmacodynamic properties of novel therapeutics, hence enabling the study of the pharmacokinetic/pharmacodynamic relationship, and evaluate the CNS penetration or toxicity of compounds. However, despite the presence of robust guidelines on the scoring of polysomnography -recordings, a review of the literature reveals inconsistent -aspects in the operating procedures from one study to another. While this fact does not invalidate results, the lack of standardisation constitutes a regrettable shortcoming, especially in the context of drug development programmes. The present guidelines are intended to assist investigators, who are using pharmaco-sleep measures in clinical research, in an effort to provide clear and concise recommendations and thereby to standardise methodology and facilitate comparability of data across laboratories.

Somno-Art Software identifies pathology-induced changes in sleep parameters similarly to polysomnography.

Polysomnographic sleep architecture parameters are commonly used to diagnose or evaluate treatment of sleep disorders. Polysomnography (PSG) having practical constraints, the development of wearable devices and algorithms to monitor and stage sleep is rising. Beside pure validation studies, it is necessary for a clinician to ensure that the conclusions drawn with a new generation wearable sleep scoring device are consistent to the ones of gold standard PSG, leading to similar interpretation and diagnosis. This paper reports on the performance of Somno-Art Software for the detection of differences in sleep parameters between patients suffering from obstructive sleep apnea (OSA), insomniac or major depressive disorder (MDD) compared to healthy subjects. On 244 subjects (n = 26 healthy, n = 28 OSA, n = 66 insomniacs, n = 124 MDD), sleep staging was obtained from PSG and Somno-Art analysis on synchronized electrocardiogram and actimetry signals. Mixed model analysis of variance was performed for each sleep parameter. Possible differences in sleep parameters were further assessed with Mann-Whitney U-test between the healthy subjects and each pathology group. All sleep parameters, except N1+N2, showed significant differences between the healthy and the pathology group. No significant differences were observed between Somno-Art Software and PSG, except a 3.6±2.2 min overestimation of REM sleep. No significant interaction 'group'*'technology' was observed, suggesting that the differences in pathologies are independent of the technology used. Overall, comparable differences between healthy subjects and pathology groups were observed when using Somno-Art Software or polysomnography. Somno-Art proposes an interesting valid tool as an aid for diagnosis and treatment follow-up in ambulatory settings.

Validation of Somno-Art Software, a novel approach of sleep staging, compared with polysomnography in disturbed sleep profiles.

Study Objectives: Integrated analysis of heart rate (electrocardiogram [ECG]) and body movements (actimetry) during sleep in healthy subjects have previously been shown to generate similar evaluation of sleep architecture and continuity with Somno-Art Software compared to polysomnography (PSG), the gold standard. However, the performance of this new approach of sleep staging has not yet been evaluated on patients with disturbed sleep. Methods: Sleep staging from 458 sleep recordings from multiple studies comprising healthy and patient population (obstructive sleep apnea [OSA], insomnia, major depressive disorder [MDD]) was obtained from PSG visual scoring using the American Academy of Sleep Medicine rules and from Somno-Art Software analysis on synchronized ECG and actimetry. Results: Inter-rater reliability (IRR), evaluated with 95% absolute agreement intra-class correlation coefficient, was rated as "excellent" (ICCAAAvg95% ≥ 0.75) or "good" (ICCAAAvg95% ≥ 0.60) for all sleep parameters assessed, except non-REM (NREM) and N3 sleep in healthy participants (ICCAAAvg95% = 0.43, ICCAAAvg95% = 0.56) and N3 sleep in OSA patients (ICCAAAvg95% = 0.59) rated as "fair" IRR. Overall sensitivity, specificity, accuracy, and Cohen's kappa coefficient of agreement (κ) on the entire sample were respectively of 93.3%, 69.5%, 87.8%, and 0.65 for wake/sleep classification and accuracy and κ were of 68.5% and 0.55 for W/N1+N2/N3/rapid eye movement (REM) classification. These performances were similar in healthy and patient population. Conclusions: The present results suggest that Somno-Art can be a valid sleep-staging tool in both healthy subjects and patients with OSA, insomnia, or MDD. It could complement existing non-attended techniques measuring sleep-related breathing patterns or be a useful alternative to laboratory-based PSG when this latter is not available.

Performance of Somno-Art Software compared to polysomnography interscorer variability: A multi-center study.

The visual scoring of gold standard polysomnography (PSG) is known to present inter- and intra-scorer variability. Previously, Somno-Art Software, a cardiac based sleep scoring algorithm, has been validated in comparison to 2 expert visual PSG scorers. The goal of this research is to evaluate the performances of the algorithm against a pool of scorers. Sixty PSG and actimetry recording nights, representative of clinical practice (healthy subjects and patients suffering from obstructive sleep apnea [OSA], insomnia or major depressive disorder), were scored by 5 different sleep scoring centers and by the Somno-Art Software. Intra-class correlation coefficient (ICC) and Wilcoxon Signed-Rank Test were calculated between each scorer and the average value of the 6 scorers, including Somno-Art Software. In addition, epoch-by-epoch agreement between scorers were analyzed. Somno-Art Software estimation of sleep efficiency, wake, N1+N2, N3 and REM sleep fit within the interscorer range for the full dataset and the subgroups, except for underestimating N3 sleep in OSA patients. Additionally, Somno-Art Software overestimated sleep latency compared to the average scoring for insomniacs (+4.7 ± 1.6min). On the full dataset, Somno-Art Software had good (0.75 < ICC<0.90) or excellent (ICC>0.90) ICC scores for all sleep parameters except N3 sleep (moderate score, 0.50 < ICC<0.75). For the 4-stages epoch-by-epoch agreement, Somno-Art Software was slightly below that of the visual scorers except for the healthy sub-group where an overlap was demonstrated. Somno-Art Software sleep scoring shows a good interscorer reliability in the range of the 5 visual polysomnography scorers.

Pharmacokinetic profile of SKP-1041, a modified release formulation of zaleplon.

OBJECTIVES: Two investigations aimed to define the pharmacokinetic profile of a modified-release preparation of zaleplon (SKP-1041). METHODS: Protocol SOM001 was a 5-way crossover, double-blind, randomized trial comparing three novel modified-release formulations of zaleplon 15 mg (SKP-1041A, SKP-1041B, SKP-1041C) to placebo and immediate-release zaleplon 10 mg. Protocol SOM002 was a randomized, crossover, open-label trial to compare the pharmacokinetics of SKP-1041B after day and night administration. In SOM001, study drug was administered at 9:00 a.m. (fasted); blood samples were obtained beginning 1 h predose through 12 h postdose. In study SOM002, study drug was administered at 9:00 a.m. or 10:30 p.m.; blood samples were obtained beginning 1 h predose through 12 h postdose. Subjects were 19 (SOM001) and 23 (SOM002) healthy adults between ages 20-46. RESULTS: Dose-normalized total AUCs for modified-release preparations A, B, C and immediate-release zaleplon were not significantly different; peak plasma concentrations were similar for A and B, and both were significantly higher than C. Time to peak plasma concentration for A, B, and C were 4-5 h compared to 1.5 h for immediate-release zaleplon; mean terminal phase half-life was in the range 1-2 h for A, B and immediate-release zaleplon. No significant differences were noted between day and night administration in the SOM002 study. CONCLUSIONS: Zaleplon, 15 mg, in a novel, modified-release formulation (SKP-1041) had a time to peak plasma concentrations at 4-5 h postdose compared to 1.5 h for immediate-release zaleplon, 10 mg. The pharmacokinetic profile suggests this formulation may be useful for treating middle-of-the-night awakening.

Citalopram may reduce sympathoadrenal hyperactivity in elderly depressed patients: an open multicenter study in Belgium and Luxembourg.

INTRODUCTION: Through effects of catecholamines upon the heart, blood vessels and platelets, sympathoadrenal hyperactivity contributes to the development of cardiovascular diseases in elderly depressed patients. To assess the cardiovascular effect of Citalopram in elderly depressed patients, data from an open multicenter study in Belgium and Luxembourg, in which a total of 811 patients were evaluated, was retrospectively analysed. Although the aim of the study was to assess the efficacy and safety of Citalopram, blood pressure and heart rate were also monitored. SUBJECT AND METHODS: Patients included in the study were referred either by psychiatrists, geriatricians or general practitioners. Clinical assessment included ratings on the Hamilton Rating Depression Scale, the Clinical Global Impression Scale, the UKU Side effect rating scale and the assessment of side effects spontaneously reported. RESULTS: With few side effects, Citalopram significantly improves the clinical condition of elderly patients suffering from depressive symptoms. A series of repeated multivariate analyses of covariance were performed on heart rate and blood pressure controlling for the effect of age. Interestingly, a sustained decrease of these parameters was shown during the whole study period reaching significance for systolic blood pressure (p<0.05). These effects were observed both in responding as well as non-responding patients, and were somewhat more marked in responders for heart rate (p=0.058). CONCLUSION: The slight but significant decrease in systolic blood pressure and heart rate suggests that citalopram may reduce sympathoadrenal hyperactivity and the related increased cardiovascular morbidity and mortality associated with depression.

Relationships between the number of ultradian cycles and key sleep variables in outpatients with major depressive disorder.

The regulation of the alternation between rapid eye movement sleep (REMS) and non-rapid eye movement sleep (NREMS) is still a matter of much debate. It is also an important topic for psychiatric research, since both sleep components show anomalies in Major Depressive Disorders (MDD) and related syndromes. In previous studies on healthy controls, we showed preferential links of the number of ultradian cycles with REMS-related variables rather than with NREMS-related variables. REMS Latency (RL), for example, was shown to be inversely related to the number of cycles. The present study replicates these analyses in a group of 29 patients with MDD (age range: 23-56; 16 females), after two adaptation nights. Results showed significant correlations between the number of cycles and REMS, and between the number of cycles and RL, whereas correlations with NREMS were not significant. This indirectly supports regulation hypotheses considering REMS as the main focus of the oscillation, inhibiting and interrupting NREMS. Also, when the RL is shorter, there are more ultradian cycles than when the RL is long. This adds an interesting element in the elucidation of the physiological meaning of anomalies of RL.

Suicidality in opioid-dependent subjects.

We determined suicide attempt characteristics in 160 opioid-dependent subjects. Three aspects of suicide vulnerability were also examined: familial aggregation of suicidal behaviors, degree of aggression/impulsivity, and smoking. Forty-eight percent of subjects had a personal history of suicide attempt. A personal history of suicide attempt was associated with an early onset of heroin use, but not with gender differences. A family history of suicide was a progressive risk factor for suicide attempt. Subjects with a personal history of suicide attempt had a higher degree of aggression/impulsivity and smoked more cigarettes. In conclusion, opioid-dependent subjects who attempt suicide show familial aggregation and clinical expressions of suicidal liability similar to those described in other psychiatric groups.

Effect of short-term treatment with gaboxadol on sleep maintenance and initiation in patients with primary insomnia.

STUDY OBJECTIVE: To perform an early evaluation of the efficacy and safety of gaboxadol in the treatment of primary insomnia. METHODS: 26 adults (18-65 years) with DSM-IV criteria for primary insomnia were randomly assigned gaboxadol (5 mg, 15 mg) or placebo in a double-blind, crossover study. After a 3-night polysomnographic (PSG) screen, treatment was administered 30 min before bedtime on 2 consecutive nights during 3 separate sessions including PSG. Efficacy analyses (n = 23) were based on the average of Nights 1 and 2, and compared gaboxadol versus placebo. Baseline was the average of Nights 2 and 3 of the screening session. Both gaboxadol doses significantly (P < 0.05) improved mean total sleep time (mean +/- SD: baseline = 368.0 +/- 51.1 min, 15 mg = 420.3 +/- 24.5 min, 5 mg = 419.8 +/- 20.4 min, placebo = 408.7 +/- 30.4 min). Both gaboxadol doses reduced mean wake after sleep onset, although statistical significance was only achieved with 5 mg (baseline = 61.6 +/- 35.4 min, 15 mg = 38.0 +/- 21.1 min, 5 mg = 34.6 +/- 14.3 min, placebo = 43.4 +/- 22.9 min). Gaboxadol 15 mg also significantly reduced mean latency to persistent sleep (baseline = 55.6 +/- 27.0 min, 15 mg = 23.6 +/- 15.1 min, placebo = 30.0 +/- 19.1 min) and enhanced slow wave duration (baseline = 72.4 +/- 20.8 min, 15 mg = 114.0 +/- 37.5 min, placebo = 93.9 +/- 31.3 min) with no significant effects on REM sleep duration. Patient reports (Leeds Sleep Evaluation Questionnaire) of reduced time to sleep and increased sleep quality showed significant improvement with gaboxadol 15 mg. No next-day residual effects were observed with either dose of gaboxadol (assessed 2 h and 9 h after lights on). All adverse events were mild or moderate. CONCLUSION: Gaboxadol 15 mg was effective and generally well tolerated in the short-term treatment of patients with primary insomnia. Gaboxadol also enhanced slow wave sleep duration and had no significant effects on REM sleep duration. These findings suggest that gaboxadol may be a useful treatment for insomnia.

A double-blind, placebo-controlled, randomized study evaluating the effect of paliperidone extended-release tablets on sleep architecture in patients with schizophrenia.

The effects of paliperidone extended-release on sleep architecture in patients with schizophrenia-related insomnia were evaluated in this multicenter, double-blind, randomized, placebo-controlled study. Patients received paliperidone extended-release 9 mg/day or matching placebo during the 14-day double-blind phase. Sleep architecture and sleep continuity were evaluated using polysomnograms. Subjective sleep measures were evaluated daily using the Leeds Sleep Evaluation Questionnaire. Efficacy and safety were also assessed. Thirty-six patients (17 on paliperidone extended-release, 19 on placebo; mean age 32.2 years) completed the study. Paliperidone extended-release treatment vs. placebo resulted in clinically and statistically significant differences in sleep measurements from baseline to endpoint including a reduction in: persistent sleep latency (41 min), sleep onset latency (35 min), number of awakenings after sleep onset (7), time awake in bed (50 min), and stage 1 sleep duration (12 min); prolongation in: total sleep time (53 min), sleep period time (42 min), stage 2 sleep duration (51 min), and rapid eye movement sleep duration (18 min); and an increase in sleep efficiency index (11%). Paliperidone extended-release, compared with placebo, did not exacerbate daytime somnolence and improved symptoms of schizophrenia. Paliperidone extended-release was well tolerated and improved sleep architecture and sleep continuity in patients diagnosed with schizophrenia and concomitant insomnia.

Surrogate outcomes in neurology, psychiatry, and psychopharmacology.

A surrogate outcome can be defined as an outcome that can be observed sooner, at lower cost, or less invasively than the true outcome, and that enables valid inferences about the effect of intervention on the true outcome. There is increasing interest in the use of surrogate outcomes of treatment efficacy measurement in investigational drug trials. However, the significance of surrogate markers of treatment outcome in neurology and psychiatry has not yet been sufficiently demonstrated. Few such markers have been adequately "validated, " that is, shown to predict the effect of the treatment on the clinical outcome of interest. In this article, evidence that would support the validation of such markers is discussed. Biomarkers used during early clinical development programs of new psychotropic compounds are considered in the contexts of Parkinson's disease, affective disorder, and schizophrenia. The particular case of neuroprotective trials is exemplified by Parkinson's disease, where a biomarker substituting for a clinical measure of progression could be considered as a surrogate treatment outcome.

Next-day residual effects of hypnotics in DSM-IV primary insomnia: a driving simulator study with simultaneous electroencephalogram monitoring.

RATIONALE: Most studies that investigated the next-day residual effects of hypnotic drugs on daytime driving performances were performed on healthy subjects and after a single drug administration. OBJECTIVES: In the present study, we further examine whether the results of these studies could be generalised to insomniac patients and after repeated drug administration. METHOD: Single and repeated (7 day) doses of zolpidem (10 mg), zopiclone (7.5 mg), lormetazepam (1 mg) or placebo were administered at bedtime in a crossover design to 23 patients (9 men and 14 women aged 38.8+/-2.0 years) with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) primary insomnia. Driving tests were performed 9-11 h post-dose. RESULTS: Results showed that treatment effects were evidenced for subjective sleep, for driving abilities, and for electroencephalogram (EEG) recorded before (resting EEG) and during the driving simulation test (driving EEG). Compared to placebo, zopiclone increased the number of collisions and lormetazepam increased deviation from speed limit and deviation from absolute speed, whereas zolpidem did not differentiate from placebo on these analyses. EEG recordings showed that in contrast to zolpidem, lormetazepam and zopiclone induced typical benzodiazepine-like alterations, suggesting that next-day poor driving performance could relate to a prolonged central nervous system effect of these two hypnotics. CONCLUSION: The present results corroborate studies on healthy volunteers showing that residual effects of hypnotics increase with their half-lives. The results further suggest that drugs preserving physiological EEG rhythms before and during the driving simulation test 9-11 h post-dose, such as zolpidem, do not influence next-day driving abilities.

Comparative effects of duloxetine and desipramine on sleep EEG in healthy subjects.

RATIONALE: Antidepressants are known to modify human sleep patterns. OBJECTIVES: Duloxetine is a new antidepressant with a mechanism of action involving reuptake inhibition of both serotonin (5-HT) and norepinephrine (NE). In this study, the effects of two dosing regimens of duloxetine on sleep electroencephalography (EEG) were investigated at steady-state plasma concentrations in young, healthy, male subjects. METHODS: Placebo (n=12), desipramine (50 mg BID; n=12) and two regimens of duloxetine (80 mg QD, n=6; or 60 mg BID, n=6) were compared in a randomized, double-blind, three-period crossover study, each treatment being administered from day 1 to day 7. Sleep polygraphic recordings took place at baseline (day -1) and day 6 of each period. The Leeds sleep evaluation questionnaire (LSEQ) was also administered on the morning of day 7. RESULTS: Both regimens of duloxetine produced a significant increase in the onset latency of REM sleep as well as a significant mean decrease in total REM sleep duration. Desipramine exhibited comparable effects. When compared to placebo, sleep continuity was significantly reduced with desipramine and duloxetine 60 mg BID whereas a significant improvement was observed with duloxetine 80 mg QD. On the LSEQ, duloxetine 80 mg QD produced a significant improvement in the "getting to sleep" subscale compared to placebo, whereas desipramine demonstrated a significant reduction (worsening) in the "quality of sleep" score versus placebo. CONCLUSIONS: The two dose regimens of duloxetine (80 mg QD and 60 mg BID) produced a REM sleep pattern comparable to that of most antidepressant medications. Duloxetine 80 mg QD appeared to exhibit less impact upon sleep quality than duloxetine 60 mg BID in healthy subjects.

Periodic limb movements and sleepiness in obstructive sleep apnea patients.

BACKGROUND AND PURPOSE: The aim of this study was to assess the possibility that periodic limb movements during sleep (PLMS) could play an additive role in the sleepiness associated with obstructive sleep apnea syndrome (OSAS) before treatment, or could account for residual sleepiness in successfully CPAP-treated patients. PATIENTS AND METHODS: In order to test this hypothesis, we compared objective sleepiness, assessed by the Multiple Sleep Latency Test (MSLT) and subjective sleep propensity, assessed by the Epworth Sleepiness Scale (ESS), in a clinical series of 57 patients consecutively diagnosed with OSAS (apnea/hypopnea index, 53.3+/-26.15), before and after 1 year of treatment with CPAP. RESULTS: Twenty-two patients (38.5%) had significant PLMS (at least 5 PLMS/h of sleep; mean 52.9+/-53.9) in absence of apneas (with CPAP). The two groups (with and without PLMS) were similar in gender distribution, BMI, apnea/hypopnea index or CPAP level. Patients with PLMS were older than those without PLMS. Sleepiness measurements following OSAS diagnosis and after 1 year of CPAP treatment were similar in patients PLMS compared to those without significant PLMS. There was no correlation in the PLMS patient group between the PLM index, Epworth Sleepiness Scale score and mean latency in the MSLT. CONCLUSION: In this study we did not find a link between PLMS and increased objective or self-evaluated sleepiness in OSAS patients, before or after treatment with CPAP.

Inverse association between Slow Wave Activity per cycle and the number of ultradian sleep cycles per night in healthy humans.

OBJECTIVE: Comparisons of sleep Slow Wave Activity (SWA) during successive sleep cycles rely on the assumption that SWA in a given cycle is independent of the number of ultradian cycles present in a night. This assumption was evaluated here. METHODS: Twenty-six healthy controls with no medical, sleep or psychiatric disorders were selected among 84 candidates and their sleep was recorded at home across 2 consecutive nights after two habituation nights. RESULTS: In comparison with nights with less cycles, nights with more cycles showed significantly more REMS but not more NREMS. No correlation was found between the number of cycles and the integrated SWA per night (epochs visually scored as NREMS). However, inverse correlations were found between the number of cycles and the SWA per cycle. This was significant on both nights in Cycle 1 and strong trends were found for the two subsequent cycles on Night 2. Comparable results were found after removal of nights containing suspected Skipped First REMS episodes. CONCLUSIONS: The SWA in a cycle was found to be inversely correlated to the number of cycles in the first 3 cycles in at least one of the two analyzed nights. SIGNIFICANCE: Differences in the number of cycles per night are a potential bias in the comparisons of SWA per cycles.

Suicide attempts and family history of suicide in three psychiatric populations.

The influence of a family history of suicide on suicide attempt rate and characteristics in depression, schizophrenia, and opioid dependence was examined. One hundred sixty inpatients with unipolar depression, 160 inpatients with schizophrenia, and 160 opioid-dependent patients were interviewed. Overall, a family history of suicide was associated with a higher risk for suicide attempt, with high-lethality method, with repeated attempts, and with number of attempts, while the interaction between family history and diagnostic group was not significant. Thus, a positive family history of suicide was a risk factor for several suicide attempt characteristics independent of psychiatric diagnosis.

Sleep disturbances, psychiatric disorders, and psychotropic drugs.

Brain neurotransmitter dysfunctions involved in the pathophysiological processes of psychiatric disorders are likely to be reflected by concomitant alterations in sleep continuity and architecture. Since the corrective effects of psychotropic drugs on dysfunctional neurotransmission systems can be evidenced through polysomnographic recordings, one may consider sleep as a kind of "window" on the neurobiology of psychiatric disorders. During the last 10 years, major breakthroughs in our understanding of sleep-wake mechanisms have provided some indications on how psychotropic drugs could influence the sleep-wake cycle. In this review, recent inroads into the understanding of sleep regulatory neural mechanisms are introduced and discussed in terms of the effects of psychotropic drugs. The relationship between the pathophysiological process of a disease, its consequence on sleep, and the corrective effect of a psychotropic drug are exemplified by two psychopathological states: substance withdrawal and major depression. One may conclude that polysomnographic recordings are a unique noninvasive tool to analyze brain functioning, and are particularly well suited to evaluating the objective effects of new psychotropic drugs.

A dimensional impulsive-aggressive phenotype is associated with the A218C polymorphism of the tryptophan hydroxylase gene: a pilot study in well-characterized impulsive inpatients.

Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in the biosynthesis of serotonin, and association and linkage studies of its variants in suicidal and impulsive-aggressive behavior have brought conflicting results. This pilot study was designed to investigate whether TPH A218C genotypes could be associated with impulsive behavioral tendencies (IBTs) in consecutively admitted nonpsychotic nonorganic inpatients. Patients (20 females and 34 males; age, 38.8 +/- 11.8) did not differ from healthy nonimpulsive controls (16 females and 11 males; age, 35.2 +/- 10.2) regarding TPH genotypes, but in the patients, the number of IBT was related to the presence of the 218C allele. It was concluded that impulsive-aggressive behavior may be associated with the TPH genotype in well-characterized impulsive patients and that the present results stress the importance of considering impulsiveness-aggressiveness in studies investigating the relationship between suicidal behavior and TPH genotypes.

Positive association of dopamine D2 receptor polymorphism with bipolar affective disorder in a European Multicenter Association Study of affective disorders.

Convincing evidence for a genetic component in the etiology of affective disorders (AD), including bipolar affective disorder (BPAD) and unipolar affective disorder (UPAD), is supported by traditional and molecular genetic studies. Most arguments lead to the complex inheritance hypothesis, suggesting that the mode of inheritance is probably not Mendelian but most likely oligogenic (or polygenic) and that the contribution of genes could be moderate or weak. The purpose of the present European multicenter study (13 centers) was to test the potential role in BPAD and UPAD of two candidate dopaminergic markers, DRD2 and DRD3, using a case-control association design. The following samples were analyzed for DRD2: 358 BPAD/358 control (C) and 133 UPAD/ 133 C subjects, and for DRD3: 325 BPAD/ 325 C and 136 UPAD/136 C subjects. Patients and controls were individually matched for sex, age ( plus minus five years) and geographical origin. Evidence for significant association between BPAD and DRD2 emerged, with an over-representation of genotype 5-5 (P=0.004) and allele 5 (P=0.002) in BPAD cases compared to controls. No association was found for DRD2 in UPAD, and for DRD3 neither in BPAD or UPAD. Our results suggest that the DRD2 microsatellite may be in linkage disequilibrium with a nearby genetic variant involved in the susceptibility to BPAD. Our large European sample allowed for replicating of some previous reported positive findings obtained in other study populations.

Serotonergic function and suicidal behavior in schizophrenia.

Recent studies suggest that altered serotonergic (5-HT) function, as assessed by lower prolactin (PRL) response to fenfluramine (FEN), a specific 5-HT releaser and uptake inhibitor, is associated with suicidal behavior in either depressed and personality disordered patients. The purpose of this study was to investigate, in schizophrenic patients, the relationship between suicidal behavior and PRL response to D-fenfluramine (D-FEN). A D-FEN test was performed in 18 healthy controls and 33 drug-free DSM-IV schizophrenic patients (12 with a history of suicide attempts, 21 without it). Schizophrenic patients with a history of suicide attempts showed a lower PRL response to D-FEN (Delta PRL) compared to schizophrenic patients without such history (P<0.04) and also compared to healthy controls (P<0.0003). Delta PRL did not differentiate schizophrenic patients without suicide attempts and controls. These findings could not be explained by PRL basal hormonal levels, age, sex, menstrual status, demographic or clinical characteristics. These results suggest that PRL response to D-FEN is a marker of suicidal tendencies also in schizophrenia, supporting the hypothesis that a dysfunction in serotonergic function is associated with suicidal behavior regardless of the psychiatric diagnosis.