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Biomedical subjects

Laura Bellodi

Publications and source records attributed to Laura Bellodi.

35 records · Page 2Linked to original sources
PubMed2004

Approximate entropy of respiratory patterns in panic disorder.

OBJECTIVE: Considerable evidence suggests a connection between panic disorder and respiration, but the nature of the respiratory abnormalities in panic disorder remains unclear. The authors investigated the breath-by-breath complexity of respiration dynamics in panic disorder. METHOD: Respiratory physiology was assessed in 40 patients with panic disorder and 31 healthy comparison subjects by using a breath-by-breath stationary system for testing cardiorespiratory function. Irregularity in the breathing pattern was determined by applying the approximate entropy index, which is an indicator of the irregularity and the "disorder" of the measure. RESULTS: The patients with panic disorder showed significantly higher approximate entropy indexes than the healthy subjects for the measured respiratory parameters. Sighs contributed to the irregularity of breathing patterns but did not account for all the differences in approximate entropy between the patients with panic disorder and the comparison subjects. Anxiety state, severity of illness, and somatic and individual variables such as participation in sports and cigarette smoking did not seem to influence the results. CONCLUSIONS: Patients with panic disorder showed greater entropy in baseline respiratory patterns, indicating higher levels of irregularity and complexity in their respiratory function. Greater respiratory entropy could be a factor in vulnerability to panic attacks.

Adult↗
PubMed2003

Vulnerability to 35% CO2 of panic disorder patients with a history of respiratory disorders.

Patients with panic disorder often report a history of respiratory pathology. Furthermore, panic disorder patients are vulnerable to CO2 challenges. The increased CO2 vulnerability displayed by panic disorder patients may be related to lifetime respiratory pathology. We examined whether panic disorder patients with a history of respiratory disorders are more vulnerable to a 35% CO2 challenge than those without such a history. Ninety-six patients with panic disorder were interviewed about their lifetime respiratory status (asthma, bronchitis and various other respiratory conditions) and underwent the challenge. Immediately before and after the CO2 inhalation, the patients filled out the Visual Analogue Scale for Anxiety (VAS-A) and the Panic Symptom List (PSL). We found no differences between the two panic disorder groups on anxiety (VAS-A), panic symptoms (PSL) or panic attacks after the CO2 challenge. Our results suggest that having a PD is an important factor in CO2 vulnerability independent of a history of respiratory disorders.

Adolescent↗
PubMed2003

Basal-corticofrontal circuits in schizophrenia and obsessive-compulsive disorder: a controlled, double dissociation study.

BACKGROUND: Several lines of research suggest that prefrontal cortex dysfunctions observed in obsessive compulsive disorder (OCD) and schizophrenia (SKZ) are linked to two partially independent neuroanatomic systems: the ventromedial prefrontal cortex and the dorsolateral prefrontal cortex, with different neuroanatomic connections, including the striatum. The primary aim of this study was to test this hypothesis using a double dissociation study of neuropsychological tasks performance of the dorsolateral prefrontal cortex and ventromedial prefrontal cortex. METHODS: We administered the Wisconsin Card Sorting Test, the Gambling Task, and the four-disk version of the Tower of Hanoi to 110 SKZ and 67 OCD patients and 56 control subjects. RESULTS: A clear double dissociation of Wisconsin Card Sorting Test and Gambling Task performances was found, with SKZ patients performing the Wisconsin Card Sorting test significantly worse than OCD patients and control subjects and OCD patients performing the Gambling Task significantly worse than SKZ and control subjects. Both SKZ and OCD patients performed the Tower of Hanoi significantly worse than control subjects. CONCLUSIONS: Results from our double dissociation study confirm the hypothesis of involvement of different frontal lobe subsystems within basal-corticofrontal circuits function in SKZ and OCD.

Adult↗
PubMed2003

Neurosteroid secretion in panic disorder.

Evidence that neurosteroids have anxiolytic effects in animal models of anxiety has suggested that alterations of neurosteroid secretion might be implicated in the pathogenetic mechanisms of anxiety disorders in humans. In 25 female patients with panic disorder (PD) and 11 healthy female controls, we measured plasma concentrations of progesterone (PROG), pregnenolone (PREG), allopregnanolone (3alpha,5alpha-tetrahydroprogesterone=3alpha,5alpha-THPROG), dehydroepiandrosterone (DHEA) and tetrahydrodeoxycorticosterone (3alpha,5alpha-THDOC) during a drug-free month and during the following month of paroxetine therapy. The neurosteroids were measured during the early follicular phase, the mid-luteal phase and the premenstrual phase of both months (days 7, 22 and 27 from the beginning of the cycle). Significantly higher levels in patients than controls were found in PROG during the mid-luteal phase of both months, PREG in the premenstrual phase in the drug-free month, 3alpha,5alpha-THPROG during the follicular phase of the drug-free month and during the premenstrual phase of the therapy month, and 3alpha,5alpha-THDOC during the premenstrual phases of both months. DHEA levels did not differ in patients and controls. These results suggest that neurosteroids in PD are hypersecreted, possibly as an attempt to counteract the anxiogenic underlying hyperactivity of the hypothalamo-pituitary-adrenal axis and to improve a reduced GABA(A) receptor sensitivity.

Adult↗
PubMed2003

Serotonergic modulation of the balance system in panic disorder: an open study.

Experimental evidence suggests that panic disorder is characterized by abnormalities in the balance system function and that these abnormalities might be related to the severity of agoraphobic avoidance. Since the balance system can be modulated by the serotonergic system, we investigated the effect of a 6-week treatment with citalopram on the balance system function in patients with panic disorder. Fifteen patients with panic disorder with/without agoraphobia underwent static posturography on days 0 and 42. Static posturography and clinical assessments were carried out by different investigators who were blind to each other. Static posturography showed high percentages of abnormal scores. Patients with no or low agoraphobic avoidance showed less abnormal posturographic measures than those with moderate to severe agoraphobia. After 6 weeks of treatment with citalopram there was a significant decrease of four out of six posturography measures in eyes-closed and neck extension conditions, whereas no significant effect was found in the eyes-open condition. This is the first report that suggests that the modulation of the serotonergic system can improve the balance system function in patients with panic disorder, particularly when visual information is lacking. In addition, our findings confirm the observation that many patients with panic disorder have abnormalities in their balance system function, supporting the idea that these abnormalities are mainly related to agoraphobic avoidance.

Adult↗
PubMed2003

Anxiety sensitivity and 35% CO2 reactivity in patients with panic disorder.

OBJECTIVE: The present study examines the possible relationships between anxiety sensitivity (AS) and reactivity to the 35% carbon dioxide (CO(2)) challenge in panic disorder (PD). METHODS: One-hundred eight patients with PD underwent the 35% CO(2) challenge and completed the Anxiety Sensitivity Index (ASI). Multiple regression analyses were applied to evaluate the role of AS as a predictor of CO(2)-induced anxiety. RESULTS: Fifty-six patients with PD showed high AS scores, whereas 48 showed medium scores and 4 low scores. ASI scores significantly predicted symptomatological reaction to CO(2) but not subjective induced anxiety. CONCLUSION: These findings suggest that the fear of anxiety-related bodily sensations was related to the symptomatological reactivity to CO(2) but did not seem to play a crucial role in the modulation of the subjective anxiogenic/panicogenic response to hypercapnia in patients with PD.

Administration, Inhalation↗
PubMed2002

Obsessive compulsive disorder among idiopathic focal dystonia patients: an epidemiological and family study.

BACKGROUND: A disturbed function of striato-thalamo-cortical circuitry is hypothesized to underlie idiopathic focal dystonia (IFD) and obsessive compulsive disorder (OCD), two severe and disabling neurologic and psychiatric disorders. Previous studies on small samples showed either higher obsessionality scores or higher frequency of OCD in dystonic patients than in normal control subjects. The aim of this study was to evaluate the frequency and familial loading of OCD in a population of patients with IFD. METHODS: We evaluated OCD diagnosis and family history in 76 patients affected by IFD. RESULTS: Of our subjects 19.7% satisfied DSM-IV criteria for OCD diagnosis and had a family morbidity risk for OCD of 13.8%, significantly higher than that found in the general population. CONCLUSIONS: Our results support the hypothesis of a common pathologic background for OCD and IFD, at least in a subgroup of IFD, indicating basal ganglia dysfunction.

Adult↗
PubMed2002

Anticipation of age at onset of obsessive-compulsive spectrum disorders in patients with obsessive-compulsive disorder.

Anticipation of age at onset has been observed in several neuropsychiatric disorders. Recent studies have associated anticipation with the presence of unstable DNA and have suggested that trinucleotide repeats may be the main cause in some of these diseases. However, several selection biases may mimic the presence of such an effect. In this study we evaluated the presence of this effect in 40 families of probands with obsessive-compulsive disorder (OCD) compared with affected subjects in the parental generation. We controlled for ascertainment biases by taking into account the age at interview of probands. Using a different recruitment strategy, we controlled for anticipation in a sub-sample of offspring of 13 OCD patients, affected with OC spectrum disorders. While the younger generation showed a significantly earlier age at onset than the parental generation, no effect of age at interview was observed. Drawing on the results, we hypothesised that the presence of anticipation in OCD and OC spectrum disorders could be due to a specific genetic effect (unstable DNA), as it has been hypothesised for other disorders showing this effect.

Adult↗
PubMed2002

Exploratory factor analysis of obsessive-compulsive patients and association with 5-HTTLPR polymorphism.

The determination of a genetic basis for obsessive-compulsive disorder (OCD) depends on how phenotypic boundaries are defined. Although a hypothesis for serotonin dysfunction in OCD has been advanced, no genes specifically responsible for serotonin regulation have as yet been definitively related to the etiology of OCD. The phenotypic variability of OCD could be at the basis of the failure of molecular biology investigations to find any genes involved in the liability to the disorder. Obsessive and compulsive contents can aggregate in OCD patients differently; multifactorial description may therefore be able to account for OCD phenotypic variance. Using principal component analysis, we derived five factors from 13 main contents of the Yale-Brown Obsessive-Compulsive Scale (YBOCS), and considered them as quantitative phenotypes to evaluate their possible association with an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR). A trend toward positive association between the fifth factor, including counting and repeating rituals, and 5-HTTLPR was found. However, only considering the subgroup of patients with tic codiagnosis, we found a significantly higher score for the fifth factor for patients with L/L genotype with respect to L/S and S/S genotypes.

Adolescent↗
PubMed2002

Frontal lobe dysfunction in pathological gambling patients.

BACKGROUND: Limited data are available about the validity of the diagnosis of pathological gambling (PG) and about the etiology and the efficacy of different treatment strategies of this disorder; however, similarities in decision-making behavior between PG patients and patients with ventromedial prefrontal cortex lesions suggest a possible implication of these areas in the pathophysiology of this disorder, as in obsessive-compulsive disorder, in which the decision-making impairment is significantly associated with response to serotonin reuptake inhibitor treatment. Nevertheless, several studies have shown that decision-making functioning is also impaired in drug-addicted patients who have shown abnormalities in ventromedial prefrontal cortex during functional neuroimaging studies. METHODS: We assessed the decision-making function mediated by the ventromedial prefrontal cortex in 20 PG patients and 40 healthy control (HC) subjects using the Gambling Task, which simulates real-life decision-making, testing the ability to balance immediate rewards against long-term negative consequence. RESULTS: Significant differences were found in Gambling Task performance between HC subjects and PG patients, who showed a specific decision-making profile across the sequence of the game. The dissimilarity does not appear to depend on the basic cognitive function deficit of the PG group. CONCLUSIONS: These data seem to suggest the existence of a link between PG and other disorders (i.e., obsessive-compulsive disorder and drug addiction) all having diminished ability to evaluate future consequences, which may be explained at least in part by an abnormal functioning of the orbitofrontal cortex.

Adult↗
PubMed2002

Antipanic drug modulation of 35% CO2 hyperreactivity and short-term treatment outcome.

Carbon dioxide (CO2) inhalation induces acute anxiety and panic attacks in patients with Panic Disorder (PD). Anti-panic drugs decrease CO2 reactivity after the first days of treatment; however, the clinical meaning of this finding has not yet been established. This study investigated the effects of treatment with tricyclic antidepressants and selective serotonin re-uptake inhibitors (SSRIs) on CO2 reactivity and compared the relationships between 35% CO2 hyperreactivity modulation and short-term clinical outcome. One hundred twenty-three patients with PD with or without agoraphobia who were hyperreactive to CO2 were randomly assigned to treatment groups with imipramine, clomipramine, paroxetine, sertraline, or fluvoxamine. A double-blind, randomized design was applied. Each patient received the 35% CO2 challenge on days 0, 7, and 30. The severity of clinical symptomatology was measured on days 0 and 30. Decreased hyperreactivity to 35% CO2 in all five treatment groups was already evident after the first week. The decrease in CO2 reactivity at the end of treatment was proportional to the degree of clinical improvement. Multiple regression analyses showed that the decrease in CO2 reactivity after the first week was a significant predictor for good clinical outcome after one month. The results of this study confirm evidence that psychoactive drugs effective in the treatment of PD decrease CO2 hyperreactivity. They also suggest that precocious modulation of CO2 reactivity might fairly reliably predict short-term clinical outcome in patients with "respiratory" PD.

Adult↗
PubMed2002

No association between obsessive-compulsive disorder and the 5-HT(1Dbeta) receptor gene.

OBJECTIVE: Serotonin abnormalities may be involved in the etiopathogenesis of obsessive-compulsive disorder (OCD). The silent G-to-C substitution at nucleotide 861 of the coding region of the 5-HT(1Dbeta) receptor gene may be associated with liability to OCD. The aim of this study was to investigate this association in an Italian OCD study group. METHOD: Genotyping for 5-HT(1Dbeta) was performed for 79 nuclear families of probands with OCD. The transmission/disequilibrium test was used to determine transmission of the alleles from parents to offspring. RESULTS: Of the 79 families, 48 were informative for the analysis, i.e., both parents were genotyped for 5-HT(1Dbeta), and at least one parent was heterozygous. No preferential transmission of either allele of the 5-HT(1Dbeta) gene was observed. CONCLUSIONS: These data do not support a role for the 5-HT(1Dbeta) receptor gene in conferring susceptibility to OCD.

Adult↗
PubMed2000

Novel 5'-regulatory region polymorphisms of the 5-HT2C receptor gene: association study with panic disorder.

Candidate genes for association studies in panic disorder are often selected on the basis of molecular mechanisms of drugs utilized in challenge tests such as m-chlorophenylpiperazine (mCPP), a non-selective 5-HT2C receptor agonist. Two novel, adjacent polymorphisms [(GT)12-18 and (CT)4-5] in the 5'-regulatory region of the X-chromosomal 5-HT2C receptor gene have recently been reported. We determined the allele frequency of long vs. short polymorphism haplotypes in a German and an Italian sample (combined n = 211) of panic disorder patients (DSM-III-R) and compared it with allele frequencies in two ethnically matched control samples (combined n = 226). In the German sample, a comparison of female genotypes containing the short haplotype vs. female genotypes containing only long haplotypes showed a significant difference (p = 0.01, ?2 analysis). In the Italian sample, however, this observation could not be replicated (p = 0.54, ?2 analysis). This argues against a major role for these promoter-associated 5-HT2C receptor gene length polymorphisms in the aetiopathogenesis of panic disorder.

Journal Article↗
PubMedDate not supplied

Investigation of the serotonin transporter regulatory region polymorphism in bulimia nervosa: relationships to harm avoidance, nutritional parameters, and psychiatric comorbidity.

OBJECTIVE: Genes involved in 5HT transmission have been supposed to contribute to the biologic vulnerability for bulimia nervosa (BN). Because a long (L) and a short (S) variant of the promoter region of the 5HT transporter gene have been identified, we tested whether the 5HTT gene-linked polymorphic region (5HTTLPR) could represent a susceptibility factor for BN and/or could be related to nutritional parameters, harm avoidance personality dimension, and psychiatric comorbidity. METHODS: A total of 219 white women (125 bulimics and 94 healthy control subjects) underwent a blood sample collection for 5HTTLPR genotyping and a clinical evaluation assessing comorbidity for axis I and II psychiatric disorders, harm avoidance personality dimension, and body composition (only patients). RESULTS: The distribution of the 5HTTLPR genotypes did not significantly differ between patients and control subjects, although the L allele was significantly more frequent in the former. Bulimic individuals carrying at least one copy of the S allele had significantly lower mean body mass index and body fat mass values and significantly higher mean harm avoidance score than patients with the LL genotype. No significant association was found between the 5HTTLPR genotype and comorbid axis I and II psychiatric disorders. CONCLUSIONS: These findings support the view that polymorphic variants of the 5HTT promoter region do not play a part in predisposing to BN, whereas they seem to predispose bulimic individuals to nutritional impairment and increased harm avoidance.

Adolescent↗