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Biomedical subjects

R B Lydiard

Publications and source records attributed to R B Lydiard.

At least 19 recordsLinked to original sources
PubMed2001

Effectiveness of St John's wort in major depression: a randomized controlled trial.

CONTEXT: Extracts of St John's wort are widely used to treat depression. Although more than 2 dozen clinical trials have been conducted with St John's wort, most have significant flaws in design and do not enable meaningful interpretation. OBJECTIVE: To compare the efficacy and safety of a standardized extract of St John's wort with placebo in outpatients with major depression. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled clinical trial conducted between November 1998 and January 2000 in 11 academic medical centers in the United States. PARTICIPANTS: Two hundred adult outpatients (mean age, 42.4 years; 67.0% female; 85.9% white) diagnosed as having major depression and having a baseline Hamilton Rating Scale for Depression (HAM-D) score of at least 20. INTERVENTION: Participants completed a 1-week, single-blind run-in of placebo, then were randomly assigned to receive either St John's wort extract (n = 98; 900 mg/d for 4 weeks, increased to 1200 mg/d in the absence of an adequate response thereafter) or placebo (n = 102) for 8 weeks. MAIN OUTCOME MEASURES: The primary outcome measure was rate of change on the HAM-D over the treatment period. Secondary measures included the Beck Depression Inventory (BDI), Hamilton Rating Scale for Anxiety (HAM-A), the Global Assessment of Function (GAF) scale, and the Clinical Global Impression-Severity and -Improvement scales (CGI-S and CGI-I). RESULTS: The random coefficient analyses for the HAM-D, HAM-A, CGI-S, and CGI-I all showed significant effects for time but not for treatment or time-by-treatment interaction (for HAM-D scores, P<.001, P =.16, and P =.58, respectively). Analysis of covariance showed nonsignificant effects for BDI and GAF scores. The proportion of participants achieving an a priori definition of response did not differ between groups. The number reaching remission of illness was significantly higher with St John's wort than with placebo (P =.02), but the rates were very low in the full intention-to-treat analysis (14/98 [14.3%] vs 5/102 [4.9%], respectively). St John's wort was safe and well tolerated. Headache was the only adverse event that occurred with greater frequency with St John's wort than placebo (39/95 [41%] vs 25/100 [25%], respectively). CONCLUSION: In this study, St John's wort was not effective for treatment of major depression.

Adult↗
PubMed2001

Noradrenergic function and clinical outcome in antidepressant pharmacotherapy.

Controversy remains regarding the role of noradrenergic systems in determining clinical response to antidepressant pharmacotherapy. Pineal gland production of melatonin can serve as a physiologic index of noradrenergic function. The aim of this study was to examine the effects of antidepressant treatment on 24-hour urinary excretion of the principle metabolite of melatonin, 6-sulfatoxymelatonin in treatment responders and nonresponders. Twenty-four outpatients meeting DSM-III-R criteria for Major Depression received treatment with either fluvoxamine or imipramine for 6 weeks while participating in a placebo-controlled double-blind clinical trial. Twenty-four hour excretion of 6-sulfatoxymelatonin was measured at baseline and at the conclusion of the treatment trial. Changes in urinary excretion of 6-sulfatoxymelatonin distinguished antidepressant responders from nonresponders, with a significant increase observed in the former group and a significant decrease in the latter. The degree of clinical response was correlated with the change in 6-sulfatoxymelatonin excretion. These results suggest that enhanced noradrenergic function may play an important role in determining clinical response to antidepressant pharmacotherapy.

Adrenergic Uptake Inhibitors↗
PubMed2001

Effects of bupropion sustained-release on sexual functioning and nocturnal erections in healthy men.

Many antidepressants are known to cause adverse sexual effects. Bupropion is an antidepressant with fewer reported adverse sexual effects. Studies of sexual side effects are often confounded by psychiatric and medical conditions affecting sexual function. In this study, the effects of bupropion on subjective and objective sexual functioning were measured in healthy men. Thirteen men without psychiatric or medical illness completed a 2-week, placebo-controlled, double-blind, crossover trial of bupropion sustained-release 300 mg/day. Subjects had a 1-week washout period between trials. Sexual function was measured using a validated, self-administered questionnaire and the RigiScan, an instrument measuring nocturnal penile tumescence and rigidity. No differences were found in self-reported sexual function, number of erections, total erection time, or penile rigidity in subjects taking bupropion compared with those taking placebo or baseline. These findings support that bupropion does not have subjective adverse sexual side effects and does not affect nocturnal erections in healthy men.

Adult↗
PubMed2001

Social anxiety disorder: comorbidity and its implications.

Social anxiety disorder is an extremely common and potentially disabling psychiatric disorder. Generalized social anxiety disorder, a subtype of the disorder, is believed to be the most common and most severe form. It is also the form that is most often associated with other psychiatric disorders. Unless the clinician has a high index of suspicion, social anxiety disorder may remain undetected. The clinical and treatment implications of the most common psychiatric comorbidities associated with social anxiety disorder are discussed in this article, with a focus on major depression, panic disorder, posttraumatic stress disorder, and alcohol abuse/dependence. Other psychiatric disorders and some medical conditions commonly associated with social anxiety disorder are briefly mentioned. Finally, a differential diagnosis of social anxiety disorder is described. Individuals who present for treatment of other anxiety disorders, mood disorders, or alcohol/substance abuse disorders should be considered at risk for current but undetected social anxiety disorder.

Adolescent↗
PubMed2000

Elevated plasma thymopoietin associated with therapeutic nonresponsiveness in major depression.

BACKGROUND: Stress predisposes to major depression, and hyperactivity of the stress-activated hypothalamic-pituitary-adrenal (HPA) axis occurs in this disease. Thymopentin, an active fragment of thymopoietin (TP), reduces endocrine and behavioral responses to experimental stress, possibly by lowering plasma TP (pTP) levels. METHODS: Plasma TP and the HPA hormones arginine vasopressin (pAVP), adrenocorticotropic hormone (pACTH), and plasma cortisol (pCORT) were measured in 21 untreated depressed patients and 21 matched control subjects. Clinical responses to antidepressants were evaluated in 17 depressed patients. RESULTS: Plasma TP was elevated in depression (p < .002), with in 8 out of 21 (38%) depressed patients having significant elevations (p < .03). For 17 patients whose antidepressant responses were evaluated, nonresponsiveness occurred in 6 out of 7 (86%) with elevated pTP (>7.5 pg/mL) versus 3 out of 10 (30%) with normal pTP (p < .05). CONCLUSIONS: The significant association of elevated pTP with nonresponsiveness to antidepressant drugs may signify a distinct pathogenesis for the depression of patients with elevated pTP.

Adrenocorticotropic Hormone↗
PubMed2000

Efficacy of venlafaxine extended-release capsules in nondepressed outpatients with generalized anxiety disorder: A 6-month randomized controlled trial.

CONTEXT: Generalized anxiety disorder (GAD) is a chronic disorder that is associated with debilitating psychic and somatic symptoms. Venlafaxine extended-release (XR) capsules have been shown to be effective in short-term treatment of patients with GAD without major depressive disorder (MDD), but long-term data are needed to establish whether this agent confers persistent benefits. OBJECTIVE: To compare the 6-month efficacy and safety of a flexible dosage of venlafaxine XR in outpatients with GAD without associated MDD. DESIGN: Six-month, randomized, double-blind, placebo-controlled, parallel-group trial conducted May 1996 to October 1997. SETTING: Fourteen outpatient clinics and private psychiatric practices in the United States. PARTICIPANTS: A total of 251 outpatients aged 18 years or older who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for GAD, had sufficient symptoms to require treatment, and did not have coexisting MDD. INTERVENTIONS: Participants were randomly assigned to receive either placebo (n=127) or venlafaxine XR (75, 150, or 225 mg/d, as required to control symptoms; n=124) for 28 weeks. MAIN OUTCOME MEASURES: Changes from baseline in the Hamilton Rating Scale for Anxiety (HAM-A) total score, the HAM-A psychic anxiety factor score, and the Clinical Global Impressions (CGI) scale Severity of Illness and Global Improvement scores, compared by intervention group. RESULTS: During weeks 6 through 28, response rates in the venlafaxine XR group were 69% or higher compared with rates of 42% to 46% in the placebo group (P<.001). By an evaluable-patient analysis, venlafaxine XR compared with placebo significantly improved anxiety scores from week 1 or 2 through week 28 on all primary efficacy measures, including the HAM-A total (P<.001), the HAM-A psychic anxiety factor (P<.001), and the CGI scale scores (P<.001). Adjusted mean changes from baseline to week 28 using last-observation-carried-forward methods were for HAM-A, venlafaxine XR -13.4, placebo -8.7 (P<.001); for HAM-A psychic anxiety score, venlafaxine XR -7.4, placebo -4.2 (P<.001); and for CGI-Improvement, venlafaxine XR 2.2, placebo 3.0 (P<.001). The most common treatment-emergent adverse event was nausea, followed by somnolence and dry mouth. CONCLUSIONS: This study is the first placebo-controlled demonstration of the long-term efficacy of any drug class in treating outpatients with DSM-IV-diagnosed GAD. Venlafaxine XR is an effective, rapidly acting, safe, once-daily agent for both the short- and long-term treatment of anxiety and may provide an important alternative to currently available anxiolytics. JAMA. 2000.

Adult↗
PubMed2000

Bupropion-SR in treatment of social phobia.

A 12-week, open label flexible dosing study was conducted to evaluate the efficacy of bupropion-SR in the treatment of generalized social phobia. The primary outcome measures include the Clinical Global Impression of Improvement (CGI-I) and the Brief Social Phobia Rating Scale (BSPS). A total of 18 subjects were enrolled. Five of the ten subjects who completed all 12 weeks were considered as responders. Response to treatment was defined as a CGI-I score of 1 or 2, ("much improved" or "very much improved," respectively) and a > 50% decrease in BSPS score. The final doses for the completers ranged between 200 and 400 mg/day (mean 366 +/- 68 mg/day). The medication was generally well tolerated. Findings from this open-label trial suggest that bupropion-SR may be useful in treating generalized social phobia.

Adult↗
PubMed2000

An overview of generalized anxiety disorder: disease state--appropriate therapy.

OBJECTIVE: This article reviews the prevalence, diagnosis, and treatment of generalized anxiety disorder (GAD). BACKGROUND: Patients with GAD often present to primary care physicians; frequently the disorder manifests with somatic symptoms that have no identifiable physiologic foundation. Accurate diagnosis and treatment often prove elusive, and health care resources are inappropriately consumed in the management of a wide array of complaints, including headache, noncardiac angina, fatigue, insomnia, or abdominal discomfort. Early diagnosis and intervention are critical; GAD is frequently associated with other anxiety and mood disorders, major depressive disorder among them. The differential diagnosis of GAD is complex, including medication side effects and substance-related dependence or withdrawal phenomena, as well as endocrine, neurologic, cardiorespiratory, and autoimmune disorders. CONCLUSIONS: GAD is differentiated from adjustment disorder with anxiety because only GAD can manifest without identifiable emotional stressors; it is differentiated from panic disorder largely on the basis of the chronicity of GAD and the episodic, abrupt nature of panic attacks, with the involvement of at least 4 autonomic, cardiopulmonary, neurologic, or other symptoms. In addition to psychotherapy, education, lifestyle modifications, and social support, several pharmacologic agents may be appropriate therapy for GAD. Given the chronic, nonremitting, relapsing character of GAD, use of benzodiazepines, which confer short-term relief, is usually ill-advised in long-term treatment because these agents can impair cognitive and psychomotor function, interact with various central nervous system depressants (eg, alcohol), and exhibit substantial potential for abuse, tolerance, dependence, and withdrawal effects. Buspirone and certain antidepressants, including the dual noradrenergic-serotonergic reuptake inhibitor venlafaxine, represent first-line therapy for GAD.

Adolescent↗
PubMed2000

Social phobia: diagnosis and epidemiology, neurobiology and pharmacology, comorbidity and treatment.

Social phobia is a common disorder associated with significant psychosocial impairment, representing a substantial public health problem largely determined by the high prevalence, and the lifelong chronicity. Social phobia starts in early childhood or adolescence and is often comorbid with depression, other anxiety disorders, alcohol and substance abuse or eating disorders. This cascade of comorbidity, usually secondary to social phobia, increases the disability associated with the condition. The possibility that social phobia may be a trigger for later developing comorbid disorders directs attention to the need for early effective treatment as a preventive measure. The most recent drug class to be investigated for the psychopharmacological treatment of social phobia is the SSRI group for which there is growing support. The other drug classes that have been evaluated are monoamine oxidase inhibitors (MAOIs), benzodiazepines, and beta-blockers. The SSRIs represent a new and attractive therapeutic choice for patients with generalized social phobia. Recently the first, large scale, placebo-controlled study to assess the efficacy of drug treatment in generalized social phobia has been completed with paroxetine. Paroxetine was more effective in reducing the symptoms than placebo and was well tolerated. Many now regard SSRIs as the drugs of choice in social phobia because of their effectiveness and because they avoid the problems of treatment with benzodiazepines or classical MAOIs.

Adrenergic beta-Antagonists↗
PubMed2000

Placebo-controlled study of gabapentin treatment of panic disorder.

A randomized, double-blind, placebo-controlled, parallel-group study was conducted to evaluate the efficacy and safety of gabapentin in relieving the symptoms of panic disorder. One hundred three patients were randomly assigned to receive double-blind treatment with either gabapentin (dosed flexibly between 600 and 3,600 mg/day) or placebo for 8 weeks. No overall drug/placebo difference was observed in scores on the Panic and Agoraphobia Scale (PAS) (p = 0.606). A post hoc analysis was used to evaluate the more severely ill patients as defined by the primary outcome measure (PAS score > or = 20). In this population, the gabapentin-treated patients showed significant improvement in the PAS change score (p = 0.04). In patients with a PAS score of 20 or greater, women showed a greater response than men regardless of treatment. Adverse events were consistent with the known side effect profile of gabapentin and included somnolence, headache, and dizziness. One patient experienced a serious adverse event during the study. No deaths were reported. The results of this study suggest that gabapentin may have anxiolytic effects in more severely ill patients with panic disorder.

Acetates↗
PubMed2000

Do antidepressants selectively suppress spontaneous (unexpected) panic attacks? A replication.

The purpose of this study was to test the following interrelated hypotheses in a larger sample by attempting to replicate supportive results from a small therapeutic study: (1) the pathogenesis of panic disorder includes at least two identifiable components: a biological component represented by spontaneous (unexpected) panic attacks, and a cognitive component represented by situational attacks and especially by phobias; (2) these components respond differently to treatment; (3) many biological processes respond to an effective intervention in proportion to their deviance from "normal" prior to treatment ("Law of Initial Value"); and (4) the response of spontaneous panic attacks to an effective treatment conforms to that model. Previously, the authors reanalyzed an 8-week therapeutic study of panic disorder that included groups treated with placebo and with imipramine (225 mg daily). The criteria of response were spontaneous panic attacks (biological component), situational panic attacks (both components), and agoraphobia ratings (cognitive component). The analyses compared the regression lines for posttreatment status on pretreatment status in the imipramine and placebo groups. The effect of imipramine on spontaneous panic attacks fitted the hypothesized model: the pre-post slope in the placebo group was approximately 1 (45 degrees), whereas the slope in the imipramine group was approximately 0. There was no significant difference in pre-post slopes between the imipramine and placebo groups for situational panic attacks or agoraphobia ratings. For this report, the authors applied the same approach to another larger data set from a study using a similar design, but a different antidepressant. In this multicenter, double-blind study, patients with panic disorder were randomly assigned to receive 10 weeks of treatment with placebo (N = 78) or fluoxetine 10 mg (N = 84) or 20 mg (N = 81) daily. Spontaneous and situational panic attacks were registered in a daily diary, and agoraphobia was rated at each visit. Using baseline and endpoint data, fluoxetine had a statistically significant, dose-dependent, suppressive effect on spontaneous panic attacks, as measured by the pre-post slopes in the three treatment groups. The placebo group showed some response (slope = 0.69). There were no significant drug effects on situational panic attacks. On ratings of agoraphobia, the slopes in the placebo and the fluoxetine 20 mg groups did not differ, but the slope in the fluoxetine 10 mg group was significantly less than that in the placebo group, suggesting a therapeutic drug effect on agoraphobia only at the lower dose. These results are consistent with the stated hypotheses. They suggest that the therapeutic effects of antidepressants on panic disorder may be due primarily to the specific suppression of spontaneous panic attacks among patients with high baseline pathologic findings. Implications of these results for concepts of pathogenesis, clinical practice, and therapeutic research regarding panic disorder are discussed.

Agoraphobia↗
PubMed2000

Therapeutic advances: paroxetine for the treatment of social anxiety disorder.

Data from early studies of selective serotonin reuptake inhibitors have shown that these agents are effective in the treatment of social anxiety disorder (social phobia). This review highlights the outcomes of three large clinical trials of paroxetine in patients with social anxiety disorder. In two of the studies, patients received a flexible dose of paroxetine (20-50 mg/day) or placebo; the third trial was a fixed-dose study, in which patients received paroxetine 20, 40, or 60 mg/day, or placebo. A total of 861 subjects were randomized to treatment for 12 weeks, in centers across the U.S.A., Canada, Europe, and South Africa. The primary outcome measures were the Clinical Global Impressions (CGI) Global Improvement item and Liebowitz Social Anxiety Scale (LSAS) Total Score. In each of the studies, 45-66% of patients receiving paroxetine were rated as responders (very much or much improved on the CGI scale). Paroxetine treatment improved symptoms of social anxiety, as measured by the LSAS, compared with placebo. Differences between paroxetine and placebo groups were statistically significant and were clinically relevant within each study. In general, paroxetine was well tolerated. Paroxetine is effective for the treatment of social anxiety disorder. Based on the findings from these studies, a starting dose of 20 mg/day is recommended. The range of efficacy appears to be 20-50 mg/day for most patients.

Adolescent↗
PubMed1999

Experience with anxiety and depression treatment studies: implications for designing irritable bowel syndrome clinical trials.

This report highlights various considerations regarding the potential effects of concurrent psychiatric conditions and a history of abuse in patient volunteers for clinical trials in irritable bowel syndrome (IBS). Even though many studies have used psychological rating scales to assess personality and psychological traits of patients with IBS, the prevalence of the different psychiatric diagnoses (i.e., categorical assessment) in patients with IBS has only recently been assessed systematically. Recent studies of treatment-seeking patients have indicated that the majority of individuals (50% to 90%) who seek treatment for IBS have a lifetime history or currently have one or more common psychiatric conditions: major depressive disorder, generalized anxiety disorder, panic disorder, social phobia, somatization disorder, and posttraumatic stress disorder. Traditional clinical wisdom is that the presence of a psychiatric disorder increases the likelihood that an IBS patient will seek treatment. However, recent data suggest that IBS and psychiatric disorders are associated regardless of treatment-seeking status. Patients with psychiatric disorders should be included in clinical IBS studies, because this reflects the actual patient population. Extrapolating from the psychiatric literature, inclusion of patients with IBS with mild to moderate anxiety or depression is warranted.

Anxiety Disorders↗
PubMed1999

Placebo-controlled trial of the CCK-B antagonist, CI-988, in panic disorder.

BACKGROUND: Based on the induction of panic-like symptoms by infusion of cholecystokinin (CCK) peptide in normals and panic disorder patients, it has been proposed that CCK may play a role in the disease mechanisms underlying anxiety disorders. Selective antagonists of CCK-B receptors can block the challenge-induced symptoms in a dose-dependent manner, leading to the hypothesis that these compounds may have anxiolytic effects. METHODS: A randomized, double-blind study was carried out to compare the effects of placebo with CI-988, a selective antagonist of the CCK-B receptors. Following a one-week placebo lead-in, patients with Panic Disorder with or without Agoraphobia received either placebo or CI-988 100 mg TID for six weeks. Panic attacks were recorded by a daily diary method. RESULTS: A total sample of 88 patients was planned but and interim analysis was carried out when about half the patients had been enrolled (n = 41). All patients improved during treatment and no difference in the weekly rate of panic attacks was seen between the treatment groups. The study was terminated at this point due to the remote likelihood of showing a treatment difference. CONCLUSIONS: CI-988 was not superior to placebo in reducing panic attacks. Several explanations are possible, including the poor pharmacokinetic characteristics of CI-988 which may make it unsuitable to test the CCK hypothesis of anxiety.

Adolescent↗
PubMed1999

Feasibility of using fMRI to study mothers responding to infant cries.

While parenting is a universal human behavior, its neuroanatomic basis is currently unknown. Animal data suggest that the cingulate may play an important function in mammalian parenting behavior. For example, in rodents cingulate lesions impair maternal behavior. Here, in an attempt to understand the brain basis of human maternal behavior, we had mothers listen to recorded infant cries and white noise control sounds while they underwent functional MRI (fMRI) of the brain. We hypothesized that mothers would show significantly greater cingulate activity during the cries compared to the control sounds. Of 7 subjects scanned, 4 had fMRI data suitable for analysis. When fMRI data were averaged for these 4 subjects, the anterior cingulate and right medial prefrontal cortex were the only brain regions showing statistically increased activity with the cries compared to white noise control sounds (cluster analysis with one-tailed z-map threshold of P < 0.001 and spatial extent threshold of P < 0.05). These results demonstrate the feasibility of using fMRI to study brain activity in mothers listening to infant cries and that the anterior cingulate may be involved in mothers listening to crying babies. We are currently replicating this study in a larger group of mothers. Future work in this area may help (1) unravel the functional neuroanatomy of the parent-infant bond and (2) examine whether markers of this bond, such as maternal brain response to infant crying, can predict maternal style (i.e., child neglect), offspring temperament, or offspring depression or anxiety.

Adult↗
PubMed1999

Pharmacological treatment of anxiety in the medically ill patient.

Treatment guidelines which are available are intended for treatment of medically healthy patients. There is little information in the literature regarding the treatment of patients who are medically ill. Anxiety and anxiety disorders are frequently encountered in patients with serious medical disorders. These medically ill patients may have substantial changes in pharmacokinetic factors as a result of their current illness or treatment. Also, treatment considerations related to their accompanying medical treatment(s) are sometimes required. These various factors may result in a different initial choice of agents, alterations in the dosage of a given agent, or even preclude the use of some standard agents. In this chapter, we first present a review of the current psychopharmacologic treatment of anxiety disorders. In the second section, we review the potential pharmacokinetic consequences of serious hepatic renal, pulmonary and cardiac disease relevant to the pharmacological treatment of anxiety.

Anti-Anxiety Agents↗
PubMed1999

Evaluation of the efficacy, safety and physiological effects of fluvoxamine in social phobia.

There is no US Food and Drug Administration (FDA) approved treatment for social phobia although data suggest efficacy for several drug classes, including beta-blockers, benzodiazepines, monoamine oxidase inhibitors, and selective serotonin reuptake inhibitors (SSRIs). The SSRIs are particularly attractive due to their favourable tolerance and safety profile. An open label trial of fluvoxamine was conducted to evaluate its efficacy and safety in the treatment of social phobia (DSM-III-R) and to assess physiological changes that may accompany treatment. Fifteen non-depressed patients, aged 22-44 years (mean 31.6 years), entered the study. A 5-min performance task (public speaking simulation) preceded and concluded the active treatment period. Cardiovascular monitoring was performed during this time and blood sampled for plasma cortisol and steady-state plasma fluvoxamine concentration (at week 7). Ten patients (5 men and 5 women) completed an active 6 week treatment period of flexible dosing (50-150 mg/day). Five patients failed to complete the study due to drowsiness (n = 2), nausea (n = 1), or were lost to follow-up (n = 2). Analysis of clinical ratings indicated a statistically significant decrease in all scales from baseline to week 7 at the conclusion of the active treatment period. Clinical benefits were still evident at follow-up 1 week after drug discontinuation. Neither physiological effects nor plasma drug concentration correlated with clinical change. Fluvoxamine appeared to be effective and well tolerated in completers. Randomized clinical trials are needed to further demonstrate the efficacy of fluvoxamine in the treatment of social phobia.

Adult↗