Role of pill-taking, expectation and therapeutic alliance in the placebo response in clinical trials for major depression.

BACKGROUND: Pill-taking, expectations and therapeutic alliance may account for much of the benefit of medication and placebo treatment for major depressive disorder (MDD). Aims To examine the effects of medication, placebo and supportive care on treatment outcome, and the relationships of expectations and therapeutic alliance to improvement. METHOD: A total of 88 participants were randomised to 8 weeks of treatment with supportive care alone or combined with double-blind treatment with placebo or antidepressant medication. Expectations of medication effectiveness, general treatment effectiveness and therapeutic alliance were measured (trial registration at ClinicalTrials.gov: NCT00200902). RESULTS: Medication or placebo plus supportive care were not significantly different but had significantly better outcome than supportive care alone. Therapeutic alliance predicted response to medication and placebo; expectations of medication effectiveness at enrolment predicted only placebo response. CONCLUSIONS: Pill treatment yielded better outcome than supportive care alone. Medication expectations uniquely predicted placebo treatment outcome and were formed by time of enrolment, suggesting that they were shaped by prior experiences outside the clinical trial.

High rates of comorbid depressive and anxiety disorders among women with premutation of the FMR1 gene.

Phenotypic variations are emerging from investigations of carriers of the fragile X mental retardation 1 (FMR1) premutation gene (55 to 200 CGG repeats). Initial studies suggest elevated psychiatric and reproductive system dysfunction, but have largely used self-reports for assessment of psychiatric history. The present study used diagnostic psychiatric interviews and assessed reproductive and menstrual history in women with FMR1 premutation. History of psychiatric diagnoses and data on reproductive functioning were collected in 46 women with FMR1 premutation who were mothers of at least one child with the fragile X full mutation. Results showed a significantly earlier age of menopause (mean age = 45.6 years) relative to the national average age of menopause (mean age = 51 years) and a high rate (76%) of lifetime depressive or anxiety history, with 43% of the overall sample reporting a comorbid history of both diagnoses. Compared to those free of psychiatric history, significantly longer premutation length was observed among women with psychiatric history after adjusting for age, with comorbid women having the highest number of CGG repeats (mean = 95.8) compared to women free of psychiatric history (mean = 79.9). Psychiatric history did not appear significantly related to reproductive system dysfunction, though results may have been obscured by the high rates of psychiatric dysfunction in the sample. These data add to the growing evidence base that women with the FMR1 premutation have an increased risk of psychiatric illness and risk for early menopause. Future investigations may benefit from inclusion of biochemical reproductive markers and longitudinal assessment of psychiatric and reproductive functioning.

Escitalopram but not placebo modulates brain rhythmic oscillatory activity in the first week of treatment of Major Depressive Disorder.

Serotonin modulates brain oscillatory activity, and serotonergic projections to the thalamus and cortex modulate the frequency of prefrontal rhythmic oscillations. Changes in serotonergic tone have been reported to shift oscillations between the combined delta-theta (2.5-8 Hz) and the alpha (8-12 Hz) frequency ranges. Such frequency shifts may constitute a useful biomarker for the effects of selective serotonin reuptake inhibitor (SSRI) medications in Major Depressive Disorder (MDD). We utilized quantitative electroencephalography (qEEG) to measure shifts in prefrontal rhythmic oscillations early in treatment with either the SSRI escitalopram or placebo, and examined the relationship between these changes and remission of depressive symptoms. Prefrontal delta-theta and alpha power were calculated for 194 subjects with moderate MDD prior to and one week after start of treatment. Changes at one week in delta-theta and alpha power, as well as the delta-theta/alpha ratio, were examined in three cohorts: initial (N = 70) and replication (N = 76) cohorts treated with escitalopram, and a cohort treated with placebo (N = 48). Mean delta-theta power significantly increased and alpha power decreased after one week of escitalopram treatment, but did not significantly change with placebo treatment. The delta-theta/alpha ratio change was a specific predictor of the likelihood of remission after seven weeks of medication treatment: a large increase in this ratio was associated with non-remission in escitalopram-treated subjects, but not placebo-treated subjects. Escitalopram and placebo treatment have differential effects on delta-theta and alpha frequency oscillations. Early increase in delta-theta/alpha may constitute a replicable biomarker for non-remission during SSRI treatment of MDD.

Antidepressant treatment history and drug-placebo separation in a placebo-controlled trial in major depressive disorder.

RATIONALE: A history of antidepressant treatment may predispose subjects toward placebo nonresponse in randomized controlled trials (RCTs) in major depressive disorder (MDD). OBJECTIVE: The objective of this study is to examine self-reported prior antidepressant treatment and response in relationship to clinical outcome in an 8-week randomized trial of reuptake inhibitor antidepressant medication (MED) versus placebo (PBO) administered along with limited supportive care. METHODS: Chi-square and MMRM analyses examined MED vs. PBO outcomes in antidepressant-naïve vs. antidepressant-experienced subjects. Linear regression models examined treatment history along with covariates as predictors of clinical improvement. RESULTS: Among completers (n = 56), there was no significant difference in response rate between MED (53.3 %) and PBO (42.3 %) (χ (2) = 0.33, p = 0.28, 1-tailed). The antidepressant-experienced subgroup (n = 37), however, showed a significantly greater response rate to MED (52.4 %) than PBO (25.0 %) (χ (2) = 2.82, p = 0.047, 1-tailed). The full intent-to-treat (ITT) sample (n = 69) did not show a significant difference between MED and PBO group improvement over time, but in the treatment-experienced subgroup (n = 46), MED showed significantly greater improvement than PBO (coefficient = .39, SE = .23, p = .045, 1-tailed). A history of prior antidepressant treatment predicted poorer overall response independent of pretreatment symptom severity, number or length of previous episodes, subject expectations, or family history of MDD. CONCLUSIONS: Treatment history appears to constitute a factor that is distinct from other commonly studied illness characteristics or expectancy measures, and that impacts overall response as well as drug-placebo separation in RCTs.

Externalizing disorders in adolescence mediate the effects of maternal depression on substance use disorders.

Maternal depression has been linked to increased risk of substance use disorders (SUDs) in offspring. Cross-sectional studies have identified relationships among maternal depression, externalizing disorders and SUDs, but no longitudinal examination of causality has been undertaken. In order to address this gap in the literature, depression and externalizing disorders at or prior to age 15 were tested as mediators of the relationship between maternal depression and SUDs diagnosed between ages 16 and 20 in a sample of 702 Australian youth (363 women) using path models. Mothers' and fathers' substance diagnoses and earlier onset of substance abuse in youth were controlled for in all analyses. Consistent with previous work, maternal depression predicted SUDs between ages 16 and 20. An indirect effect of maternal depression through youth externalizing disorders diagnosed by age 16 was detected for alcohol and cannabis use disorders, but not drug disorders. Early adolescent depression was not a mediator of the relationship between maternal depression and any of the substance outcomes measured. To our knowledge, this study is the first to examine depression and externalizing disorders in early adolescence as mediators of the effect of maternal depression on psychopathology in later adolescence. Further work is needed to understand how family environment and genetic factors may explain the mediation by externalizing disorders.

Endogenous opioid system influences depressive reactions to socially painful targeted rejection life events.

Although exposure to a recent major life event is one of the strongest known risk factors for depression, many people who experience such stress do not become depressed. Moreover, the biological mechanisms underlying differential emotional reactions to social adversity remain largely unknown. To investigate this issue, we examined whether the endogenous opioid system, which is known to influence sensitivity to physical pain, is also implicated in differential risk for depression following socially painful targeted rejection versus non-targeted rejection life events. Adolescents (n=420) enrolled in a large longitudinal birth cohort study had their recent stress exposure and current mental health status assessed using self-report and interview-based methods. Participants were also genotyped for the A118G polymorphism in the µ-opioid receptor gene (OPRM1, rs1799971), which has been found to influence neural and psychological responses to rejection, likely by affecting opioid receptor expression and signaling efficiency. As hypothesized, G allele carriers, who are known to exhibit less opioid receptor expression and signaling efficiency, were more severely depressed and twice as likely to meet criteria for major depressive disorder following a recent targeted rejection major life event (e.g., being broken up with, getting fired) relative to A/A homozygotes who experienced such stress. However, A118G genotype did not moderate the effects of other similarly severe major life events on depression. These data thus elucidate a biological pathway that may specifically influence sensitivity to social pain and rejection, which in turn has implications for understanding differential risk for depression and several other social stress-related disorders.

Heart rate variability and treatment outcome in major depression: a pilot study.

Variations in heart rate variability (HRV) have been associated with major depressive disorder (MDD), but the relationship of baseline HRV to treatment outcome in MDD is unclear. We conducted a pilot study to examine associations between resting baseline HRV and MDD treatment outcome. We retrospectively tested several parameters of HRV in an MDD treatment study with escitalopram (ESC, N=26) to generate a model of how baseline HRV related to treatment outcome, and cross-validated the model in a separate trial of MDD treatment with Iyengar yoga (IY, N=16). Lower relative power of very low frequency (rVLF) HRV at baseline predicted improvement in depressive symptoms when adjusted for age and gender (R2>.43 and p<0.05 for both trials). Although vagal parasympathetic measures were correlated with antidepressant treatment outcome, their predictive power was not significant after adjusting for age and gender. In conclusion, baseline resting rVLF was associated with depression treatment outcome in two independent MDD treatment studies. These results should be interpreted with caution due to limited sample size, but a strength of this study is its validation of the rVLF predictor in an independent sample. rVLF merits prospective confirmation as a candidate biomarker.

A prospective study of stress and alcohol craving in heavy drinkers.

Recent work has examined the relationship between stress and relapse to alcohol use in clinical populations. Few prospective studies, however, have examined stress as a precipitant of alcohol problems. The present study is a longitudinal examination of the role of stress reactivity and alcohol craving in the etiology of alcohol problems in a sample of 41 (mean age=20.8), heavy-drinking, young adults. Participants completed a guided imagery exposure to stressful life events, followed by exposure to a neutral imagery control. Following the exposure, participants completed an alcohol cue exposure paradigm. Measures of negative mood (Profile of Mood States (POMS) depression/dejection scale), tension (POMS tension/anxiety scale) and alcohol craving (measured by the Alcohol Urge Questionnaire (AUQ)) were used as indicators of reactivity to stress and to alcohol cues. Polymorphisms of the corticotropin-releasing hormone binding protein (CRH-BP) gene and of the µ-opioid receptor (OPRM1) gene were examined as moderators of this relationship. Results revealed that stress-induced negative mood predicted negative consequences of drinking (scores on the Drinker's Inventory of Consequences (DrInC-2R)), whereas stress and cue-induced alcohol craving did not predict alcohol use or problems. Additionally, the CRH-BP genotype was found to moderate the relationship between stress-induced negative affect and the negative consequences of drinking. The current study supports and extends laboratory research describing phenotypes of stress-induced alcohol craving.

The Serotonin Transporter Polymorphism (5-HTTLPR) and Alcohol Problems in Heavy Drinkers: Moderation by Depressive Symptoms.

Heavy alcohol use in young adults has been prospectively associated with a host of psychosocial and alcohol-related problems. Recent studies have supported the interaction between serotonin transporter polymorphism and adverse environmental factors, as a predictor of alcohol use and the development of alcohol dependence. The current study examined the role of depressive symptoms in combination with the serotonin transporter polymorphism as a predictor of alcohol use and alcohol-related problems. Results revealed a significant genotype by depressive symptom interaction, such that heavier alcohol use was associated with depressive symptoms in L allele homozygotes but not among S allele carriers. These results remained significant after controlling for ethnicity and gender effects. These findings extend the emerging literature supporting 5-HTTLPR genotype as a risk factor for alcohol-related problems in the context of co-occurring symptoms of depression.

Application of human laboratory models to pharmacotherapy development for alcohol dependence.

Human laboratory studies have a rich history in the alcoholism field and several important determinants of alcohol use disorders have been successfully modeled under controlled laboratory conditions. Laboratory paradigms have been employed to identify biobehavioral risk markers for alcohol misuse and more recently, have been integrated with behavioral genetic, neuroimaging, and pharmacological approaches to further elucidate the neuropathophysiology of addiction and to screen for efficacious treatments. This review will address the rationale and application of human laboratory models to advance pharmacotherapy development for alcohol dependence. It is argued that when properly implemented, laboratory models may help scientists and clinicians understand mechanisms of pharmacotherapy response, which in turn may inform efforts to optimize the currently available and newly developed treatments for alcoholism. Limitations and future directions are discussed.