Nocturnal cortisol, thyroid stimulating hormone, and growth hormone secretory profiles in depressed adolescents

Abnormal sleep features in adolescent MDD and its potential in diagnosis and prediction of early efficacy

INTRODUCTION

Previous studies have shown that abnormal sleep architectures are the important indicator for diagnosing MDD and predicting the efficacy of antidepressants. However, few studies have focused specifically on adolescents.

OBJECTIVE

To explore the relationship between abnormal sleep features, including PSG parameters and scale evaluation, and the onset of adolescent MDD, as well as early SSRIs efficacy.

METHODS

102 adolescent MDD patients (age 12 to 19-year-old) and 41 similarly age-marched controls were recruited. Demographic data, the HAMD₂₄ and the PSQI scale assessment scores were collected at baseline, latter two were also collected at follow-up. Part of the participants underwent a minimum 7-d medication-free period, and two consecutive night polysomnography. In the follow-up study, MDD patients were treated with standardized SSRIs. Treatment response was assessed every two weeks.

RESULTS

MDD subjects' parental marital status, REM-sleep latency, N2, N2%, N3, REM-sleep duration, REM % showed significant differences at baseline. REM-sleep latency showed significant prediction of the onset of MDD. The HAMD₂₄ and PSQI scale assessment scores decreased over time in the follow-up study. Specifically, the sleep disorder factor score of HAMD₂₄, the scores of PSQI sleep latency, sleep disorder, sleep efficiency and total score showed significantly differences between responder and non-responder groups. PSQI baseline moderate group showed significant prediction of the early efficacy of SSRIs.

CONCLUSION

Abnormal sleep PSG parameters and self-evaluation could be predictors for the adolescent MDD onset and early SSRIs efficacy.

Cortisol and development of depression in adolescence and young adulthood - a systematic review and meta-analysis

INTRODUCTION

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been implicated in the development of major depressive disorder (MDD) in adulthood. Less work has focused on the role of the HPA axis in depression in adolescence and young adulthood globally. The aim of this study was to conduct a systematic review and meta-analysis of worldwide research investigating the relationship between cortisol, a measure of HPA axis activity, and MDD in adolescence and young adulthood.

METHOD

We searched MEDLINE, PsycINFO, Cochrane Database of Systematic Reviews, Web of Science, Lilacs, African Journals Online, and Global Health for studies which examined the relationship between cortisol and MDD in global youth (10-24 years old).

RESULTS

Twenty-six studies were included in the systematic review and 14 were eligible for the meta-analysis, but only one study included young adults in their sample. Results from the meta-analysis demonstrated that elevated morning, but not evening, cortisol levels was prospectively associated with later MDD development in adolescence and young adulthood. However, morning cortisol levels did not significantly differ between healthy controls and individuals with MDD in cross-sectional studies. Afternoon cortisol and cortisol stress response also did not differ between adolescents with MDD and healthy controls. Qualitative synthesis of the three studies examining nocturnal cortisol showed higher nocturnal cortisol was both longitudinally and cross-sectionally associated with MDD in adolescence.

CONCLUSION

Our findings suggest elevated morning cortisol precedes depression in adolescence. Despite this, we did not find any differences in other cortisol measures in association with MDD in cross-sectional studies. Taken together, these findings suggest that elevated morning and nocturnal cortisol are risk factors for depression in adolescence rather than a biomarker of existing MDD. This supports a role for the hyperactivity of the HPA axis in the development of MDD in adolescence. Most of the studies were from high-income-countries (HICs) and thus further work would need to be conducted in low- and middle-income countries (LMICs) to understand if our findings are generalisable also to these populations.

Lack of Evidence for a Relationship Between the Hypothalamus-Pituitary-Adrenal and the Hypothalamus-Pituitary-Thyroid Axis in Adolescent Depression

In adults with major depressive disorder (MDD), a dysfunction between the hypothalamus-pituitary-adrenal (HPA) and the hypothalamus-pituitary-thyroid (HPT) axis has been shown, but the interaction of both axes has not yet been studied in adolescent major depressive disorder (MDD). Data from 273 adolescents diagnosed with MDD from two single center cross-sectional studies were used for analysis. Serum levels of thyrotropin (TSH), free levothyroxine (fT4), and cortisol were determined as indicators of basal HPT and HPA axis functioning and compared to that of adolescent controls by t-tests. Quantile regression was employed in the sample of adolescents with MDD to investigate the relationship between both axes in the normal as well as the pathological range of cortisol levels, considering confounders of both axes. In adolescent MDD, cortisol levels and TSH levels were significantly elevated in comparison to controls (p = <.001, d = 1.35, large effect size, and p = <.001, d = 0.79, moderate effect size, respectively). There was a positive linear relationship between TSH and cortisol (p = .003, d = 0.25, small effect size) at the median of cortisol levels (50^th percentile). However, no relationship between TSH and cortisol was found in hypercortisolemia (cortisol levels at the 97.5^th percentile). These findings imply that HPT and HPA axis dysfunction is common in adolescents with MDD and that function of both axes is only loosely related. Moreover, the regulation of the HPA and HPT axis are likely subjected to age-related maturational adjustments since findings of this study differ from those reported in adults.

In search of HPA axis dysregulation in child and adolescent depression

Dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis in adults with major depressive disorder is among the most consistent and robust biological findings in psychiatry. Given the importance of the adolescent transition to the development and recurrence of depressive phenomena over the lifespan, it is important to have an integrative perspective on research investigating the various components of HPA axis functioning among depressed young people. The present narrative review synthesizes evidence from the following five categories of studies conducted with children and adolescents: (1) those examining the HPA system’s response to the dexamethasone suppression test (DST); (2) those assessing basal HPA axis functioning; (3) those administering corticotropin-releasing hormone (CRH) challenge; (4) those incorporating psychological probes of the HPA axis; and (5) those examining HPA axis functioning in children of depressed mothers. Evidence is generally consistent with models of developmental psychopathology that hypothesize that atypical HPA axis functioning precedes the emergence of clinical levels of depression and that the HPA axis becomes increasingly dysregulated from child to adult manifestations of depression. Multidisciplinary approaches and longitudinal research designs that extend across development are needed to more clearly and usefully elucidate the role of the HPA axis in depression.

Behavioral adjustment in a community sample of boys: links with basal and stress-induced salivary cortisol concentrations

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been observed in association with internalizing symptoms and is thought to be involved in the pathogenesis of depression and some anxiety disorders. This study examined basal and stress-induced cortisol concentrations in relation to internalizing and externalizing symptoms in a racially mixed community sample of 102 8-11-year-old boys. Afternoon basal cortisol concentrations were positively correlated with measures of internalizing behavior problems, social problems, and emotionality. Greater change in cortisol across a home-visit challenge task was also significantly associated with internalizing behaviors and social problems, as well as attention and thought problems. The implications of these findings and how they may relate to the pathogenesis of emotional and behavioral problems are discussed.

Association of depressive symptoms and anxiety with bone mass and density in ever-smoking and never-smoking adolescent girls

OBJECTIVES

To examine (1) the association of depressive and anxiety symptoms with bone mass and density in adolescent girls and (2) to examine this association in subgroups of those who have ever or never smoked.

DESIGN

Prospective study using baseline reports.

SETTING

Urban teenage health center and the community.

PARTICIPANTS

Two hundred seven girls (aged 11, 13, 15, and 17 years).

OUTCOME MEASURES

Bone mineral density (BMD) and content (BMC) of the hip, spine, and total body determined by dual-energy x-ray absorptiometry. Independent variables included self-report depressive symptoms, anxiety, and smoking history.

RESULTS

Higher depressive symptoms were associated with lower total body BMC and BMD but not hip or spine BMC and BMD. Only in white adolescents was higher state anxiety associated with lower total body BMC and hip BMC and BMD. Ever-smokers were not significantly different than never-smokers in age-adjusted BMC or BMD, but they had higher depressive and anxiety symptoms. Although no significant depression or anxiety by smoking group interactions were found, subgroup analyses suggest that in ever-smokers, higher trait anxiety was related to lower total body BMC.

CONCLUSIONS

This is the first study to report that higher depressive and anxiety symptoms are associated with lower total body BMC during adolescence in girls. Knowing that this association is present at a young age is worrisome, as peak bone mass is attained in adolescence. Findings may aid in identifying girls who are at risk for low bone mass and developing intervention/prevention strategies during adolescence. Importantly, mechanisms that explain these associations and the effect of smoking on bone health need longitudinal examination.

Electroencephalographic sleep and hypothalamic-pituitary-adrenal changes from episode to recovery in depressed adolescents

OBJECTIVE

The study examined electroencephalographic (EEG) sleep and hypothalamic-pituitary-adrenal (HPA) changes associated with depressive episode and during recovery in adolescent depression.

METHODS

Sixteen adolescents with major depressive disorder and 16 volunteers with no personal or family history of psychiatric disorder participated in a three-night EEG sleep protocol along with nocturnal urinary free cortisol (NUFC). Depressed subjects also were restudied during stable remission from the depressive episode.

RESULTS

Compared with controls, depressed adolescents had significantly reduced sleep efficiency, shorter latency to rapid eye movement (REM) sleep, increased phasic REM sleep, and elevated NUFC excretion. Among depressed subjects, EEG sleep values did not change significantly from episode to remission. NUFC excretion reduced significantly during remission from the depressive episode.

CONCLUSIONS

The findings that EEG sleep measures are independent of clinical state, whereas HPA variables are state dependent, suggest that sleep and HPA measures make a differential contribution to our understanding of the pathophysiology and prognosis of mood disorders in adolescent patients.

Medial temporal N-acetyl-aspartate in pediatric major depression

The medial temporal cortex (MTC) has been implicated in the pathogenesis of pediatric major depressive disorder (MDD). Eleven MDD case-control pairs underwent proton magnetic resonance spectroscopic imaging. N-acetyl-aspartate was lower in the left MTC (27%) in MDD patients versus controls. Lower N-acetyl-aspartate concentrations in MDD patients may reflect reduced neuronal viability.

Neurobiology of depression in children and adolescents

This article reviews classical and updated studies of the neurobiology of depressive disorders in children and adolescents. Most studies of childhood and adolescent depression and suicide have followed up the observations and methods used in studies in adults. These studies include neuroendocrine studies, which particularly look at the hypothalamic-pituitary-adrenal axis, the serotonergic system, peripheral blood and cerebrospinal fluid biologic markers, genetics, gene-environment interactions and sleep studies, and neuroimaging and postmortem studies, although in these areas the number of studies is limited.

Peri-sleep-onset cortisol levels in children and adolescents with affective disorders

BACKGROUND

Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol.

METHODS

Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation.

RESULTS

Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression.

CONCLUSIONS

Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation.

The pattern of growth hormone secretion during the menstrual cycle in normal and depressed women

OBJECTIVE

Major depression is associated to altered hypothalamic-pituitary function. Stress is linked to elevated cortisol as well as menstrual cycle disturbance; however, there is no known relationship between depression and menstrual cycle disruption. The aim of this study was to investigate changes of growth hormone (GH) secretion during the menstrual cycle in normal and depressed women.

DESIGN

Case-control study.

PATIENTS AND METHODS

Nineteen women affected with depression and 24 normal controls were included. The two groups had comparable body mass index (BMI), and age (29.4 +/- 9.8 vs. 28.6 +/- 9.7 years). Nine depressed and 10 controls were studied in the follicular phase, while 10 depressed and 14 controls were studied in the luteal phase of the cycle. GH was sampled every 10 min for 24 h, and the data were analysed by the cluster pulse detection method.

RESULTS

There was no difference in 24-h mean GH concentrations between depressed and control subjects (P = 0.93), even after accounting for menstrual cycle phase (P = 0.38). GH pulse frequency was higher during the follicular phase of the cycle (P = 0.032), and nocturnal GH was higher in the follicular phase of the cycle (P = 0.05, and after adjusting for 24-h GH, P = 0.0138) regardless of whether the subjects were depressed or healthy.

CONCLUSIONS

In studies of GH secretion in women with or without depression, it is necessary to control for the phase of menstrual cycle.

Low salivary cortisol levels and externalizing behavior problems in youth

Research linking basal cortisol levels with internalizing and externalizing behavior problems in youths has yielded inconsistent results. We hypothesize that the high moment to moment variation in adrenocortical activity requires an analytical strategy that separates variance in cortisol levels attributable to "stable traitlike" versus "state or situationally specific" sources. Early morning saliva samples were obtained from 724 youths (M age = 13.5 years; range = 6-16 years in Year 1) on 2 successive days 1 year apart. Latent state-trait modeling revealed that 70% of the variance in cortisol levels could be attributed to statelike sources, and 28% to traitlike sources. For boys only, higher levels of externalizing problem behaviors were consistently associated with lower cortisol attributable to traitlike sources across 3 years of behavioral assessment. The inverse association between individual differences in cortisol and externalizing problem behavior has previously only been reported in studies of at-risk or clinical groups. The present findings suggest the relationship is a stable phenomenon that spans both normative and atypical child development. Studies are needed to reveal the biosocial mechanisms involved in the establishment and maintenance of this phenomenon, and to decipher whether individual differences in this hormone-behavior link confers risk or resilience.

Twenty-four-hour cortisol secretion patterns in prepubertal children with anxiety or depressive disorders

BACKGROUND

Previous studies found few abnormalities in hypothalamic-pituitary-adrenal (HPA) axis function in prepubertal children with anxiety or depressive disorders. In this study, we combined data from two independent, consecutive studies to achieve a larger sample size. Our goal was to identify potential alterations in the circadian pattern of cortisol secretion in anxious or depressed children.

METHODS

A total of 124 prepubertal subjects from two independent samples (76 with major depressive disorder, 31 with anxiety disorders, and 17 healthy control subjects) were studied. Blood samples collected for cortisol at hourly intervals over a 24-hour period were examined. Analyses were performed aligning cortisol samples by clock-time. Additional analyses aligning samples by sleep-onset time were performed with a subsample of subjects.

RESULTS

In the combined sample, significant findings emerged that were previously undetected. Anxious children exhibited significantly lower nighttime cortisol levels and an initially sluggish rise in cortisol during the nighttime when compared with depressed and healthy control children. In contrast, depressed children did not show a clear-cut pattern of differences compared with healthy control children.

CONCLUSIONS

Anxious children seem to exhibit an altered pattern of nighttime cortisol secretion, with an initially sluggish or delayed nocturnal rise before reaching similar peak levels of cortisol near the time of awakening. These findings suggest subtle alterations in HPA axis function in prepubertal children with anxiety disorders.

MRI study of the pituitary gland in adolescent depression

Abnormalities in pituitary function have been described in major depressive disorder (MDD) and may reflect neurodevelopmental abnormalities. We hypothesized alterations in the pituitary in early onset MDD. We measured the volume of the pituitary gland in 17 MDD (mean+/-S.D.=16.67+/-1.83 years; 8M, 9F) patients and 17 age and sex matched healthy controls (mean+/-S.D.=16.23+/-1.61 years; 8M, 9F) using 1.45 mm thick T(1)-weighted coronal MRI images. A trained rater blind to diagnosis did all measurements. ANCOVA covarying for age, sex and intracranial volume (ICV) revealed a significant difference between the two groups (F=6.43, df=1, 29, P=0.02; MDD subjects demonstrated a 25% increase in pituitary gland volume). Age was significantly correlated with pituitary volume in the healthy controls (r=0.62, P=0.008) but not the MDD group. No significant relationships between pituitary size and clinical severity were found in the MDD patients. To our knowledge, this is the first study that reports larger pituitary volumes in early onset major depression. These findings provide new evidence of abnormalities of the pituitary in early onset MDD, possibly related to neuroendocrine dysfunction.

Hippocampal volume in early onset depression

BACKGROUND

Abnormalities in limbic structures have been implicated in major depressive disorder (MDD). Although MDD is as common in adolescence as in adulthood, few studies have examined youth near illness onset in order to determine the possible influence of atypical development on the pathophysiology of this disorder.

METHODS

Hippocampal volumes were measured in 17 MDD subjects (age = 16.67 +/- 1.83 years [mean +/- SD]; range = 13 - 18 years) and 17 age- and sex-matched healthy controls (16.23 +/- 1.61 years [mean +/- SD]; 13 - 18 years) using magnetic resonance imaging (MRI).

RESULTS

An analysis of covariance revealed a significant difference between MDD and control subjects (F = 8.66, df = 1, 29, P = 0.006). This was more strongly localized to the left hippocampus (P = 0.001) than the right hippocampus (P = 0.047).

CONCLUSIONS

Our findings provide new evidence of abnormalities in the hippocampus in early onset depression. However, our results should be considered preliminary given the small sample size studied.

Differentiating depressed adolescent 24 h cortisol secretion in light of their adult clinical outcome

A clinical follow-up study was performed of adolescent major depressives and normal control subjects approximately 10 years after the subjects had undergone serial cortisol measurements over a 24-h period. In light of their young adulthood clinical status, our objective was to ascertain whether there were any premorbid cortisol abnormalities associated with depressive course of illness. In all, 77 young adults who had received a diagnosis of adolescent major depressive disorder, or were determined to be normal volunteers free of psychiatric diagnosis at index period and during follow-up, were studied. When subjects were adolescents, blood samples were collected for cortisol at 20-min intervals during the 24-h period coinciding with the third consecutive night of sleep EEG. The subjects, in young adulthood at the time of follow-up, were reinterviewed regarding longitudinal course of illness, and the original adolescent cortisol data were analyzed in the light of information obtained. Of the subjects who had experienced at least one lifetime major depressive episode during the follow-up period, the subgroup who would go on to make suicide attempts during the follow-up period secreted significantly greater levels of cortisol in the 4, 6, and 12 h prior to sleep onset. Conversely, this same subgroup exhibited reduced cortisol levels 2-4 h following sleep onset. Adolescents who are at risk to make suicide attempts appear to display significant elevations of cortisol prior to sleep onset, a time when the hypothalamic-pituitary-adrenal (HPA) axis is normally most quiescent. Dysregulation of the HPA axis, combined with dysfunction of sleep-onset mechanisms previously reported in this same cohort, might serve as premorbid biological substrates that predict suicide attempts during follow-up.

Predictors of response to treatment in children and adolescents with mood disorders

Depression and bipolar disorder are frequently chronic disorders, with onset often beginning in childhood. Mood disorders are becoming more recognized in children and adolescents, and treatment of these disorders has received much attention, particularly in the past 10 years. Recent studies have demonstrated efficacy of antidepressant medications (particularly SSRIs) and specific psychotherapies (primarily CBT). Rates of remission (little or no symptoms) in these studies, however, have remained quite low (35% to 40% in most acute studies). Furthermore, recurrence is common in this population, and affects 40% to 50%. Early onset mood disorders are also associated with increased risk of developing other psychiatric disorders, substance abuse, and suicide, and having poor academic, work, and social functioning. The lifelong implications are serious. Identifying factors that may predict response to treatment, both in general and to specific treatments, may lead to improved outcomes for these patients. Unfortunately, studies have typically been inconsistent. Most studies do not identify demographic variables as predictive of outcome, although older age has been associated with poor prognosis in several studies. Psychosocial factors have yielded some results, particularly with regard to family environments. Generally, intact families with positive interaction styles and less dysfunction have been associated with better outcomes. Psychiatric disorders among parents not only predicts the development of the disorder, but is also associated with poorer prognosis. Finally, several clinical factors have been linked to poorer outcome in children and adolescents with mood disorders. More frequent episodes, increased severity (particularly suicidality and psychosis), and comorbid disorders are likely to lead to fewer recoveries, longer episodes, and increased rate of recurrence. Recent attention has focused on mediators and moderators of outcomes to treatment. In general, the theory is that enumerable factors contribute to the course of an individual's mood disorder, but that by identifying some of the variables that have more impact may allow for more specific or modified treatments to improve outcome. Many of the predictive factors explored in this article are examples of mediators and moderators that affect outcome. Each one alone may not provide definitive answers for predicting response to treatment, but each must be taken into account at the outset of treatment. It is clear that treatments must be individualized for each patient. Furthermore, selecting only one treatment exclusively for patients may hinder progress. The first step is to attempt to identify some of the underlying causes and the consequences of the disorder itself (i.e., decreased social interaction). The next step in successful treatment is to address both the causes and consequences of the disorder, through medication, psychotherapy, skills training, family intervention, or any other methods needed to assist the child to begin functioning better in all domains (social, academic, work, family, and so forth). Such a biopsychosocial approach to treatment of these disorders will likely improve overall outcome.

Long-term effects of childhood abuse on brain and neurobiology

Early stress is associated with long-term alterations in brain circuits and systems that mediate the stress response. Early stressors have lasting effects on the HPA axis and norepinephrine systems. Other brain systems that are involved include benzodiazepine, opiate, dopaminergic, and various neuropeptide systems. These neurochemical systems modulate function in brain regions, including the hippocampus, amygdala, and prefrontal cortex. Long-term alterations in these brain regions are hypothesized to play a role in the maintenance of PTSD, depression, and other psychiatric symptoms after childhood abuse.

The roots of depression in adolescent girls: is menarche the key?

Before adolescence, the rates of depression are similar in girls and boys (or are slightly higher in boys). Yet with the onset of puberty, the gender proportion of depression dramatically shifts to a two girls to one boy ratio. What, then, is the relationship between menarche and the onset of major depression in early adolescence? Recent literature intimates that vulnerability to depression may be rooted in an intricate meld of genetic traits, normal female hormonal maturational processes, and gender socialization. Information regarding gender differences in the presentation of depressive symptoms is provided along with biologic, psychologic, and sociologic factors contributing to depression in adolescent girls. The burden of illness associated with onset of depression after menarche reinforces the importance of prevention or else expeditious recognition and intervention.

Are child-, adolescent-, and adult-onset depression one and the same disorder?

This paper reviews prior research studies examining neurobiological correlates and treatment response of depression in children, adolescents, and adults. Although there are some similarities in research findings observed across the life cycle, both children and adolescents have been found to differ from depressed adults on measures of basal cortisol secretion, corticotropin stimulation post-corticotropin releasing hormone (CRH) infusion, response to several serotonergic probes, immunity indices, and efficacy of tricyclic medications. These differences are proposed to be due to 1) developmental factors, 2) stage of illness factors (e.g., number of episodes, total duration of illness), or 3) heterogeneity in clinical outcome (e.g., recurrent unipolar course vs. new-onset bipolar disorder). Relevant clinical and preclinical studies that provide support for these alternate explanations of the discrepant findings are reviewed, and directions for future research are discussed. To determine whether child-, adolescent-, and adult-onset depression represent the same condition, it is recommended that researchers 1) use the same neuroimaging paradigms in child, adolescent, and adult depressed cohorts; 2) carefully characterize subjects' stage of illness; and 3) conduct longitudinal clinical and repeat neurobiological assessments of patients of different ages at various stages of illness. In addition, careful attention to familial subtypes (e.g., depressive spectrum disorders vs. familial pure depressive disorders) and environmental factors (e.g., trauma history) are suggested for future investigations.

Premorbid polysomnographic signs in depressed adolescents: a reanalysis of EEG sleep after longitudinal follow-up in adulthood

BACKGROUND

This is a report of a clinical follow-up study (10-15 years later as young adults) of adolescent major depressives and normal control subjects. Polysomnographic data were obtained during the original study period when the subjects were adolescent (time 1). With clinical follow-up (time 2) assessments in hand, our objective was to ascertain whether there were any premorbid polysomnographic signs associated with depression during adolescence.

METHODS

Based upon initial (during adolescence) and follow-up clinical assessments (as adults), new subject groupings were generated: depression-free normal subjects and original normal subjects who experienced a depressive episode during the follow-up period (latent depressives). Suicidality and recurrence of depression were also examined. Multivariate analysis of covariance was used to analyze group differences in sleep measures and logistic regression for predicting three outcomes: lifetime depression, lifetime suicidality, and recurrence.

RESULTS

Comparison of the depression-free normal subjects, the latent depressives, and the original major depressives revealed significant differences for sleep latency and sleep period time. Comparing all lifetime depressives (original major depressives and the latent depressives) to depression-free normal subjects revealed significantly more stages 3 and 4 combined (ST34) sleep and greater sleep period times among the depressives. An analysis involving the presence or absence of suicidality revealed no overall significant differences between the groups. Comparison of the lifetime depressives grouped by nonrecurrent and recurrent depressive course to the depression-free normal subjects revealed significant difference for sleep period time. Using logistic regression, we found that a longer sleep latency and sleep period time significantly predicted lifetime depression. Gender, ST34 sleep, and an interaction term for ST34 sleep and REM latency significantly predicted lifetime suicidality.

CONCLUSIONS

There was evidence of premorbid sleep abnormalities during adolescence. A general pattern of sleep disruption around sleep onset and during the first 100 min of the sleep period and overall sleep was evident among the major and lifetime depressives, involving sleep latency (initial insomnia), sleep period time (hypersomnia), REM latency, and slow-wave sleep. This adds to the body of literature that highlights the importance of the first 100 min of the sleep period in depression.

The neuroscience of depression in adolescence

The neuroscience of depression in children and adolescents has only recently become a focus of research. Initially, techniques previously used for adult investigations were employed, such as endocrine studies and sleep studies. Endocrine studies have indicated that, as in adult depression, a dysregulation of the serotonin (5-HT) axis is involved in childhood depression. However, both of these techniques are difficult to perform in children and have yielded some inconsistent results. The more recently developed neuroimaging techniques should enable the greatest advances in our understanding of the pathophysiology of depression. These techniques have already implicated the frontal lobes in the pathogenesis of depression in children and adolescents, and further research is ongoing.

Nocturnal growth hormone secretion studies in adolescents with or without major depression re-examined: integration of adult clinical follow-up data

BACKGROUND

Early sleep is associated with an increased secretion of human growth hormone (GH) through muscarinic inhibition of somatostatin, a GH suppressant. A clinical follow-up was performed approximately 1 decade after depressed and psychiatrically "normal" control adolescents, who were now young adults, had undergone baseline serial GH measurements over a 24-hour period on the third night of sleep polysomnography studies.

METHODS

The study population consisted of 77 young adults who had received a diagnosis of adolescent major depressive disorder and had participated in the adolescent sleep and neuroendocrine studies. Alternatively, the young adult subjects were assessed as normal adolescent control subjects free of any psychiatric diagnosis. Blood samples had been collected for GH every 20 min during the 24-hour period coinciding with the third consecutive night of sleep electroencephalography. Subjects, now in young adulthood, were relocated and blindly reinterviewed using the Schedule for Affective Disorders and Schizophrenia (lifetime version). The original adolescent nocturnal GH data were analyzed in light of the information obtained regarding clinical course into adulthood.

RESULTS

A substantial proportion of the nominally normal control group developed at least one episode of major depression or dysthymia during the follow-up period. "Latent" depressive subjects differed from depression-free control subjects by having exhibited a significantly more rapid increase of adolescent nocturnal GH secretion following sleep onset. Of the subjects who had experienced at least one lifetime major depressive episode during the follow-up, the subgroup who would go on to make suicide attempts secreted significantly greater amounts of GH during the first 4 hours of sleep. Adults with lifetime depression exhibited significantly reduced levels of GH in the 100 min preceding sleep onset during adolescence.

CONCLUSIONS

Assignment of subjects based on longitudinal clinical follow-up into adulthood revealed that the sleep-related GH secretion paradigm has predictive value for future depressive episodes and future suicide attempts. Dysfunction of complex sleep-onset mechanisms may be a premorbid marker of depression and suicidal behavior.

Nontricyclic antidepressants: current trends in children and adolescents

OBJECTIVES

First, to review the extant data on the safety and efficacy of the use of nontricyclic antidepressants in children and adolescents; second, to identify the main limitations of our current knowledge in this area; and third, to point to future research directions.

METHOD

A Medline search and a review of previous scientific meetings were conducted; all available reports on the efficacy and safety of nontricyclic antidepressants in children and adolescents were critically reviewed.

RESULTS

As in adults, also in children nontricyclic antidepressants are potentially useful in treating a variety of psychiatric disorders. The data supporting their efficacy, however, are quite limited. Obsessive-compulsive disorder is the only psychiatric diagnosis for which pediatric use of selective serotonin reuptake inhibitors has been approved. One placebo-controlled study in children and adolescents with major depression supports the efficacy of fluoxetine. Other clinical trials of nontricyclic antidepressants in depressed adolescents are in progress. Available data indicate that the safety of these medications is good, at least in the short term.

CONCLUSIONS

The potential usefulness of nontricyclic antidepressants for children and adolescents suffering from a range of disorders is considerable. While information from adults can suggest potential areas of possible efficacy in pediatric patients suffering from similar psychopathology, further research is essential to provide the necessary information on the efficacy, safety, and pharmacokinetics of these medications in children and adolescents.

Parenteral clomipramine challenge in depressed adolescents: mood and neuroendocrine response

BACKGROUND

Major depressive disorder (MDD) in the adolescent demonstrates a unique clinical profile, and pathogenic serotonergic dysregulation is hypothesized. Parenteral clomipramine (CMI) is known to distinguish adult MDD from control, but neurochallenge data are lacking in adolescent MDD.

METHODS

Thirteen drug-free outpatient adolescents who met DSM-III-R criteria for MDD were compared to adolescent controls by acute neuroendocrine and mood response to 12.5 mg of parenteral CMI.

RESULTS

Repeated measures analysis revealed significant changes from baseline for sadness (p < .01) between groups, with normal controls increasing sadness rating after CMI. Prolactin (PRL) maximum change score from baseline was decreased in MDD relative to controls (p < .05). Gender effects on PRL were evident in controls but not in MDD.

CONCLUSIONS

The findings of PRL blunting in adolescent MDD mirrors previous work in adults. A unique finding is the induction of sadness in normal adolescent controls after CMI infusion.

Psychoneuroendocrinology of children and adolescents

This article reviews psychoneuroendocrinologic approaches to the understanding of internalizing disorders (depression and anxiety disorders) and externalizing disorders. This article discusses three specific psychoneuroendocrine systems: measures of the hypothalamic-pituitary-adrenal (HPA) axis, measure of the serotonergic function, and measures of the growth-hormone (GH) response to pharmacologic challenge. The hypothalamic-pituitary-adrenal (HPA) axis is the main system; understanding this system may reveal information on the permissive and etiologic relationship of stress to psychiatric disorder.

Laboratory and diagnostic testing in child and adolescent psychiatry: a review of the past 10 years

OBJECTIVE

To review in a critical fashion the literature of the past decade covering diagnostic and laboratory testing in the field of child and adolescent psychiatry.

METHOD

A computerized search of articles published during the past decade was made, and selected articles are presented. Because of the paucity of articles specifically relating to minors, selected articles from adult psychiatry are cited.

RESULTS

With a few notable exceptions, few controlled studies on the specificity and sensitivity of any laboratory test for any specific disorder of behavior presenting in children have been conducted in children and adolescents. A high index of suspicion will remain the clinician's best ally in utilizing laboratory measures in the assessment of psychopathology. Nonetheless, studies have appeared that will guide the clinician as to what tests are not clinically useful.

CONCLUSION

Indications and the lack of indications for specific laboratory studies are an integral part of the knowledge base that child psychiatrists must have. Much more empirical data will need to be collected prospectively to inform the field and to move the judicious use of the laboratory from an art to a science.

Depressive disorder in children and adolescents

Depression is a relatively common health issue in children and adolescents. Different pathogenetic factors are implied: genetic, biological, psychological and environmental. The core symptoms of depression are the same for children, adolescents and adults but the prominence of characteristic symptoms changes with age. The clinical picture of depression according to age level is described in different types of mood disorders (major depressive disorder, dysthymia, bipolar disorder) and in mental retardation. Over half of the youths with depression have comorbid conditions: anxiety disorders, other mood disorders, attention deficit/hyperactivity disorder, and conduct disorders. Different factors affect the natural course and risk of suicide. Assessment procedures of depression and comorbid conditions include a psychiatric evaluation of the depressed subject and his family, structured interviews and specific rating scales. A comprehensive treatment strategy, psychoeducational, psychotherapeutic and psychopharmacological, is proposed.

Baseline thyroid hormones in depressed and non-depressed pre- and early-pubertal boys and girls

OBJECTIVE

To examine baseline thyroid hormones in a large group of well-characterized pre- and early-pubertal boys and girls who met criteria for major depressive disorder (MDD) and a comparison group of normal children without psychiatric disorders.

METHODS

45 children with MDD (10.6 years +/- 1.4 year) and 56 healthy controls (10.0 +/- 1.7 year) who participated in a large, psychobiologic protocol are included in this report. As part of the screening for eligibility, baseline samples were drawn for thyroxine (T4), triiodothyronine (T3) uptake, and thyroid stimulating hormone (TSH). Free thyroxine index (FTI) also was computed.

RESULTS

Between-group analyses were carried out controlling for various demographic variables significantly related to thyroid hormones [e.g. age, gender, body mass index (BMI) and their interactions]. For many hormones there were significant effects for age and gender. For T4, MDD boys had lower T4 compared with boys in the normal group. No differences were noted between MDD girls and normal girls. For TSH, MDD boys had lower concentrations compared with normal boys while no differences were noted in girls. For T3 uptake, the MDD group had lower uptake compared with the normal group. For FTI, there were no group differences. Similar to most studies of adults with depression, all our subjects were euthyroid. Unlike the adult studies, we found lower T4 concentrations in the MDD group rather than higher. Group differences in thyroid hormones were noted primarily in boys. The large sample size of this study allowed for the control of multiple variables, which has not been done in past studies. Without such controls, true findings may be masked in other studies of depression. Thus, our findings suggest the possibility of developmental differences in the relation of thyroid hormone and depression.

Utility of thyroid function screening in adolescent psychiatric inpatients

OBJECTIVE

Thyroid function abnormalities have been associated with psychiatric symptoms. This study examines the utility of thyroid screening among adolescent psychiatric inpatients.

METHOD

A retrospective chart review of 196 first-time admissions to an adolescent psychiatric unit was conducted. Charts were screened for demographics, presence/absence of thyroid function testing, history of thyroid disease, medication/illicit substance use, and other factors of influence on thyroid testing. Thyroid test results were reviewed for abnormalities.

RESULTS

Thyroid function testing was conducted in 150 of the 196 admissions. Fifty-two patients had abnormalities, most of which were isolated abnormalities of thyroxine (T4) or triiodothyronine uptake (T3U). Laboratory diagnosis of hyperthyroidism and mild hypothyroidism was met by two and eight patients, respectively; five had profiles that were normal upon subsequent testing 1 week later. None of the patients was symptomatic, and none required thyroid supplementation or antithyroid medications. Gender differences in T4 and T3U were noted, and age was positively correlated with T3U.

CONCLUSIONS

Thyroid function tests may be spuriously abnormal in routine screening of newly admitted psychiatric patients. Routine thyroid screening among adolescent psychiatric inpatients is unwarranted except in patients who display physical signs or symptoms suggestive of thyroid disease.

Childhood and adolescent depression: a review of the past 10 years. Part I

OBJECTIVE

To qualitatively review the literature of the past decade covering the epidemiology, clinical characteristics, natural course, biology, and other correlates of early-onset major depressive disorder (MDD) and dysthymic disorder (DD).

METHOD

A computerized search for articles published during the past 10 years was made and selected studies are presented.

RESULTS

Early-onset MDD and DD are frequent, recurrent, and familial disorders that tend to continue into adulthood, and they are frequently accompanied by other psychiatric disorders. These disorders are usually associated with poor psychosocial and academic outcome and increased risk for substance abuse, bipolar disorder, and suicide. In addition, DD increases the risk for MDD. There is a secular increase in the prevalence of MDD, and it appears that MDD is occurring at an earlier age in successive cohorts. Several genetic, familial, demographic, psychosocial, cognitive, and biological correlates of onset and course of early-onset depression have been identified. Few studies, however, have examined the combined effects of these correlates.

CONCLUSIONS

Considerable advances have been made in our knowledge of early-onset depression. Nevertheless, further research is needed in understanding the pathogenesis of childhood mood disorders. Toward this end, studies aimed at elucidating mechanisms and interrelationships among the different domains of risk factors are needed.

Growth deficits in ADHD children revisited: evidence for disorder-associated growth delays?

OBJECTIVE

To reevaluate the hypothesis that stimulants cause growth deficits in children with attention-deficit hyperactivity disorder (ADHD).

METHOD

Growth deficits in height and weight were examined in 124 children and adolescents with ADHD and 109 controls, using appropriate correction by age and parental height measures and attending to issues of pubertal stage, treatment, and psychiatric comorbidity.

RESULTS

Small but significant differences in height were identified between ADHD children and controls. However, height deficits were evident in early but not late adolescent ADHD children and were unrelated to use of psychotropic medications. There was no evidence of weight deficits in ADHD children relative to controls, and no relationship between measures of malnutrition and short stature was identified.

CONCLUSIONS

ADHD may be associated with temporary deficits in growth in height through mid-adolescence that may normalize by late adolescence. This effect appears to be mediated by ADHD and not its treatment.

The relationship between longitudinal clinical course and sleep and cortisol changes in adolescent depression

This study examined the relationship between longitudinal clinical course and sleep and cortisol findings in adolescent unipolar major depressive disorder (MDD). Subjects were 28 adolescents (15.4 +/- 1.3 years) systematically diagnosed with unipolar MDD and 35 group-matched normal controls who participated in EEG sleep and neuroendocrine studies. Follow-up clinical assessments were conducted 7.0 +/- 0.5 years later in 94% of the original cohort. Although initial group comparisons failed to show significant differences in biologic measures, analyses incorporating clinical follow-up reveal that changes in sleep and cortisol measures are associated with differential longitudinal course. Normal controls who would develop depression after the biologic studies had shown significantly higher density of rapid eye movements (REM) and a trend for reduced REM latency compared to controls with no psychiatric disorder at follow-up. Depressed subjects with a recurrent unipolar course showed a trend towards elevated plasma cortisol near sleep onset compared to MDD subjects with no further episodes during the follow-up interval.

Nocturnal ACTH, cortisol, growth hormone, and prolactin secretion in prepubertal depression

OBJECTIVE

To examine nocturnal secretion of adrenocorticotropin, cortisol, growth hormone, and prolactin in 38 medically healthy children with prepubertal major depression compared with 28 medically and psychiatrically healthy control children.

METHOD

Prior to sampling, subjects underwent an "adaptation night" with the intravenous catheter in place and electroencephalographic (EEG) electrodes for standard all-night polysomnogram. On the following night, plasma samples were obtained every 20 minutes through an indwelling catheter. Hormonal concentrations were measured by specific radioimmunoassay and aligned by EEG-confirmed sleep onset. Areas under the curve were calculated for total secretion and compared using analysis of variance.

RESULTS

Prepubertal depressed children had lower cortisol secretion during the first 4 hours after sleep onset compared with controls. Adrenocorticotropin, prolactin, and growth hormone secretion did not differ between groups. Examination of clinical characteristics in depressed children revealed lower nocturnal adrenocorticotropin concentrations in depressed inpatients versus depressed outpatients and in depressed sexually abused versus depressed nonabused children. A significant sex by diagnosis effect revealed lower growth hormone secretion in depressed females compared with depressed males.

CONCLUSIONS

In contrast to neuroendocrine challenge studies in these same subjects, nocturnal neuroendocrine measures did not reveal any of the expected group differences. These results emphasize the contrasts between unstimulated and challenge studies of neuroendocrine secretion and of the importance of considering clinical characteristics and maturation influences in biological studies of prepubertal depression.

Adrenal secretion during major depression in 8- to 16-year-olds, I. Altered diurnal rhythms in salivary cortisol and dehydroepiandrosterone (DHEA) at presentation

The association between basal cortisol, dehydroepiandrosterone (DHEA), its sulphate (DHEAS) and major depression was investigated in 8- to 16-year-olds. Eighty-two subjects with major depression, 25 non-depressed psychiatric cases and 40 community controls were systematically assessed for current mental state and hormone levels at 08.00, 12.00 and 20.00 h, assayed from salivary samples collected over a 48 h period. The average mean of the two time points was compared between the three groups. Evening cortisol hypersecretion and morning DHEA hyposecretion were significantly, and independently, associated with major depression. High evening cortisol (> 0.594 ng/mL) and low morning DHEA (< 0.200 ng/mL) identified subgroups of depressives with different types of adrenal hormone dysregulation. The association between high evening cortisol or low morning DHEA and MDD was not affected by either age or gender.

Thyroid hormone concentrations in depressed and nondepressed adolescents: group differences and behavioral relations

OBJECTIVE

To examine thyroid hormone concentrations and the influence of these hormones on mood and problem behaviors in adolescents with depression.

METHOD

The sample included 21 depressed adolescents and 20 matched control adolescents. Blood was drawn to measure thyroid-stimulating hormone (TSH), free thyroxine (FT4), thyroxine (T4), and triiodothyronine (T3). Major depression (MD), attention deficit (AD), and obsessive-compulsive (OC) symptom scores were abstracted from the Diagnostic Interview Schedule for Children. Total behavior problem scores from the Youth Self-Report also were obtained.

RESULTS

Paired analysis revealed there were no significant group or gender differences or group by gender interactions for TSH, T4, or T3. For FT4, however, there were significant group differences (p = .008) showing lower concentrations in depressed adolescents than control subjects, suggesting that the former might be functionally hypothyroid. Although there were no significant correlations of TSH with any of the psychological measures obtained, in the depressed group correlations were negative (although not always significant) with FT4 and total behavior problems (r = -.40, p = .09), as well as with symptom scores of MD (r = -.25, p = .288), OC (r = -.56, p = .011), and AD behaviors (r = -.57, p = .008). Higher numbers of symptom scores of OC and AD were related to lower concentrations of FT4.

CONCLUSIONS

FT4 concentrations were lower in depressed adolescents. These findings suggest a relationship between negative behaviors and dysfunction of the hypothalamic-pituitary-thyroid axis in adolescents with depression.

Corticotropin-releasing hormone challenge in prepubertal major depression

This study investigates cortisol and ACTH (corticotropin) responses to an infusion of human CRH (corticotropin-releasing hormone) in prepubertal children with major depressive disorder (MDD). Following a period of 24 hours of adaptation to the laboratory environment with an intravenous catheter in place, 34 children with MDD and 22 healthy controls received 1 microgram/kg of human CRH at 5:00 PM. Blood samples for cortisol and ACTH were measured at baseline and post-CRH. Overall, there were no significant differences between the MDD and the normal controls in baseline or post CRH stimulation values of either cortisol or ACTH. Melancholic (n = 4) patients had significantly higher baseline cortisol levels than nonmelancholic (n = 24) patients. Compared with the outpatients and the nonmelancholics, the inpatients (n = 10) and the melancholics showed significantly lower total ACTH secretion (effect size: 0.9 and 1.4, respectively) after CRH infusion. These results are consistent with a broad literature suggesting that the HPA axis abnormalities occur less frequently in early-onset depression than reported in adult studies. The pattern of results in the subgroups of inpatients and in melancholic children, however, raise questions about possible continuities with adult studies.

Sleep EEG features of adolescents with major depression

A substantial body of research in adults has established that certain sleep polysomnographic abnormalities are commonly found in depressed patients, including sleep continuity disturbances, reduced slow-wave sleep, shortened rapid eye movement (REM) latency and increased REM density. To date the findings in depressed adolescents are equivocal. Three consecutive nights of polysomnographic recordings were obtained in 31 hospitalized depressed adolescents and 17 age-matched normal controls. The depressed adolescents had a shorter REM latency, shorter sleep latency, more REM sleep, and less stage 3 nonREM (NREM) sleep. There was a trend for melancholic and suicidal patients to have a shorter REM latency.

Salivary testosterone and cortisol in disruptive children: relationship to aggressive, hyperactive, and internalizing behaviors

OBJECTIVE

To test predictions that basal salivary testosterone and cortisol are related to antisocial and internalizing behaviors, respectively, and that cortisol moderates the testosterone-aggression relationship.

METHOD

Saliva samples were assayed to determine testosterone and cortisol levels in 40 clinic-referred disruptive children (aged 7 through 14 years) who were rated on aggression, inattention/overactivity, and internalizing behavior by parents, teachers, and clinic staff members.

RESULTS

Results indicated significant positive relationships between testosterone and staff-rated aggression and between cortisol and parent-rated internalizing behavior. A significant negative relationship was found between cortisol and staff-rated inattention/overactivity. No interactions between testosterone and cortisol were found. These results were maintained regardless of age, racial background, height, weight, diagnosis, or medication status.

CONCLUSIONS

Results suggest moderate relationships between testosterone and observed aggression, and between cortisol and emotional behaviors, in a group of disruptive children. Cortisol did not moderate the testosterone-aggression relationship in this population.

Growth hormone response to growth hormone releasing hormone and to clonidine stimulation in peripubertal patients with major depressive disorder

The responses of growth hormone (GH) to administration of growth hormone-releasing hormone (GHRH-1 micrograms/kg b.w.) and of clonidine (clon-2.5 micrograms/kg b.w.) and basal levels of somatomedin C (SmC) were measured in nine peripubertal patients with Major Depressive Disorder (MDD) and in 9 age- and gender-matched controls. Basal GH and SmC levels, and GH response to GHRH did not differ in patients and controls, whereas responses to clonidine were significantly higher in some and lower in other patients than in controls.

Response to desipramine treatment in adolescent depression: a fixed-dose, placebo-controlled trial

OBJECTIVE

To determine the efficacy and tolerability of the tricyclic antidepressant desipramine (DMI) in the treatment of DSM-III-R-diagnosed major depressive disorder in adolescents.

METHOD

Sixty adolescents (42 female, 18 male; aged 15 to 19 years) diagnosed with major depressive disorder using clinical interview and Schedule for Affective Disorders and Schizophrenia for School-Age Children were randomized to receive either DMI (200 mg daily in divided doses) or placebo for six consecutive weeks following a 1-week placebo period. Treatment outcome was determined using the Hamilton Depression Rating Scale and the Beck Depression Inventory. Tolerability was determined using a symptom side effects scale. In addition, a variety of laboratory and cardiovascular monitoring was performed.

RESULTS

No significant differences in treatment outcome between DMI- and placebo-treated groups were determined. Neither DMI, nor its metabolite 2-hydroxy-DMI, nor their ratio, was positively correlated to treatment outcome. The DMI group endorsed more side effects but there were no significant between-group differences in any laboratory, electrocardiographic, or other cardiovascular parameters apart from heart rate, which was increased in the DMI-treated group (p = .03).

CONCLUSIONS

Given the findings of this study and our review of previously published reports of tricyclic antidepressant treatment in this population, the routine use of short-term (6 weeks) DMI in the treatment of adolescent depression is not supported by the data on hand. Further investigations into what constitutes optimal psychopharmacological treatment of adolescent depression are warranted.

Basal thyroid indices in adolescent depression and bipolar disorder

OBJECTIVE

Abnormalities of the thyroid axis are documented in adult mood disorders. The most consistent findings have been observed in major depressive disorder with elevations of thyroxine (T4) or free-T4 (fT4) within the euthyroid range that decrease with treatment. The literature on adolescents is limited, and it is unknown whether similar findings might be present in this population.

METHOD

First admissions to a university hospital adolescent psychiatry unit were reviewed. Fourteen depressed and 13 manic patients satisfied inclusion and exclusion criteria. None had a history of thyroid illness or medical illness or were taking medications known to affect thyroid function. Basal serum thyrotropin, T4, fT4, triiodothyronine (T3), reverse-T3, free thyroxine index (FTI), and T3 resin uptake levels were compared with those of a group of adolescent normal controls.

RESULTS

T4 (but not fT4) was elevated in depressed and manic patients compared with controls (p < .05). In manic patients, T3 was decreased and reverse-T3 was increased (p < .05). There were no significant differences in relation to age, sex, or suicidality.

CONCLUSIONS

We observed significant differences in basal thyroid hormone levels in depressed and manic adolescents. Our results suggest the presence of abnormalities of thyroid function in adolescent mood disorders similar to those described in mood-disordered adults.

Sleep-related growth hormone secretion is persistently suppressed in women with recurrent depression: a preliminary longitudinal analysis

Growth hormone secretion was monitored during sleep in a group of 43 women with recurrent major depression who were participating in a 3-year maintenance therapy program. Patients were studied before acute treatment, after complete remission, and at 3-month intervals during maintenance treatment and the data generated were compared to those obtained in a control group of 14 age-matched healthy women studied once under identical conditions. When compared to the control group, the depressed patients secreted significantly less growth hormone before treatment. This reduction in growth hormone secretion, which was confined to the first half of the sleep period, persisted across the length of the maintenance study regardless of whether the subjects completed three years of therapy or experienced a recurrence.