Neuroendocrine aspects of primary endogenous depression--IV. Pituitary-thyroid axis activity in patients and matched control subjects

Subclinical thyroid dysfunction and major depressive disorder

PURPOSE

This review attempts to investigate the link between subclinical thyroid dysfunction (SCH) and major depressive disorder (MDD). It has been speculated that SCH may be related to MDD through an autoimmune mechanism.

METHODS

A comprehensive literature search was conducted in the PubMed database for relevant research and review articles.

RESULTS

There appears to be an association between an autoimmune mechanism, possibly involving the thyroid gland, and depressive disorders, but the available evidence is so far inconclusive.

CONCLUSION

Lifetime prevalence of depression is significantly higher in patients with SCH, a finding reflecting a possible effect of SCH in lowering the threshold for the emergence of MDD. The relationship between SCH and MDD is, however, not clear, with large and well-designed studies investigating possible links between reference-range thyroid hormone levels and MDD having as yet found no relation between the two.

The intersections of stress, anxiety and epilepsy

Stress is ubiquitous in chronic medical conditions; however, the connections to psychiatric and neurologic conditions are not always clearly established. Epilepsy is a unique illness that is intimately intertwined with stress and anxiety not only as a result of the disease process but also as a cause of disease exacerbation. Anxiety and depression also involve stress management and often overlap with epilepsy. Anxiety symptoms themselves may be present as intrinsic aspects of seizure phenomena, either during the events or closely related to them. The pathways of stress and anxiety involve the hypothalamic pituitary adrenal (HPA) axis and explain at least in part how stress may lead to worsening seizure control. Ultimately, the study of stress, anxiety, and epilepsy offers insight into mind and body connections, and furthers understanding of neuropsychiatric illness.

Chronic psychosocial stress alters NPY system: different effects in rat and tree shrew

The neuropeptide Y (NPY) system has been largely studied in relation to affective disorders, in particular for its role in the mechanisms regulating the pathophysiology of anxiety and depression and in the stress-related behaviours. Although NPY has been previously investigated in a variety of animal models of mood disorders, the receptor subtype mainly involved in the modulation of the stress response has not been identified. In the present study, the chronic psychosocial stress based on the resident-intruder protocol-an ethologically relevant paradigm known to induce behavioural and endocrine modifications which mimic depression-like symptoms-was used. Two different species were investigated: rat and tree shrew (Tupaia belangeri); the latter is regarded as an intermediate between insectivores and primates and it was chosen in this study for its pronounced territoriality. In these animals, the regulation of NPY and of Y(1), Y(2) and Y(5) receptors mRNA expression was evaluated after chronic stress and chronic antidepressant treatment by in situ hybridization in selected brain regions known to be involved in the pathophysiology of mood disorders. The animals were exposed to psychosocial stress for 35 days and concomitant daily fluoxetine treatment (10 mg/kg for rats and 15 mg/kg for tree shrews) after the first week of stress. The results confirmed a major role for hippocampal and hypothalamic NPY system in the pathophysiology of mood disorders. Although there were no evident differences between rat and tree shrew in the NPY system distribution, an opposite effect of chronic psychosocial stress was observed in the two species. Moreover, chronic antidepressant treatment was able to counteract the effects of stress and restored basal expression levels, suggesting the utility of these paradigms as preclinical models of stress-induced depression. Overall, although evident species differences were found in response to chronic psychosocial stress, the present study suggests a role for NPY receptors in the stress response and in the action of antidepressant drugs, providing further support for an involvement of this neuropeptidergic system in the pathophysiology of depression and anxiety.

Internalizing disorders in early childhood: a review of depressive and anxiety disorders

This article reviews the use of the broad category of internalizing disorders and data on young children using this definition. It also reviews the emerging support for more specific internalizing diagnoses in very young children. The current empiric database on nosology and treatment of mood and anxiety disorders in young children is examined, and a clinical case example is included. Identification of recent advances in the understanding and treatment of anxiety disorders in young children and areas in which future studies are needed also are explored.

Icariin from Epimedium brevicornum attenuates chronic mild stress-induced behavioral and neuroendocrinological alterations in male Wistar rats

Chronic mild stress (CMS) is suggested to produce abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis and hypothalamus-pituitary-thyroid (HPT) axis. Therefore, compound that attenuates the neuroendocrinological alterations may have potential as antidepressant. The behavioral and neuroendocrinological effects of icariin, a major constituent of flavonoids isolated from Epimedium brevicornum, were investigated in the CMS model of depression in male Wistar rats. CMS procedure caused an anhedonic state in rats resulted in increased corticotropin-releasing factor (CRF) concentrations in dissected brain regions and serum, decreased total triiodothyronine (tT3) in serum with no significant changes in serum adrenocorticotrophic hormone (ACTH) and thyroxine (tT4). Administration of icariin reversed CMS-induced sucrose intake reduction and CRF elevation. These results suggested that icariin possessed potent antidepressant-like activities which were at least in part mediated by improving the abnormalities in the HPA axis functions. However, we did not find a clear correlation between the HPT axis and icariin treatment in the CMS-treated rats.

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.

Elevated thyroid indices in children and adolescents with obsessive-compulsive disorder: effects of clomipramine treatment

OBJECTIVE

To examine the basal thyroid function in pediatric Obsessive Compulsive Disorder (OCD) versus controls, and to explore the relation between baseline thyroid measures and response to clomipramine treatment, and the effects of treatment on thyroid hormones.

METHODS

Sixteen children and adolescents with DSM-III-R OCE and 13 control children and adolescents without psychiatric illness were compared on basal measures of thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4). For the OCD subjects, samples were compared pre- and post- 4 weeks of treatment with clomipramine. Response of OCD symptoms was measured by the Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS).

RESULTS

OCD subjects demonstrated subtle but significant elevations of TSH, T3, and T4 pre-treatment compared to controls. Clomipramine treatment was associated with significant decreases in TSH and T3 concentrations. Pre-treatment TSH and T4 concentrations correlated with reductions in CY-BOCS following 8 weeks of clomipramine.

CONCLUSION

Elevated thyroid function at baseline may be a biomarker of OCD improvement, and may reflect aspects of the underlying pathophysiology of OCD.

Thyroid and adrenal axis in major depression: a controlled study in outpatients

OBJECTIVE

Major depressive disorder has been associated with changes in the hypothalamus-pituitary-thyroid (HPT) axis and with hypercortisolism. However, the changes reported have been at variance, probably related to in- or outpatient status, the use of antidepressant medication and the heterogeneity of depression. We therefore conducted a controlled study in unipolar depressed outpatients who had been free of antidepressants for at least 3 months.

DESIGN

We assessed endocrine parameters in 113 depressed outpatients and in 113 sex- and age-matched controls.

METHODS

Patients were included if they had a major depression according to a Structural Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (DSM), fourth edition (SCID-IV) and if they had a 17-item Hamilton rating scale for depression (HRSD) score of > or =16. Endocrine parameters contained serum concentrations of TSH, (free) thyroxine, tri-iodothyronine, cortisol, thyroid peroxidase (TPO) antibody titre and 24-h urinary excretion of cortisol.

RESULTS

The serum concentration of TSH was slightly higher in depressed patients as compared with controls (P < 0.001), independent of the presence of subclinical hypothyroidism and/or TPO antibodies (n = 28). All other HPT axis parameters were similar in both groups. The 24-h urinary cortisol excretion was similar in patients and controls. In atypical depression, serum cortisol was lower than in non-atypical depression (P = 0.01). Patients with neither melancholic depression nor severe depression (HRSD > or =23) had altered endocrine parameters. Finally, serum TSH values could not be related to cortisol values.

CONCLUSION

When compared with matched control subjects, outpatients with major depression had slightly higher serum TSH, while urinary cortisol levels were similar. Furthermore, we observed lower serum cortisol in atypical depression than in non-atypical depression.

Decreased pituitary volume in patients with bipolar disorder

BACKGROUND

Neuroendocrinologic investigations in bipolar disorder have suggested abnormalities in pituitary function. However, few imaging studies have evaluated possible anatomical differences in this brain structure in mood disorder patients. Our aim was to examine potential abnormalities in pituitary volume in patients with bipolar and in a comparison group of patients with unipolar disorder.

METHODS

We measured the volumes of the pituitary gland in 23 patients with bipolar disorder (mean +/- s.d. = 34.3 +/- 9.9 years) and 13 patients with unipolar disorder (41.2 +/- 9.6 years), and 34 healthy control subjects (36.6 +/- 9.6 years) using 1.5 mm thick T1-weighted coronal 1.5 T MRI images. All measurements were done blindly by a trained rater.

RESULTS

Patients with bipolar disorder had significantly smaller pituitary volumes than healthy control subjects (mean volume +/- s.d. = 0.55 +/- 0.15 ml and 0.68 +/- 0.20 ml, respectively; ANCOVA, F = 8.66, p = 0.005), and than patients with unipolar disorder (0.70 +/- 0.12 ml, F = 5.98, p = 0.02). No differences were found between patients with unipolar disorder and healthy control subjects (F = 0.01, p = 0.91).

CONCLUSIONS

To our knowledge, this is the first study that reports smaller pituitary volumes in bipolar disorder. Our findings suggest that detectable abnormalities in pituitary size are present in patients with bipolar disorder, which may reflect a dysfunctional HPA axis.

Physiological effects of electroconvulsive therapy and transcranial magnetic stimulation in major depression

Major depressive episodes are associated with dysregulation of various physiologic systems. Antidepressant medications alter regulation of the hormonal and sleep systems. A thorough understanding of these changes may elucidate the pathophysiologic basis of the disorder [Amsterdam et al., 1989: Psychoneuroendocrinology 14:43-62], and interventions targeted directly at these systems are being increasingly recognized as possible treatments for depression [Wong et al., 2000: Proc Natl Acad Sci USA 97:325-330; Szuba et al., 1996: Proc Am Coll Neuropsychopharmacol Ann Meet]. These physiologic systems are regulated by the major neurotransmitters implicated in the etiology of mood disorders--norepinephrine, serotonin, and dopamine. Many of the hormones of import for this article also act as neurotransmitters and thus alter cerebral activity themselves [Owens and Nemeroff, 1993: Ciba Found Symp 172:296-308; Weitzner, 1998: Psychother Psychosom 67:125-132]. Parenteral infusion of hydrocortisone [DeBattista, 2000: Am J Psychiatry 157:1334-1337] and thyrotropin-releasing hormone (TRH) [Prange et al., 1972: Lancet 2:999-1002; Marangell et al., 1997: Arch Gen Psychiatry 54:214-222; Szuba, 1996: Proc Am Coll Neuropsychopharmacol Ann Meet.] produce acute antidepressant effects. Antagonists to corticotropin-releasing hormone and repeated parenteral infusion of TRH may have antidepressant activity when given during several weeks [Wong, 2000: Proc Natl Acad Sci USA 97:325-330; Arborelius et al., 1999: J Endocrinol 160:1-12; Callahan et al., 1997: Biol Psychiatry 41:264-272]. Manipulations of the sleep system through sleep deprivation can ameliorate depression [Szuba et al., 1994: Psychiatry Res 51:283-295; see Wirz-Justice et al., 1999: Biol Psychiatry 46:445-453 for review]. Sleep deprivation has been shown in more than three dozen studies published in the last three decades to produce marked, acute antidepressant effects in the majority of depressed individuals [Wirz-Justice, et al., 1999: Biol Psychiatry 46:445-453]. Thus, examination of the effects the two nonpharmacologic treatments, electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS), produce in these physiologic systems may help elucidate their mechanisms of action, while enhancing understanding of the neurobiology of depressive illness. We will review these physiologic changes associated with depression, the effects that manipulations of these systems can have on depressive disorders, and then describe the effects the two techniques that can stimulate the human brain in vivo, ECT and TMS, exert on these systems.

Hypertension incidence is predicted by high levels of hopelessness in Finnish men

Recent studies have reported that hopelessness is an important factor in cardiovascular morbidity and mortality, including ischemic heart disease, acute myocardial infarction, and atherosclerotic progression. This study examined the relationship between hopelessness and incident hypertension in a population-based sample of 616 initially normotensive, middle-aged men from eastern Finland, an area with high rates of cardiovascular disease. Participants completed a medical examination and a series of psychological questionnaires at baseline and at the 4-year follow-up. Hopelessness was measured by 2 items assessing negative expectancy about the future and one's goals. A logistic regression model with adjustments for age, body mass index, baseline resting blood pressure, physical activity, smoking, alcohol consumption, education, parental history of hypertension, and self-reported depressive symptoms revealed that men reporting high levels of hopelessness at baseline were 3 times more likely to become hypertensive (systolic blood pressure > or =165 mm Hg and/or a diastolic blood pressure > or =95 mm Hg or confirmed use of antihypertensive medication) in the intervening 4 years than men who were not hopeless (odds ratio, 3.22; 95% confidence interval, 1. 56, 6.67). Men reporting moderate levels of hopelessness were not at a significantly increased risk of hypertension (odds ratio, 1.27; 95% confidence interval, 0.79, 2.07). This is the first study to identify a significant relationship between hopelessness and incident hypertension. Research is needed to explore the neuroendocrine and central nervous system mechanisms underlying this association.

Thyrotropin stimulating hormone response to thyrotropin releasing hormone in patients with panic disorder

OBJECTIVE

The aim of this study is to assess thyrotropin stimulating hormone (TSH) response to thyrotropin releasing hormone (TRH) in patients with panic disorder (PD).

METHOD

The effects of TRH administration on the release of TSH were examined in 15 patients who met DSM-III-R criteria for PD and compared their test results with those of 15 normal control subjects. Blood samples were taken before TRH administration (baseline values) and at 15, 30 and 60 min.

RESULTS

delta max TSH values were lower in the panic disorder patients than in the control subjects. Using the criterion of delta max TSH < or = 7 mlU/l, nine of the 15 panic disorder patients and four of the 15 control subjects had a blunted TSH response to TRH.

CONCLUSIONS

These results confirm the findings from earlier reports that patients with PD show blunted TSH response to TRH which is similar to that seen in depressed patients.

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.

Dexamethasone response, thyrotropin-releasing hormone stimulation, rapid eye movement latency, and subtypes of depression

Most prior studies of mood disorders have used a single laboratory test to assist in differential diagnosis, prediction of treatment response, and prediction of relapse. This study compared three laboratory measures in a combined in- and outpatient sample of depressed patients. Dexamethasone suppression test (DST) nonsuppression occurred in 46% of patients with endogenous major depression, in 15% with nonendogenous major depression, and in 56% with bipolar, depressed phase disorder. A blunted thyrotropin-releasing hormone stimulation test (TRH-ST) occurred in 25% of patients with endogenous, 10% with nonendogenous, and 44% with bipolar, depressed phase disorder. Reduced REM latency was found in 65% of endogenous major depressions, in 34% of nonendogenous major depressions, and in 53% of bipolar, depressed phase disorders. Fifty-one percent of those with reduced REM latency also evidenced DST nonsuppression. When the endogenous major depression and bipolar, depressed phase groups were combined, 28% had no laboratory abnormality, whereas 8% evidenced all three. These findings suggest that 1) endogenous/nonendogenous unipolar groups are distinguished by all three laboratory tests; 2) most patients with a blunted TRH-ST also evidence DST nonsuppression; and 3) one half of patients with reduced REM latency evidence DST nonsuppression. Sensitivity is greatest and specificity is lowest for REM latency, followed by the DST and then the TRH-ST.

Circadian rhythms of prolactin and thyroid-stimulating hormone during the menstrual cycle and early versus late sleep deprivation in premenstrual dysphoric disorder

The present study extended previous work by examining whether disturbances in the circadian rhythms of prolactin (PRL) and thyroid-stimulating hormone (TSH) distinguish patients with premenstrual dysphoric disorder (PMDD) from normal volunteers. In addition, the effects of therapeutic interventions with early and late partial sleep deprivation were explored. Both PRL and TSH levels were measured every 30 min from 18:00 h to 09:00 h during midfollicular and late luteal menstrual cycle phases in 23 PMDD patients and 18 normal volunteers. Hormone levels were measured again after a randomized crossover trial of early (sleep 03:00-07:00 h) versus late (sleep 21:00-01:00 h) partial sleep deprivation administered in two separate luteal phases. Compared with normal volunteers, PMDD patients had higher PRL concentrations, consistent with previous findings. TSH rhythms occurred earlier in PMDD than in normal subjects. PRL levels decreased and TSH levels increased with sleep deprivation compared with baseline conditions. The timing of PRL secretion shifted earlier with late sleep deprivation and later with early sleep deprivation. Although circadian disturbances of PRL and TSH were found in PMDD patients compared with normal volunteers, the therapeutic effects of early and late sleep deprivation do not appear to be mediated by correcting these disturbances.

Sensitive assay of thyroid stimulating hormone in depressed patients

A decreased thyroid stimulating hormone (TSH) response to thyrotropin releasing hormone (TRH) has been noted in major depression. Some authors found a positive correlation between baseline TSH levels and TSH response to TRH, especially with sensitive assays of TSH. Serum TSH was assayed by a sensitive method in 55 depressed patients and 38 healthy volunteers. Patients were subclassified according to DSM-III as suffering from major depression (n = 40) and non-major depression (n = 15). The patients' mean score on the Hamilton Rating Scale for Depression (HRSD) was 50 (SD = 10). The TSH value was significantly lower in depressed patients compared with healthy control subjects, and in major compared with non-major depression. No differences in TSH levels distinguished the various subtypes of major depression. There was a significant negative correlation between global HRSD scores and TSH concentrations. The most anxious patients tended to have significantly lower TSH values compared with the least anxious subjects. Total HRSD insomnia scores correlated negatively with TSH concentrations after log transformation. The sensitive determination of TSH may also provide an index of thyroid function in depression that is simpler to implement than measurements of the TSH response to TRH.

High prevalence of thyroid function test abnormalities in chronic schizophrenia

The thyroid status of 249 patients with chronic schizophrenia (males = 136, females = 113) with a median age of 36 years (range: 16 to 58 years) and a median duration of hospitalisation of 10 years (range: 1 to 30 years) was assessed. Thyroid antibodies (TAb) were found in 51 patients (20%). In female patients, 32 (28%) were TAb positive compared to 13% (n = 152, p = 0.01) in healthy female blood donors. In male patients, the prevalence of TAb was 14% compared to 7% (n = 449, p = 0.01) in healthy male blood donors. Of the 183 patients who had thyroid hormone measurements, 60% had normal test, 5% had elevated TSH and 17% had low TSH. The T4, FT41 and FT31 were significantly lower in those with low or high TSH (p < 0.001) compared to those with normal TSH. Of the 143 patients with normal TSH, 33 (23%) had low T3. In conclusion, there is a spectrum of thyroid function test abnormalities in chronic schizophrenia; this may be related to an abnormality in the central regulation of the hypothalamo-pituitary thyroid axis as well as at the peripheral level. However the association between chronic schizophrenia and the presence of thyroid antibodies, and the clinical relevance of these biochemical abnormalities, are still not clear.

Thyrotropin response to TRH stimulation in depressed patients with autoimmune thyroiditis

Two thyroid axis findings are often reported in depressed patients: autoimmune thyroiditis and abnormal thyrotropin (thyroid stimulating hormone, TSH) responses to thyrotropin-releasing hormone (TRH). The TSH response to TRH can be exaggerated, suggesting subclinical hypothyroidism; it can alternatively be blunted, for reasons poorly understood. We selected 28 women who had been found to have major depression for TRH testing. Fifteen patients had autoimmune thyroiditis and 13 had diffuse nontoxic goiter. The endocrinological diagnoses were verified by fine-needle aspiration biopsy and cytological assessment. Patients with overt hypothyroidism and hyperthyroidism were excluded from the study. There were no differences between the two groups in total triiodthyronine and thyroxine plasma levels or severity of depression. In the autoimmune group, basal TSH and Dmax TSH tended to be higher (p < 0.1); peak TSH was significantly higher (p < 0.05), suggesting that the prevalence of subclinical hypothyroidism was also higher. Blunted TSH responses were found about as often in one group as the other.

Subclinical hypothyroidism resulting from autoimmune thyroiditis in female patients with endogenous depression

Thyroid function and presence of thyroid autoantibodies were assessed in a group of 75 consecutive female patients with mood disturbances and in a group of 38 healthy women of similar age recruited as controls. Nine patients suffered from major (endogenous) depression and 66 from minor (neurotic) depression. The individual patients had normal values of circulating thyroid hormones. Nevertheless, endogenously depressed patients had total serum triiodothyronine (M +/- SE = 1.49 +/- 0.09 nmol/l) and both total (83.9 +/- 4.3 nmol/l) and free serum thyroxine (13.9 +/- 1.1 pmol/l) lower than in the group of minor depressed and in the group of controls (p < 0.01, in both comparison). The median value of serum thyrotropin was 5.22 mU/l in the major depressed patients versus 1.72 mU/l in the minor depressed and 1.69 mU/l in the controls. Thyroid function test results in the minor depressed group did not significantly differ from those in the controls. Five of the 9 endogenously depressed patients were subclinically hypothyroid, while none of the 66 patients with minor depressive disorder showed thyroid dysfunction. Antibodies against thyroglobulin and/or thyroid peroxidase were positive in all the 5 endogenously depressed women with subclinical hypothyroidism, revealing a symptomless autoimmune thyroiditis, which was also confirmed by ultrasonography in all cases and histopathologically demonstrated in one case. None of the endogenously depressed women without thyroid dysfunction and none of the 66 minor depressives were seropositive for thyroid autoantibodies.(ABSTRACT TRUNCATED AT 250 WORDS)

Lack of seasonal variation in abnormal TSH secretion in patients with seasonal affective disorder

The circadian variations in thyroid-stimulating hormone (TSH) secretion, with particular attention to the nocturnal serum TSH surge and the TSH response to thyrotropin releasing hormone (TRH), were measured in seven patients with seasonal affective disorder (SAD) and in eight normal controls. Both patients with SAD and normal controls were tested in fall/winter, when patients were suffering depressive symptoms, and in spring/summer, when patients were euthymic. The TRH tests were performed in the morning. In all tests, the mean peak TSH response to TRH was significantly lower in the patients with SAD than in the normal controls. No significant differences were observed in either group between spring/summer and fall/winter tests. At both periods, patients with SAD showed normal TSH levels in the morning, but did not experience a nocturnal TSH surge. In this group, morning and night TSH levels were similar. In contrast, normal controls showed significantly higher TSH levels at night than in the morning. Serum-free thyroid hormone levels were in the normal range in all subjects. Morning and night serum cortisol levels and 24-hour urinary cortisol concentrations were similar in all subjects. These data show that the secretion of TSH is impaired in SAD, regardless of the phase of the psychiatric disease. The low TSH response to TRH in the presence of normal serum thyroid hormone levels and the lack of the TSH nocturnal surge suggest that patients with SAD might be affected by mild central hypothyroidism.

Blunted TSH and unaltered PRL responses to TRH following repeated administration of TRH in neurologic patients: a replication of neuroendocrine features of major depression

A blunted thyrotropin (TSH) and an unaltered prolactin (PRL) responses to thyrotropin-releasing hormone (TRH) are widely recognized in neuroendocrinology of depression. We studied effects of repeated TRH administration of 1 mg/day for 10 days on the pituitary-thyroid axis function and PRL secretion in 16 euthyroid patients with neurological disorders. Although levels of serum thyroid hormones and of nonstimulated PRL were not affected by the treatment, baseline TSH levels were markedly inhibited. A blunted response of TSH to TRH was found without a significant effect on a PRL response to TRH after long-term treatment with TRH in four patients in whom a TRH test was performed. These changes are similar to those in depressed patients. TRH administration in this manner replicates a lowered sensitivity of thyrotrophs of the pituitary with a normal responsibility of lactotrophs in depression.

[Ultrasensitive TSH and thyroliberin test in patients hospitalized for depression]

In this prospective study of 35 patients hospitalized for depression, TSH levels were measured before and after stimulation by TRH. The type of depression was determined and its intensity was evaluated by means of the HARD scale. Subjects with systemic disease or receiving treatments known as being likely to influence TSH levels had been excluded. In none of these 35 patients was the TSH level below the lower limit of normal values, nor was there any blunting of response to TRH. These results suggest that depression is not a cause of TSH fall and that a low TSH level with normal hormonaemia must call for scintiscanning, even in depressed subjects.

Neuroendocrine aspects of primary endogenous depression. X: Serum growth hormone measures in patients and matched control subjects

To determine the extent of dysregulation of growth hormone (GH) secretion in endogenous depression, we measured nocturnal serum GH concentrations and GH responses to thyrotropin-releasing hormone (TRH, gonadotropin-releasing hormone (LHRH), and dexamethasone administration in 40 Research Diagnostic Criteria primary, definite endogenous depressives and 40 individually matched normal control subjects. Compared with their controls, the patients showed no difference in basal nocturnal GH concentrations or in GH responses to TRH or LHRH. The GH measures were not significantly related to the other endocrine measures reported previously, including dexamethasone suppression test status. None of the diagnostic schemes for endogenous/melancholic depression which we studied was significantly related to the GH measures in the patients. Of the other subject and symptom variables, the mood depression factor of the Hamilton depression scale and the performance difficulty factor of the Beck depression inventory were moderately negatively correlated with the nocturnal GH measures. These findings suggest that, in contrast to the previously reported hypothalamopituitary-adrenal cortical and thyroid axis abnormalities in our patients, GH secretion was relatively normal. Patients with more severe depressed mood and greater difficulty accomplishing tasks did have moderately lower nocturnal GH values.

Thyrotropin and prolactin responses to protirelin (TRH) prior to and during chronic imipramine treatment in patients with panic disorder

The effects of protirelin [thyrotropin-releasing hormone (TRH)] administration on the release of thyrotropin (TSH) and prolactin (PRL) were examined in 14 patients with panic disorder prior to and during chronic treatment with imipramine. During imipramine treatment, the patients exhibited an increase in their TSH response to TRH (delta delta max TSH = 3.65 +/- 6.02 mu IU/ml, p less than 0.05) and in their PRL response to TRH (delta AUCPRL = 734 +/- 965 ng/ml/45 min, p less than 0.005). Several behavioral measures correlated with the neuroendocrine measures during imipramine therapy. These preliminary findings might suggest a role for changes in dopaminergic function in the clinical effects of imipramine in patients with panic disorder.

Osteoporosis with pathologic hip fractures in major depression

Osteoporosis and its sequelae have been associated with genetic predisposition, aging, nutritional factors, inactivity, substance abuse, and anorexia nervosa. We report three cases of pathologic osteoporotic hip fractures in elderly females with major depression. Biological consequences of depression and mobilization during hospital treatment are discussed as possible mediators of osteoporotic morbidity.

Pharmacoendocrinology of major depression

Major depressives often have abnormalities in the secretion patterns of their anterior pituitary hormones and target endocrine gland hormones. There are changes in both basal hormone secretion and the responses of these hormones to perturbation tests. Considerable work has been done attempting to develop a clinical application for some of these changes as biological state markers of endogenous depression. Prominent among the changes is an overactivity of the hypothalamo-pituitary-adrenocortical (HPA) axis. The dexamethasone suppression test (DST), as a reflection of HPA axis activity, has been the most thoroughly investigated "biological test" in psychiatry to date. Considerably fewer studies have addressed more fundamental issues of HPA axis regulation in depression, such as the relationship between pre-DST cortisol hypersecretion and DST outcome. The next most widely investigated endocrine axis in depression has been the hypothalamo-pituitary-thyroid (HPT) axis. Most studies have dealt with the TSH response to exogenously administered thyrotropin releasing hormone. While blunted TSH responses have been found in depressives compared with normal controls, the frequency of blunted responses in other types of psychiatric patients has made this test marginally useful for differential diagnosis. The reported changes in other hormone axes, for example the blunted growth hormone response to several challenges noted in depressed patients, have not been investigated sufficiently thoroughly to support their general clinical use at present.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuroendocrine aspects of primary endogenous depression. V. Serum prolactin measures in patients and matched control subjects

To ascertain the extent of dysregulation of prolactin (PRL) secretion in endogenous depression, we determined nocturnal serum PRL concentrations and PRL responses to thyrotropin-releasing hormone (TRH), gonadotropin-releasing hormone (LHRH), and dexamethasone administration in 40 Research Diagnostic Criteria (RDC) primary, definite endogenous depressives and 40 individually matched normal control subjects. Compared to their matched controls, the patients showed no difference in basal nocturnal PRL concentrations, a marginally significant 20%-25% increase in the PRL response to TRH, and no differences in post-LHRH or postdexamethasone PRL concentrations. In the patients, there was a weak, negative correlation between age and PRL (r = -0.30), but none of the other subject characteristics or specific dimensions of depressive symptomatology were significantly related to the PRL measures. The PRL measures also were unrelated to pre- and postdexamethasone cortisol concentrations and to the thyrotropin (TSH) responses to TRH in both groups of subjects. In contrast to the previously reported hypothalamo-pituitary-adrenal cortical and thyroid axis abnormalities in these patients, our findings suggest that PRL secretion was relatively normal.

Neuroendocrine aspects of primary endogenous depression VIII. Pituitary-gonadal axis activity in male patients and matched control subjects

To determine the extent of hypothalamo-pituitary-gonadal (HPG) axis dysfunction in endogenous depressed men, we measured nocturnal and diurnal serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T), and estradiol (E2) concentrations, and their responses to gonadotropin releasing hormone (LHRH) and dexamethasone administration, in 16 Research Diagnostic Criteria primary, definite endogenous male depressives and 16 individually matched male normal controls. Compared to their controls, the patients showed no differences in basal nocturnal or diurnal gonadotropin or gonadal steroid hormone concentrations, and no differences in hormone concentrations either post-LHRH or post-dexamethasone. Age was negatively correlated with baseline serum T in the patients but not in the controls, and it was modestly positively correlated with baseline serum LH in both groups of subjects. In the patients, the presence of DSM-III melancholia was modestly negatively correlated with baseline and post-LHRH concentrations of both LH and FSH and was positively correlated with baseline serum T, but it bore no relation to serum E2. None of the other subject characteristics or specific dimensions of depressive symptomatology were significantly related to the HPG axis measures. The HPG axis measures also were unrelated to pre- and post-dexamethasone cortisol concentrations in both groups of subjects. The results of this study suggest that, in contrast to the hypothalamo-pituitary-adrenal cortical and thyroid axis abnormalities frequently found in endogenous depressives, HPG axis function in male depressives is relatively normal.

Neuroendocrine aspects of primary endogenous depression. VII. Logistic regression analysis of matched patient-control hormone data for discrimination between groups

We previously reported significant alterations in hypothalamo-pituitary-adrenal cortical (HPA) and thyroid (HPT) axis function in a group of 40 primary, RDC definite endogenous depressives compared to 40 individually matched normal control subjects. In those reports, univariate statistical tests for matched samples were used (paired t-tests). We next wished to use both the HPA and the HPT measures in a multivariate analysis to discriminate the patients from the controls, but the paired nature of the hormone data obviated the use of standard techniques. With an adaptation of the BMDP PLR statistical program, we performed a matched logistic regression analysis, in stepwise fashion, which resulted in a model incorporating two HPA variables and one HPT variable. From this model, odds ratios which associate being depressed or not with levels of the HPA and HPT measures were estimated. The median odds ratio for the 40 matched pairs was 7.8. To illustrate the model, we present graphs of estimated odds ratios of patients with selected hormone values compared to a typical normal subject with hormone values close to the median values of the 40 controls in our study.