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R T Rubin

Publications and source records attributed to R T Rubin.

At least 73 records · Page 4Linked to original sources

Neuroendocrine aspects of primary endogenous depression. I. Cortisol secretory dynamics in patients and matched controls.

To examine both predexamethasone and postdexamethasone cortisol measures in depression, we determined circadian serum cortisol patterns, cortisol responses to dexamethasone, and 24-hour urinary free cortisol excretion before and after dexamethasone administration in 40 patients with primary, definite endogenous depression diagnosed by Research Diagnostic Criteria and in 40 individually matched normal control subjects. Fifteen patients (38%) were dexamethasone nonsuppressors; they had significantly higher predexamethasone serum and urine cortisol measures than both their matched controls and the 25 suppressor patients. Both the predexamethasone and postdexamethasone cortisol measures were unimodally distributed across the patients and the controls. Circadian cortisol rhythms of similar magnitude occurred in both groups. The cortisol measures before and after dexamethasone administration were positively correlated to a similar degree in the patients and their controls, suggesting that predexamethasone hypothalamic-pituitary-adrenocortical hyperactivity and postdexamethasone cortisol nonsuppression are not independently determined in endogenous depression.

Adult↗

Neuroendocrine aspects of primary endogenous depression. II. Serum dexamethasone concentrations and hypothalamic-pituitary-adrenal cortical activity as determinants of the dexamethasone suppression test response.

To determine the contribution of serum dexamethasone concentrations and hypothalamic-pituitary-adrenal cortical activity before dexamethasone administration to the dexamethasone suppression test (DST) response, a series of stepwise discriminant function analyses were performed for 40 patients with definite endogenous depression and 40 matched normal control subjects. The 24-hour serum cortisol concentration before dexamethasone administration and the serum dexamethasone concentrations at 8, 16, and 24 hours after administration served as the independent variables, and the DST "escaper"/"suppressor" dichotomy served as the dependent variable. While both types of independent variables significantly influenced the DST response, the major factor that contributed to the discrimination of escapers from suppressors was the 24-hour cortisol concentration before dexamethasone administration. Sixteen hours after dexamethasone administration, when the DST had the highest positive predictive value, serum dexamethasone concentrations significantly influenced DST outcome only when they were below a certain threshold level. At this time, hypothalamic-pituitary-adrenal cortical hyperactivity before dexamethasone administration accounted for approximately two thirds of the incidence of DST nonsuppression.

Circadian Rhythm↗

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

In order to ascertain the extent of hypothalamo--pituitary--thyroid (HPT) axis dysfunction in endogenous depression, we determined nocturnal serum thyrotropin (TSH) concentrations, TSH responses to thyrotropin releasing hormone (TRH) administration, and serum triiodothyronine (T3) and thyroxine (T4) concentrations in 40 Research Diagnostic Criteria primary, definite endogenous depressives and 40 individually matched normal control subjects. We also examined the relationships of the HPT measures to pre- and post-dexamethasone (DEX) serum and urine cortisol measures and, in the patients, to subject characteristics, the diagnosis of endogenous/melancholic depression by different systems, and the overall severity and specific dimensions of depressive symptomatology. Compared to their matched controls, the patients showed significant reductions in nocturnal serum TSH and serum T3 concentrations. Neither the TSH responses to TRH nor serum T4 concentrations were significantly different between the two groups of subjects. In the patients, none of the subject characteristics, diagnostic schemes for endogenous/melancholic depression or specific aspects of depressive symptomatology were significantly related to HPT activity. The measures of HPT activity were unrelated to measures of hypothalamo--pituitary--adrenal cortical (HPA) axis activity in both groups of subjects.

Adult↗

Neuroendocrine aspects of primary endogenous depression. III. Cortisol secretion in relation to diagnosis and symptom patterns.

In order to ascertain the extent of hypothalamo-pituitary-adrenal cortical (HPA) hyperactivity in endogenous depression, we determined circadian serum cortisol patterns, cortisol responses to dexamethasone (DEX) administration, and urine free cortisol excretion before and after DEX administration in 40 definite endogenous depressives diagnosed with the Research Diagnostic Criteria. The cortisol measures ranged from normal to clearly elevated. To elucidate the clinical correlates of these hormone measures in the patients, we examined the relationships of the pre- and post-DEX cortisol measures to the diagnosis of endogenous/melancholic depression by different systems and to the overall severity and specific dimensions of depressive symptomatology. In this group of endogenous depressives, none of the diagnostic schemes for endogenous/melancholic depression which we studied was significantly related to the pre- or post-DEX cortisol measures. Of the other subject and symptom variables, only age and the agitation/anxiety factor of the Hamilton depression scale shown consistent relationships with the cortisol measures. Both were positively correlated, to a moderate degree, with the hormone measures, and they were not correlated with each other. Together they explained approximately 20% of the variance in the cortisol measures. Thus, within a group of moderately to severely ill endogenous depressives, the older and the more agitated anxious patients have a significantly greater likelihood of showing increased HPA activity. These findings indicate that age should be controlled in studies of the HPA axis and that the subjective experience of anxiety may contribute to HPA hyperactivity in endogenous depression.

Adult↗

Past and current thyroid function in subjects with panic disorder.

Disturbances in thyroid function can result in symptoms similar to those occurring in patients with anxiety disorders, especially panic disorder. An association between thyroid illness and panic and phobic disorders has been suggested, but few studies have directly investigated this issue. To assess this possible relationship, the authors measured indices of thyroid function in 165 subjects who had a current DSM-III diagnosis of panic disorder, either with or without phobic avoidance. These subjects reported a higher prevalence of thyroid illness by history compared with the prevalence of thyroid illness in the general population; however, less than 1% of all subjects had current thyroid dysfunction. The presence of a major depressive episode (MDE) was unrelated to current thyroid function, although subjects with MDE reported a higher prevalence of thyroid disease by history. Indices of thyroid function were not correlated with the severity of panic attacks or phobias.

Adult↗

Plasma growth hormone response to insulin-induced hypoglycemia in infantile autism: a pilot study.

Plasma growth hormone responses to insulin-induced hypoglycemia were examined in eight preschool-age autistic children. Six of these children were examined on two separate occasions: during the period of baseline evaluation and after 4 weeks of daily haloperidol administration. On at least one occasion, half of this small sample exhibited persistent elevation of growth hormone levels, with a failure to return to baseline values over the course of a 135-minute period postinsulin infusion. These data are consistent with the occurrence of hypothalamic dysfunction in subgroups of autistic children. Short-term administration of haloperidol did not diminish the ability of the pituitary to secrete growth hormone in response to insulin-induced hypoglycemia.

Autistic Disorder↗

More on DST.

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Depressive Disorder↗

Diagnostic considerations in panic disorders.

Approaches to the classification and treatment of anxiety have been lacking because of the unclear borders between pathologic and normal anxiety and the heterogeneity of patients called "anxious." The differentiation of panic from other anxiety states is a recent development in psychiatric nosology. The diagnosis of panic disorder and agoraphobia and their demarcation from other psychiatric and medical disorders are reviewed. Proposals to revise DSM-III criteria to provide concordance with current etiologic theories are discussed, and an overall treatment strategy that takes into account the multiple manifestations of the illness is outlined.

Agoraphobia↗

A modified dexamethasone suppression test for endogenous depression.

In order to simplify the dexamethasone suppression test (DST), we have administered a lower dosage of dexamethasone (DEX) and shortened the sampling time to a single morning blood sample. DEX (in dosage increments from 0.125 to 1.0 mg, p.o.) was administered at 2300 h to normal volunteers in a double-blind randomized fashion, and blood samples were taken at 0700 h the following morning. While significant cortisol suppression occurred after the 0.375 mg, 0.5 mg, and 1.0 mg doses of DEX, the 0.5 mg dose was the smallest that clearly suppressed cortisol in all eight subjects. This dose then was used to test the feedback sensitivity of the central nervous system (CNS)-pituitary-adrenal axis in endogenously depressed patients. Twenty endogenously depressed patients and 20 normal volunteers were given both the standard 1.0 mg DST, with post-DEX serum cortisol determined at 1500 h, and the simplified 0.5 mg DST, with post-DEX serum cortisol determined at 0700 h. Four patients (20%) and one control (5%) were nonsuppressors after the 1.0 mg DST, and nine patients (45%) and one control (5%) were nonsuppressors after the 0.5 mg DST. In addition, nine patients with major depression (nonendogenous subtype) and 15 patients with panic attacks also were studied using the 0.5 mg DST. Only 2 of these 24 patients (8%) were nonsuppressors. The results suggest that the single-sample 0.5 mg DST is more sensitive than the standard 1.0 mg DST, and the specificity of the modified test appears comparable to the standard form of the test.

Adult↗

Pre- and post-dexamethasone salivary cortisol concentrations in major depression.

Seventy patients fulfilling DSM-III criteria for major depression were given the 1.0 mg overnight dexamethasone suppression test, with salivary cortisol concentrations being measured as the dependent variable. Using both the DSM-III and the Research Diagnostic Criteria, we categorized the patients into four groups based on increasing frequency of endogenous symptomatology. Among these four groups there were no significant differences in salivary cortisol concentrations either before dexamethasone or eight, 16, and 24 h after dexamethasone. Similarly, there were no significant differences among the groups in either the ratios of post- to pre-dexamethasone salivary cortisol or the frequencies of positive tests based on several criterion levels of cortisol for the three post-dexamethasone samples. Multiple regression analyses indicated that the Hamilton depression rating scale item "somatic anxiety" was significantly negatively related to post-dexamethasone cortisol concentrations. We conclude that, for our sample of major depressives, the salivary cortisol dexamethasone suppression test showed no utility as a laboratory correlate of depressive episodes with endogenous features.

Adult↗

Plasma prolactin and severe premenstrual tension.

It has been suggested that elevated luteal phase prolactin (PRL) levels may have an important role in causing some of the symptoms of the premenstrual tension syndrome (PMTS). Thirty-seven women suffering from severe premenstrual dysphoria were selected for this study. Single morning and afternoon serum PRL evaluations were performed during the follicular (day 9) and late luteal (day 26) phases of the menstrual cycle. PRL was measured by an established double antibody radioimmunoassay technique. All mean PRL values were within the normal range. Only afternoon mean PRL levels showed a tendency for a premenstrual increase. The significance of this statistical finding is unclear, since one-third of the subjects showed a decrease in premenstrual PRL levels. Twenty-four hour PRL secretory profiles recorded on days 9 and 26 in two women with extremely severe PMTS and in two asymptomatic matched control subjects also failed to show a significant correlation between PRL levels and PMTS. Thirty subjects participated in a treatment trial using bromocriptine. A marked rebound hyperprolactinemia was observed in a subgroup of women nine days after cessation of bromocriptine. This was associated with no detectable effect on mood, behavior, or menstrual regularity. Thus, our data fail to show any specific relationship between PRL and PMTS.

Adult↗

Circadian hormone secretory profiles in women with severe premenstrual tension syndrome.

The circadian secretory profiles of serum prolactin, growth hormone and cortisol were measured in two women suffering from severe premenstrual tension syndrome and in two asymptomatic control subjects. Subjects and controls were screened and included after a rigorous selection process. Blood samples were obtained every 30 min over a period of 24 h in each woman both on day 9 (follicular phase) and day 26 (luteal phase) of the menstrual cycle. There was no relationship between the hormonal secretory profiles and the premenstrual tension syndrome.

Adult↗

Situational depression and the dexamethasone suppression test.

Neither baseline integrated 24 hr cortisol concentrations nor cortisol escape from dexamethasone suppression were able to distinguish a group of endogenously depressed patients who experienced precipitating events prior to their depression (situational) from a group of endogenously depressed patients with no discernible precipitating events (non-situational). Symptom severity, features of psychosis, and family history also were similar between the two groups. These results highlight the inadequacy of using the presence or absence of precipitating events for subtyping endogenous depression.

Adjustment Disorders↗