Biomedical subjects

M A Oquendo

Publications and source records attributed to M A Oquendo.

At least 19 recordsLinked to original sources

PubMed2006

Prospective studies of suicidal behavior in major depressive and bipolar disorders: what is the evidence for predictive risk factors?

OBJECTIVE: Prospective studies over the past 30 years have identified an array of predictive indicators for suicidal acts in mood disorders. However, prediction of suicidal behavior remains an elusive goal. This paper reviewed evidence from prospective studies for clinical factors that elevate risk of suicidal acts in that group. METHOD: English language prospective studies of suicidal behavior in major depressive and bipolar disorders were examined. RESULTS: The predictors with the best support were a past history of suicidal behavior and the presence of refractory or recurrent depressions. For other risk factors, there was either not enough data to consider them robust or findings were contradictory. CONCLUSION: Future studies must not only be comprehensive in their inclusion of potentially contributing factors, but must also address their relative importance towards the goal of developing predictive models and enhance suicide prevention efforts.

Bipolar Disorder↗

PubMed2005

Clinical features of depressed patients with or without a family history of alcoholism.

OBJECTIVE: To compare clinical features of depressed subjects without alcoholism but with a family history of alcoholism to a depressed group without alcoholism and without a family history of alcoholism. METHOD: Clinical and demographic data of 209 depressed subjects without a history of alcoholism in first-degree relatives and 73 depressed individuals with a history of alcoholism in first-degree relatives were compared. Subjects with a personal history of alcoholism were excluded. RESULTS: Depressed subjects with a family history of alcoholism have a significantly higher prevalence of reported childhood physical and sexual abuse and post-traumatic stress disorder (PTSD), make more suicide attempts, and have greater intent to die at the time of their most lethal suicide attempt, compared to depressed subjects without a family history of alcoholism. CONCLUSION: Depressed patients with a family history of alcoholism are at greater risk for suicidal behavior and PTSD and may require more careful management.

Adult↗

PubMed2004

Rates of lifetime suicide attempt and rates of lifetime major depression in different ethnic groups in the United States.

OBJECTIVE: Rates of major depression and suicide vary across ethnic groups within the US. This also may be true of suicide attempts. METHOD: Data on lifetime suicidal behavior and major depression among Mexican American, Cuban American, and Puerto Rican adults who participated in the Hispanic Health and Nutrition Epidemiologic Survey were pooled with Epidemiological Catchment Area Study data for Blacks, Whites and Hispanics. RESULTS: Rates of major depression ranged from 9.3 (Puerto Ricans) to 3.24% (Cuban Americans). Puerto Ricans and whites had the highest rates of depression. Similarly, suicide attempt rates ranged from 9.1% for Puerto Ricans to 1.9% for Cuban Americans. Puerto Ricans had higher suicide attempt rates compared with other groups. CONCLUSION: This study underscores that there are differences between Hispanic ethnic groups. The impact of the migration process, socioeconomic status, and acculturation may underlie differences in major depression and suicide attempt rates across ethnic groups.

Adult↗

PubMed2002

Lower cortisol levels in depressed patients with comorbid post-traumatic stress disorder.

Post-traumatic stress disorder (PTSD) is often comorbid with major depressive episodes (MDEs) and both conditions carry a higher rate of suicidal behavior. Hypothalamic-pituitary-adrenal (HPA) axis and serotonin abnormalities are associated with both conditions and suicidal behavior, but their inter-relation is not known. We determined cortisol response to placebo or fenfluramine in MDE, MDE and PTSD (MDE+PTSD), and healthy volunteers (HVs) and examined the relation of cortisol responses to suicidal behavior. A total of 58 medication-free patients with MDE (13 had MDE+PTSD) and 24 HVs were studied. They received placebo on the first day and fenfluramine on the second day. Cortisol levels were drawn before challenge and for 5 h thereafter. The MDE+PTSD group had the lowest plasma cortisol, the MDE group had the highest, and HVs had intermediate levels. There were no group differences in cortisol response to fenfluramine. Suicidal behavior, sex, and childhood history of abuse were not predictors of baseline or postchallenge plasma cortisol. Cortisol levels increased with age. This study finds elevated cortisol levels in MDE and is the first report of lower cortisol levels in MDE+PTSD. The findings underscore the impact of comorbidity of PTSD with MDE and highlight the importance of considering comorbidity in psychobiology.

Adult↗

PubMed2001

Aggressivity, suicide attempts, and depression: relationship to cerebrospinal fluid monoamine metabolite levels.

BACKGROUND: We have proposed a stress-diathesis model for suicidal behavior, in which major depression is a stressor and the diathesis is shared with aggression. Neurotransmitter correlates of the stress or diathesis have not been adequately evaluated by previous studies, because they did not simultaneously examine the relationship of multiple neurotransmitters to all three psychopathologies in the same population. In the present study we investigated the relationship of monoamine metabolites to aggressivity, suicidal behavior, and depression in patients with mood disorders. METHODS: Ninety-three drug-free subjects with a major depressive episode underwent lumbar puncture and psychiatric evaluation. Cerebrospinal fluid CSF levels of 5hydroxyindolacetic acid (5-HIAA), homovanillic acid (HVA) and methoxy-hydroxy-phenylglycol (MHPG) were assayed. The relationships between monoamine metabolites and clinical variables were statistically evaluated. RESULTS: Higher lifetime aggressivity correlated significantly with lower CSF 5-HIAA. Lower CSF 5-HIAA and greater suicidal intent were found in high-lethality suicide attempters compared with low-lethality suicide attempters. Low-lethality attempters did not differ biologically from nonattempters. No correlation between CSF HVA and any of the psychopathological variables was found. Only aggression showed a trend statistically in correlating positively with CSF MHPG levels. CONCLUSIONS: Lower CSF 5-HIAA concentration was independently associated with severity of lifetime aggressivity and a history of a higher lethality suicide attempt and may be part of the diathesis for these behaviors. The dopamine and norepinephrine systems do not appear to be as significantly involved in suicidal acts, aggression, or depression. The biological correlates of suicide intent warrant further study.

Adult↗

PubMed2001

Dopamine D(2) receptor availability and amphetamine-induced dopamine release in unipolar depression.

BACKGROUND: Reduced dopaminergic transmission has been implicated in the pathophysiology of major depression. The aim of the present study was to measure striatal D(2) receptor availability and amphetamine-induced dopamine release in nonpsychotic, unmedicated, unipolar patients during an episode of major depression. METHODS: The striatal equilibrium specific to nonspecific partition coefficient (V(3)") of the D(2) receptor antagonist [(123)I]IBZM was measured with single photon emission computerized tomography before and after amphetamine administration in 9 depressed subjects and 10 matched healthy control subjects. RESULTS: No significant differences were observed in preamphetamine D(2) receptor availability between depressed patients (0.73 +/- 0.08) and control subjects (0.78 +/- 0.10, p =.23). Amphetamine-induced reduction in [(123)I]IBZM V(3)" (DeltaV(3)") was similar in depressed patients (-9.8 +/- 5.5%) and control subjects (-7.8 +/- 2.5%, p =.32). Amphetamine induced a transient improvement in symptomatology in depressed patients, but this improvement did not correlate with [(123)I]IBZM DeltaV(3)". CONCLUSIONS: This study did not replicate previously reported alterations in striatal D(2) receptor density in depressed patients and suggests that stimulant-induced dopamine release is not altered in major depression.

Adolescent↗

PubMed2001

Understanding the neurobiology of suicidal behavior.

Our current knowledge about the neurobiology of suicide is still limited. Technical limitations and the complexity of the CNS are major obstacles. However, there is evidence for a hereditary disposition to suicide, which appears to be independent of diagnosis. Clinical, postmortem, genetic, and animal studies suggest that serotonin has a central role. The main regions of interest in the CNS have been the dorsal and median raphe nuclei in the midbrain that host the main serotonergic cell bodies and the prefrontal cortex, particularly the ventral PFC, innervated by the serotonergic system. In vivo and postmortem studies indicate serotonergic hypofunction in suicide and serious suicide attempts. This deficiency in turn can lead to a predisposition to impulsive and aggressive behavior, probably due to a breakdown in the inhibitory function of the ventral prefrontal cortex as a result of less serotonin input. In the context of this predisposition and the development of mental illness or other life stressors, the individual is at risk of acting on suicidal thoughts. Such deficient serotonin input into the PFC may arise as a result of genetic, parenting, head injury, and other effects. Identifying psychiatric, social, and environmental predictors of suicide are studied to improve prediction and prevention of suicide. A better understanding of the neurobiology of suicide can help detect at risk populations and help develop better treatment interventions.

Adolescent↗

PubMed2001

Prolactin response to dl-fenfluramine challenge before and after treatment with paroxetine.

The prolactin response to dl-fenfluramine (an indirect central serotonin agonist) challenge has been used to assess serotonergic function and appears to be blunted in depressed patients. We used this method to determine whether the serotonergic deficit in depressed patients is corrected by treatment with paroxetine. Prior to treatment with paroxetine sixteen depressed patients received a placebo challenge followed by a dl-fenfluramine challenge the next day. The same two challenges were repeated after treatment. Prolactin baseline levels were measured before pill administration, and then hourly for 5 hours. Fenfluramine/norfenfluramine levels were assayed at each time point after drug administration. Treatment with paroxetine significantly increased the baseline prolactin level independently of treatment response but positively correlated with paroxetine dose. We found that pre-treatment prolactin response to dl-fenfluramine challenge did not predict clinical response to paroxetine, nor did the prolactin response change significantly after treatment. There was no significant difference in the post-treatment prolactin response between treatment responders and treatment non-responders. We found evidence of increased prolactin levels that may reflect effects of paroxetine in enhancing serotonin levels. Acute release of serotonin as measured by the prolactin response to fenfluramine is not altered by paroxetine treatment.

Aged↗

PubMed2001

Ethnic and sex differences in suicide rates relative to major depression in the United States.

OBJECTIVE: Suicide rates differ between ethnic groups in the United States. Since suicide is commonly associated with a mood disorder, the authors compared suicide rates relative to depression rates in five ethnic groups in the United States. METHOD: Rates of major depression were generated from the Epidemiologic Catchment Area study and the Hispanic Health and Nutrition Epidemiologic Survey. Sociodemographic effects were determined by examining depression rates for respondents who were separated or divorced, earning low incomes, or not working for pay. The survey data were analyzed with age and sex standardization to generate 1-year prevalence rates of major depression. The depression rates of the different ethnic groups were compared and were examined in relation to suicide rates. RESULTS: The 1-year prevalence rates of major depression were 3.6% for whites, 3.5% for blacks, 2.8% for Mexican Americans, 2.5% for Cuban Americans, and 6.9% for Puerto Ricans. Compared to the rate for whites, the rate of depression was significantly higher in Puerto Ricans and significantly lower in Mexican Americans. Relative to the depression rates, the annual suicide rates were higher for males than for females. Mexican American and Puerto Rican males had lower relative suicide rates than white males. CONCLUSIONS: Identifying reasons for differences in suicide rates relative to depression among ethnic groups and between males and females may suggest interventions to reduce suicide rates. Some possibilities are that depression differs in form or severity or that unidentified factors protect against suicide in different subgroups.

Adult↗

PubMed2001

Decreased regional brain metabolism after ect.

OBJECTIVE: The antidepressant action of ECT may be related to its anticonvulsant properties. Positron emission tomography (PET) studies of regional cerebral metabolic rate for glucose were used to test this hypothesis. METHOD: Ten patients with major depression were studied with PET before and approximately 5 days after a course of bilateral ECT. Statistical parametric mapping was used to identify regions of decreased cerebral glucose metabolism. RESULTS: Widespread regions of decreased regional cerebral glucose metabolism were identified after ECT, especially in the frontal and parietal cortex, anterior and posterior cingulate gyrus, and left temporal cortex. A region-of-interest analysis similarly indicated post-ECT reductions in regional cerebral glucose metabolism. CONCLUSIONS: ECT reduces neuronal activity in selected cortical regions, a potential anticonvulsant and antidepressant effect.

Brain↗

PubMed2001

Neuropsychological dysfunction in depressed suicide attempters.

OBJECTIVE: Neuropsychological deficits in the context of psychiatric disease may be associated with suicide risk. In this study, neuropsychological performance was compared among depressed patients with at least one prior suicide attempt of high lethality, depressed patients with low-lethality prior attempts, depressed patients with no prior suicide attempts, and nonpatients. METHOD: Fifty unmedicated patients in a major depressive episode (21 with no history of suicide attempts and 14 and 15 patients with previous attempts of low and high lethality, respectively) and 22 nonpatients were assessed. Groups were comparable in age, education, occupational level, and estimated premorbid intelligence. The neuropsychological battery produced scores within five composite domains: general intellectual functioning (current), motor functioning, attention, memory, and executive functioning. RESULTS: Patients whose prior suicide attempts were of high lethality performed significantly worse than all groups on tests of executive functioning and were the only group to perform significantly worse than nonpatients on tests of general intellectual functioning, attention, and memory. A discriminant function analysis revealed two prominent dimensions in the data: one that discriminated high-lethality suicide attempters from all other groups (primarily associated with performance on tests of executive functioning) and another that discriminated all depressed patient groups from nonpatients (associated with performance on measures of attention and memory). For the patients with high-lethality prior suicide attempts, deficits did not appear to reflect diffuse brain damage from past attempts, since the results of tests commonly affected by diffuse injury were not selectively impaired. CONCLUSIONS: Neuropsychological deficits in depressed patients with high-lethality prior suicide attempts suggest impairment of executive functioning beyond that typically found in major depression. This more extensive neuropsychological impairment in the context of depression may be a risk factor for severe suicide attempts.

Adult↗

PubMed2001

Delusions and suicidality.

OBJECTIVE: Delusions have been considered a risk factor for suicidal behavior. To determine whether specific delusion types are related to suicidal behaviors, the authors compared the clinical characteristics of patients with mood disorders and schizophrenia who did and did not have a history of suicide attempts. METHOD: After admission for inpatient or outpatient psychiatric treatment, 429 patients (ages 14-72 years; 47.1% male; and 73.0% Caucasian) were assessed with a structured clinical interview that generated axis I and II diagnoses. In addition, their psychiatric symptoms, history of suicide attempts, and overall functioning were rated. RESULTS: Data for three diagnostic subgroups (223 patients with major depression, 150 with schizophrenia, and 56 with bipolar disorder) were analyzed separately. Multivariate analyses did not find evidence of a relationship between delusions and history of suicidal ideation or suicide attempts in any of the diagnostic groups. CONCLUSIONS: This study did not find evidence that the presence of delusions distinguished persons with or without a history of suicide attempt.

Adolescent↗

PubMed2001

Identifying and managing suicide risk in bipolar patients.

Bipolar patients have been shown to be at high risk for suicidal behavior. Therefore, identifying potentially suicidal patients is necessary in the treatment of bipolar patients. A stress-diathesis model for suicidal behavior has been proposed to assist clinicians in determining which patients are at risk. In the model, suicidal behavior is the result of the interaction between an individual's threshold for suicidal acts and the stressors that can lead to suicidal behavior. Suicide risk factors can then be categorized as either diathesis-related or stress-related. In a study applying the model of suicidal behavior to bipolar disorder, bipolar patients who attempted suicide had higher levels of suicidal ideation, lifetime aggression, and substance abuse than the comparison group of nonattempters. Attempters had twice the number of major depressive episodes. Once high-risk patients are identified, their suicide risk can be managed through treatments such as prophylactic lithium treatment and other pharmacologic approaches.

Bipolar Disorder↗

PubMed2000

Suicidal behavior in bipolar mood disorder: clinical characteristics of attempters and nonattempters.

OBJECTIVE: Bipolar Disorder is associated with a higher frequency of attempted suicide than most other psychiatric disorders. The reasons are unknown. This study compared bipolar subjects with a history of a suicide attempt to those without such a history, assessing suicidal behavior qualitatively and quantitatively, and examining possible demographic, psychopathologic and familial risk factors. METHODS: Patients (ages 18 to 75) with a DSM III-R Bipolar Disorder (n = 44) diagnosis determined by a structured interview for Axis I disorders were enrolled. Acute psychopathology, hopelessness, protective factors, and traits of aggression and impulsivity were measured. The number, method and degree of medical damage was assessed for suicide attempts, life-time. RESULTS: Bipolar suicide attempters had more life-time episodes of major depression, and twice as many were in a current depressive or mixed episode, compared to bipolar nonattempters. Attempters reported more suicidal ideation immediately prior to admission, and fewer reasons for living even when the most recent suicide attempt preceded the index hospitalization by more than six months. Attempters had more lifetime aggression and were more likely to be male. However, attempters did not differ from nonattempters on lifetime impulsivity. LIMITATIONS: The generalizability of the results is limited because this is a study of inpatients with a history of suicide attempts. Patients with Bipolar I and NOS Disorders were pooled and a larger sample is needed to look at differences. We could not assess psychopathology immediately prior to the suicide attempt because, only half of the suicide attempters had made attempts in the six months prior to admission. Patients with current comorbid substance abuse were excluded. No suicide completers were studied. CONCLUSIONS: Bipolar subjects with a history of suicide attempt experience more episodes of depression, and react to them by having severe suicidal ideation. Their diathesis for acting on feelings of anger or suicidal ideation is suggested by a higher level of lifetime aggression and a pattern of repeated suicide attempts.

Adult↗

PubMed2000

The biology of impulsivity and suicidality.

Abnormalities of 5-HT and noradrenergic functioning have been implicated in aggressive impulsivity, SIB, and suicidal behavior. The role of DA and GABA in human studies of these behaviors requires further investigation. Most studies suggest that impulsive aggression is related to lower levels of CNS 5-HT. Some studies demonstrate that increasing NE correlates to impulsive aggression, whereas other studies demonstrate an opposite relationship. The role of NE in impulsive aggressive behavior is still unclear. Self-injurious behavior is similar to impulsive aggression in that it seems to be mediated by the neurotransmitter systems previously mentioned. For example, the presence of lower levels of 5-HT and abnormalities in the DA system are related to SIB in patients with BPD and depression. SIB severity also seems to be influenced by neglect (e.g., severe isolation during rearing). As animal studies suggest, increasing the amount of isolation and an earlier onset of isolation increase the severity of SIB. Suicidal behaviors and the lethality of suicide attempts may also be linked to the abnormalities in neurotransmitter systems similar to those found in patients with impulsive aggression and SIB, namely, lowered 5-HT transmission and enhanced DA and NE functioning. Understanding the biological triggers of impulsive aggression or SIB may allow for the evaluation of suicidal attempts and completion from a different perspective and, in conjunction with genetic predictors, may eventually help with the early prediction and prevention of suicidal behaviors. Additional studies of live subjects and postmortem brains will assist in clarifying the neurobiology of suicidal behaviors that are common to many disorders and are clinically relevant to BPD.

Aggression↗

PubMed2000

Anxiety in major depression: relationship to suicide attempts.

OBJECTIVE: This study was an examination of the relationship of lifetime panic disorder and anxiety symptoms at index hospitalization to a history of a suicide attempt in patients with a major depressive episode. METHOD: A total of 272 inpatients with at least one major depressive episode, with or without a history of a suicide attempt, were entered into the study. They were given structured diagnostic interviews for axis I and axis II disorders. Suicide attempt history, current psychopathology, and traits of aggression and impulsivity were also assessed. RESULTS: The rates of panic disorder did not differ in the suicide attempters and nonattempters. Agitation, psychic anxiety, and hypochondriasis were more severe in the nonattempter group. A multivariate analysis confirmed that this effect was independent of aggression and impulsivity. CONCLUSIONS: Comorbid panic disorder in patients with major depression does not seem to increase the risk for lifetime suicide attempt. The presence of greater anxiety in the nonattempters warrants further investigation.

Adolescent↗

PubMed2000

Protective factors against suicidal acts in major depression: reasons for living.

OBJECTIVE: Over 30,000 people a year commit suicide in the United States. Prior attempted suicide and hopelessness are the most powerful clinical predictors of future completed suicide. The authors hypothesized that "reasons for living" might protect or restrain patients with major depression from making a suicide attempt. METHOD: Inpatients with DSM-III-R major depression were assessed for depression, general psychopathology, suicide history, reasons for living, and hopelessness. Of the 84 patients, 45 had attempted suicide and 39 had not. RESULTS: The depressed patients who had not attempted suicide expressed more feelings of responsibility toward family, more fear of social disapproval, more moral objections to suicide, greater survival and coping skills, and a greater fear of suicide than the depressed patients who had attempted suicide. Scores for hopelessness, subjective depression, and suicidal ideation were significantly higher for the suicide attempters. Reasons for living correlated inversely with the combined score on these measures, considered an indicator of "clinical suicidality." Neither objective severity of depression nor quantity of recent life events differed between the two groups. CONCLUSIONS: During a depressive episode, the subjective perception of stressful life events may be more germane to suicidal expression than the objective quantity of such events. A more optimistic perceptual set, despite equivalent objective severity of depression, may modify hopelessness and may protect against suicidal behavior during periods of risk, such as major depression. Assessment of reasons for living should be included in the evaluation of suicidal patients.

Adaptation, Psychological↗

PubMed1999

Inadequacy of antidepressant treatment for patients with major depression who are at risk for suicidal behavior.

OBJECTIVE: The authors' goal was to determine whether suicide attempters with major depression received more intensive antidepressant treatment than depressed patients who had not attempted suicide. METHOD: One hundred eighty inpatients who met DSM-III-R criteria for a major depressive episode according to the Structured Clinical Interview for DSM-III-R were enrolled in the study. All patients were assessed for lifetime history of suicide attempts. Depressive symptoms at the index hospitalization were assessed with the Hamilton Depression Rating Scale and the Beck Depression Inventory. Strength of antidepressant treatment over the 90 days preceding the hospitalization was scored by using the Antidepressant Treatment History Form. RESULTS: A large majority of the depressed patients with a history of suicide attempts, who were at higher risk for future suicide and suicide attempts, received inadequate treatment. Similarly, most of the depressed patients at lower risk for suicide attempts also received inadequate treatment. CONCLUSIONS: Major depression is undertreated pharmacologically, regardless of history of suicide attempt. Some suicide attempts may be preventable if the problem of underdiagnosis and undertreatment of depression can be overcome by psychoeducation for health professionals and the public.

Adult↗