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Biomedical subjects

A C Leon

Publications and source records attributed to A C Leon.

At least 37 records · Page 2Linked to original sources
PubMed2000

Multiple recurrences of major depressive disorder.

OBJECTIVE: The authors of this study examined multiple recurrences of unipolar major depressive disorder. METHOD: A total of 318 subjects with unipolar major depressive disorder were prospectively followed for 10 years within a multicenter naturalistic study. Survival analytic techniques were used to examine the probability of recurrence after recovery from the index episode. RESULTS: The mean number of episodes of major depression per year of follow-up was 0. 21, and nearly two-thirds of the subjects suffered at least one recurrence. The number of lifetime episodes of major depression was significantly associated with the probability of recurrence, such that the risk of recurrence increased by 16% with each successive recurrence. The risk of recurrence progressively decreased as the duration of recovery increased. Within subjects, there was very little consistency in the time to recurrence. CONCLUSIONS: Major depressive disorder is a highly recurrent illness. The risk of the recurrence of major depressive disorder progressively increases with each successive episode and decreases as the duration of recovery increases.

Adolescent↗
PubMed2000

Does incomplete recovery from first lifetime major depressive episode herald a chronic course of illness?

OBJECTIVE: This study investigated the influence of incomplete recovery from first lifetime major depressive episodes on long-term outcome. METHOD: After their first lifetime major depressive episode, patients were divided into asymptomatic (N=70) and residual subthreshold depressive symptom (N=26) recovery groups and compared on longitudinal course during up to 12 years of prospective naturalistic follow-up. RESULTS: Patients with residual subthreshold depressive symptoms during recovery had significantly more severe and chronic future courses. Those with residual symptoms relapsed to major and minor depressive episodes faster and had more recurrences, shorter well intervals, and fewer symptom-free weeks during follow-up than asymptomatic patients. CONCLUSIONS: Resolution of major depressive episodes with residual subthreshold depressive symptoms, even the first lifetime episode, appears to be the first step of a more severe, relapsing, and chronic future course. When ongoing subthreshold symptoms continue after major depressive episodes, the illness is still active, and continued treatment is strongly recommended.

Antidepressive Agents↗
PubMed2000

Rater agreement on interpersonal psychotherapy problem areas.

There has been much outcome research on interpersonal psychotherapy (IPT) but little investigation of its components. This study assessed interrater reliability of IPT therapists in identifying interpersonal problem areas and treatment foci from audiotapes of initial treatment sessions. Three IPT research psychotherapists assessed up to 18 audiotapes of dysthymic patients, using the Interpersonal Problem Area Rating Scale. Cohen's kappa was used to examine concordance between raters. Kappas for presence or absence of each of the four IPT problem areas were 0.87 (grief), 0.58 (role dispute), 1.0 (role transition), and 0.48 (interpersonal deficits). Kappa for agreement on a clinical focus was 0.82. IPT therapists agreed closely in rating problem areas and potential treatment foci, providing empirical support for potential therapist consistency in this treatment approach.

Adult↗
PubMed1999

Linguistic threat activates the human amygdala.

Studies in animals demonstrate a crucial role for the amygdala in emotional and social behavior, especially as related to fear and aggression. Whereas lesion and functional-imaging studies in humans indicate the amygdala's participation in assessing the significance of nonverbal as well as paralinguistic cues, direct evidence for its role in the emotional processing of linguistic cues is lacking. In this study, we use a modified Stroop task along with a high-sensitivity neuroimaging technique to target the neural substrate engaged specifically when processing linguistic threat. Healthy volunteer subjects were instructed to name the color of words of either threat or neutral valence, presented in different color fonts, while neural activity was measured by using H(2)(15)O positron-emission tomography. Bilateral amygdalar activation was significantly greater during color naming of threat words than during color naming of neutral words. Associated activations were also noted in sensory-evaluative and motor-planning areas of the brain. Thus, our results demonstrate the amygdala's role in the processing of danger elicited by language. In addition, the results reinforce the amygdala's role in the modulation of the perception of, and response to, emotionally salient stimuli. The current study further suggests conservation of phylogenetically older mechanisms of emotional evaluation in the context of more recently evolved linguistic function.

Adult↗
PubMed1999

Correlates of suicidal ideation in dysphoric mania.

BACKGROUND: Previous investigations have reported that suicidal ideation and behavior are more prevalent during mixed than pure mania. Uncertainties exist about whether suicidality in mania arises from multiple concurrent depressive symptoms, or rather, as a categorical phenomenon, reflecting dysphoria without necessarily a full major depression. To elucidate the relationship between suicidal ideation and dysphoric mania, we analyzed clinical and demographic features associated with suicidal versus nonsuicidal dysphoric manic inpatients. METHODS: Records were reviewed for 100 DSM-III-R bipolar I manic inpatients at the Payne Whitney Clinic of New York Hospital from 1991-1995. All had > or = 2 concomitant depressive symptoms (other than suicidality). Affective and psychotic symptoms, past suicide attempts, prior illness, and related clinical/demographic variables were assessed by a standardized protocol. RESULTS: Suicidal ideation was significantly more common among dysphoric manics who were caucasian, took antidepressant medications in the week prior to admission, had histories of alcohol abuse/dependence, and made past suicide attempts. Suicidal ideation was evident for nearly half of dysphoric manic patients with < or = 3 depressive symptoms who did not meet DSM criteria for a mixed state. No individual manic or depressive symptoms other than dysphoric mood were more common among suicidal than nonsuicidal patients. LIMITATIONS: Findings from this retrospective study require confirmation using a prospective assessment. Treatments were naturalistic and may have differentially influenced hospital course and illness characteristics. Factors related to suicide attempts (rare in this cohort) or completions (not a focus of this study) may differ from those related only to suicidal ideation. CONCLUSIONS: Caucasian dysphoric manic patients with past suicide attempts and substance abuse may have a significantly elevated risk for suicidality, even when full major depression does not accompany mania. Suicidality is a clinically important consideration in a majority of dysphoric manic patients.

Adult↗
PubMed1999

The Range of Impaired Functioning Tool (LIFE-RIFT): a brief measure of functional impairment.

BACKGROUND: The literature documents that functional impairment is associated with affective disorders. Nevertheless, the choice among thorough, yet brief, well-validated assessments of functional impairment is limited. The objective of this study was to evaluate the psychometric properties of a brief scale of functional impairment, the Range of Impaired Functioning Tool (LIFE-RIFT). METHOD: The study sample included subjects who presented with major depressive disorder at intake into the NIMH Collaborative Depression Study (CDS). The LIFE-RIFT is composed of items that are included in the Longitudinal Interval Follow-up Evaluation (LIFE). The reliability and validity were examined using data from LIFE-RIFT assessments conducted at four points in time: 6, 12, 18 and 24 months after intake into the CDS. RESULTS: Cross-sectional one factor models accounted for the covariance structure among the four scale items. A longitudinal factor model, with an invariant factor structure over time, also fitted the data well and indicated that the scale items are measures of one construct, namely functional impairment. The internal consistency reliability of the scale was supported with alpha coefficients ranging from 0.81 to 0.83. The inter-rater reliability intraclass correlation coefficient (ICC) was 0.94. Mixed-effect linear regression models showed that those in episode were significantly more impaired than those in recovery. Furthermore, in analyses of predictive validity, impairment was positively associated with subsequent recurrence and negatively associated with subsequent recovery. CONCLUSIONS: This psychometric evaluation provides empirical support for the reliability and validity of the LIFE-RIFT, a brief measure of functional impairment.

Activities of Daily Living↗
PubMed1999

Predictors of management problems in supported housing: a pilot study.

The study examined predictors of management problems among residents of a supported single room occupancy hotel (SRO) for persons with severe and persistent mental illness (SPMI). Case workers completed questionnaires on the prior six months. We found that medication-compliant residents without drug abuse were rarely disruptive, while those with co-morbid substance abuse were often disruptive. Residents non-compliant with medication also tended to cause management problems whether or not they abused drugs. Supported residences should be staffed and organized to minimize medication non-compliance and substance abuse which are associated with behavioral disruptiveness.

Adult↗
PubMed1999

Polarity sequence, depression, and chronicity in bipolar I disorder.

Five independent studies show that polarity sequence is associated with prognosis in bipolar I disorder. Episodes in which major depression precedes mania (DMI) lead to higher morbidity than biphasic episodes which begin with mania (MDI). However, little is known about the prognostic significance of polarity sequence for long-term outcome. This study examined polarity sequence across multiple episodes among 165 bipolar I patients followed prospectively for up to 15 years as part of the NIMH Collaborative Study of Depression. Episodes beginning with major depression were significantly longer than those beginning with mania for the first three prospectively observed episodes when pooling all episode types-monophasic, biphasic, and polyphasic. Furthermore, affective polarity at onset for the first prospectively observed episode was associated with polarity at onset for the remaining three episodes. Patients whose first prospectively observed episode began with depression had higher overall morbidity during the entire follow-up period.

Adult↗
PubMed1999

Long-term prognosis of bipolar I disorder.

This study examined the contribution of demographic, syndromal and longitudinal course variables to the long-term prognosis of 165 bipolar patients prospectively observed over 10 years as part of the National Institute of Mental Health Collaborative Study of Depression. Although most baseline clinical and demographic variables were not strong prognostic indicators, switching polarity within episodes was. Most episodes among the poor-prognosis patients were polyphasic, while most episodes among the comparison group with a better prognosis were monophasic. There was no evidence of shortening of cycle lengths over follow-up for either the poor-prognosis group or the entire sample. The relevance of these findings to the 'kindling' model is discussed.

Adult↗
PubMed1999

Prospective study of fluoxetine treatment and suicidal behavior in affectively ill subjects.

OBJECTIVE: There has been speculation in the literature about a link between fluoxetine use and suicidal behavior. The authors of this study hypothesized that there is no elevation in risk of suicidal behavior associated with use of fluoxetine. METHOD: The data come from the National Institute of Mental Health Collaborative Depression Study, a prospective, naturalistic follow-up of persons who presented for treatment of affective disorders. The analyses included data on 643 subjects who were followed up after fluoxetine was approved by the Food and Drug Administration in December 1987 for the treatment of depression. RESULTS: Nearly 30% (N = 185) of the study group was treated with fluoxetine at some point during the follow-up period. Relative to the other subjects, those who were subsequently treated with fluoxetine had onset of affective illness at a younger age and, after intake into the study and before 1988, had elevated rates of suicide attempts before fluoxetine treatment. A mixed-effects survival analysis that incorporated treatment exposure time, multiple treatment trials, and multiple suicide attempts per subject showed that relative to no treatment, use of fluoxetine and use of other somatic antidepressants were associated with nonsignificant reductions in the likelihood of suicide attempts or completions. Severity of psychopathology was strongly associated with elevated risk, and each suicide attempt after intake into the Collaborative Depression Study was associated with a marginally significant increase in risk of suicidal behavior. CONCLUSIONS: The results do not support the speculation that fluoxetine increases the risk of suicide. Rather, there was a nonsignificant reduction in risk of suicidal behavior among patients treated with fluoxetine, even though those subjects were more severely ill before treatment with fluoxetine.

Adult↗
PubMed1999

Recurrence after recovery from major depressive disorder during 15 years of observational follow-up.

OBJECTIVE: The recurrence of an affective disorder in people who initially recover from major depressive disorder was characterized by using the unique longitudinal prospective follow-up data from the National Institute of Mental Health Collaborative Program on the Psychobiology of Depression-Clinical Studies. METHOD: Up to 15 years of prospective follow-up data on the course of major depressive disorder were available for 380 subjects who recovered from an index episode of major depressive disorder and for 105 subjects who subsequently remained well for at least 5 years after recovery. Baseline demographic and clinical characteristics were examined as predictors of recurrence of an affective disorder. The authors also examined naturalistically applied antidepressant therapy. RESULTS: A cumulative proportion of 85% (Kaplan-Meier estimate) of the 380 recovered subjects experienced a recurrence, as did 58% (Kaplan-Meier estimate) of those who remained well for at least 5 years. Female sex, a longer depressive episode before intake, more prior episodes, and never marrying were significant predictors of a recurrence. None of these or any other characteristic persisted as a predictor of recurrence in subjects who recovered and were subsequently well for at least 5 years. Subjects reported receiving low levels of antidepressant treatment during the index episode, which further decreased in amount and extent during the well interval. CONCLUSIONS: Few baseline demographic or clinical characteristics predict who will or will not experience a recurrence of an affective disorder after recovery from an index episode of major depressive disorder, even in persons with lengthy well intervals. Naturalistically applied levels of antidepressant treatment are well below those shown effective in maintenance pharmacotherapy studies.

Adult↗
PubMed1999

Diagnostic errors of primary care screens for depression and panic disorder.

OBJECTIVE: As the health care reimbursement system has changed, brief screens for detecting mental disorders in primary care have been developed. These efforts have faced the formidable task of identifying patients with mental disorders, while at the same time minimizing the number of misclassified cases. Here we consider the balance between sensitivity and positive predictive value. Primary care patients with false positive and false negative results on screens for depression and panic disorder are compared with regard to comorbidity and functional impairment. METHODS: This was a cross-sectional psychometric study. The study sample included 1001 primary care patients from the Department of Internal Medicine at Kaiser Permanente in Oakland, California. The Symptom-Driven Diagnostic System for Primary Care (SDDS-PC) screens and Sheehan Disability Scale were completed by the subjects. The SDDS-PC diagnostic interviews were administered to all subjects. RESULTS: Patients with false positive results on the panic disorder screen did not differ from patients with false negatives results with regard to rates of other psychiatric disorders, functional impairment, or mental health service utilization. In contrast, patients with false negative depression screen results had significantly more psychiatric disorders and functional impairment than those with false positive depression results. CONCLUSIONS: A substantial number of patients with either false positive or false negative screen results met diagnostic criteria for other mental disorders. Given the nominal burden of follow-up assessments for patients with positive screens, these data suggest that erring on the side of sensitivity may have been preferable when algorithms for these screens were selected.

Adolescent↗
PubMed1999

A history of substance abuse complicates remission from acute mania in bipolar disorder.

BACKGROUND: Substance abuse frequently complicates the course of bipolar illness, promotes mixed states, and contributes to poor outcome in mania. Preliminary open trials suggest that anticonvulsant mood stabilizers may enhance remission rates and outcome for bipolar patients with substance abuse. This study compared remission patterns for mixed or pure manic episodes among bipolar inpatients with or without substance abuse histories. METHOD: Hospital records were retrospectively reviewed for 204 DSM-III-R bipolar I inpatients. Clinical features were compared for those with or without substance abuse/dependence histories predating the index manic episode. Time until remission was analyzed by Kaplan-Meier survival analysis. Naturalistic treatment outcome with lithium or anticonvulsant mood stabilizers was compared for those with or without past substance abuse. RESULTS: Past substance abuse was evident in 34% of the bipolar sample and comprised most often alcoholism (82%), followed by cocaine (30%), marijuana (29%), sedative-hypnotic or amphetamine (21%), and opiate (13%) abuse. Substance abuse was more common among men (p < .05) and those with mixed rather than pure mania (p < .05). Remission during hospitalization was less likely among patients with prior substance abuse (p < .05), especially alcohol or marijuana abuse, and among mixed manic patients with past substance abuse (p < .05). Bipolar patients with substance abuse histories who received divalproex or carbamazepine remitted during hospitalization more often than did those who received lithium as the sole mood stabilizer (p < .05). CONCLUSION: These findings support previous reports suggesting that bipolar patients with past substance abuse have poorer naturalistic treatment outcomes, but may show a better response to anticonvulsant mood stabilizers than lithium.

Acute Disease↗
PubMed1998

Ambient temperature and mortality from unintentional cocaine overdose.

CONTEXT: Hot weather taxes cardiovascular function and is associated with increased deaths from heart disease. Cocaine can cause hypertension, tachycardia, coronary vasospasm, arrhythmias, and increased core temperature. OBJECTIVE: To determine the association between mortality from cocaine overdose and hot weather. SETTING: New York, NY. DESIGN: Retrospective review of medical examiner cases from 1990 through 1995. SUBJECTS: All fatal unintentional cocaine overdoses from 1990 through 1992 (n = 1382) and all hyperthermia deaths of cocaine users (n = 10) were used to identify a maximum daily temperature threshold above which mortality from cocaine intoxication increased. The study population consisted of all fatal unintentional cocaine overdoses from 1993 through 1995 (n = 2008) and 4 contemporaneous comparison groups that included fatal unintentional opiate overdoses (n = 793), all other fatal unintentional overdoses (n = 85), and a subset of homicides (n = 4638) and fatalities from motor vehicle crashes (n = 815). MAIN OUTCOME MEASURES: The number of overdose deaths and the proportion of homicides and traffic fatalities with a positive cocaine toxicology test result on days with a maximum temperature above or below the temperature threshold. RESULTS: A threshold temperature of 31.1 degrees C (88 degrees F) was identified, above which the mean daily number of fatal cocaine overdoses increased steadily. On days with a maximum daily temperature of 31.1 degrees C (88 degrees F) or higher ("hot days"), the mean daily number of cocaine overdose deaths was 2.34 (SD = 1.68), which was 33% higher than the mean on days with a maximum temperature of less than 31.1 degrees C (88 degrees F) (mean = 1.76 [SD=1.37] (P<.001). In contrast, the mean number of opiate overdose deaths per day was 0.81 (SD = 0.94) on hot days and 0.71 (SD = 0.86) on other days (P=.28). For other drug overdose deaths, the mean number of deaths per day was 0.08 (SD = 0.28) on hot days and 0.08 (SD = 0.28) on other days (P=.69). Among homicides, the proportion with a positive cocaine toxicology test result was 18.9% on hot days and 19.5% on other days (P=.69), and among traffic fatalities, the proportions with positive cocaine toxicology test results were 9.5% on hot days and 10.3% on other days (P=.91). CONCLUSIONS: High ambient temperature is associated with a significant increase in mortality from cocaine overdose. Based on our comparison groups, the increase is not explained by changes in cocaine use among the general population. Although cocaine use is dangerous on all days, it appears to be even more dangerous on hot days.

Accidents, Traffic↗
PubMed1998

A prospective 12-year study of subsyndromal and syndromal depressive symptoms in unipolar major depressive disorders.

BACKGROUND: Investigations of unipolar major depressive disorder (MDD) have focused primarily on major depressive episode remission/recovery and relapse/recurrence. This is the first prospective, naturalistic, long-term study of the weekly symptomatic course of MDD. METHODS: The weekly depressive symptoms of 431 patients with MDD seeking treatment at 5 academic centers were divided into 4 levels of severity: (1) depressive symptoms at the threshold for MDD; (2) depressive symptoms at the threshold for minor depressive or dysthymic disorder (MinD); (3) subsyndromal or subthreshold depressive symptoms (SSDs), below the thresholds for MinD and MDD; and (4) no depressive symptoms. The percentage of weeks at each level, number of changes in symptom level, and medication status were analyzed overall and for 3 subgroups defined by mood disorder history. RESULTS: Patients were symptomatically ill in 59% of weeks. Symptom levels changed frequently (1.8/y), and 9 of 10 patients spent weeks at 3 or 4 different levels during follow-up. The MinD (27%) and SSD (17%) symptom levels were more common than the MDD (15%) symptom level. Patients with double depression and recurrent depression had more chronic symptoms than patients with their first lifetime major depressive episode (72% and 65%, respectively, vs 46% of follow-up weeks). CONCLUSION: The long-term weekly course of unipolar MDD is dominated by prolonged symptomatic chronicity. Combined MinD and SSD level symptoms were about 3 times more common (43%) than MDD level symptoms (15%). The symptomatic course is dynamic and changeable, and MDD, MinD, and SSD symptom levels commonly alternate over time in the same patients as a symptomatic continuum of illness activity of a single clinical disease.

Adult↗
PubMed1998

A diagnostic aid for detecting (DSM-IV) mental disorders in primary care.

This study was designed to develop and validate a new computerized version of the Symptom Driven Diagnostic System for Primary Care (SDDS-PC) and examine its feasibility in primary care practice. One thousand and one patients (ages 18-70) coming for routine care to Kaiser-Permanente were screened on a self-administered symptom scale for major depression, alcohol and drug dependence, generalized anxiety, panic and obsessive compulsive disorders, and suicidal behavior. The screen was followed up by a brief diagnostic interview, administered by a nurse, which yielded a one-page summary of positive symptoms and a provisional computer-generated diagnosis for the physician. The physician reviewed the summary results and made a diagnosis. The nurse and physician were blind to the screen results. Patients were reinterviewed within 96 hours by a mental health professional (MHP) blind to previous results. The nurses' interviews ranged between 1.5 and 3.5 minutes for a screened positive diagnosis. Agreement between the nurse and physician diagnoses was excellent to moderate. Disagreement was usually in the direction of the physician ruling out major mental disorders in favor of subsyndromal or medical explanations. Only rarely did physicians diagnose disorders not detected by the nurse interview. Agreement between physician and MHP was moderate. Physicians using the SDDS-PC seldom made diagnoses that were not confirmed by the independent assessment of the MHP. The SDDS-PC may facilitate recognition of psychiatric disorders and minimize the physician's time in information gathering.

Adolescent↗
PubMed1998

Bipolar I affective disorder: predictors of outcome after 15 years.

BACKGROUND: Robust predictors of long-term outcome in bipolar affective disorder would have substantial importance to both clinicians and researchers. Such predictors are not available, however, perhaps because of the limitations of previous efforts to find them. METHODS: In this study, 113 patients with bipolar affective disorder were followed semiannually for 5 years and annually for a subsequent 15 years. Of these, 23 (20.4%) had a poor long-term outcome indicated by the presence of mania or major depressive disorder throughout the 15th year. RESULTS: Among the baseline demographic and clinical variables tested, only active alcoholism and low levels of optimum functioning in the preceding 5 years characterized poor outcome patients. The persistence of depressive symptoms in the first 2 years of follow-up predicted depressive symptoms 15 years later but the early persistence of manic symptoms seemed to have no predictive value. A regression analysis eliminated alcoholism as an independent predictor. Thus, only poor optimal functioning in the 5 years before baseline assessment, and the persistence of depressive symptoms in the two subsequent years, were independently associated with poor, long-term prognosis. LIMITATIONS: Patients were recruited at tertiary care centers and sampling was therefore biased toward greater severity and chronicity. As is true of all naturalistic studies of course, treatment was not controlled. CONCLUSION: These findings suggest the existence of a poor outcome, depression-prone subtype of bipolar affective disorder.

Adult↗