Harry Brittain

Alzheimer's disease is rare in Cree

A community survey and subsequent clinical assessment of 192 Cree aged 65 years and over registered in two Reserves in Northern Manitoba identified only one case of probable Alzheimers disease among eight cases of dementia, giving a prevalence of 0.5% for Alzheimers disease and 4.2% for all dementias. This contrasted with an age-adjusted prevalence of 3.5% for Alzheimers disease and 4.2% for all dementias in an age-stratified sample of 241 English-speaking residents of Winnipeg. Although it was not so for all dementias, the difference between the groups for prevalence of Alzheimers disease was highly significant (p < .001). The age-specific patterns of all dementias in the two groups were significantly different, however (p = .0254).

A study of anxiety/depressive symptoms of medical students, house staff, and their spouses/partners

Symptoms of anxiety/depression and suicidal ideation were studied in medical students, house staff, and their spouses/partners in a large midwestern school by means of an anonymous questionnaire. A total of 634 medical students and 227 house staff completed the questionnaire. A significantly higher proportion of female trainees than male trainees reported symptoms of anxiety/depression (41% compared with 27%). This difference between men and women was most marked during residency training. The proportion of men reporting anxiety/ depressive symptoms declined between medical school (33%) and residency (10%). No such decline occurred with women (medical students 42%, residents 37%).

The CAMDEX: A Standardized Instrument for the Diagnosis of Mental Disorder in the Elderly: A Replication with a US Sample

The Cambridge Mental Disorders of the Elderly Examination (CAMDEX) was developed by Roth, et al (1986) to assist in the early diagnosis and measurement of dementia in the elderly. In this study the CAMDEX was administered to a mixed group of independently diagnosed elderly psychiatric patients and control subjects in the United States. The CAMDEX was found to have a high interrater reliability with a mixed group of clinicians of varying backgrounds. The diagnostic scales and the cognitive section of the CAMDEX demonstrated considerable promise in distinguishing between independently diagnosed populations of depressed, demented, and normal subjects. The results suggest comparability between samples of subjects in England and the US, and that the CAMDEX is a promising instrument for use in both research and clinical settings.

Blunted ACTH and Cortisol Response to Afternoon Tryptophan Infusion in Euthymic Bipolar Patients

The serotonin precursor tryptophan was used to test neuroendocrine responses in remitted bipolar patients and controls. Tryptophan was administered in the afternoon when spontaneous cortisol secretion is lower than in the morning. Following pilot studies at various doses, 50 mg/kg L-tryptophan was given i.v. over 20 min to 11 patients and 14 controls. Controls demonstrated cortisol release, whereas the response curve for patients was indistinguishable from placebo. Differences between groups were significant at 15, 30, and 45 min. Changes in adrenocorticotropic hormone were consistent with those in cortisol. Prolactin and growth hormone levels increased in both patients and controls following tryptophan. Higher doses caused gastrointestinal upset in some subjects.

Biological stress responses in high and low trait anxious students

In an investigation of biological indicators of stress in normal humans, undergraduate psychology students were differentiated on trait anxiety and assessed under baseline, preexam (stress), and postexam conditions. Assessment at each condition involved drawing 20 ml of blood, followed by self-reporting for selected questionnaires. Self-reports included state anxiety, general psychological symptomatology, dysfunctional attitudes, academic confidence, sleep patterns, and intake of drugs, including alcohol and caffeine. Blood was analyzed for whole blood serotonin content, plasma MHPG, and platelet imipramine binding. Baseline differences between high and low trait anxious students on biological measures were significant only for whole blood serotonin content. Variation across situational conditions was significant for whole blood serotonin, with an increase under the stressful condition for both anxiety groups. Thus, serotonin is highlighted as an important factor in the human response to stress, whereas expected differences in MHPG were not observed. The serotonergic response to stress was not explained by changes in psychological or physical state variables. Changes in serotonin content were positively correlated with changes in platelet imipramine binding.

IQ Deficit in Schizophrenia: A Test of Competing Theories.

This study tested competing interpretations of IQ deficit in schizophrenic patients. One interpretation (concomitancy hypothesis) holds that IQ loss is a product of schizophrenic symptoms and is remedied as the symptoms remit. The second (prodromal hypothesis) holds that IQ deficit preceeds and facilitates the development of schizophrenic disorder and is not remedied with symptom remission. The IQs of schizophrenic patients were obtained before and three times after hospital treatment. All mean IQs fell within average limits and did not increase significantly after treatment although test-retest correlations suggested slight disruption of IQ in the morbid state. Remitting cases did not differ significantly from nonremitting cases. Paradoxically, chronic patients earned slightly higher IQs than acute patients. The findings are interpreted as providing some support for both interpretations of schizophrenic IQ deficit. It is concluded that the specific IQ tests used and the nature of the patient samples tested will have a significant bearing on which hypothesis is supported in individual studies of schizophrenic IQ deficit.

Erythrocyte membrane structure in bipolar affective disorder: a non-replication.

Fifteen bipolar patients were compared with sixteen controls in an attempt to replicate the findings of Pettegrew et al. in 1982 of decreased fluidity in the hydrocarbon core of the erythrocyte membrane. No significant differences were seen between groups. The present control group shows very similar membrane characteristics to the original control series; however, the bipolar patient group is not similar. Possible explanations are discussed.

Serotonin, Imipramine Binding, Cortisol and Anxiety in Humans Under Stress

Although noradrenergic and serotonergic neurotransmitter systems have been implicated in stress among animals and humans [1,4] specific biological indicators of human stress have produced inconsistent results [3].