Biomedical subjects

Christopher Cox

Publications and source records attributed to Christopher Cox.

61 records · Page 4Linked to original sources

PubMedDate not supplied

Impaired cued delayed alternation behavior in adult rat offspring following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin on gestation day 15.

This investigation used random ratio (RR) and cued delayed alternation procedures to examine the operant behavior of adult male and female rats following prenatal 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Offspring were exposed to a single maternal dose of 0.0, 0.06, 0.18 or 0.54 microg/kg po of TCDD on gestation day (GD) 15. For RR, adult subjects were trained to respond on one lever in a two-lever chamber for food reinforcement. The response requirement was increased across sessions. Male offspring responded at higher rates than females regardless of RR value and prenatal exposure history. For delayed alternation, animals were required to alternate responses on both apparatus levers and to inhibit responding during randomly interpolated delay intervals. The performance of male and female offspring exposed to 0.18-microg/kg TCDD was significantly less accurate and this group committed more errors by responding during the delay intervals than the other exposure groups. A similar trend was observed in the 0.54- microg/kg group. Overall, response accuracy during the delayed alternation procedure was inversely related to delay length and tended to improve with experience. Interpretations of these outcomes include the possibility that TCDD interfered with the development of attentional processes, impaired response inhibition or promoted response perseveration despite the presence of cues, indicating changes in reinforcement contingencies.

Administration, Oral↗

PubMedDate not supplied

Preliminary report on childhood sexual abuse, suicidal ideation, and suicide attempts among middle-aged and older depressed women.

OBJECTIVE: Authors examined the relationship between childhood sexual abuse histories and suicidal ideation and behavior among depressed women age 50 years and older. METHODS: After admission to a psychiatric unit, participants were administered the Structured Clinical Interview for DSM-III-R and measures of suicidal ideation and behavior. RESULTS: Women who reported abuse histories were more likely to report suicidal ideation at the time of hospitalization and a history of multiple suicide attempts. CONCLUSIONS: These preliminary findings underscore the need for more study of how childhood abuse amplifies risk for suicidal ideation and behavior among women across the life course.

Child↗

PubMedDate not supplied

Dementia consults: predictors of compliance by primary care physicians.

This study was designed to determine rates of primary care physician compliance with recommendations made by physician-consultants at an Alzheimer's disease center. A mail survey was sent to primary care physicians, who were asked to indicate which recommendations had been implemented and to select reasons for lack of adherence. The response rate was 53 percent (49/92). Some 83 percent of recommendations were implemented. Compliance with medical recommendations was higher (87 percent) than with social or behavioral issues (69 percent). Reasons for noncompliance indicated that patient or family barriers were responsible in 48 percent of cases, while physicians were responsible in 24 percent. These findings validate the development of two educational programs: curricula that support the primary care physician in conveying the value of these interventions and guidelines to assist specialists in communicating treatment recommendations.

Aged↗

PubMedDate not supplied

Depressive disorders and symptoms in older primary care patients: one-year outcomes.

Syndromically diagnosable and subsyndromal depressions have substantial prevalence and functional morbidity among older persons seen in primary care, but their naturalistic outcome is largely unknown. The authors describe depressive symptoms and syndromes and functional outcomes at 1-year follow-up and examine specific outcome predictors in a cohort study using psychopathological, medical, and functional assessments at intake and 1-year follow-up. Subjects were 247 patients over age 60, recruited from private internal medicine offices and a university-affiliated family medicine clinic. Multiple-regression techniques examined the independent association of intake variables to outcome measures. Of the 63 subjects with an active depression diagnosis at study intake, 36 (57%) still had an active depression diagnosis at 1 year. The outcome for major depression was worse than for minor or subsyndromal depression. Medical illness burden and neuroticism were independent predictors of outcome. Major depression and depressive symptom severity were independently associated with poorer social functioning at follow-up. Depressive conditions had considerable rates of persistence, yet the outcome was not uniformly poor. Longer-term naturalistic study is needed, as are treatment studies targeting those at highest risk of recurrence or chronicity.

Aged↗

PubMedDate not supplied

Access to firearms and risk for suicide in middle-aged and older adults.

Elderly white men are at the highest risk for suicide. Firearms are the most common method of suicide used by both men and women in later life, and a greater proportion of older than younger suicide victims use a gun. This psychological autopsy study aimed to test hypotheses concerning the risk for suicide associated with access to and storage of firearms. Subjects included 86 suicide victims age 50 years of age and over and 86 community control subjects individually matched on age, sex, race, and county of residence. Presence of a firearm in the home was associated with increased risk for suicide, even after controlling for psychiatric illness. Elevated risk was accounted for by access to handguns rather than long guns and was more pronounced in men than women. Among subjects who kept a gun in the home, storing the weapon loaded and unlocked were independent predictors of suicide. Findings support the potential benefit for suicide prevention of restricting access to handguns. Education programs for older persons, their families, and healthcare providers concerning the risks of having a gun in the home and reinforcement of rules for safe storage may contribute to reducing the rate of suicide in older people.

Age Factors↗

PubMedDate not supplied

Valproate therapy for agitation in dementia: open-label extension of a double-blind trial.

OBJECTIVE: The authors describe an open-label extension of a double-blind, randomized, placebo-controlled study of divalproex sodium in 56 nursing home patients with agitation and dementia. METHODS: Participants (N=46) were treated for 6 weeks in an open fashion with clinically optimal doses of divalproex sodium (range: 250 mg/day-1,500 mg/day; mean: 851 mg/day). Behavior was assessed with the Brief Psychiatric Rating Scale (BPRS) and Clinical Global Impression of Change (CGI) by new raters. Safety, tolerability, and laboratory data were obtained regularly. RESULTS: The mean BPRS Agitation Factor decreased by 3.1 points from baseline; 86% of those completing the open phase were rated as improved on the CGI. These changes were mirrored by changes in other behavior rating scales. Sixty percent of subjects had no side effects; 33% had side effects that were rated as mild. There were no clinically significant changes in laboratory values. CONCLUSION: Ongoing open-label treatment with divalproex was associated with improvement in measures of agitation. Doses, levels, and tolerability were similar to those in the blinded phase of the study. These findings help confirm and extend the results from the placebo-controlled phase of the trial and suggest that divalproex may be beneficial for some patients with this clinical problem.

Aged↗

PubMedDate not supplied

Social support, depression, and functional disability in older adult primary-care patients.

OBJECTIVE: The authors asked whether social support and depression are independently associated with functional disability and examined the potential role of social support as a moderator in the depression-functional disability association. METHODS: Subjects were 305 patients age 60 years and over. Predictor variables were social support, depressive symptoms, and depression diagnosis. Dependent variables were the Instrumental Activities of Daily Living Scale, the Physical Self-Maintenance Scale, and the Physical Functioning subscale of the Medical Outcomes Study 36-Item Short-Form Health Survey. Authors used multiple-regression analyses. RESULTS: Depressive symptoms and all dimensions of social support were independently associated with functional disability: the specifics of these relationships varied among types of social support and functional disability. Depression diagnosis was not independently associated with any functional disability measure. Social support (more instrumental help, more perceived satisfaction) moderated some depression diagnosis-functional disability associations, and one depressive symptom-functional disability association. CONCLUSIONS: The study hypotheses were partially confirmed. Different dimensions of social support have important and varied roles in the depression-functional disability dynamic. Future research is needed to further specify the complex relationships among depression, social support, and functional disability.

Activities of Daily Living↗