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K MacPherson

Publications and source records attributed to K MacPherson.

8 recordsLinked to original sources
PubMed2006

Characterization of mass-labeled [13C14]-decabromodiphenylethane and its use as a surrogate standard in the analysis of sewage sludge samples.

Very little data is available about the presence of the brominated flame retardant, DBDPE, in the environment. This study reports the characterization of [(13)C(14)]-decabromodiphenylethane and the use of this surrogate standard to positively identify and quantify the presence of DBDPE in sewage sludge samples. The large difference in response factors between BDE-209 and DBDPE predicates the use of [(13)C(14)]-decabromodiphenylethane as a surrogate standard to improve the accuracy when determining the levels of DBDPE in environmental samples.

Bromobenzenes↗
PubMed2001

Physical activity and risk of cognitive impairment and dementia in elderly persons.

CONTEXT: Dementia is common, costly, and highly age related. Little attention has been paid to the identification of modifiable lifestyle habits for its prevention. OBJECTIVE: To explore the association between physical activity and the risk of cognitive impairment and dementia. DESIGN, SETTING, AND SUBJECTS: Data come from a community sample of 9008 randomly selected men and women 65 years or older, who were evaluated in the 1991-1992 Canadian Study of Health and Aging, a prospective cohort study of dementia. Of the 6434 eligible subjects who were cognitively normal at baseline, 4615 completed a 5-year follow-up. Screening and clinical evaluations were done at both waves of the study. In 1996-1997, 3894 remained without cognitive impairment, 436 were diagnosed as having cognitive impairment-no dementia, and 285 were diagnosed as having dementia. MAIN OUTCOME MEASURE: Incident cognitive impairment and dementia by levels of physical activity at baseline. RESULTS: Compared with no exercise, physical activity was associated with lower risks of cognitive impairment, Alzheimer disease, and dementia of any type. Significant trends for increased protection with greater physical activity were observed. High levels of physical activity were associated with reduced risks of cognitive impairment (age-, sex-, and education-adjusted odds ratio, 0.58; 95% confidence interval, 0.41-0.83), Alzheimer disease (odds ratio, 0.50; 95% confidence interval, 0.28-0.90), and dementia of any type (odds ratio, 0.63; 95% confidence interval, 0.40-0.98). CONCLUSION: Regular physical activity could represent an important and potent protective factor for cognitive decline and dementia in elderly persons.

Aged↗
PubMed2001

Reliability and validity of questions about exercise in the Canadian Study of Health and Aging.

Regular exercise in elderly people has beneficial health effects. We examined exercise frequency and intensity from the Canadian Study of Health and Aging Risk Factor Questionnaire (RFQ). The reliability and validity of these two questions individually, and when combined to form a scale, are reported. Agreement between the self-administered RFQ and an interviewer-administered Add-on Study was examined using intraclass correlations, which were 0.80 for frequency (95% CI 0.77-0.82, p < .001) and 0.75 for intensity (95% CI 0.71-0.78, p = .012). Individuals reporting high levels of exercise frequency, intensity, and a combination of the two showed a smaller proportion of adverse health markers than those reporting no regular exercise. Predictive validity assessed by Cox proportional hazards modeling of mortality showed that the high and moderate levels of frequency, intensity, and combined exercise groups differed significantly (all p < .001) from the no exercise group. We have found that these exercise questions, though simple, appear reliable and valid. The finding that even comparatively crude exercise questions can demonstrate an important relationship to death suggests that the signal for exercise is a strong one, and future studies should seek to better examine mechanisms by which exercise benefit is conferred.

Aged↗
PubMed1998

Peer visitor support for family caregivers of seniors with stroke.

The objectives of this nationally funded intervention study were to: (1) implement a home visiting support program for family caregivers of seniors with a recent stroke using experienced peers; (2) monitor, describe, and evaluate the support intervention process; and (3) measure the impact of the peer support intervention on caregivers' perceptions of their social support, burden, stress, and competence and the use of health-care services by stroke survivors. This paper focuses on the first two objectives. Twenty family caregivers were visited initially by a health professional (nurse, occupational therapist) for assessment, and thereafter twice weekly for 12 weeks by a peer (experienced family caregiver). Transcripts of audiotaped post-intervention and delayed post-intervention (3 and 6 months) interviews with participants and the diaries/logs of professionals and peers were subjected to content analysis. Peer visitors offered emotional, informational, and affirmational support to family caregivers. Family caregivers reported that the intervention met their support needs, lessened some of their caregiving demands, and enhanced their confidence and ability to cope.

Aged↗
PubMed1989

Recurrent stenosis by duplex scan following carotid endarterectomy.

Between June 1984 and January 1986, 155 carotid endarterectomies were performed with routine shunting. Serial duplex scanning was performed during an 18-month period on 124 vessels. The results of this duplex scan review revealed the following data: A normal scan was obtained in 87/124 (70.1%). Recurrent stenosis was identified in 35/124 (28.1%), and an occluded vessel was identified in 2/124 (1.6%). Of the total recurrent stenosis group, recurrent stenosis was graded mild in 22/124 (17.7%), moderate in 7/124 (5.6%), and severe in 6/124 (4.8%). Of the 35 vessels with recurrent stenosis by duplex scanning, 22/35 (62.8%) were in female patients, and 13/35 (37.2%) were in male patients. Of the vessels with severe recurrent stenosis, 5/6 (83%) were in female patients. Recurrent stenosis following carotid endarterectomy is more common than appreciated clinically, and female patients in particular may be more prone to recurrent stenosis.

Adult↗
PubMedDate not supplied

Promoting positive affect and diminishing loneliness of widowed seniors through a support intervention.

Seniors are most vulnerable to conjugal bereavement. Although social support buffers the effects of bereavement, widows and widowers have lower levels of social support than married individuals. Self-help/support groups can supplement support from their depleted natural networks. Accordingly, the aim of this demonstration project was to examine the impact of support groups on widowed seniors' loneliness, affect, and perceived support. Four face-to-face support groups for widowed seniors were conducted weekly for a maximum of 20 weeks. Participants completed pretest, posttest, and delayed posttest measures of support need and support satisfaction, positive and negative affect, and loneliness/isolation. The statistically significant impacts of the intervention were enhanced support satisfaction, diminished support needs, and increased positive affect. There was a trend toward decreased social isolation and emotional loneliness. In postintervention semistructured interviews, bereaved seniors reported increased hope, improved skills in developing social relationships, enhanced coping, new role identities, and less loneliness. Community health nurse researchers could conduct randomized controlled trials of face-to-face and telephone support groups for bereaved people of all ages. Community health nurse practitioners could benefit from lessons learned about timing, duration, and selection of sensitive outcomes.

Aged↗