David Bryan Hogan

Dr. David Bryan Hogan

orcid

Research Focus & Metrics

Academic Career Length

46Years (1981-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 August 2005 in Canadian Medical Association Journal
Verified
Journal Article
Open access
PDF file
KRKenneth Rockwood
Kenneth Rockwood
XSXiaowei Song
Xiaowei Song
CMChris MacKnight
Chris MacKnight
HBHoward Bergman
Howard Bergman
DHDavid Bryan Hogan
David Bryan Hogan
AMArnold Mitnitski
Arnold Mitnitski
Background: There is no single generally accepted clinical definition of frailty. Previously developed tools to assess frailty that have been shown to be predictive of death or need for entry into an institutional facility have not gained acceptance among practising clinicians. We aimed to develop a tool that would be both predictive and easy to use. Methods: We developed the 7-point Clinical Frailty Scale and applied it and other established tools that measure frailty to 2305 elderly patients who participated in the second stage of the Canadian Study of Health and Aging (CSHA). We followed this cohort prospectively; after 5 years, we determined the ability of the Clinical Frailty Scale to predict death or need for institutional care, and correlated the results with those obtained from other established tools. Results: The CSHA Clinical Frailty Scale was highly correlated (r = 0.80) with the Frailty Index. Each 1-category increment of our scale significantly increased the medium-term risks of death (21.2% within about 70 mo, 95% confidence interval [CI] 12.5%–30.6%) and entry into an institution (23.9%, 95% CI 8.8%–41.2%) in multivariable models that adjusted for age, sex and education. Analyses of receiver operating characteristic curves showed that our Clinical Frailty Scale performed better than measures of cognition, function or comorbidity in assessing risk for death (area under the curve 0.77 for 18-month and 0.70 for 70-month mortality). Interpretation: Frailty is a valid and clinically important construct that is recognizable by physicians. Clinical judgments about frailty can yield useful predictive information.

1 July 2007 in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences
Verified
Journal Article
Open access
PDF file
HBHoward Bergman
Howard Bergman
LFLuigi Ferrucci
Luigi Ferrucci
JGJack Guralnik
Jack Guralnik
DHDavid Bryan Hogan
David Bryan Hogan
SHSilvia Hummel
Silvia Hummel
CWChristina Wolfson
Christina Wolfson
Clinicians and researchers have shown increasing interest in frailty. Yet, there is still considerable uncertainty regarding the concept and its definition. In this article, we present perspectives on key issues and controversies discussed by scientists from 13 different countries, representing a diverse range of disciplines, at the 2006 Second International Working Meeting on Frailty and Aging. The following fundamental questions are discussed: What is the distinction, if any, between frailty and aging? What is its relationship with chronic disease? Is frailty a syndrome or a series of age-related impairments that predict adverse outcomes? What are the critical domains in its operational definition? Is frailty a useful concept? The implications of different models and approaches are examined. Although consensus has yet to be attained, work accomplished to date has opened exciting new horizons. The article concludes with suggested directions for future research.

1 January 1999 in The Lancet
Verified
Journal Article
Closed access
KRKenneth Rockwood
Kenneth Rockwood
KSKaren Stadnyk
Karen Stadnyk
CMChris MacKnight
Chris MacKnight
IMIan McDowell
Ian McDowell
RHRéjean Hébert
Réjean Hébert
DHDavid Bryan Hogan
David Bryan Hogan

1 September 2009 in Canadian Journal on Aging / La Revue canadienne du vieillissement
Verified
Journal Article
Closed access
PDF file
PRParminder Raina
Parminder Raina
CWChristina Wolfson
Christina Wolfson
SKSusan A. Kirkland
Susan A. Kirkland
LGLauren E. Griffith
Lauren E. Griffith
MOMark Oremus
Mark Oremus
KBKevin Brazil
Kevin Brazil
RÉSUMÉ: Les Canadiens vivent plus longtemps et les personnes plus âgées composent une part croissante de la population (14% en 2006, projeté d’atteindre 20% d’ici 2021). L’Étude longitudinale canadienne sur le vieillissement (ÉLCV) est une étude longitudinale nationale portant sur le développement adulte et le vieillissement qui recrutera 50 000 Canadien(ne)s âgé(e)s de 45 à 85 ans et qui les suivra pendant au moins 20 ans. Tous les participants fourniront un ensemble d’informations communes sur plusieurs aspects de la santé et du vieillissement, et 30 000 passeront un examen approfondi couplé au don de spécimens biologiques (sang et urine). L’ÉLCV deviendra une source de données riches pour l’étude d’inter-relations complexes entre les facteurs biologiques, physiques, psychosociaux et sociaux qui affectent le vieillissement en santé.

1 January 2017 in JAMA Psychiatry
Verified
Journal Article
Open access
PDF file
ZIZahinoor Ismail
Zahinoor Ismail
HEHeba Elbayoumi
Heba Elbayoumi
CFCorinne E. Fischer
Corinne E. Fischer
DHDavid Bryan Hogan
David Bryan Hogan
CMColleen P. Millikin
Colleen P. Millikin
KFKirsten M. Fiest
Kirsten M. Fiest
Depression commonly occurs in association with mild cognitive impairment (MCI).1- 3 Individuals with MCI and depression perform more poorly on immediate and delayed memory tasks compared with nondepressed patients with MCI.4 Further, evidence suggests that depression confers a higher rate of progression along the neurodegenerative spectrum from MCI to dementia; a systematic review and meta-analysis5 of 18 studies determined the pooled relative risk of progressing to dementia was 1.28 (P = .003) in the group of patients with MCI with depressive symptoms compared with the those with MCI with no depressive symptoms. Even subsyndromal symptoms of depression have been identified as a significant factor associated with poorer function and quality of life in patients with MCI as well as a higher progression rate to dementia.6- 8 Thus, appropriate screening strategies for depression and depressive symptoms are paramount in identifying what is a significant risk factor for cognitive, functional, and behavioral outcomes in those who are cognitively impaired.

1 December 2004 in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences
Verified
Journal Article
Open access
PDF file
KRKenneth Rockwood
Kenneth Rockwood
SHSusan E Howlett
Susan E Howlett
CMChris MacKnight
Chris MacKnight
BBB. Lynn Beattie
B. Lynn Beattie
HBHoward Bergman
Howard Bergman
IMIan McDowell
Ian McDowell
Background. Frailty and fitness are important attributes of older persons, but population samples of their prevalence, attributes, and outcomes are limited. Methods. The authors report data from the community-dwelling sample (n = 9008) of the Canadian Study of Health and Aging, a representative, 5-year prospective cohort study. Fitness and frailty were determined by self-reported exercise and function level and testing of cognition. Results. Among the community-dwelling elderly population, 171 per 1000 were very fit and 12 per 1000 were very frail. Frailty increased with age, so that by age 85 years and older, 44 per 1000 were very frail. The risk for adverse health outcomes increased markedly with frailty: Compared with older adults who exercise, those who were moderately or severely frail had a relative risk for institutionalization of 8.6 (95% confidence interval, 4.9 to 15.2) and for death of 7.3 (95% confidence interval, 4.7 to 11.4). These risks persist after adjustments for age, sex, comorbid conditions, and poor self-rated health. At all ages, men reported higher levels of exercise and less frailty compared with women. Decreased fitness and increased frailty were also associated with poor self-ratings of health (42% in the most frail vs 7% in the most fit), more comorbid illnesses (6 vs 3), and more social isolation (34% vs 29%). Conclusions. Fitness and frailty form a continuum and predict survival. Exercise influences survival, even in old age. Relative fitness and frailty can be determined quickly in a clinical setting, are potentially useful markers of the risk for adverse health outcomes, and add value to traditional medical assessments that focus on diagnoses.