@article {639, title = {Frailty in older adults: evidence for a phenotype.}, journal = {J Gerontol A Biol Sci Med Sci}, volume = {56}, year = {2001}, month = {2001 Mar}, pages = {M146-56}, abstract = {

BACKGROUND: Frailty is considered highly prevalent in old age and to confer high risk for falls, disability, hospitalization, and mortality. Frailty has been considered synonymous with disability, comorbidity, and other characteristics, but it is recognized that it may have a biologic basis and be a distinct clinical syndrome. A standardized definition has not yet been established.

METHODS: To develop and operationalize a phenotype of frailty in older adults and assess concurrent and predictive validity, the study used data from the Cardiovascular Health Study. Participants were 5,317 men and women 65 years and older (4,735 from an original cohort recruited in 1989-90 and 582 from an African American cohort recruited in 1992-93). Both cohorts received almost identical baseline evaluations and 7 and 4 years of follow-up, respectively, with annual examinations and surveillance for outcomes including incident disease, hospitalization, falls, disability, and mortality.

RESULTS: Frailty was defined as a clinical syndrome in which three or more of the following criteria were present: unintentional weight loss (10 lbs in past year), self-reported exhaustion, weakness (grip strength), slow walking speed, and low physical activity. The overall prevalence of frailty in this community-dwelling population was 6.9\%; it increased with age and was greater in women than men. Four-year incidence was 7.2\%. Frailty was associated with being African American, having lower education and income, poorer health, and having higher rates of comorbid chronic diseases and disability. There was overlap, but not concordance, in the cooccurrence of frailty, comorbidity, and disability. This frailty phenotype was independently predictive (over 3 years) of incident falls, worsening mobility or ADL disability, hospitalization, and death, with hazard ratios ranging from 1.82 to 4.46, unadjusted, and 1.29-2.24, adjusted for a number of health, disease, and social characteristics predictive of 5-year mortality. Intermediate frailty status, as indicated by the presence of one or two criteria, showed intermediate risk of these outcomes as well as increased risk of becoming frail over 3-4 years of follow-up (odds ratios for incident frailty = 4.51 unadjusted and 2.63 adjusted for covariates, compared to those with no frailty criteria at baseline).

CONCLUSIONS: This study provides a potential standardized definition for frailty in community-dwelling older adults and offers concurrent and predictive validity for the definition. It also finds that there is an intermediate stage identifying those at high risk of frailty. Finally, it provides evidence that frailty is not synonymous with either comorbidity or disability, but comorbidity is an etiologic risk factor for, and disability is an outcome of, frailty. This provides a potential basis for clinical assessment for those who are frail or at risk, and for future research to develop interventions for frailty based on a standardized ascertainment of frailty.

}, keywords = {Aged, Aged, 80 and over, Cohort Studies, Disabled Persons, Fatigue, Female, Frail Elderly, Humans, Incidence, Male, Muscle Weakness, Phenotype, Prevalence, Sex Distribution, United States, Weight Loss}, issn = {1079-5006}, doi = {10.1093/gerona/56.3.m146}, author = {Fried, L P and Tangen, C M and Walston, J and Newman, A B and Hirsch, C and Gottdiener, J and Seeman, T and Tracy, R and Kop, W J and Burke, G and McBurnie, M A} } @article {6810, title = {Coagulation factor~XII genetic variation, ex~vivo thrombin generation, and stroke risk in the elderly: results from the Cardiovascular Health Study.}, journal = {J Thromb Haemost}, volume = {13}, year = {2015}, month = {2015 Oct}, pages = {1867-77}, abstract = {

BACKGROUND: The relationships of thrombin generation (TG) with cardiovascular disease risk are underevaluated in population-based cohorts.

OBJECTIVES: To evaluate the relationships of TG influenced by the contact and tissue factor coagulation pathways ex~vivo with common single-nucleotide polymorphisms (SNPs) and incident cardiovascular disease and stroke.

PATIENTS/METHODS: We measured peak TG (pTG) in baseline plasma samples of Cardiovascular Health Study participants (n~=~5411), both with and without inhibitory anti-factor~XIa antibody (pTG/FXIa(-) ). We evaluated their associations with ~~50~000 SNPs by using the IBCv2 genotyping array, and with incident cardiovascular disease and stroke events over a median follow-up of 13.2~years.

RESULTS: The minor allele for an SNP in the FXII gene (F12), rs1801020, was associated with lower pTG in European-Americans (β~=~-~34.2~{\textpm}~3.5~nm; P~=~3.3~{\texttimes}~10(-22) ; minor allele frequency [MAF]~=~0.23) and African-Americans (β~=~-~31.1~{\textpm}~7.9~nm; P~=~9.0~{\texttimes} 10(-5) ; MAF~=~0.42). Lower FXIa-independent pTG (pTG/FXIa(-) ) was associated with the F12 rs1801020 minor allele, and higher pTG/FXIa(-) was associated with the ABO SNP rs657152 minor allele (β~=~16.3~nm; P~=~4.3~{\texttimes}~10(-9) ; MAF~=~0.37). The risk factor-adjusted ischemic stroke hazard ratios were 1.09 (95\% confidence interval CI~1.01-1.17; P~=~0.03) for pTG, 1.06 (95\% CI~0.98-1.15; P~=~0.17) for pTG/FXIa(-) , and 1.11 (95\% CI~1.02-1.21; P~=~0.02) for FXIa-dependent pTG (pTG/FXIa(+) ), per one standard deviation increment (n~=~834 ischemic strokes). In a multicohort candidate gene analysis, rs1801020 was not associated with incident ischemic stroke (β~=~-~0.02; standard error~=~0.08; P~=~0.81).

CONCLUSIONS: These results support the importance of contact activation pathway-dependent TG as a risk factor for ischemic stroke, and indicate the importance of F12 SNPs for TG ex~vivo and in~vivo.

}, keywords = {African Americans, Age Factors, Aged, Blood Coagulation, Brain Ischemia, European Continental Ancestry Group, Factor XII, Female, Gene Frequency, Genetic Predisposition to Disease, Humans, Incidence, Male, Phenotype, Polymorphism, Single Nucleotide, Prospective Studies, Risk Assessment, Risk Factors, Stroke, Thrombin, Time Factors, United States}, issn = {1538-7836}, doi = {10.1111/jth.13111}, author = {Olson, N C and Butenas, S and Lange, L A and Lange, E M and Cushman, M and Jenny, N S and Walston, J and Souto, J C and Soria, J M and Chauhan, G and Debette, S and Longstreth, W T and Seshadri, S and Reiner, A P and Tracy, R P} }