1. Curr Aging Sci. 2009 Dec;2(3):193-9.
Mortality according to a prior assessment of biological age.
Bulpitt CJ, Antikainen RL, Markowe HL, Shipley MJ.
Section of Care of the Elderly, Imperial College, London.
BACKGROUND: Measures of biological age have not been proven to predict mortality.
This study examines whether measuring biological age improves the prediction of
METHODS: Prospective study from 1981 to 2001 of 397 male London Civil Servants.
Two indices of biological ageing were calculated.
RESULTS: 60 men died and both indices of biological ageing were related to
survival. In a model that mutually adjusted for both chronological and biological
age, biological age using index one was statistically significant with a hazard
ratio (HR) of 1.11 per year of age (95% confidence interval 1.01 - 1.21, P=0.03).
The useful components of the measures of biological ageing were systolic blood
pressure (HR 1.31 for 1SD), albumin, and, to a lesser degree, Erythrocyte
Sedimentation Rate (ESR). Greying of the hair, skin inelasticity, arcus senilis,
and baldness were not predictors of mortality as measured by our methods.
Similarly serum cholesterol, creatinine, calcium and urate could be excluded. A
modified index was developed including systolic pressure, ESR, urea, albumin, and
bilirubin and had a sensitivity of 78% and specificity of 51% in predicting
subjects who died.
CONCLUSION: This study represents 'proof of principle' in demonstrating the
utility and validity of measuring biological age. The modified index needs to be
PMID: 20021413 [PubMed - indexed for MEDLINE]
2. BMJ. 2009 Dec 10;339:b5262.
Perceived age as clinically useful biomarker of ageing: cohort study.
Christensen K, Thinggaard M, McGue M, Rexbye H, Hjelmborg JV, Aviv A, Gunn D, van
der Ouderaa F, Vaupel JW.
Danish Twin Registry and Danish Aging Research Center, Institute of Public
Health, University of Southern Denmark, DK-5000 Odense C, Denmark.
OBJECTIVE: To determine whether perceived age correlates with survival and
important age related phenotypes.
DESIGN: Follow-up study, with survival of twins determined up to January 2008, by
which time 675 (37%) had died.
SETTING: Population based twin cohort in Denmark.
PARTICIPANTS: 20 nurses, 10 young men, and 11 older women (assessors); 1826 twins
MAIN OUTCOME MEASURES: Assessors: perceived age of twins from photographs. Twins:
physical and cognitive tests and molecular biomarker of ageing (leucocyte
RESULTS: For all three groups of assessors, perceived age was significantly
associated with survival, even after adjustment for chronological age, sex, and
rearing environment. Perceived age was still significantly associated with
survival after further adjustment for physical and cognitive functioning. The
likelihood that the older looking twin of the pair died first increased with
increasing discordance in perceived age within the twin pair-that is, the bigger
the difference in perceived age within the pair, the more likely that the older
looking twin died first. Twin analyses suggested that common genetic factors
influence both perceived age and survival. Perceived age, controlled for
chronological age and sex, also correlated significantly with physical and
cognitive functioning as well as with leucocyte telomere length.
CONCLUSION: Perceived age-which is widely used by clinicians as a general
indication of a patient's health-is a robust biomarker of ageing that predicts
survival among those aged >or=70 and correlates with important functional and
molecular ageing phenotypes.
PMID: 20008378 [PubMed - indexed for MEDLINE]
Edited by Brett Black, 19 February 2012 - 11:34 AM.