University of Manchester
Frailty and Anabolic Hormones in Ageing Men.
Degree: 2011, University of Manchester
Frailty can be broadly defined as the vulnerable
health status that occurs in older adults. With the ageing
population understanding frailty is becoming an increasingly
important issue. While no consensus exists on the exact definition
of frailty, two models have become prominent in geriatric research.
These are the frailty phenotype, a model that measures frailty
according to the syndromic aggregation of 5 physical criteria and
the frailty index (FI), a broad index of age related health
deficits. While recent years have seen a substantial increase in
research into frailty, there remains a relative paucity of data
from European studies and studies in men. Of the many mechanisms
suggested to contribute to frailty there has been particular
interest in the role of declining levels of anabolic hormones,
partly because replacement of these hormones represents a potential
strategy for managing this condition. The broad aim of this thesis
was to explore the condition of frailty and its relationship to
anabolic hormones, particularly testosterone (T) in ageing European
Men. This project involved analysis of data from 2 studies: The
European Male Ageing Study (EMAS), a longitudinal cohort study of
3369 men from 8 European centres and a trial of T treatment in 262
men with low testosterone and symptoms of frailty. A set of
phenotypic frailty criteria were developed for use in the EMAS,
using this model the prevalence of frailty was 2.6%. This increased
with age from 0.1% in men aged 40-49 up to 6.7% in men aged 70-79.
This model was compared against an FI, the correlation between the
two models was moderate, r=0.41, and both models were related to
incident falling at 2 year follow up; Ordinal OR (95% CI), 3.15
(1.75 to 5.66) for the frailty phenotype and 5.28 (3.35 to 8.32)
for the FI in adjusted analyses. In the hormone analyses frailty
was related to lower free T according to both models, Ordinal OR
(95% CI); 1.19 (1.02 to 1.39) for the phenotype and β-coefficient
(95% CI); 0.006 (0.003 to 0.009) for the FI (FI values range from
0-0.7). Free T was particularly related to the sarcopenia criteria
OR (95% CI); 1.40 (1.09 to 1.80). Frailty was also related to LH,
FSH and SHBG. Deficiency in multiple anabolic hormones was related
to frailty, in adjusted analyses each additional deficiency was
associated with an RRR (95% CI); 1.71 (1.38 to 2.13) increased risk
of phenotypic frailty and a β-coefficient (95% CI); 0.016 (0.012 to
0.02) increase in FI score. The trial analyses focussed on a 6
month post treatment follow up phase. It was found that gains in
lean mass and muscle strength were not maintained at 6 months post
treatment. The adjusted difference between groups at 6 months post
treatment for knee extensor strength was 4.0 (-3.9 to 11.9) Nm
compared to 8.1 (-0.2 to 16.5) Nm at the end of treatment,
similarly the difference in lean mass declined from 1.2 (0.8 to
1.7) kg at end of treatment to 0.3 (-0.1 to 0.8) kg at 6 months
post treatment. In summary, the frailty phenotype was adapted and
validated for use in the EMAS study.…
Advisors/Committee Members: ROBERTS, STEPHEN SA, TAJAR, ABDELOUAHID A, Wu, Frederick, Roberts, Stephen, Tajar, Abdelouahid.
Subjects/Keywords: Ageing; Frailty; Testosterone
to Zotero / EndNote / Reference
APA (6th Edition):
O'Connell, M. (2011). Frailty and Anabolic Hormones in Ageing Men. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:138103
Chicago Manual of Style (16th Edition):
O'Connell, Matthew. “Frailty and Anabolic Hormones in Ageing Men.” 2011. Doctoral Dissertation, University of Manchester. Accessed June 17, 2019.
MLA Handbook (7th Edition):
O'Connell, Matthew. “Frailty and Anabolic Hormones in Ageing Men.” 2011. Web. 17 Jun 2019.
O'Connell M. Frailty and Anabolic Hormones in Ageing Men. [Internet] [Doctoral dissertation]. University of Manchester; 2011. [cited 2019 Jun 17].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:138103.
Council of Science Editors:
O'Connell M. Frailty and Anabolic Hormones in Ageing Men. [Doctoral Dissertation]. University of Manchester; 2011. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:138103