Kate Ward's presentation from Osteoporosis 2016: Relationships between muscle function and bone microarchitecture in the Hertfordshire cohort study. Find out more at: https://nos.org.uk/conference

1. Relationships between muscle function
and bone microarchitecture in the
Hertfordshire Cohort Study
KA Ward, MH Edwards, K Jameson, S Shaw, H Syddall, C
Cooper, EM Dennison
MRC Lifecourse Epidemiology Unit, University of Southampton
MRC Elsie Widdowson Laboratory, Cambridge

2. Musculoskeletal ageing
• By 2050 2 milliards of people aged
>65 years, c.f. 600 million today
• Osteoporosis: 1 in 2 women, 1 in 5
men > 50 yrs.
• Sarcopenia: No defined consensus,
IWGS, EWGSOP, FNIH.
• Healthcare costs:
• OP - £2million/day, £5 billion/yr
• Sarcopenia - >$18 billion in the US
2001
• Sarcopenia, falls and fracture
prevention
Hertfordshire Cohort Study
• Lean mass indices – cortical area
and thickness
• Fat mass indices – trabecular
density, number independent of LMI
• Compartmental effects cortical vs
trabecular bone, lean mass vs. fat
• Muscle strength – mass, anatomy
(fibre composition, IMAT, pennation
angle), force and power generating
capacity
Edwards MH, PhD Thesis 2014
Edwards 2015, Bone, 81 145-151

3. Jumping mechanography
MuscleCSA(cm3)
Chairrise(s-1)
Age (years)
JMPower(Wkg-1)
Age (years)Age (years)
Rittweger, 2004, J Am J Geriatr Soc, 52:128–131

4. Power – functional capacity, e.g arresting a fall, walk speed
Force – measure of the load to bone
Efficiency – how well you utilise force to generate power

5. Methods
• 184 (144) men and 166 (104) women,
mean (SD) age M 75.9 (2.4), F 75.9
(2.6)
• HRpQCT of the tibia and radius (X-
Treme I™, Scanco Medical)
• 2-leg countermovement jump to
assess jump force and power
(Leonardo ™, Novotec Medical)
• Linear regression models, males and
females separately
• age, weight, height
• social class, smoking status,
calcium intake, hormone
replacement use and years since
menopause in women.

6. Jump power
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Males (unadj)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Jump power
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Females (103)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Power
* * ** * *
Adjusted for age, height and weight

7. Jump power
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Males (142)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Males (127)
Jump power
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Females (103)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Females (90)
Power
* * * **
Adjusted for age, height, weight, social class, smoking status, calcium intake,
hormone replacement use and years since menopause in women

8. Force
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Males (unadj)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Force
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Females (103)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Force
** * * * * * ***
Adjusted for age, height and weight

9. Force
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Males (144)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Males (128)
Force
HRpQCT
SDper1SDchangeinpower
-0.5
0.0
0.5
1.0
Females (103)
Totarea
Cortarea
Trabarea
Cortthk
CortBMD
Cortpor
TrabBMD
TrabNo
Trabthk
Females (90)
Force
*
Adjusted for age, height, weight, social class, smoking status, calcium intake,
hormone replacement use and years since menopause in women

10. Conclusions
• In women, greater muscle power and force had more
cortical and trabecular bone
• In men, consistent negative associations with porosity
were found, suggesting lower turnover with greater
power
• No associations between pQCT and jump parameters
(data not shown) at the distal or diaphyseal sites
• LMI and FMI are more consistent predictors of bone
microarchitecture in older adults (function vs. mass).
• Findings are less strong and more inconsistent than in
other cohorts who are in general younger and have a
wider range of ages.

11. Acknowledgements
Co-authors
Mark Edwards, Cyrus Cooper, Elaine Dennison
Karen Jameson, Sarah Shaw, Holly Sydall
Funding
Medical Research Council
Study Participants
Hertfordshire Cohort Study

12. Lean mass indices: men
Unadjusted Fully adjusted
N
Regression
coefficient
95% CI p-value N
Regression
coefficient
95% CI p-value
tibia total area
135 -0.035 (-0.207, 0.136) 0.684 122 -0.041 (-0.230, 0.148) 0.667
tibia cortical
area 136 0.499 (0.349, 0.648) <0.001 123 0.524 (0.358, 0.691) <0.001
tibia trabecular
area 137 -0.125 (-0.296, 0.046) 0.152 123 -0.137 (-0.322, 0.048) 0.146
tibia apparent
cortical
thickness 136 0.437 (0.282, 0.593) <0.001 123 0.462 (0.295, 0.628) <0.001
tibia cortical
BMD 136 0.148 (-0.022, 0.318) 0.087 123 0.105 (-0.077, 0.287) 0.255
tibia cortical
porosity 136 0.023 (-0.141, 0.187) 0.783 123 0.082 (-0.097, 0.261) 0.365
tibia trabecular
density 137 0.132 (-0.035, 0.299) 0.119 123 0.172 (-0.010, 0.354) 0.064
tibia trabecular
number 137 0.262 (0.110, 0.415) 0.001 123 0.259 (0.088, 0.430) 0.003
tibia trabecular
thickness 137 -0.065 (-0.235, 0.106) 0.453 123 -0.008 (-0.191, 0.174) 0.927
Results are an SD change per one SD change in predictor
Adjusted for age, height, weight, social class, smoker status, alcohol consumption, activity, dietary calcium and HRT use and years since
menopause in women

13. Lean mass indices: women
Unadjusted Fully adjusted
N
Regression
coefficient
95% CI p-value N
Regression
coefficient
95% CI p-value
tibia total area
100 0.134 (-0.065, 0.333) 0.184 91 0.087 (-0.143, 0.317) 0.454
tibia cortical
area 100 0.489 (0.313, 0.664) <0.001 91 0.498 (0.293, 0.704) <0.001
tibia trabecular
area 100 0.060 (-0.140, 0.261) 0.553 91 0.012 (-0.222, 0.245) 0.921
tibia apparent
cortical
thickness 100 0.314 (0.123, 0.505) 0.002 91 0.339 (0.115, 0.563) 0.004
tibia cortical
BMD 100 0.248 (0.051, 0.445) 0.014 91 0.271 (0.046, 0.496) 0.019
tibia cortical
porosity 100 -0.132 (-0.333, 0.070) 0.197 91 -0.143 (-0.375, 0.088) 0.221
tibia trabecular
density 100 0.007 (-0.194, 0.208) 0.946 91 0.051 (-0.186, 0.289) 0.668
tibia trabecular
number 100 0.138 (-0.063, 0.339) 0.175 91 0.155 (-0.071, 0.381) 0.177
tibia trabecular
thickness 100 -0.073 (-0.272, 0.126) 0.469 91 -0.025 (-0.259, 0.210) 0.835
Results are an SD change per one SD change in predictor
Adjusted for age, height, weight, social class, smoker status, alcohol consumption, activity, dietary calcium and HRT use and years since
menopause in women