Lifetime Veganism: Osteoporosis and Vertebral fracture

1Thuc Lan Ho-Pham, 2Nguyen ND ,3Thu A. Le, 2Tuan V. Nguyen

*Coauthors:, 1Vu BQ, 3Pham NH, 1Nguyen LP, 1Le TT, 1Doan AT, and 1Tran N.1Pham Ngoc Thach College of Medicine,Ho Chi Minh City, Vietnam, 2Garvan Institute of Medical Research, Sydney, Australia; 3Cho Ray Hospital, Ho Chi Minh City, Vietnam.

OSTEOPOROSIS AND FRACTURE

OSTEOPOROSIS: High prevalence

• 20% postmenopausal women1

• 10% men ( > 50 year-old)1

• Vietnam : 23% postmenopausal women2

OSTEOPOROTIC FRACTURE : High lifetime risk3

• Any fracture 50%

• Hip fracture 17%

• Vertebral fracture 25%

1 Nguyen DN, Nguyen TV. Osteoporosis 3rd edition

2 Nguyen.T.T.Huong, Nguyen TV. New Zealand Bone Miner Soci 2006

3 Nguyen DN, et al. J Bone Miner Res 2007

ROLE OF DIET IN OSTEOPOROSIS PREVENTION

• Prevention is preferable to treatment

• Diet and nutrition are important components in osteoporosis prevention

VEGETARIAN AND OMNIVORE DIETS

Semi/demi vegetarian

Lacto-ovo vegetarian

Lacto vegetarian

Vegan (Asian veg)

VEGANISM AND BONE HEALTH

• Whether lifelong vegetarian diet has any negative effect on bone health, a contentious issue1,2.

• Lack of information about prevalence of osteoporosis and vertebral fracture in postmenopausal Vietnamese women.

1 EMC Lau, et al. JC Nutrition 1998

2 Fontana L, et al. Arch In Med 2005

AIMS

• Examine the association between lifelong vegetarian diet and osteoporosis.

• Estimate the prevalence and risk factors of vertebral fracture in postmenopausal Vietnamese women.

METHODS AND STUDY DESIGN

A cross-sectional study

Vegetarian (Buddhist nuns)

n=105

Omnivoresn=105

• 50+ years old

• From 15 monasteries in Ho Chi Minh City

• Random sample

• 50+ years old

• From various districts in Ho Chi Minh City

• Random sample

OUTCOME MEASUREMENTS

BMD measurement (Hologic QDR 4500).

Lumbar spine

Femoral neck

Total body (eg lean mass and fat mass)

Vertebral fracture (X-ray, Genant’s semi-quantitative method).

COVARIATES

• Anthropometric measurements.

• Daily dietary energy and nutrient intakes (24h recall questionnaire).

• Lifestyle factors.

• Comorbidity (CVD, diabetes, osteoarthritis, etc).

• A history of fall (past 3 months)

• Prior fracture (after the age of 50).

Diet and Bone Mineral Density

Characteristics of participants by dietVegetarians Omnivores P-value

(n=105) (n=105)

Age (y) 62 (10) 62 (10) 0.95

Weight (kg) 53 (9) 54 (7) 0.59

Height (cm) 148 (6) 149 (6) 0.15

BMI (kg/m2) 24 (4) 24 (3) 0.78

Total body fat (kg) 19 (5) 19 (5) 0.77

Total body lean (kg) 32 (5) 33 (4) 0.47

Highest education (n,%) 0.007

≤ Primary 27 (25.7) 28 (26.7)

Secondary 66 (62.9) 48 (45.2)

Tertiary 12 (11.4) 29 (27.6)

Morning exercise (n,%) 82 (78.1) 81 (77.1) 0.86

Coffee drinking (n,%) 28 (26. 7) 48 (45.2) 0.004

Major comorbidity (n,%) 47 (44.8) 52 (49.5) 0.49

Values are mean (SD), unless otherwise specified.

Daily dietary energy and nutrient intakes

Non-vegan Vegan

500

1500

2500

3500

(Kca

l/day

)

(P<0.0001)

Non-vegan Vegan

010

0020

00

(Gra

ms/

day)

(P<0.0001)

Non-vegan Vegan

020

4060

80

(Gra

ms/

day)

(P<0.0001)

Non-vegan Vegan

1030

5070

(Gra

ms/

day)

(P<0.1112)

Non-vegan Vegan

010

2030

4050

(Gra

ms/

day)

(P<0.0001)

Non-vegan Vegan

020

4060

(Gra

ms/

day)

(P<0.2262)

Energy intake Calcium

Animal source protein Vegetable source protein

Vegetable source lipidAnimal source lipid

Whole body Femoral neck Lumbar spine

Vegetarians (n=105)Omnivores (n=105)

Bon

e m

iner

al d

ensi

ty (

g/cm

2 )

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Bone mineral density in vegetarians and omnivores

Values are mean and 95% CI

Prevalence of osteoporosis (T-scores < -2.5) by diet

18.1%

No significant difference in prevalence of osteoporosis between lifetime vegans and non-vegans

Vegans Omnivores

15.2%

Osteoporosis: BMD T-scores ≤-2.5 at the femoral neck

Unit of ↑SD of BMD R-square

change (95% CI)

Femoral neck 0.36

Age (y) +10 -0.5 (0.4, 0.6)

Lean mass (kg) +4 0.3 (0.2, 0.4)

Lumbar spine 0.36

Age (y) +10 -0.5 (0.4, 0.7)

Weight (kg) +8 0.3 (0.1, 0.4)

Animal source protein (g/d) +20 0.2 (0.0, 0.3)

Association between factors and BMD (multivariable analysis)

Bayesian averaging method (BMA) was used to select the best fit model for FNBMD and LSBMD. All potential explainable factors were included in selecting independent factor process.

Morphometric vertebral fracture

Prevalence of vertebral fracture

n % (95% CI)

Any vertebral fracture 48/209 23.0 (17.3, 28.7)

By age group:

50-59 18/106 17.0 (9.8, 24.1)

60-69 10/53 18.9 (8.3, 29.4)

70+ 20/50 40.0 (26.4, 53.6)

By diet:

Buddhist vegetarians 23/104 22.1 (14.1, 30.1)

Non-vegetarians 25/105 23.8 (15.7, 32.0)

Risk factors for vertebral fracture (bivariate analysis)

Factor Unit change OR (95% CI)

Age (y) +10 1.6 (1.1, 2.2)

Weight (kg) +8 1.1 (0.8, 1.6)

BMI (kg/m2) +3 1.3 (0.9, 1.7)

FNBMD (g/cm2) -0.11 1.3 (0.9, 1.8)

LSBMD (g/cm2) -0.14 1.7 (1.2, 2.5)

Prior fracture yes 1.9 (1.0, 3.8)

Back pain yes 1.2 (0.6, 2.4)

Calcium intake (g/d) -370 1.2 (0.9, 1.6)

Vegan yes 0.9 (0.5, 1.7)

There was no significant association between vertebral fracture and other factors

Risk factors for vertebral fracture (multivariable logistic regression analysis)

Factor Unit changeOdds ratio (95% CI)

Age (y) +10 1.2 (1.0, 1.8)

LSBMD (g/cm2) -0.14 1.5 (1.0, 2.2)

Prior fracture yes 1.5 (0.7, 3.1)LSBMD, lumbar spine bone mineral density

Veganism: osteoporosis and vertebral fracture

• Vegetarians:

– much lower dietary energy, protein and calcium intakes than omnivores.

– no adverse effect on bone health, in terms of osteoporosis and vertebral fracture risk.

Osteoporosis and vertebral fracture in postmenopausal Vietnamese women

• Prevalence of vertebral fracture in postmenopausal Vietnamese women was as common as in Caucasian women.

Acknowledgements

I express special thanks to Pro.Nguyen van Tuan for his excellent support this study.

I express deep appreciation to Dr Nguyen Dinh Nguyen and Miss Ha Hai Chau for their kind helping me.

Thanks also to my students for their meticulous assistance.

Thank you!

Back-up slides

Prevalence of osteoporosis

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Thai

Indo

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n

Chines

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Japa

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Korea

n

Austra

lian

Oste

oporo

sis

at

the f

em

ora

l neck (

%)

0

5

10

15

20

25

30

35

1723

30

1510

1710

21

Daily dietary energy and nutrient intakes

Non-vegan Vegan

500

1500

2500

3500

(Kca

l)

Daily energy intake (P<0.0001)

Non-vegan Vegan

050

015

0025

00

(Gra

ms/

day)

Calcium (P<0.0001)

Non-vegan Vegan

020

4060

80

(Gra

ms/

day)

Animal source protein (P<0.0001)

Non-vegan Vegan0

2040

60

(Gra

ms/

day)

Vegetable source protein (P<0.1112)

Non-vegan Vegan

010

2030

4050

(Gra

ms/

day)

Animal source lipid (P<0.0001)

Non-vegan Vegan

020

4060

(Gra

ms/

day)

Vegetable source lipid (P<0.2262)

Association between factors and BMD (univariate analysis)

Variables Unit of ↑ FN BMD ↑ LS BMD

change (SD, 95% CI) (SD, 95% CI)

Age (y) -10 0.5 (0.4, 0.7) 0.5 (0.4, 0.7)

Weight (kg) +8 0.4 (0.2, 0.5) 0.3 (0.2, 0.5)

Height (cm) +6 0.3 (0.2, 0.4) 0.4 (0.2, 0.4)

BMI (kg/m2) +3 0.3 (0.1, 0.4) 0.2 (0.1, 0.4)

Fat mass (kg) +5 0.2 (0.1, 0.3) 0.2 (0.1, 0.3)

Lean mass (kg) +4 0.4 (0.2, 0.5) 0.3 (0.2, 0.5)

Daily dietary intake

Energy (Kcal) +450 0.1 (0.0, 0.2) 0.1 (0.0, 0.3)

Animal source Pr (g) +20 0.0 (-0.1, 0.2) 0.2 (0.0, 0.3)

Vegetable source Pr (g) +12 0.1 (-0.1, 0.2) 0.0 (-0.1, 0.2)

Calcium (g) +370 0.1 (0.0, 0.2) 0.0 (-0.1, 0.2)

Veganism Yes -0.2 (-0.5, 0.1) -0.2 (-0.5, 0.1)

FN, femoral neck; LS, lumbar spine; BMD, bone mineral density

Characteristics of participants by fractureVertebral fracture Non-vertebral fracture P-value

(n=48) (n=161)

Age (y) 65 (11) 61 (9) 0.0065

Weight (kg) 54 (8) 53 (8) 0.4577

Height (cm) 148 (6) 149 (6) 0.2929

BMI (kg/m2) 25 (4) 24 (3) 0.161

Total body fat (kg) 19 (5) 19 (5) 0.4387

Total body lean (kg) 33 (4) 32 (4) 0.3391

FNBMD (g/cm2) 0.61 (0.13) 0.64 (0.11) 0.115

LSBMD (g/cm2) 0.70 (0.14) 0.78 (0.14) 0.0016

Daily dietary intake:

Energy (Cal)* 1320 (1007, 1538) 1266 (1051, 1547) 0.7566

Animal source protein (g)* 24 (9, 33) 31 (18, 41) 0.0955

Non-animal protein (g)* 29 (22, 35) 26 (22, 35) 0.6058

Calcium (g)* 432 (310, 645) 422 (267, 641) 0.4263

Values are mean(SD), unless otherwise specified* Median (Q1,Q3)

Vertebral fracture Non-vertebral fracture P-value

(n=48) (n=161)

Education: 0.3579

≤ Primary 14 (29.2) 41 (25.6)

Secondary 28 (58.3) 84 (52.5)

Tertiary 6 (12.5) 35 (21.9)

Morning exercise 37 (77.1) 125 (78.1) 0.8788

Hypertension 17 (35.4) 43 (26.9) 0.2519

CVD 1 (2.1) 6 (3.8) 1.000

Diabetes 3 (6.3) 11 (6.9) 0.8795

Arthritis 9 (18.8) 29 (18.1) 0.9217

Back pain 26 (54.2) 73 (45.6) 0.2987

Prior fracture 15 (31.3) 31 (19.3) 0.0790

A history of fall 4 (8.3) 17 (10.7) 0.6439

Characteristics of participants by fracture (cont.)

Values are n (%)