Effect of past and present lifestyle habits and nutrition on calcaneal quantitative osteo-sono index in pre- and post-menopausal females

doi:10.4236/health.2010.22019

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Vol.2, No.2, 124-130 (2010)

doi:10.4236/health.2010.22019

SciRes

Health

Effect of past and present lifestyle habits and nutrition

on calcaneal quantitative osteo-sono index in pre- and

post-menopausal females

Masakatsu Nakada1, Shinichi Demura2

1National Defense Academy, Kanagawa, Japan; nakada@nda.ac.jp

2Graduate school of Natural Science & Technology, Kanazawa University, Kanazawa, Japan

Received 4 November 2009; revised 14 December 2009; accepted 17 December 2009.

ABSTRACT

This study is examined the effect of past and

present lifestyle habits and nutrition on the os-

teo-sono assessment index (OSI) in pre- and

post-menopausal females. The subjects were

200 premenopausal females (38.8±10.3years)

and 156 postmenopausal females (59.2±5.9 ye-

ars). BMD (Body mineral density) was estimated

by right-calcaneal OSI using an ultrasonic

transmission method with an AOS-100 device

(ALOKA). The number of postmenopau- sal fe-

males in the close examination and guidance

required groups (80 cases: 51.3 %) (OSI < 2.428)

was significantly higher than that of premeno-

pausal females (44 cases: 22.0 %) (χ2＝33.105:

P<0.000).

In premenopausal females, the proportion of

subjects that had not taken vitamin D in the past

(in junior high school and high school) was

significantly higher in the close examination-

guidance required group (OSI < 2.428) than in

the normal group (OSI ≧ 2.428). However, in

postmenopausal females, there was no signifi-

cant difference in past and present lifestyle

habits and nutrition between the close exami-

nation-guidance required group and the normal

group. In premenopausal females, it was deter-

mined that the intake of vitamin D during pu-

berty increased the absorption of calcium sig-

nificantly.

Keywords: Lifestyle and Nutrition Habits, Osteo-Sono

Assessment Index, Pre and Postmenopausal Females

1. INTRODUCTION

The occurrence of osteoporosis with bone-thinning and

brittle bones is high in elderly people [1-3]. The compli-

cations of fractures limit daily activities (ADL) and re-

duce the quality of life (QOL) of the affected individuals

[4-6]. Even when the level of bone loss is below normal

(osteopenia), the risk of fractures is high [5]. Females in

particular are prone to have osteoporosis and should pay

particular attention to the increased risk of a nutritionally

deficient diet [6,7].

On the other hand, the significance of healthy eating

habits in addition to exercise to maintain and increase

BMD has been established [1,8]. In females, bone mass

increases during puberty with skeletal growth and peaks

from the late teens into the twenties. Afterwards, bone

mass is merely maintained from the late thirties to early

forties [5,6]. Bone mass density peaks during youth.

Increased BMD through proper nutrition, exercise, ex-

posure to sun, etc. are all effective measures for pre-

venting osteoporosis [2]. Hence, it will be necessary to

correlate not only present conditions, but also life style

habits during youth. Aging is a significant factor which

affects BMD. However, the effects of lifestyle habits (the

amount of sleep and alcohol consumption, etc.) and nu-

trition on the bone mineral density in females have been

studied specifically in elderly people and young students

[1,2,7,9,10]. However, the effects of lifestyle habits

should be researched for people of a wider age range. On

the other hand, the bone mass of postmenopausal females

decreases markedly with a rapid decline in estrogen levels

[11]. Hence, studies on the BMD in females should be

considered from the onset of menopause. This study

examined the effects of past and present lifestyle habits

and nutrition on the osteo-sono assessment index (OSI) in

pre- and post-menopausal females from age 20 to 70.

2. METHODS

2.1. Subjects

Subjects were 200 premenopausal females (38.8±10.3

years) and 156 postmenopausal females (59.2±5.9 years).

Table 1 shows the number of subjects, and their mean

heights and weights, at each age level. Written informed

consent was obtained from all subjects after a full ex-

M. Nakada et al. / HEALTH 2 (2010) 124-130

125

planation of the experimental purpose and protocol.

2.2. Measurement of Osteo-Sono

Assessment Index (OSI) and Setting

of OSI Group

BMD was estimated by the right-calcaneus using an

ultrasonic transmission method with an AOS-100 device

(ALOKA). The calcaneal osteo-sono assesment used the

osteo-sono assesment index (OSI: TI×SOS2）by calcu-

lating speed of sound (SOS) of ultrasonic transmission in

the calcaneus and the transmission index (TI) as de-

scribed previously [12,13].

The quantitative assessment of bones has generally

been performed by Dual X-ray absorptiometry (DXA）

and quantitative ultrasound (QUS) [14]. The DXA can

measure the total body bone mineral density and is main-

ly used for precise measurement after screening tests [5].

The QUS is very practical and safe without the effects of

radiation [5]. The OSI by AOS-100 has high reliability

[14]. Thus, this study used an AOS-100 by QUS. The

Japan Osteoporosis Foundation [5] classified females into

a close examination (OSI < 80% of an average OSI =

2.158), a guidance required group (2.158 ≦ OSI < 90%

of an average OSI = 2.428) and a normal group (OSI ≧

2.428) based on an average OSI (OSI = 2.698) of females

between 20 and 44 years old by osteo-sono assessment

criteria. In this study, we combined the former two groups

considering a sample size of each age level and compared

the close examination and guidance required group (OSI

< 2.428 ) with the normal group (OSI ≧2.428 ).

2.3. Lifestyle and Nutrition Habits

Questionnaire

At present, factors found to be involved in BMD by a

large-scale prospective cohort study (Japanese Popula-

tion-Based Osteoporosis (JPOS) Study) have been ex-

amined [15,16]. These prospective cohort studies have

the advantage of being prospectively able to measure the

predictor, but also require considerable time [17]. The

present study is equivalent to a retrospective cohort study

[17] and while recall bias may affect the conclusions,

useful findings can be identified at an earlier stage.

The study evaluated past and present lifestyle habits

and nutrition by questionnaires. The survey was carried

out just before a measurement of OSI. Naka et al. [2]

selected menopause, regular milk consumption, intensity

of physical exercise, and awareness of eating habits and

physical activity as lifestyle habits. Tomita selected

breakfast habits and regular consumption of milk and

dairy products, fish and shellfish, meat products etc.

during childhood and later years (about 6 – 15 yr) as well

as eating habits. Elgán et al. [18] selected 10 items (diet-

ary habits (i.e. sugar, fat, fiber, and fruit and vegetables),

physical activity, smoking habits, alcohol consumption,

Table 1. Physique of subjects.

NMeanSD Mean SD

20 s44161.05.053.85.5

30 s61158.85.253.47.2

40 s76158.35.253.98.1

50 s104156.64.854.26.5

60 s62154.75.752.87.9

70 s9152.34.252.36.6

Height (cm)Weight (kg)

time spent outdoors etc.) as lifestyle habits. The Japan

Osteoporosis Foundation [5] coffee, milk, dairy products,

fish, meat, soy products, green and yellow vegetables,

and natto as meal and articles of taste items for their

interview sheet. Referring to the above, this study se-

lected the following 9 items to investigate present eating

habits: (1) sleep duration, (2) frequency of alcohol con-

sumption, (3) smoking habits, (4) intervals without meals,

(5) regular consumption of dairy products (milk, cheese,

yogurt, etc.), (6) intake of calcium supplements, (7) in-

take of vitamin D (fish, chicken egg, fungi), (8) intake of

instant food (instant noodles, instant coffee, etc.), and (9)

frequency and length of exposure to sun.

The agreement rates of 9 question items by the test-

retest method of 59 subjects ranged from 0.559 – 0.983.

Their κ coefficients [19] ranged from 0.287 (P=0.010) -

0.890 (P=0.000) and any value was significant. As stated,

the subjects’ past lifestyle habit (in junior high school and

high school) regarding (1) amount of sleep, (2) intervals

without meals, (3) intake of dairy products, (4) intake of

vitamin D, and (5) intake of instant food were among the

above 9 items surveyed.

2.3.2. Data Analysis

Both groups were classified into pre- and

post-menopausal females, cross tabulations of the fre-

quency of past and present lifestyle habits and nutrition

were made, and then independent tests were performed.

When a significant difference emerged, residual analysis

was used. A probability level of 0.05 was indicated sta-

tistical significance.

3. RESULTS

Figure 1 show the results of the osteo-sono assessment

index (OSI). The number of postmenopausal females in

the close examination and guidance required groups (OSI

< 2.428) was significantly higher than that (44 cases:

22.0%) of premenopausal females (χ2＝33.105: P<0.000).

The number of people in the close examination and

guidance required groups increased with age, particularly

in people 50 years and older.

Table 2 (premenopausal females) and Table 3 (post-

menopausal females) show cross tabulations by the fre-

M. Nakada et al. / HEALTH 2 (2010) 124-130

126

Table 2. Present lifestyle and nutrition habits and the OSI of premenopausal females.

Sleeping timeLess than

6 hours

More than 6

hours - less

than 7 hours

More than 7

hours - less

than 8 hours

More than 8

hours

ｐφ

CEGR 10(-1.04) 29(2.39)4（

-2.05

)

1（

0.96）7.891 0.048*0.20

Normal48(1.04) 71(-2.39)36 （

2.05

)

1（

-0.96）

Alcohol intakeNo 1 - 3 times a

month

1 - 3 times a

wee

nearly ever

CEGR 1986107.760.051 0.20

Normal5062 22 21

Smoking NoHave a habitQuit

CEGR 35450.602 0.740.06

Normal 1271612

Skip a mealNoBreakfast LunchSupper

CEGR 355001.664 0.6450.09

Normal 1251824

Intake of dairy prodctsNo 1 - 3 times a

month

4 –

7 times a

wee

CEGR 320210.630.73 0.06

Normal 156279

Intake of Ca supplementNoRarely Continuous

CEGR 33730.564 0.7540.05

Normal 1103114

Intake of vitamin DNo 1 - 3 times a

wee

4 –

7 times a

wee

CEGR 525142.200 0.333 0.11

Normal 89454

Intake of instant foodNo 1 - 3 times a

month

More than

once a wee

CEGR 514251.816 0.4030.10

Normal 275671

Sunbathing No 1 - 3 times a

wee

More than 4

times a week

CEGR 1415151.5570.459 0.09

Normal 396846

Note）

CEGR:close examination or guidance required group, *：P<0.05,

Result of OSI

Number shown in parenthese is the Z score of residual analysis.

13.5

3.5

44.4

19.4

8.7

1.3

1.6

2.3

37.8

18.5

44.4

35.5

39.4

19.7

14.8

11.4

48. 7

11.1

45.2

51.9

65.8

83.6

86.4

0%20% 40% 60% 80%100%

Postmenopausal

Premenopausal

70 s

60 s

50 s

40 s

30 s

20 s

examination

required

guidance

required

normal

Age and OSI group

Figure 1. Result of osteo-sono assessment index (OSI).

ency of OSI groups and the frequency of present lifestyle habits and nutrition. An independent test showed sig-

M. Nakada et al. / HEALTH 2 (2010) 124-130

127

nificant differences in the amount of sleep in the

premenopausal group of females. However, the results of

residual analysis showed no significant differences in any

category. In postmenopausal females, there was no sig-

nificant difference in any present lifestyle habits or nu-

trition.

Table 4 (premenopausal females) and Table 5 (post-

menopausal females) show cross tabulations by the fre-

quency of OSI groups and past lifestyle habits and nutri-

tion (in junior high school and high school). An inde-

pendent test showed significant differences in the amount

of sleep and intake of vitamin D in the group of pre-

menopausal females. The results of residual analysis

showed significant differences in the intake of vitamin D,

and there was a higher proportion of subjects taking no

vitamin D in the close examination-guidance required

group (z＝2.77>2.64：p<0.05). In postmenopausal fe-

males, there was no significant difference in past lifestyle

habits and nutrition.

4. DISCUSSION

The Japan Osteoporosis Foundation [5] set the level for

close examination (OSI < 2.158) when using an AOS-100

device (ALOKA) as 0.8 - 1.0 % in people 40-year olds,

and 5.2 -11.4 % in 50-year olds. In this study, they were

respectively 1.3 % and 8.7 %. Hence, the level for close

examination was considered to be standard.

There were no differences in present lifestyle habits

and nutrition by OSI level. Nutrition and eating habits in

addition to exercise habits are important for maintaining

and increasing BMD. Principal minerals for absorption of

calcium are magnesium and Vitamin D [7]. We surveyed

past and present consumption of dairy products and vi-

tamin D excluding magnesium and present intake of

calcium supplements. Lloyd et al. [20] reported that by

increasing daily calcium intake from 80% of the recom-

mended daily allowance to 110% via supplementation

with calcium citrate malate resulted in significant in-

creases in total body and spinal bone density in adoles-

cent girls. The proportion of those test subjects taking no

vitamin D (fish, chicken egg, fungi etc) was higher in the

close examination-guidance required group than in the

normal group. The considerable amount of time that

elderly people spend indoors also decreases Vitamin D

synthesis through the skin in addition to their intake of

vitamin D [5]. Dawson-Hughes et al. [21] examined

during a long-term (3-year) study that the proper intake of

vitamin D with intake of calcium helps reduce the de-

crease of BMD. Intake of sufficient calcium and vitamin

D additionally promotes the absorption of calcium in the

small intestines, maintains calcitriol in the blood, and

prevents an increased parathyroid hormone (PTH) level.

This contributes to a reduction of bone loss [5,21]. The

absorption of calcium is supported by the intake of vita-

min D during puberty (junior high school and high school

age) which increases bone mass with skeletal growth

which may be very important for increasing peak bone

mass.

On the other hand, there was no difference in the past

or present lifestyle habits and nutrition in postmenopausal

females between the close examination and guidance

required groups and the normal group. Bone mass de-

creases with age at the rate of about 3 % a year through a

lack of estrogen even in normal postmenopausal females

[22]. Elderly people may need to increase their daily

requirement of calcium as their intestinal calcium ab-

sorption decreases [23]. Hence, with increasing age and

lack of estrogen, the bone metabolism of postmenopausal

females is largely affected, thus obscuring the effect of

past and present life habits on bone mass changes. In

addition, because of the long interval since puberty for

postmenopausal females, subsequent lifestyle habits

(eating habits and exercise) may have a greater affect on

BMD. Hence, a long-term study should be done consid-

ering the BMD of youth.

This study did not examine the effect of exercise

stimulus. Sanada et al. [24] reportedly showed a signifi-

cant relationship between calcaneal bone strength and the

strength of triceps muscle in postmenopausal females.

Bone mass increases by imposing the load of body mass

on the lumbar spine. Thus, the bone structure of the lower

limbs and thereby the bones of the upper and lower limbs

and spine benefit from the mechanical muscle stimulus

received from twisting, distortion, and towing. Therefore,

BMD is the result of past and present exercise and life-

style habits.

5. SUMMARY

This study examined the effect of past and present life-

style habits and nutrition on OSI in pre- and post-

menopausal females from 20 to 70 years of age.

1) The number of postmenopausal females in the close

examination and guidance required groups (80 cases:

51.3 %) (OSI < 2.428) was significantly higher than that

of premenopausal females (44 cases: 22.0 %) (χ2＝33.105:

P<0.000).

2) In premenopausal females, the number of subjects

who had not taken vitamin D in the past (in junior high

school and high school) was significantly higher in a

close examination-guidance required group (OSI < 2.428)

than in the normal group (OSI ≧ 2.428). However, in

postmenopausal females, there was no significant dif-

ference in past and present lifestyle habits and nutrition

between the two groups.

3) In premenopausal females, it was inferred that in-

creased intake of vitamin D during puberty is important to

increase the absorption of calcium.

M. Nakada et al. / HEALTH 2 (2010) 124-130

128

Table 3. Present lifestyle and nutrition habits and the OSI of postmenopausal females.

ypp

Sleeping timeLess than

6 hours

More than 6

hours - less

than 7 hours

More than 7

hours - less

than 8 hours

More than 8

hours

ｐφ

CEGR

22371741.330 0.722 0.09

Normal

17 38192

Alcohol intakeNo 1 - 3 times a

month

1 - 3 times a

week

nearly ever

CEGR

44168113.907 0.2720.16

Normal

43 8817

Smoking NoHave a habitQuit

CEGR

68741.028 0.5980.08

Normal

63 67

Skip a mealNoBreakfast LunchSupper

CEGR

713301.942 0.584 0.12

Normal

66311

Intake of dairy prodctsNo 1 - 3 times a

month

4 –

7 times a

week

CEGR

429451.001 0.606 0.08

Normal

22548

Intake of Ca supplementNoRarely Continuous

CEGR

5711102.349 0.309 0.12

Normal

60 511

Intake of vitamin DNo 1 - 3 times a

week

4 –

7 times a

week

CEGR

740320.012 0.9940.01

Normal

73830

Intake of instant foodNo 1 - 3 times a

month

More than

once a wee

CEGR

2124332.787 0.2480.14

Normal

27 2422

Sunbathing No 1 - 3 times a

week

More than 4

times a wee

CEGR

1231302.534 0.2820.13

Normal

10 2339

Result of OSI

Table 4. Past lifestyle and nutrition and the OSI of premenopausal females.

Sleeping timeLess than

6 hours

More than 6

hours - less

than 7 hours

More than 7

hours - less

than 8 hours

More than 8

hour s

ｐφ

CEGR

1(-1.96)10(-0.89)15(0.87)7(2.16)8.4710.037* 0.23

Normal

20(1.96) 48(0.89)46(-0.87) 10(-2.16)

Skip a mealNoBreakfast LunchSupper

CEGR

325001.225 0.2680.08

Normal

112 3100

Intake of dairy prodctsNo 1 - 3 times a

mon th

4 –

7 times a

week

CEGR

420141.825 0.4020.10

Normal

16 6172

Intake of vitamin DNo 1 - 3 times a

week

4 –

7 times a

week

CEGR

5(2.77*)22(0.17)8(-1.47)8.712 0.013*0.22

Normal

4(-2.77*) 87(-0.17)51(1.47)

Intake of instant foodNo 1 - 3 times a

mon th

More than

once a week

CEGR

71980.710 0.7010.06

Normal

24 7944

Note）

CEGR:close examination or

uidance re

uired

rou

*：P<0.05

Result of OSI

Number shown in parentheses is the Z score of the residual analysis

M. Nakada et al. / HEALTH 2 (2010) 124-130

129

yle and nutrition habits and the OSI of postmenopausal females. Table 5. Past lifest

ypp

Sleeping timeLess than

6 hours

More than 6

hours - less

than 7 hours

More than 7

hours - less

than 8 hours

More than 8

hours χ

ｐφ

CEGR 4242390.891 0.8280.09

Normal 6202510

Skip a mealNoBreakfast LunchSupper

CEGR 558202.527 0.2830.14

Normal 52 1100

Intake of dairy prodctsNo 1 - 3 times a

mo n th

4 –

7 times a

wee

CEGR 1539102.937 0.2300.15

Normal 13 3619

Intake of vitamin DNo 1 - 3 times a

mo n th

4 –

7 times a

wee

CEGR 740151.9460.3780.12

Normal 53823

Intake of instant foodNo 1 - 3 times a

mo n th

More than

once a wee

CEGR 2527100.203 0.9040.04

Normal 24 2912

Result of OSI

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291-300.