Association Between Active Life Expectancy and Dental Conditions

Yasuhiko SaitoNihon University, Tokyo, Japan

Second Mexico-Japan Meeting on Health Ageing

June 20-21, Mexico City, Mexico

Introduction

• Having fewer teeth or decreased chewing ability leads to an increased risk of mortality independent of other factors including socioeconomic status, life style and health factors (Ansai et al. 2007; Hamalainen et al. 2003; Osterberg et al. 2008;

Padhila et al. 2008; Shimazaki et al. 2001; Yoshida et al. 2005)

• The link between chewing ability, nutritional status and an increased risk of mortality among the elderly (Nakanishi et al. 2004; Walls and Steele 2004)

Introduction

• Oral health is

– related to the risk of disability among the elderly (Holm-Pedersen et al. 2008; Takata et al. 2004; Takata et al. 2008)

– related to the higher incidence of disability (Shimazaki et al. 2001; Holm-Pedersen et al. 2008)

– a signpost and a symptom of declining overall health and may put elderly at risk for transitioning from a healthy state (Locker 2002; Locker et al. 2002; Nasu

and Saito 2006)

Motivatoin

• Previous studies have investigated the association between oral health, disability and mortality.

• There is, however, little research exploring the association between oral health and active life expectancy.

• Studied Japanese older adults 65+ and Singaporean older adults 60+

Measure of Ability to Chew

Question: The following foods are ordered from hardest to softest to chew. What is the hardest group you are able to bite and chew? If you are using dentures, please respond as if you were eating with your dentures.

4 Possible Outcomes

• Ability to Chew (Y) and Number of teeth (Y)

• Ability to Chew (Y) and Number of teeth (N)

• Ability to Chew (N) and Number of teeth (N)

• Ability to Chew (N) and Number of teeth (Y)

List of Foods for Japan1. Saki ika or takuan (Hard dried squid or

pickled radish)

2. Boiled pork meat (from the rump), raw carrots, or celery

3. Deep-fried tofu, pickled octopus, pickled Chinese cabbage, or raisins

4. Rice, apples, fish cake, or boiled asparagus

5. Bananas, boiled beans, canned corned beef, or wafers

6. Unable to chew the foods listed

Group A

Group B

List of Foods for Singapore1. Ikan Bilis in Nasi Lemak or shredded dry

squid

2. Mutton curry, dry mango, or fresh carrots

3. Bak-kwa, bread with crust not toasted, or kang kong steam boiled, chicken satay, or raw cucumber

4. Thai Rice, fried fish ball, or Wanton noodle

5. Bananas, ripe papaya, hard boiled egg

6. Unable to chew the foods listed

Group A

Group B

Number of Teeth

Question : How many original teeth do you (subject) have? Adults have 28 natural adult teeth (32 including wisdom teeth) and 0 for full dentures. Prosthetic teeth with roots should be included in the number. For bridges, the artificial tooth should not be counted; however, natural teeth acting as supports should be.

20 or more VS 19 or less

Data

• Nihon University Japanese Longitudinal Study of Aging (NUJLSOA)

• Conducted in 1999, 2001, 2003

• Nationally representative sample of age 65 and over in 1999

• Sample Size for this study

– Males: about 1800 Females: about 2400

Definition of Health

• Inactive: unable or very difficult to perform, at least, one of 7ADLs or 7 IADLs

• Active: otherwise

– 7 ADL: bathing, dressing, eating, getting in/out of bed, walking, going outside, toileting

– 7 IADL: preparing for own meal, shopping, managing money, making phone, doing light house work, using public transportation, medication

Methods

• Compute Active Life Expectancy using Multistate Life Table Method

– Population-based and Status-based

• by Ability to chew (Groups A and B)

• by Number of teeth (20+ VS 19-)

• IMaCh was used to compute ALE

LE by Ability to ChewPopulation-based: Both Sex

Group A Group B Statistical

TestLE SE LE SE

65 21.6 0.49 19.4 0.59 *

70 17.6 0.47 15.7 0.50 ns

75 13.9 0.48 12.3 0.46 ns

80 10.5 0.48 9.2 0.44 ns

85 7.5 0.49 6.7 0.44 ns

ALE by Ability to ChewPopulation-based: Both Sex

Group A Group B Statistical

TestALE SE ALE SE

65 18.0 0.36 15.2 0.46 **

70 14.0 0.33 11.4 0.38 **

75 10.2 0.32 8.0 0.33 **

80 6.9 0.31 5.0 0.28 *

85 4.1 0.30 2.7 0.24 *

LE by Number of TeethPopulation-based: Both Sex

20 or more 19 or less Statistical

TestLE SE LE SE

65 23.0 0.98 20.2 0.42 *

70 18.9 0.97 16.4 0.36 ns

75 14.9 0.96 13.0 0.36 ns

80 11.3 0.94 9.8 0.36 ns

85 8.1 0.88 7.1 0.39 ns

ALE by Number of TeethPopulation-based: Both Sex

20 or more 19 or less Statistical

TestALE SE ALE SE

65 19.6 0.72 16.3 0.33 **

70 15.5 0.70 12.5 0.27 **

75 11.5 0.67 8.9 0.24 **

80 8.0 0.63 5.8 0.23 *

85 5.0 0.56 3.5 0.22 *

Answer to the Question

BOTH Matter!!

for ALE based on the grouping

we used

Data

• A nationally representative longitudinal (2 waves; 2009 and 2011-12) survey in Singapore

– N=4990 at baseline

– aged 60+

– Analysis samples

• number of teeth: N=3,318

• chewing ability: N=3,356

Measures

• Death– linked to the national Registry of Births and Deaths

databases

– follow-up

• Disability– 6 ADLs

• bath, dress, eat, bed, chair, walk, toilet

– 7 IADLs• meals, shop, financial, phone, light housework, public

transport, take medication

Method

• Incidence-based multistate life tables (MSLTs) were constructed by IMaCh

Active Inactive

Dead

Health transitions

Health Status: n(%)

Wave 2

Dental Status Wave 1 Active Disabled Dead Sum

Number of Teeth Active 2,242 (75.9) 337 (7.6) 142 (3.4)

Disabled 121 (3.2) 342 (7.1) 134 (2.7)3,318

(100.0)

Chewing Ability Active 2,263 (75.7) 340 (7.6) 143 (3.4)

Disabled 122 (3.2) 352 (7.3) 136 (2.7)3,356

(100.0)

Note: sample sizes (n) are unweighted, but proportions (%) are weighted.

Population-based at age 60 : # of teeth

Both gender

0-19 20+

Est. 95% CI % Est. 95% CI %

TLE 23.1 (21.7, 24.5) 100.0 26.6 (22.5, 30.6) 100.0

ALE 17.8 (16.8, 18.7)* 76.8 20.9 (18.9, 23.0) 78.8

IALE 5.4 (4.5, 6.3) 23.2 5.6 (2.7, 8.6) 21.2

Men

0-19 20+

Est. 95% CI % Est. 95% CI %

TLE 21.0 (19.3, 22.7) 100.0 24.1 (20.9, 27.3) 100.0

ALE 18.3 (16.9, 19.7) 87.2 21.2 (18.9, 23.5) 87.9

IALE 2.7 (1.9, 3.5) 12.8 2.9 (1.3, 4.5) 12.1

Women

0-19 20+

Est. 95% CI % Est. 95% CI %

TLE 25.0 (23.0, 26.9) 100.0 29.1 (23.7, 34.5) 100.0

ALE 17.3 (16.2, 18.5) 69.4 20.6 (18.3, 22.8) 70.6

IALE 7.7 (6.2, 9.1) 30.6 8.6 (4.2, 12.9) 29.4

* p < 0.05

Population-based at age 60 : chewing ability

* p < 0.05

Both gender

Unable Able

Est. 95% CI % Est. 95% CI %

TLE 20.3 (18.2, 22.3)* 100.0 26.0 (23.8, 28.3) 100.0

ALE 14.9 (13.3, 16.4)* 73.3 20.1 (19.0, 21.3) 77.3

IALE 5.4 (4.2, 6.6) 26.7 5.9 (4.3, 7.6) 22.7

Men

Unable Able

Est. 95% CI % Est. 95% CI %

TLE 18.6 (16.4, 20.9)* 100.0 23.2 (21.1, 25.2) 100.0

ALE 15.8 (13.9, 17.7)* 84.7 20.3 (18.7, 21.8) 87.5

IALE 2.9 (1.9, 3.8) 15.3 2.9 (1.8, 3.9) 12.5

Women

Unable Able

Est. 95% CI % Est. 95% CI %

TLE 21.7 (19.3, 24.1)* 100.0 28.7 (25.5, 31.9) 100.0

ALE 14.1 (12.3, 15.8)* 64.8 19.9 (18.5, 21.4) 69.5

IALE 7.6 (5.9, 9.3) 35.2 8.8 (6.3, 11.3) 30.5

Status-based at age 60: chewing ability

Both gender

Unable Able

Initial State Est. 95% CI % Est. 95% CI %

Active

TLE 20.5 (18.5, 22.4)* 100.0 26.1 (23.8, 28.3) 100.0

ALE 15.1 (13.7, 16.6)* 74.0 20.2 (19.1, 21.4) 77.5

IALE 5.3 (4.2, 6.5) 26.0 5.9 (4.2, 7.5) 22.5

Inactive

TLE 16.5 (13.2, 19.8)* 100.0 24.3 (21.7, 26.9) 100.0

ALE 9.2 (6.6, 11.9)* 56.0 16.4 (14.5, 18.2) 67.4

IALE 7.3 (5.6, 9.0) 44.0 7.9 (6.2, 9.6) 32.6

* p < 0.05

Status-based at age 60: chewing ability

Men

Unable Able

Initial State Est. 95% CI % Est. 95% CI %

Active

TLE 18.8 (16.5, 21.0)* 100.0 23.2 (21.1, 25.2) 100.0

ALE 16.0 (14.1, 17.8)* 85.1 20.3 (18.8, 21.8) 87.6

IALE 2.8 (1.9, 3.7) 14.9 2.9 (1.8, 3.9) 12.4

Inactive

TLE 13.6 (9.7, 17.4)* 100.0 20.6 (17.6, 23.6) 100.0

ALE 8.6 (5.3, 11.9)* 63.4 15.6 (12.8, 18.3) 75.6

IALE 5.0 (3.4, 6.6) 36.6 5.0 (3.7, 6.4) 24.4

* p < 0.05

Status-based at age 60: chewing ability

Women

Unable Able

Initial State Est. 95% CI % Est. 95% CI %

Active

TLE 22.0 (19.6, 24.3)* 100.0 28.8 (25.6, 32.0) 100.0

ALE 14.4 (12.9, 16.0)* 65.8 20.1 (18.6, 21.5) 69.7

IALE 7.5 (12.9, 16.0) 34.2 8.7 (6.2, 11.2) 30.3

Inactive

TLE 18.7 (15.0, 22.4)* 100.0 27.2 (23.8, 30.7) 100.0

ALE 9.4 (6.7, 12.1)* 50.2 16.6 (14.6, 18.6) 61.0

IALE 9.3 (7.1, 11.6) 49.8 10.6 (8.1, 13.2) 39.0

* p < 0.05

Summary

• Number of teeth

– Significant association with ALE

– But not TLE

• Sample size

• # of teeth may not be associated with ADL (Akifusa et al. 2005)

• Chewing ability

– Significant association with ALE and TLE

Limitation/Further consideration

• Sample size may not be large enough

• Other factors to be considered

• Number of teeth: not functioning teeth

• Measure of chewing ability