Health state utilities of patients with periodontitis

1. Tuti Ningseh Mohd-Dom1 BDS (Malaya), MPH (Michigan), PhD (UKMalaysia)
Co-authors: Sharifah Ezat Wan Puteh2, Rasidah Ayob3, Syed Mohamed Aljunid2
1Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia,
2Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia,
3Oral Health Division, Ministry of Health, Malaysia, Putra Jaya, Malaysia

2. An individual’s levels of functioning within a set
of health domains such as mobility, cognition,
pain, emotional functioning, self-care etc.
Valued as utilities, which is a measure of one’s
goodness of life
Perfect health = 1.0, dead = 0.0

3. A standardised non-disease-specific instrument
for describing and valuing health-related quality
of life (Brooks 1996)
Purposefully developed to generate a generic
index of health that places health states on
scale from zero (worst health) to one (best
health)

4. The EQ-5D-3L essentially consists of 2
components
(1) the EQ-5D descriptive system and the
(2) EQ visual analogue scale (EQ VAS)
The EQ-5D-3L descriptive system comprises the
following 5 dimensions: mobility, self-care,
usual activities, pain/discomfort and
anxiety/depression.
Each dimension has 3 levels: no problems, some
problems, extreme problems.

5. 




• An EQ-5D health state (or profile) is a set
of observations about a person defined
by the descriptive system
• There are 243 possible health states
• This example identifies the state 11123
• An EQ-5D health state may be converted
to a single summary index (utilities)

6. The Visual Analogue Scale

7. As an outcome measure, uses of
values (utilities) include:
1. Societal resource allocation: priority setting
across proposed programs or interventions
2. Societal (programmatic) audit: evaluation of
ongoing activities/programs
3. Personal clinical decisions
Main advantage: to compare outcomes or values
of disparate healthcare programmes or
interventions

8. Is an outcome measure that takes into account
both the quantity and the quality of the extra
life provided by a health care intervention
It is the health state utility value (quality)
multiplied by life expectancy of a person
(quantity)
It provides a common currency to assess the
extent of particular benefits gained from a
variety of interventions in terms of health
related quality of life and survival for the patient

9. 1. A tooth that has been diseased and has
undergone treatment will be able to function
and survive for a number of years (quantity)
2. But patient may experience some side effects
such as tooth hypersensitivity or impaired
aesthetics (quality)
3. The concept of QATYs is introduced to measure
the status of teeth that have undergone
treatment (it may not be able to function as a
perfectly healthy tooth) Birch 1986, Antzak-
Bouckams 1987.

10. Is an outcome measure which is a dental
analogous of QALY. It is a measure of quality of
tooth in relation to its tooth life expectancy,
rather than quality of life of the individual.
Value scale:
Perfect health = 1.0,
Tooth extracted = 0.0

11. Aim:
To assess the effectiveness of periodontal treatment provided at selected
government specialist dental clinics using patient-reported outcomes.
Specific objectives:
1. To determine the oral health-related quality of life of patients newly-
diagnosed with periodontitis
2. To determine the health state utilities of patients newly-diagnosed with
periodontitis
3. To contrast the oral health-related quality of life and health state utilities of
newly-diagnosed periodontitis patients with that after completing cause-
related periodontal treatment
This study was a part of a larger study investigating
cost-effectiveness of periodontal therapy

12. METHODS

13. Newly-diagnosed
periodontitis
Patient-reported
outcomes
(12-months
follow-up)
Clinical parameters
Cost analysis
Patient recruitment
All periodontic clinics in the
Ministry of Health
Five clinics in Peninsula
Malaysia randomly sampled
Periodontal
therapy
COST EFFECTIVENESS ANALYSIS
STUDY FLOW

14. New adult patients attending periodontics clinic
for management of chronic/ aggressive
periodontitis (has a Basic Periodontal
Examination code 3 or 4 in at least one sextant
on clinical examination)
Patients who have not had any extensive
periodontal treatment (including sub-gingival
scaling) within six months prior

15. (2) Presence /
Missing teeth
(6) Periodontal pocket depth
(4) Gingival
recession
(5) Clinical attachment level
(1) Bleeding on probing
(degree of inflammation)
(3) Degree of
Tooth mobility

16. Slade&Spencer,1994,Saubetal2005,2007
(1) Functional limitation
• Difficulty in chewing
• Bad breath
(2) Physical pain
• Ulcers
• Uncomfortable to eat
(4) Physical
disability
• Avoid certain food
• Avoid smiling
(3) Psychological
discomfort
• Food stuck
• Felt shy
(5) Disturbed
concentration
• Been embarrassed
(6) Social disability
• Avoid going out
• Daily activities
(7) Handicap
• Spent a lot of money
• Felt less confident

17. (3) EQ-5D-3L Euro-QoL; Brooks1996
(a) Descriptive system: Have your dental conditions
caused you problems in (1 no/ 2 some/ 3 extreme):
(b) Visual Analogue Scale (0-100)
Mobility Self care
Usual
activities
Pain,
discomfort
Anxiety,
depression
EQ-5D-3L has been validated in Malay language to be used among
Singaporeans (Wee et al 2007) as well as Malaysians (Shafie et al 2011)

18. n=[ 2 (s2) / d2] (zα + zβ)2
zα = 1.96 because α is set at 0.05, zβ = 0.84 because β is set at
0.20 (power 80%)
s = 10.76 (standard deviation of OHIP score of periodontitis
patients before treatment , Ng et al 2006)
d = 5 (minimal important difference, derived from mean change
OHIP scores divided by standard deviation of change scores,
Locker et al 2004)
Hence, n = [2 (10.76)2 / (5)2 ] (1.96+0.84)2 = 73 patients
Giving allowance for loss to follow up of q=55 -60% (Locker et al 2004,
Bajwa et al 2007), estimated total sample size= 73/(1-q)= 73/0.40 =
182.5  185

20. Background of sample cohort
• Total sample was 165 patients, about 20% loss to follow-up
• There were more women than men. About half studied at least up to
secondary school and the rest had tertiary education. Their mean age was
43.3 (S.D 11.3) years old.
• Only about one-third worked as professionals, while the others either had
non-professional occupations or were unemployed. Majority were Malay
and earned at least up to the average capita Gross Domestic Product
(GDP).
• Chronic periodontitis patients outnumbered aggressive periodontitis cases
by a four-fold.
• For chronic periodontitis patients, most exhibited moderate periodontitis,
followed by severe while very few were mild.
• All cases of aggressive periodontitis are considered severe.

21. Indicators Pre-
treatment
Post-
treatment
Test
statistic
P-value 95%
confidence
interval
Prevalence: % of
people reporting
1+ impacts
fairly/very often
130 (78.8) 52 (31.5) - *< 0.0001 -
Extent: mean
number of items
reported fairly/
very often (S.D)
3.3 (3.2) 1.3 (2.1) 8.2 # < 0.0001 1.5, 2.5
Severity: mean S-
OHIP14 score
(S.D)
20.3 (10.5) 12.7 (10.7) 10.8 # < 0.0001 8.1, 11.8
Results (1) Prevalence, severity and extent scores of oral health impacts
(OHIP-14), pre- versus post-treatment
Intention-to-treat analysis, level of significance α = 0.05, * Mc Nemar test, # Paired t-test

22. Results (2) Mapping of EQ-5D health states with utility values

23. EQ-5D-3L health states Pre-treatment
(n, %)
Post-treatment
(n, %)
P-value
Perfectly healthy 67 (40.6) 115 (69.7) *<0.001
Less than healthy (Other
states)
98 (59.4) 50 (30.3)
Level of significance α = 0.05, * Mc Nemar test
Results (3): EQ-5D-3L health states, pre- versus post-
treatment

24. Results (4): Improvement in EQ-5D descriptive items, pre- vs. post-
treatment
Intention-to-treat analysis, level of significance α = 0.05, *Mc Nemar test

25. I. Quality-adjusted life year (QALY), pre- vs. post-treatment
Results (5): QALY and QATY, pre- vs. post-treatment
II. Quality-adjusted tooth year (QATY), pre- vs.. post-treatment
Items Pre-treatment
Mean (S.D)
Post-treatment
Mean (S.D)
Gain in QALY
Mean (S.D)
EQ5D utilities 0.81 (0.19) 0.91 (0.14) -
Life expectancy 35.76 (10.9) 35.76 (10.9) -
QALY* 28.92 (11.3) 32.72 (11.6) 3.8 (8.0)+
Level of significance α = 0.05, *Paired t-test, P<0.001
+Median gain in QALY=0.00, IQR=10.1, Wilcoxon Signed Rank Test, P<0.001
Items Mean (S.D.)
Pre-treatment Post-treatment Gain in QATY
OHIP-utilities 0.61 (0.2) 0.79 (0.2) -
Tooth life expectancy 4.5 (0.0) 24.9 (11.4) -
QATY* 2.73 (0.8) 19.9 (10.7) 17.1 (10.8)
Level of significance α = 0.05, *Paired t-test, P<0.001

26. Periodontal parameters Pre-treatment
Post-
treatment
P-value, paired
t-test
No of teeth (mean and SD) 26.5 (3.9) 25.( (4.2) <0.0001
Full mouth plaque scores (FMPS; %) 56.2 (26.6) 39.4 (29.1) <0.0001
Full mouth bleeding scores (FMBS;
%)
47.9 (28.3) 29.9 (27.9) <0.0001
Sites with PPD ≥ 4 mm (%) 32.7 (20.6) 23.2 (20.2) <0.0001
Probing pocket depth (PPD) (mm;
mean and SD)
3.2 (0.9) 2.7 (0.9) <0.0001
Gingival recession (REC) (mm; mean
and SD)
0.8 (0.8) 0.9 (0.9) <0.0001
Clinical attachment level (CAL) (mm;
mean and SD) 4.0 (1.3) 3.7 (1.3) <0.0001
Results (6): Clinical parameters, pre- vs. post-treatment

27. The use of health state utilities as a measure of
periodontal treatment outcome demonstrated
effectiveness of treatment, consistent with
improvements in clinical measures.
Its use should be considered in economic
evaluation of dental treatments.

28. 8/25/2015 28
Acknowledgements
Ministry of Health Malaysia
Ministry of Higher Education
Faculty of Dentistry, UKM
Faculty of Medicine, UKM
United Nations University-IIGH
tutinin@ukm.edu.my Q&A
Study received funding from the UKM Medical Faculty
(Fundamental FF-232--2010) and Ministry of Higher
Learning (ERGS/1/2011/SKK/UKM/02/73).