Download Effects of RMST on Speech Intelligibility in PD

Effects of Specific Respiratory Muscle Training on Speech Intelligibility of a Patient with Parkinson’s Disease
Vaneysa Hansen, MA, SLP (C) & Barbara Mathers-Schmidt, PhD, CCC-SLP
Western Washington University, Bellingham, WA
90.00%
85.00%
80.00%
Judge 1
75.00%
70.00%
65.00%
Percentage of Intelligible
words
95.00%
0.95
Intelligibility
0.9
Percentage of Intelligible Speech on the SIT (Figure 1)
Results- improved subject performance
Judge 1
increase of 6.88% - baseline  5th week of training
increase of 15.22% - end of withdrawal  19th week of training
0.85
Participant
52-year-old male with advanced PD (onset 1990)
Medications: Sinemet: L-dopa/ Carbidopa; Comtan and Welbutrin
 Bilateral pallidotomy in 1997
Neuromotor assessment revealed:
 Rigidity in the muscles of the face and mandible.
 Hypokinetic dysarthria and palalalia in conversation
 Ability to sustain a steady respiratory driving pressure of 5 cm of H2O for 5 sec and 10 cm of
H2O for 10 seconds before each training phase
 Speech had improved 3 months prior to study due to more effective doses of Sinemet.
Study Design
•ABAB within-subject withdrawal design in 4 phases over 19 weeks:
A1 = (week 1) baseline testing
B1 = (weeks 2-6) first respiratory training phase
A2 = (weeks 7-10) withdrawal phase
B2 = (weeks 11-19) second respiratory training phase
Baseline data
Maximum
Inspiratory Pressure (MIP) & Maximum Expiratory Pressure (MEP)
Sentence Intelligibility Test scores (SIT; percent intelligible, speaking rate, and
communication efficiency ratio),
Forced Vital Capacity (FVC) and percent predicted (FVC%)
Intensity levels (dB)
Communication surveys completed by subject and his wife
A2
A2
B2
B2
B2
B2
A2
A2
B1
B1
B1
A1
Speaking rate and intelligibility rate
Results- general increased rate (characteristic of hypokinetic dysarthria)
Communication coefficient
Slight increase during training, no significant change
Single words (Figure 2)
Results- improved subject performance by 4%
Unpredictable Sentences
Results- improved subject performance by 8.59%
0.8
B2
B2
B2
Training Phase
Training Phases
Figure 3: Forced Vital Capacity (FVC)
Figure 4: The Percent Predicted -Forced Vital Capacity
B2
B2
50%
40%
30%
20%
Outcome Measures
Measurements
were completed twice during baseline testing,
and again at the end of week 4, beginning of week 5 and end
of week 6 in the 1st training phase (B1).
& Parle’s Unpredictable Sentences and Kent
Phonetic Contrast Word List were added to the outcome
measures in A2 and B2. All measurements were completed
twice during baseline testing/end of withdrawal period, and
again at the end of week 14, beginning of week 15 and twice in
the middle of week 19.
McHenry
The
Communicative Effectiveness Survey (Sullivan et al.,
1997) and The Rating Scale for Speech Characteristics in
Parkinson’s disease (Ramig, 1992) were completed by the
subject and his wife before the 1st treatment phase and at end
of each treatment phase.
Reliability
3
judges for intelligibility data
2 SLP grad students (Judge 1 & 2), 1 political science
undergrad student (Judge 3-naïve judge)
Protocols provided to all judges
Interjudge reliability:
All judges were within 5% for all but the 1st baseline (A1baseline 1)
Judge 3 was within 15% of the more experienced judges,
with more than ½ of scores within 5%.
Intrajudge reliability:
Judge 1 was within 5% for all but 1 score (A1-baseline 2).
FVC (Figure 3)
Results- by 1.5 L (from 3.04-4.54 L).
Predicted FVC% (Figure 4)
Results- Increased with respiratory training by 29.15% (from 58%-87.10%)
B2
B2
FVC%
B2
A2
60%
B2
A2
Spirometry measures
A2
B1
70%
A2
A1
80%
B1
A1
No significant change in MIP/ MEP following the no treatment period.
90%
A1
FEV
Respiratory Muscle Strength:
100%
A1
FCV (Liters)
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
FCV% Predicted percentage
(FVC%)
Training phases
METHOD
RESULTS
1
60.00%
Combining inspiratory and expiratory training could resynchronize the ventilatory
system, by improving lung volume and decreasing the workload of the expiratory
muscles, thereby increasing respiratory driving pressures to benefit speech sound
generation and control.
The purpose of this time-series design study was to determine if
specific respiratory muscle training would result in increased
speech intelligibility and improvement in measures of vocal
intensity, maximal inspiratory and expiratory pressures, lung
volume and self-rating of communication success in a patient with
PD.
Figure 2: Speech Intelligibility Scores for Single Words on the Kent Phonetic Contrast Test
100.00%
A1
Previous research has acknowledged that respiratory dysfunction is a common result
of PD and may be due to muscle weakness or reduced compliance of the rib cage
due to muscle rigidity (Yorkston et al., 2003 & Silverman et al., 2006). The rigidity
contributes to reduced lung volumes and respiratory pressures. Strengthening the
expiratory muscles may increase the patient’s ability to surmount rigidity, thereby
increasing respiratory driving pressure for speech and enhancing vocal intensity,
vocal quality, duration, and speech sound quality(Draper, Ladefoged, Whitteridge,
1959; Finnegan, Luschei, Hoffman, 2000; Isshiki, 1964). Similarly, strengthening
inhalatory muscles would result in increased lung volumes for speech. In addition,
increased diaphragm activity influences the posterior cricothyroid muscle activation
which likely affects sound generation and voice quality (Ruddy et al., 2004).
Figure 1: Percentages of intelligible speech on the SIT
Percentage of Intelligible Speech
At least seventy-five percent of people with Parkinson’s disease (PD) have related
voice and speech abnormalities often collectively labelled as hypokinetic dysarthria
(Sapir et al., 2002). Severity of the dysarthria ranges from mild to severe. The
objectives of intervention typically include improving speech intelligibility and
communication effectiveness.
Training phases
Inspiratory & Expiratory Muscle Training (EMT/IMT)
Communicative Effectiveness
Survey & Rating Scale
Overall, results indicated no awareness of improved speech noted by the subject and
some awareness of improved communicative effectiveness noted by his wife.
Prior to EMT/IMT, participant was educated re: mechanics
of respiration
Power
Lung -a spring-loaded resistance training
device
Inhalation control dial (1 ->6)
Exhalation control dial (1->3)
Place mouth over the lip shield and breathe in and
out.
Settings on dials adjust level of effort needed to open
valve inside
Participant trained 5 days per week for 5 weeks
2 sets of 10 reps twice daily (1 set in morning, 1 set in
afternoon/evening).
1 set = 10 reps inhalation & 10 reps exhalation with
secured nose clip
1st 8 reps, breathe in/out for 3 seconds
9th and 10th repetitions, breathe in/out in 1 second
One
minute rest period between sets. Each session
approximately 30 minutes.
Increase
settings on PowerLung to 1/8 of a turn when
reps become less effortful (i.e. no longer using ideal
setting).
Weekly or biweekly phone calls or emails were used
to ensure compliance with training protocol and to
answer questions
1 time per week, trained with researcher in Clinic.
To
adjust settings and maintain subject’s ideal settings as
strength increased.
To
provide feedback on technique.
DISCUSSION AND CONCLUSIONS
Speech intelligibility improved in response to EMT/IMT training
Changes in FVC and FVC% indicate increased lung capacity and increased control of that
power supply for speech
Increased lung volume is associated with increased range of motion of respiratory muscles
= greater expansion of the rib cage.
IMT/EMT may have decreased rigidity and increased range of motion as shown by
increased vital capacity.
Increased control over airway due to increase in muscle strength may have resulted in
increased intelligibility.
Diaphragm and PCA connection may result in transfer of strength and coordination of
speech respiration.
Measures of MEP, MIP, communication efficiency, and intensity did not indicate
improvement in the anticipated direction. This may be associated with limitations in
measurement tools and procedures.
Respiratory training may have improved speech intelligibility and lung volume in an
individual with PD because increased ventilatory control and lung volume give patient more
time to achieve articulation targets.
Conclusion: EMT/IMT may be a promising treatment approach for improving speech
intelligibility in patients with Parkinson’s disease.
References and handouts available by email: [email protected] &
[email protected]