Basics
Description
Stuttering (also referred to as stammering or dysfluency) is an involuntary disturbance in the normal fluency and timing of speech that is not appropriate for the age of the speaker. Various patterns are seen:
- Prolongation of sounds or syllables
- Repetition of sounds, syllables, or even whole words
- Pauses in the middle of words
- Blocking " either silence or pauses filled with nonsense sounds in the middle of words as if considering what to say next
- Avoidance " word substitutions that are used to skip known problem words; also called circumlocution
- Overemphasis of some syllables or words; also called tension
- Stuttering is significant when it interferes with the patient 's life in academic, occupational, or social arenas. Many children with developmental delays have dysfluencies of speech, but it is not considered stuttering unless the dysfluencies are present more frequently than expected for the level of disability.
Epidemiology
- At least 1% of all studied populations affected
- Males stutter 3 times more often than females.
- Stuttering is found in every culture and language. The language spoken in the home does not increase or decrease the amount of stuttering.
- Stuttering begins between 2 and 7 years of age, with 98% of cases presenting by age 10 years.
- Girls start stuttering several months earlier on average than boys; however, they also speak, in general, earlier than boys do.
Risk Factors
Genetics
Stuttering does cluster in families:
- Monozygotic twins have a higher concordance for stuttering than dizygotic twins.
- The more closely related one is to a stutterer, the more likely one is to stutter.
- Identical twins have a concordance for stuttering of ≥30%.
- In specific families with a high propensity for stuttering, Lee et al. (and others) have shown single gene defects that correlate highly with dysfluency.
General Prevention
There is no known prevention strategy for stuttering.
Pathophysiology
Stuttering appears to be associated with an excessive amount of dopamine, or closely related vasoactive compounds, in the brain:
- Patients with Parkinson disease often develop adult-onset stuttering.
- PET scans show increased vasoactive substances in the brains of those who stutter.
- Medications that increase brain dopamine (antidepressants) or are dopaminergic (major tranquilizers) can induce stuttering in nonstutterers; medications that lower dopamine (e.g., clomipramine) may stop stuttering.
- Many differences exist between the brains of stutterers and nonstutterers in glucose uptake, dopamine release, and metabolic activity of the basal ganglia, but no single physiologic process has been well defined as the cause of stuttering.
Etiology
- Specific etiology is not known, but many factors contribute. Stuttering may be more pronounced when a child is fatigued, excited, upset, rushed, or exposed to some other stressor.
- Environmental factors are thought to have a role. Children adopted by a parent who stutters are more likely to stutter than children adopted by a parent who does not stutter.
Commonly Associated Conditions
- Other language problems: articulation disorders, phonologic disorders, learning disabilities, dyslexia, ADHD
- Students with developmental delay or intellectual impairment are found to stutter up to 25% of the time.
Diagnosis
History
- Stuttering runs in families by both nature and nurture.
- Age of onset and length of persistence
- Onset is insidious, with the child often unaware of the problem.
- If stuttering starts after the 10th birthday, suspect an intracranial mass or brain ischemia.
- Physiologic stuttering is rarely present during oral reading, singing, acting, and reciting in rhythm or while talking to pets or inanimate objects.
- Medications, especially those that increase dopamine, may activate stuttering.
- Increased intracranial pressure from disease or trauma may lead to stuttering.
Physical Exam
- There are no specific physical exam findings of stuttering. Observations of children improve the ability to make this diagnosis. Stuttering is 2 or more repetitions of a speech unit.
- Stutterers often improve in one-to-one situations with familiar people, so ask the parents to bring in a video recording of the child in a variety of situations: when talking in public, singing, and talking to a pet or infant.
- Observations that may be made in the office and correlate strongly with the diagnosis of stuttering include the following:
- Multiple repetitions and/or prolongations
- Rising pitch with difficult words
- Grimacing or other physical tension such as taking deep breaths or jerking the head back when speaking
- Inappropriate emphasis of words not normally emphasized, extremely slow speech, or speech without intonation
- Although unwillingness to speak to the examiner is normal, unwillingness to speak to the parent is not.
Diagnostic Tests & Interpretation
Diagnostic Procedures/Other
- None currently available, but PET scan may be a useful modality in the future
- If stuttering begins after the age of 10 years, or if the patient has additional neurologic or developmental problems, a workup for brain abnormalities should be considered.
Differential Diagnosis
- Developmental
- Normal development: dysfluencies associated with rapid onset of full speech capabilities that will usually resolve very quickly
- Transitory dysfluency is an ill-defined term but generally means stuttering in preschool-aged children that lasts <1 year.
- Cluttering: Patients with extremely rapid speech will have dysfluencies that resolve with slowing down of speech.
- Pervasive developmental disorder (autism spectrum disorder): may also have echolalia, tonelessness, and poor eye contact
- Neurologic
- Tics/Tourette syndrome: similar time of onset, initially somewhat similar symptoms. Stuttering is usually not associated with simultaneous physical movement.
- Trauma, tumor, or major CNS disease, such as Parkinson disease, may cause late-onset stuttering.
- Medications
- Any medication that increases the presence of dopamine may worsen (or cause) stuttering. Examples are SSRI-type antidepressants or major tranquilizers.
Treatment
General Measures
- Therapy must work on improving the child 's fluency and increasing acceptance and tolerance of this problem by the patient and his or her family.
- In a multicultural learning atmosphere, sensitivity to the learning styles of each social group is paramount in achieving successful results.
- Current evidence-based analysis suggests that early intervention by a certified speech pathologist is always indicated.
Additional Therapies
- Speech therapy
- Stuttering in young children can be resolved with very short courses of therapy, often ≤3 months. Stuttering remains resolved in ≥95% of these early treatment cases. The younger the patient is at the time of referral to speech therapy, the shorter the course of therapy needed, and the more likely that the therapy will be successful.
- Many experts in dysfluency believe that early intervention is more likely to be successful than waiting to start therapy if the stuttering has not spontaneously resolved by the 7th birthday.
- Among the more successful new programs for young children who stutter is the Lidcombe Program of Early Stuttering Intervention, an intense behavioral therapy program that centers on the belief that stuttering is physical in nature. The program teaches parents and caregivers to praise the child for speaking fluently and to correct them occasionally when they stutter. Parents are supported throughout the process by the clinician. The therapy ultimately enables the child to speak fluently and to monitor his or her own speech.
- Other therapies
- A successful new therapy for adolescents and adults is a hearing-aid type device (SpeechEasy, www.speecheasy.com) that feeds the individual 's speech directly back into an earpiece.
- Devices that make hearing monaural or provide a white noise background in the ear also improve stuttering.
- Information for families is available through organizations such as The Stuttering Foundation, a nonprofit organization (www.stutteringhelp.org).
Alert
- Because stuttering waxes and wanes with time, temporary improvement does not equal cure.
- Any behavioral therapy must be done under the guidance of a well-trained professional because inappropriate criticism may worsen stuttering.
- Waiting to see if stuttering goes away by age 7 years is not the best strategy for young children, as was often taught in the past.
- The literature does not give a clear time frame for how long stuttering in preschool children should last before requiring evaluation and treatment, but a significant stutter that lasts for >1 year should be referred to a speech therapist.
- No medications are known to reduce stuttering safely. Acupuncture, hypnosis, and yoga have been used with some success but not in controlled studies.
Ongoing Care
Follow-up Recommendations
If stuttering is reported by the parents in a preschool-aged child, follow up in 1 " 2 months to see if it was only a transitory dysfluency that has resolved. If not, obtain a speech therapy consult for evaluation.
Patient Monitoring
- Periodic follow-up to ensure that speech therapy is in place and that progress is being made
- Reassessment to ensure that child is adapting to social situations and interacting with others
Patient Education
- The following suggestions, although helpful to parents, should be recommended in conjunction with, but not in place of, speech therapy. Parents may be too critical of their own children.
- Take time out of each day to speak with the child one-on-one.
- Model slow speech.
- Wait for the child to speak. Take turns speaking.
- Allow for transition time between activities and tasks.
- Keep a notebook of things that help make speech better and things that elicit stuttering.
Prognosis
- Up to 80% of stuttering cases spontaneously regress by age 16 years.
- Severity of stuttering does not relate to persistence of stuttering.
- The longer stuttering exists, the more likely it will persist.
Complications
- Anxiety and depression, often far out of proportion to the degree of dysfluency
- Blocking and hesitation, giving an impression of delayed intellectual development
- Voluntary withdrawal from social interaction to avoid embarrassment
Additional Reading
- Craig A, Hancock K, Tran Y, et al. Epidemiology of stuttering in the community across the entire life span. J Speech Lang Hear Res. 2002;45(6):1097 " 1105. [View Abstract]
- Jones M, Onslow M, Packman A, et al. Randomised controlled trial of the Lidcombe programme of early stuttering intervention. BMJ. 2005;331(7518):659 " 661. [View Abstract]
- Lee W, Kang C, Drayna D, et al. Analysis of mannose 6-phosphate uncovering enzyme mutations associated with persistent stuttering. J Biol Chem. 2011;286(46):39786 " 39793. [View Abstract]
- Onslow M, O 'Brian S. Management of childhood stuttering. J Paediatr Child Health. 2013;49(2):E112 " E115. [View Abstract]
- Rosenfield DB, Viswanath NS. Neuroscience of stuttering. Science. 2002;295(5557):973 " 974. [View Abstract]
- The Stuttering Foundation. Videotape No. 70: Stuttering and the preschool child. Help for families. Memphis, TN: Stuttering Foundation of America; 2000. http://www.stutteringhelp.org.
- van Beijsterveldt CE, Felsenfeld S, Boomsma DI. Bivariate genetic analyses of stuttering and nonfluency in a large sample of 5-year-old twins. J Speech Lang Hear Res. 2010;53(3):609 " 619. [View Abstract]
- Ward D. The aetiology and treatment of developmental stammering in childhood. Arch Dis Child. 2008;93(1):68 " 71. [View Abstract]
- Yairi E, Ambrose N. Epidemiology of stuttering: 21st century advances. J Fluency Disord. 2013;38(2):66 " 87.
Codes
ICD09
- 315.35 Childhood onset fluency disorder
ICD10
- F80.81 Childhood onset fluency disorder
SNOMED
- 141441000119107 childhood onset stuttering (finding)
FAQ
- Q: Are some children more prone to stuttering?
- A: Yes. "Sensitive " children (many different definitions in many different studies) are more likely to stutter as are the children of highly critical parents.
- Q: Should family and friends complete the sentences of children who stutter?
- A: No. Children who cannot complete a thought should be gently asked to slow down and try again with no time limit set; others should simply wait until the child has completed his or her sentence. Children with a stuttering problem should also be praised when they do not stutter.