What are the possible causes of new‑onset stuttering in a 62‑year‑old woman?

New-Onset Stuttering in a 62-Year-Old Woman: Differential Diagnosis

New-onset stuttering in a 62-year-old woman requires urgent evaluation for stroke, followed by systematic consideration of functional neurological disorder, other neurogenic causes, and medication effects.

Critical First Step: Rule Out Stroke

The most important immediate consideration is acute ischemic stroke, as stuttering can be the sole presenting manifestation of cerebrovascular events 1. A 62-year-old patient presenting with episodic or persistent new-onset stuttering requires:

• Immediate brain imaging (MRI preferred, CT if MRI unavailable)
• Focus on cortical regions involved in speech motor control, particularly:
  • Left hemisphere cortical areas (more common in stroke-related stuttering)
  • Precuneus cortex
  • Frontal/parietal regions
  • Basal ganglia and subcortical structures

The pathophysiology involves disruption of the cortico-striato-cortical integrative pathway mediating speech execution, which can occur at any level 1.

Functional Neurological Disorder (Most Common Non-Stroke Cause)

If neuroimaging is negative, functional stuttering becomes the leading diagnosis 2. This diagnosis is supported by:

Distinguishing Features:

• New onset in adulthood without prior developmental speech difficulties
• Unusual consistency patterns: stuttering on every syllable, every word, or first word of every sentence
• Paradoxical worsening with simple speech tasks
• Lack of improvement with activities that typically promote fluency
• May show extreme variability OR unusual consistency (both patterns possible)
• Absence of typical developmental stuttering features (word fears, avoidances, secondary characteristics)

Associated Psychosocial Triggers 2:

• Stressful life events involving interpersonal conflict
• Difficulty communicating negative emotions in close relationships
• High workplace responsibility with criticism where speaking out is difficult
• Recent accident or illness (even with mild head injury/concussion)
• Personal injury litigation or workers' compensation situations
• Post-traumatic stress disorder

Important caveat: Absence of clear psychological trigger does NOT exclude functional diagnosis 2.

Co-occurring Conditions:

Functional stuttering can coexist with:

• Other functional neurological symptoms
• Comorbid neurological disease (stroke, epilepsy, traumatic brain injury) 2

Other Neurogenic Causes to Consider

Extrapyramidal/Parkinsonian Syndromes

• Parkinsonian-like syndrome can present with stuttering as the first sign 3
• Look for:
  • Resting tremor in hands/legs
  • Gait imbalance
  • Lingual fasciculations
  • Numbness/tingling of extremities
  • Progressive nature of symptoms
• May respond dramatically to carbidopa-levodopa 3

Right Hemisphere Lesions

• More common in women than men (opposite pattern from left hemisphere lesions) 4
• Can occur without aphasia
• Consider family history of developmental stuttering (may indicate genetic susceptibility)

Infectious/Inflammatory

• COVID-19 has been reported to cause new-onset stuttering with word-finding difficulties 5
• May persist for at least 7 days post-acute infection
• Mechanism: spike protein destabilization of blood-brain barrier allowing CNS entry

Diagnostic Algorithm

1. Emergency evaluation: Brain MRI to exclude stroke (within hours of onset if episodic or acute)

2. If imaging negative, neurological examination for:

   • Parkinsonian features (tremor, rigidity, gait abnormality)
   • Other focal neurological signs
   • Signs of other functional neurological symptoms

3. Detailed history:

   • Recent infections (particularly COVID-19)
   • Medications (particularly psychotropics, anticonvulsants)
   • Head trauma (even minor)
   • Psychosocial stressors
   • Litigation/compensation issues
   • Family history of stuttering

4. Speech characteristics assessment:

   • Pattern of dysfluency (every syllable vs. variable)
   • Response to distraction tasks
   • Performance with simple vs. complex speech
   • Presence/absence of secondary behaviors

Common Pitfalls to Avoid

• Do not dismiss episodic stuttering as purely functional without imaging—stroke can present this way 1
• Do not require psychological trigger to diagnose functional stuttering 2
• Do not assume left hemisphere only—right hemisphere lesions cause stuttering in women 4
• Do not overlook extrapyramidal disease—may be treatable with dopaminergic therapy 3
• Do not ignore recent viral illness—COVID-19 can cause persistent neurological speech symptoms 5

Prognosis Considerations

• Functional stuttering: Generally good prognosis with appropriate speech therapy 2
• Stroke-related: Depends on lesion location and extent
• Parkinsonian: May respond dramatically to medical management 3
• Post-infectious: May persist but natural history still being defined 5

The priority is immediate stroke exclusion given the age and acute onset, followed by systematic evaluation for other neurogenic causes before attributing symptoms to functional etiology.