Muscle Weakness
Conditions
Brief summary
We intend to measure evoked EMG at two sites in subjects who are chronically taking pyridostigmine.
Detailed description
The investigators are intending to enroll Patients who are chronically treated with pyridostigmine for the treatment of any medical condition and presenting at the investigators' outpatient clinics for follow up appointment. Subjects taking pyridostigmine for the treatment of myasthenia gravis will be excluded. Both adults and children older than 12 years of age will be approached. Those subjects that agree to participate will be asked to sign an informed consent. For the participation of minors a parental (or guardian) consent and subject assent will be obtained. Those that participate will answer a few questions pertaining to their medical history and will then undergo electromyograph (CMAP) measurement with repetitive stimulation at 2 sites (ulnar nerve at the wrist and the accessory nerve in the neck). Evoked electromyogram will be recorded on a computer hard drive. Eight percent or greater decrement in the CMAP response on repetitive stimulation will be considered positive.
Interventions
DIAGNOSTIC_TESTElectromyography (EMG)
Sponsors
University of Toledo Health Science Campus
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Intervention model description
All subjects taking Pyridostigmine for at least 6mo, except for myasthenia gravis patients, will be considered for the study.Those that participate will answer a few questions pertaining to their medical history and will then undergo electromyography (CMAP) measurement with repetitive stimulation at 2 sites (ulnar nerve at the wrist and the accessory nerve in the neck). The first and fifth stimuli are delivered 2 seconds apart. Eight percent or greater decrement in the CMAP response on repetitive stimulation will be considered positive.
Eligibility
Sex/Gender
ALL
Age
12 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* Subjects who have been taking pyridostigmine for the treatment of any condition other than myasthenia gravis
Exclusion criteria
* Subjects taking pyridostigmine for the treatment of myasthenia gravis will be excluded.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent Change in the Amplitude of Evoked Compound Muscle Action Potential by Electromyography Between the First to Fifth Response | Baseline measurement only. First and Fifth stimuli delivered 2 seconds apart on the same day. There are no additional days/times. | Normally when a nerve is rapidly stimulated the successive Compound Muscle Action Potentials (CMAP) are of the same height. We are hoping to investigate if chronic pyridostigmine therapy reduces the margin of safety and hence the successive CMAPs may be smaller than the preceding ones. |
Countries
United States
Participant flow
Recruitment details
All subjects taking Pyridostigmine for at least 6months, except for the treatment of myasthenia gravis, will be considered. Subjects will be recruited from existing patients treated at the university and will be seen in the outpatient clinics.
Participants by arm
| Arm | Count |
|---|---|
| Pyridostigmine Bromide Treatment Group All subjects investigated were taking pyridostigmine. | 11 |
| Total | 11 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Screen Fail | 1 |
Baseline characteristics
| Characteristic | Pyridostigmine Bromide Treatment Group |
|---|---|
| Age, Continuous | 63 years |
| Sex: Female, Male Female | 5 Participants |
| Sex: Female, Male Male | 6 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 10 |
| other Total, other adverse events | 0 / 10 |
| serious Total, serious adverse events | 0 / 10 |
Outcome results
Primary
Percent Change in the Amplitude of Evoked Compound Muscle Action Potential by Electromyography Between the First to Fifth Response
Normally when a nerve is rapidly stimulated the successive Compound Muscle Action Potentials (CMAP) are of the same height. We are hoping to investigate if chronic pyridostigmine therapy reduces the margin of safety and hence the successive CMAPs may be smaller than the preceding ones.
Time frame: Baseline measurement only. First and Fifth stimuli delivered 2 seconds apart on the same day. There are no additional days/times.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Pyridostigmine Bromide Treatment Group | Percent Change in the Amplitude of Evoked Compound Muscle Action Potential by Electromyography Between the First to Fifth Response | 0 percent change |