woman narcolepsy

“How do I know if I may have cataplexy?”

Combining the clinical interview with the use of the Swiss Narcolepsy Scale (SNS).

Interviewing tips and techniques for helping identify patients with cataplexy.

  • Because patients may consider the sensation of some attacks to be normal, probe for subtle manifestations.1-3
  • Inquire about specific muscle groups since cataplexy most often occurs in common patterns in an individual patient.1,3
  • Consider having the patient’s partner participate in the clinical interview.1,3
Key questions to ask to help identify cataplexy.

Key questions to ask to help identify cataplexy.

It may be helpful to ask...1,3-5

  • How often has the patient experienced weak knees or knees buckling during emotions such as laughing, happiness, or anger?
  • How often has the patient experienced sagging of the jaw during emotions such as laughing, happiness, or anger?
  • Does the patient take measures to try to prevent a cataplexy attack or reduce its severity or duration?
    • Examples include sitting down, trying to think of something else, putting tension on muscles, or pressing against a firm support surface.
  • Does the patient avoid situations or emotions that may trigger cataplexy?
  • Is the patient taking any medications that may suppress cataplexy (eg, antidepressants)?

Using the SNS, a validated tool for screening for narcolepsy with cataplexy.5-7

  • In one study, the SNS was shown to have a sensitivity of 96% and a specificity of 98% for identifying a symptom profile suggestive of narcolepsy with cataplexy.6
  • Patients rate the frequency of individual symptoms based on a 5-point scale.5,6
  • Each answer is weighted by a positive or negative factor, according to the following equation:
    • (6 x Q1) + (9 x Q2) – (5 x Q3) – (11 x Q4) – (13 x Q5) + 20 = TOTAL SCORE
Those answers relating to cataplexy receive the most negative ratings.5,6
An SNS score of less than 0 is suggestive of narcolepsy with cataplexy.5-7*

Administering the SNS questionnaire.5

Fill out this interactive form to become more familiar with the questionnaire for yourself, or use it together with your patients. Just select the answers below that best apply for each situation.

How often are you unable to fall asleep?

Never
Rarely
Less than once a month
Sometimes
1-3 times a month
Often
1-2 times a week
Almost Always

How often do you feel bad or not well rested in the morning?

Never
Rarely
Less than once a month
Sometimes
1-3 times a month
Often
1-2 times a week
Almost Always

How often do you take a nap during the day?

Never
I would like, but cannot
1-2 times a week
3-5 times a week
Almost Daily

How often have you experienced weak knees/buckling of the knees during emotions like laughing, happiness, or anger?

Never
Rarely
Less than once a month
Sometimes
1-3 times a month
Often
1-2 times a week
Almost Always

How often have you experienced sagging of the jaw during emotions like laughing, happiness, or anger?

Never
Rarely
Less than once a month
Sometimes
1-3 times a month
Often
1-2 times a week
Almost Always
Calculate
Total Score : 0
The Swiss Narcolepsy Scale5

Your SNS score is:

0

An SNS calculated score that is less than 0 is suggestive of narcolepsy with cataplexy. You should discuss your SNS score with your sleep specialist.

Interpreting SNS Scores5,6

-50

-40

-30

-20

-10

0

6

Suggestive of narcolepsy with cataplexy
Not suggestive of narcolepsy with
cataplexy

-50

-40

-30

-20

-10

0

6

Suggestive of narcolepsy with cataplexy
Not suggestive of narcolepsy with
cataplexy

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*A diagnosis of narcolepsy with cataplexy should be established by clinical interview and laboratory testing.1

Learn more about

ICSD-3 CRITERIA FOR
NARCOLEPSY TYPE 1