Chronic subjective dizziness: Fewer symptoms in the early morning--a comparison with bilateral vestibulopathy and downbeat nystagmus syndrome.

Objective: Chronic subjective dizziness (CSD) is a form of chronic dizziness. Many patients report fewer symptoms when they get up with an aggravation over of the day. Therefore, the change in the severity of the symptoms during daytime was evaluated and compared with other chronic vestibular diseases: bilateral vestibulopathy (BVP) and downbeat nystagmus (DBN).

Design/methods: In a prospective study 131 patients with CSD, 108 patients with BVP, and 38 patients with DBN filled out a questionnaire asking about the symptom intensity (0 = no symptoms, 1 = light, 2 = moderate, 3 = strong) at 6 time-points. The influences of duration of the disease and physical activity on the change of symptoms were also investigated.

Results: The symptom intensity score in CSD was lower after getting up in comparison to later time points. In BVP a strong sensation of dizziness after getting up with worsening in the evening was observed. In DBN symptoms significantly improved during daytime. In BVP, the symptom intensity scores were significantly higher in patients with symptoms more than six month as less than six month. In the other groups, no association between duration of illness and intensity of perceived dizziness could be seen.

Conclusion: There are considerable differences in the change in symptoms between the three diseases. Taking the patient history simply asking how the symptoms are when the patient gets up in the morning and how they change during daytime can be helpful in the differential diagnosis. Having less or no symptoms after getting up may be a diagnostic criterion for CSD.