Responsiveness of AF6, a new, short, validated, atrial fibrillation-specific questionnaire—symptomatic benefit of direct current cardioversion

OBJECTIVES: To measure the effects on symptoms of electrical cardioversion (DC) in patients with atrial fibrillation (AF) by means of a new, short, validated, AF-specific questionnaire, the AF6. METHODS: One hundred eleven patients (67 ± 12 years, 89 men) were screened before and 12 ± 3 days after DC using AF6, covering 'breathing difficulties at rest', 'breathing difficulties on exertion', 'limitations in day-to-day life due to atrial fibrillation', 'feeling of discomfort due to atrial fibrillation', 'tiredness due to atrial fibrillation', and 'worry/anxiety due to atrial fibrillation'. A single global score was calculated. The Toronto AF Symptoms and Severity Check List (AFSS) and the generic SF-36 were also administered. Patients in sinus rhythm at 12 ± 3 days (n = 56) were defined as responders and patients in AF (n = 55) as non-responders. RESULTS: The mean single global score decreased in all patients (18 ± 12.4 to 13 ± 11.6, p < 0.0001) and in responders (22 ± 14 vs. 12 ± 12, p < 0.01) but not in non-responders (14 ± 9 vs. 14 ± 11, N.S). The AFSS frequency scores decreased from 14.5 ± 7.7 to 9.5 ± 7.8 in responders, p = 0.001, but not in non-responders. There was a strong correlation between changes in the AF6 and the SF-36 regarding four of the six items. Effect sizes of AF6 ranged from 0 to 0.52 in all patients, in responders from 0.10 to 0.85 and in non-responders from -0.23 to 0.34, the highest figures consistently referring to 'tiredness due to atrial fibrillation'. CONCLUSIONS: The symptom scores measured by AF6 decreased significantly, especially in responders. AF6 demonstrated adequate responsiveness to change, and effect sizes were mostly moderate, in responders moderate to high.