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

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.

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.

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'.

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.