Health-related quality of life in Danish patients with hereditary angioedema.

Hereditary angioedema (HAE) is a rare, but potentially life-threatening disease characterised by attacks of swellings. It is caused by a lack of functioning C1 esterase inhibitor (C1INH). The oedema is usually located to the face, extremities or abdominal mucosa, but may involve the larynx. Although rare, the laryngeal attacks are particularly dreaded due to the risk of asphyxiation. It is known that HAE can have substantial impact on health-related quality of life (HRQoL) (1, 2). Today, Danish HAE patients have access to several modalities of treatment including intravenously administered C1INH concentrate (3). Patients are offered training in self-injection if they suffer from frequent and/ or severe attacks. The aim of this study was to investigate HRQoL in Danish HAE patients. METHODS The study was carried out in 2009 at the Danish HAE Comprehensive Care Centre, Odense University Hospital. Twenty-seven Danish HAE patients filled out The Short Form (36) Health Survey , version 2 (SF-36v2) and a clinical questionnaire. Patients were asked about number and locations of attacks within the last 6 months, age of onset, types of treatment and ability to do self-injection. Danish population norms for SF-36v2 were not available, it was recommended by the producers to compare to the US population norms (4). To examine if there was any correlation between disease severity and score in SF-36v2, a clinical severity score recently developed by Bygum et al. (5) was used. Patients were divided into 3 groups based on disease severity, and for each group median scores in SF-36v2 were calculated. We also examined whether scores in SF-36v2 were related to self-injection with C1INH concentrate by calculating median scores for the self-injecting and non-self-injecting subgroup, respectively. RESULTS Fig. 1 outlines the SF-36v2 mean score reported for 8 specific dimensions. In all dimensions but one, HAE patients rate equally to or higher than the general population. The relation between disease severity and median scores in SF-36v2 is illustrated with a box and whiskers plot (Fig. 2). In all dimensions there is no statistically significant difference in median score between the 3 severity groups (p > 0.05 in Kruskall-Wallis test). In the study, 25 patients had C1INH concentrate at home and 11 were able to do self-injection. In the dimension General health the self-injecting subgroup scored lower than the non-self-injecting subgroup (median Mann Whitney U rank-sum test). Otherwise there was no difference between the 2 groups. Nor did we find any …