The global burden of chronic urticaria for the patient and society.

Chronic urticaria (CU) affects about 1% of the world population of all ages, mostly young/middle-aged females, usually lasts for several years (>1 year in 25-75% of patients), and often takes >1 year before effective management is implemented. It presents as chronic spontaneous urticaria (CSU), chronic inducible urticaria (CIndU) or both in the same person. More than 25% of cases are resistant to H1-antihistamines, even at higher doses, and 3rd and 4th line therapy (omalizumab and ciclosporin) control the disease only in two thirds of H1 -antihistamine resistant patients. Here, we review the impact of CU on different aspects of patients' QoL and the burden of this chronic disease for the patient and the society. CU may have a strong impact on health-related quality of life (HRQoL), particularly when CSU is associated with angioedema and/or CIndU (DLQI>10 in 30% of patients). Comorbidities, such as anxiety and depression, that are present in more than 30% of CSU patients compound HRQoL impairment. Severe pruritus and the unpredictable occurrence of wheals and angioedema are responsible for sleep disorders, sexual dysfunction, limitations on daily life, work and sports activities, interfering with life within the family and in society and with patients' performance at school and work (6% absenteeism and 25% presenteeism). Apart from treatment costs, with annual values between 900-2.400 PPP$ (purchasing power parity dollars) in Europe and US, CU is associated with a high consumption of medical resources and other indirect costs, which may reach a total annual cost of 15.550 PPP$.