Table 2.

The Reported Prevalence of Chronic Urticaria in the Elderly Population

Study (year)	Study design	Country	Population	Reported chronic urticaria among all elderly patients N/Total (%)
Chronic urticaria
Gaig et ala (2004)29	Cross-sectional	Spain	Spanish population National telephone directory survey	10/1,047 (1.0)
Lapi et alb (2016)35	Retrospective cohort	Italy	Italian population The Health Search IMS Health Longitudinal Patient Database	13,476/488,145 (2.8)
Wertenteil et alc (2019)33	Cross-sectional study	USA	Multihealth system data analytics and research platform	22,900/9,757,210 (0.2)
Gaber et al (2020)46	Prospective cohort	Egypt	Outpatient clinic University Hospital	2/260 (0.8)

Notes: ^aGaig et al conducted a population-based study among adults in Spain. Population sample was randomly selected from a national telephone directory. The phone survey was performed with each individual employing the Computer-assisted Telephone Interview technique. ^bThe database from the Health Search IMS Health Longitudinal Patient Database (HSD) contained the computer-based patient records from about 1,000 general practitioners (GPs) throughout Italy. Included in this study were almost 1 million electronic patient records which met standard quality criteria. They were selected on a geographical basis to represent the whole Italian population. ^cElectronic health records data for a demographically heterogenous population-based sample of >55 million patients. The database is from 27 participating integrated health care organizations, representing over 55 million unique persons (17% of the population across all four census regions of the United States).