Up-dosing non-sedating antihistamines in patients with chronic spontaneous urticaria: A systematic review and meta-analysis
Guillén-Aguinaga S (1), Jáuregui Presa I (2), Aguinaga-Ontoso E (3), Guillén-Grima F (4,5), Ferrer M (5,6).
There is a lack of large, randomized, double-blind studies that address antihistamine up-dosing for chronic spontaneous urticaria (CSU).
To explore and analyze available data to provide clinical evidence for antihistamine up-dosing.
We searched literature using the keywords "chronic, urticaria, antihistamines" in the Medline, Scopus, Google Scholar, Embase, Web of Science and Cochrane databases between January 1990 and November 2014. We assessed quality with the Jadad score that evaluates quality of randomization, double blinding, and losses to follow-up.
We identified 1,042 articles, including 15 in the final evaluation. We performed two meta-analyses, one including studies that analyzed treatment response among groups receiving different antihistamine doses versus placebo, and another that analyzed antihistamine up-dosing in those patients who did not respond to standard doses.
Only five articles reached a high quality level. We did not find significant differences in rate's response or number of wheals between those patients who received a standard dose vs. a high dose. We found a significant improvement only in the pruritus variable of the urticaria activity score (UAS) scale.
The estimated relative risk for improvement by increasing the antihistamine dose was 2.27 (95% CI 1.68-3.06); however, there was significant heterogeneity. The proportion of non-respondent CSU patients who responded to antihistamine up-dosing was 63.2% (95% CI 57-69.6%).
We found that up-dosing antihistamines significantly improved control of pruritus but not of wheal number. However, the relative weakness of the studies and the significant heterogeneity among them made it difficult to reach a final conclusion.