{"doi":"10.1093/bjd/ljac061","title":"Is vaccination against COVID-19 associated with psoriasis or eczema flare? Self-controlled case series analysis using data from the Clinical Practice Research Datalink (Aurum)","abstract":"https://doi.org/10.1093/bjd/ljac061 Dear Editor, Case reports and uncontrolled case series have reported psoriasis and eczema flares following COVID-19 vaccination,1–3 lending credence to the idea that vaccination could trigger disease flares. Up to 54% of vaccine-hesitant patients with psoriasis cite apprehension of disease flare as their primary reason for vaccine hesitancy.4–6 To the best of our knowledge, no adequately controlled study has assessed the association between COVID-19 vaccination and skin disease flare. We investigated the risk of flare of psoriasis or eczema following COVID-19 vaccination using data from the Clinical Practice Research Datalink (CPRD) Aurum. CPRD is a longitudinal anonymized electronic database of health records from 19 million patients in the UK7 and includes information on demographic and lifestyle factors, diagnoses, primary-care prescriptions and vaccinations. This study was approved by CPRD Research Data Governance (reference: 21_000670). This study used data from the CPRD. Due to the CPRD data sharing policy, we are unable to share this study’s data. However, access to CPRD data can be directly requested from the CPRD. Self-controlled case series analysis was used in this study. This analytical method uses data from exposed participants who also develop an outcome, and accounts for between-person confounding.8 It is extensively used in vaccine safety studies. Inclusion criteria were adults aged ≥ 18 years, with at least one primary-care consultation for atopic dermatitis/eczema or psoriasis, with or without arthritis, who received at least one primary-care prescription of conventional immune-­suppressing treatments, provided they also received at least one vaccination against COVID-19 and consulted their general practitioner for at least one skin flare between 1 December 2020 and 31 December 2021. Vaccination and vaccine brand were defined using product codes and vaccination dates. COVID-19 was defined using either general practitioner diagnosis or test results recorded in the CPRD. Skin disease flare was defined as primary-care consultation with diagnostic coding for atopic dermatitis/eczema or cutaneous psoriasis and prescription of drug(s) used for skin disease flare on the same or subsequent date without prescription of the qualifying drug in the preceding 90 days. This minimized the possibility of routine consultations and repeat prescriptions being defined as disease flare. Date of primary-care consultation was the outcome date. Participants contributed data from multiple flares; however, consultations within 14 days were considered part of the same flare. The study period (1 December 2020 to 31 December 2021) was divided into 21 days vaccine exposed, 7 days prevaccination and the remaining vaccine-unexposed periods. The vaccine-exposed period was 21 days postvaccination as it takes approximately 1–2 weeks for COVID-19 immunization to induce an immunological response. We hypothesized that this period of immune reconstitution was most likely to be associated with increased disease activity. As patients with disease flare may delay vaccination, the 7 days preceding vaccination were considered separate from the vaccine-unexposed period to minimize potential reverse causation. A Poisson model conditioned on the number of events and adjusted for seasons was fitted to calculate the adjusted incidence rate ratio and 95% confidence interval for the association between vaccination and skin flares. Stratified analysis considered different vaccine doses, technology of first vaccine received and type of skin disease. COVID-19 infection before the first vaccination had follow-up censored at the second dose. Data were analysed using Stata v.16 (StataCorp LLC, College Station, TX, USA). A two-sided P < 0·05 was considered statistically significant. Data for 1963 patients were included, with 1770 (90·2%), 178 (9·1%) and 15 (0·8%) patients having had one, two and three skin disease flares, respecti","journal":"British Journal of Dermatology","year":2022,"id":281880,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":8,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9531,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":957530,"name":"Georgina Nakafero","orcid":"0000-0002-3859-7354","position":1,"is_corresponding":false},{"id":957531,"name":"Matthew J. Grainge","orcid":"0000-0001-7181-4042","position":2,"is_corresponding":false},{"id":957532,"name":"Tim Card","orcid":"0000-0003-2555-2250","position":3,"is_corresponding":false},{"id":957533,"name":"Christian Mallen","orcid":"0000-0002-2677-1028","position":4,"is_corresponding":false},{"id":957534,"name":"Jonathan S. Nguyen‐Van‐Tam","orcid":"0000-0003-2579-4655","position":5,"is_corresponding":false},{"id":68465,"name":"Hywel C Williams","orcid":"0000-0002-5646-3093","position":6,"is_corresponding":false},{"id":406255,"name":"Abhishek Abhishek","orcid":"0000-0003-0121-4919","position":7,"is_corresponding":false},{"id":957529,"name":"Laura Adams","orcid":"0000-0003-4824-7195","position":0,"is_corresponding":true}],"reference_count":10,"raw_metadata":null,"created_at":"2026-07-19T00:29:15.734856Z","pmid":"36763860","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}