Common Variable Immune Deficiency Disorders (CVID) in the Indigenous Māori of Aotearoa (New Zealand) Are Associated With a High Prevalence of Bronchiectasis and Complete IgA Deficiency.

The New Zealand (NZ) Common Variable Immunodeficiency Disorders (CVID) study (NZCS) is a long-term prospective cohort study, which seeks to better understand the proximal causes and sequelae of CVID. Patients were accepted to the NZCS if they had a diagnosis of CVID. After informed consent, clinical and demographic data were obtained by an interviewer-assisted questionnaire. Computerised case notes and laboratory results, linked to each patient's National Health Index (NHI) number, were also reviewed. In the current analysis, ethnic-specific data was obtained on the prevalence of CVID and its sequelae in NZ. One hundred and eight patients with a diagnosis of CVID were enrolled in the NZCS, comprising approximately 70% of patients known to have CVID in NZ. There was a much greater prevalence of bronchiectasis in Māori (79%) compared to Caucasian CVID patients (38%). Māori patients with CVID develop symptoms at a younger age and have an increased number of severe infections prior to diagnosis. Māori CVID patients with bronchiectasis had a higher prevalence of complete IgA deficiency compared to Caucasian CVID patients with bronchiectasis. In contrast to Caucasian patients with CVID, autoimmune and inflammatory sequelae were much less common in Māori. This study also demonstrated worsening diagnostic delays in patients with CVID in NZ. The Indigenous Māori of Aotearoa have a much more aggresssive early-onset, infection-only CVID variant compared to Caucasian New Zealanders.