ABO and Rh blood group distributions in patients with primary spontaneous pneumothorax: a comparative population-based study across two altitudes.

BACKGROUND

First described in the early 19th century as “simple pneumothorax,” primary spontaneous pneumothorax (PSP) refers to the presence of air within the pleural cavity without an identifiable secondary cause. PSP predominantly affects males, smokers, tall individuals, and those with a low body mass index. However, the occurrence of PSP in individuals without classical risk factors suggests that additional biological or genetic mechanisms may contribute to disease susceptibility. ABO and Rh blood group antigens are genetically determined traits that have been associated with susceptibility to several pulmonary and systemic diseases; however, data regarding their relationship with PSP remain limited. This study aimed to evaluate whether ABO and Rh blood group subtypes are associated with PSP by analyzing a homogeneous surgical patient cohort from two cities with distinct altitudes and comparing the findings with national blood group distribution.

METHODS

A total of 174 patients who underwent surgery for PSP between 2021 and 2024 were retrospectively reviewed from two centers located in geographically distinct altitude regions. ABO and Rh distributions were analyzed using Pearson’s chi-square test, inverse probability of treatment weighting (IPTW), and one-sample Z testing.

RESULTS

The overall distribution of ABO blood groups and Rh factor in PSP patients was largely comparable to national population data, although blood group O appeared to be less frequently observed.

CONCLUSIONS

The distribution of ABO and Rh blood groups in patients undergoing surgery for primary spontaneous pneumothorax largely comparable from national population data. These findings suggest a possible potential relationship blood group characteristics and PSP; however, due to the retrospective design and the absence of a matched control group, causal inferences cannot be made. Further prospective studies with appropriate control populations are required to clarify the potential role of blood group–related genetic factors in PSP susceptibility. These findings may provide hypothesis-generating evidence suggesting that genetically determined blood group traits could contribute to individual susceptibility to primary spontaneous pneumothorax.