Changes of b2-microglobulin and electrolytes in different stages of COPD and their value in evaluating prognosis.

Background: To investigate the changes of b2-microglobulin and electrolyte in different stages of chronic obstructive pulmonary disease (COPD) and the value of evaluating prognosis.

Methods: A retrospective study was undertaken on 120 patients diagnosed with COPD and treated at our respiratory department between February 1, 2020, and January 31, 2023. These patients were classified into three groups based on the GOLD classification: mild (FEV1 > 81%), moderate (51% < FEV1 ≤ 80%), and severe (FEV1 ≤ 50%). As a control group, 40 healthy individuals who had routine examinations during the same period were selected. The COPD patients were then followed up and divided into a good prognosis group (n = 67) and a poor prognosis group (n = 53). The levels of b2-microglobulin and electrolytes were measured in patients with different stages of the disease and different prognoses. Kendall's tau-b and ordered logistic regression were employed to analyze how the changes in b2-microglobulin and electrolyte levels correlated with disease severity. Furthermore, the prognostic value of b2-microglobulin and electrolyte levels in COPD was assessed using an ROC curve.

Results: In comparison to the control group, the severity of COPD patients displayed a notable increase in b2microglobulin levels, while there was a significant decrease in levels of calcium, chlorine, potassium, and sodium. Kendall's tau-b correlation coefficient analysis indicated a positive correlation between COPD severity and b2microglobulin, and a negative correlation between COPD severity and levels of calcium, chlorine, potassium, and sodium. Logistic regression analysis revealed that there was a positive correlation between disease severity and b2microglobulin, and a negative correlation between disease severity and levels of calcium, chlorine, potassium, and sodium. Furthermore, the poor prognosis group exhibited a significant increase in b2-microglobulin levels, alongside a significant decrease in levels of calcium, chlorine, potassium, and sodium compared to the good prognosis group (P < 0.05). ROC curve analysis demonstrated that a combined detection of b2-microglobulin, calcium, chlorine, potassium, and sodium yielded significantly higher area under the curve, sensitivity, and specificity values compared to single detection methods, highlighting its significant predictive value for COPD prognosis.

Conclusions: Patients who presented with a more severe form of the disease exhibited elevated levels of b2microglobulin and reduced electrolyte levels. Prognostic accuracy was significantly enhanced when b2-microglobulin and electrolyte levels were analyzed together, offering a superior method for predicting patient outcomes.