Our objective is to explore the effects of budesonide combined with noninvasive ventilation on procalcitonin (PCT), soluble myeloid cell triggering receptor-1 (sTREM-1), thoracic and lung compliance, humoral immune function, and quality of life in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) complicated with type II respiratory failure. This evidence concerns the gene CALCA and chronic obstructive pulmonary disease.