CAP: community-acquired pneumonia; DM: diabetes mellitus; GV: glycemic variability; SNP: single-nucleotide polymorphism; AGER: receptor for advanced glycaton endproducts; sRAGE: soluble receptor for advanced glycation endproducts; ARDS: acute respiratory distress syndrome; AECOPD: acute exacerbation of chronic obstructive pulmonary disease. This evidence concerns the gene AGER and chronic obstructive pulmonary disease.