Renal Dysfunction in Chronic Obstructive Pulmonary Disease Lung–Kidney Interorgan Crosstalk with Cardiac Mediation

Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a systemic disorder with clinically significant extrapulmonary manifestations. Among these, renal dysfunction—manifesting as chronic kidney disease (CKD) and acute kidney injury (AKI)—is highly prevalent, frequently underdiagnosed, and strongly associated with adverse clinical outcomes. Meta-analytic data indicate that COPD is associated with more than a twofold increase in CKD prevalence, independent of shared risk factors such as age, smoking, hypertension, and diabetes. CKD in COPD is associated with increased mortality, exacerbation burden, and healthcare utilization. AKI represents a particularly severe expression of renal involvement, occurring most commonly during acute exacerbations of COPD (AECOPD). Although the reported incidence of AKI during AECOPD varies widely by clinical setting—from approximately 2% in population-based studies to over 20% in hospitalized cohorts—its presence is consistently associated with marked increases in mortality, respiratory failure, need for mechanical ventilation, and hospital length of stay. This review synthesizes current evidence supporting a lung–kidney interorgan crosstalk framework in COPD, whereby chronic and acute pulmonary pathophysiology generates systemic disturbances that progressively impair renal structure and function. The heart is incorporated as a physiological intermediary, modulating hemodynamic transmission and venous congestion, without constituting the primary disease axis. Recognizing the role of kidney complications in COPD is crucial, as it influences how we diagnose, predict outcomes, and treat patients—especially when there are sudden flare-ups.