Prevalence of Respiratory Complications in Chronic Kidney Disease Patients: A Cross-sectional Study

Abstract

Background: Respiratory complications are increasingly recognized as significant comorbidities in chronic kidney disease (CKD) patients, yet their prevalence and clinical characteristics remain inadequately documented in the Indian population.

Objectives: This study aimed to determine the prevalence, types, and severity of respiratory complications in CKD patients across different disease stages and to identify the association between kidney function decline and pulmonary dysfunction.

Methods: A cross-sectional observational study involving 150 CKD patients (stages 1–5) from Kidney Care Centre, Tirunelveli was conducted. Respiratory assessment included modified Medical Research Council (mMRC) dyspnea scale, spirometry, 6-minute walk test (6MWT), peripheral oxygen saturation (SpO₂), chest imaging, and modified Borg exertion scale. Multivariate analysis examined associations between CKD stage and respiratory complications.

Results: Pulmonary edema was the most prevalent respiratory complication (24.84%), followed by pneumonia (18.2%), pleural effusion (16.5%), tuberculosis (12.3%), and obstructive sleep apnea (10.1%). Mean FEV₁ % predicted significantly declined from Stage 1 (95%) to Stage 5 (42%, p<0.001). Mean 6MWT distance decreased progressively (Stage 1: 487m vs Stage 5: 268m, p<0.001). Dyspnea severity correlated significantly with advancing CKD stage (r=0.78, p<0.001). SpO₂ below 92% was observed in 31.3% of Stage 4–5 patients. Multivariate analysis identified CKD stage (OR=2.41, 95% CI: 1.89–3.07), dialysis status (OR=1.87, 95% CI: 1.23–2.84), and anemia (OR=1.56, 95% CI: 1.02 2.38) as independent predictors of respiratory complications.

Conclusion: Respiratory complications are highly prevalent in CKD patients with significant functional impairment and disease progression across kidney stages. Early respiratory assessment and integrated management strategies are essential for comprehensive CKD care and improved patient outcomes.