Role of Calcium Levels in Ventilatory Efficiency and Cardiopulmonary Function in Chronic Kidney Disease Patients

Dalili, Nooshin; Jafarian, Amirhossein; Amini, Hossein; Eslaminejad, Alireza; Samavat, Shiva; Kashefizadeh, Alireza

doi:10.22034/rspr.2026.25.1.1490

Role of Calcium Levels in Ventilatory Efficiency and Cardiopulmonary Function in Chronic Kidney Disease Patients

Document Type : Original Article

Authors

Nooshin Dalili ¹

Amirhossein Jafarian ¹

Hossein Amini ²

Alireza Eslaminejad ³

Shiva Samavat ¹

Alireza Kashefizadeh ⁴

¹ Chronic Kidney Disease Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran

² Department of Clinical Pharmacy, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

³ Chronic Respiratory Disease Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran

⁴ Department of Pulmonology, Shahid Labbafinezhad Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

10.22034/rspr.2026.25.1.1490

Abstract

Background: Exercise intolerance is common in patients with chronic kidney disease (CKD) and may reflect abnormalities in cardiovascular function, skeletal muscle performance, and metabolic regulation. This study investigated the associations between selected biochemical parameters and cardiopulmonary function in adults with non-dialysis CKD stages 3–5.
Materials and Methods: This observational cross-sectional study included 80 adults with non-dialysis chronic kidney disease (CKD) stages 3–5. Demographic characteristics, clinical history, laboratory measurements, and cardiopulmonary exercise testing (CPET) parameters were assessed. Logistic regression analyses were performed to investigate factors associated with increased ventilatory demand during exercise, and receiver operating characteristic (ROC) analyses were used to evaluate the discriminatory performance of selected biochemical parameters.
Results: The study population was predominantly male (62.5%), with a mean age of 42 years. The univariable analysis identified that only the mean serum vitamin D differed among the various serum calcium levels (P<0.001). Specifically, individuals with calcium levels ≥ 8.6 mg/dL (P=0.009) and those with calcium levels ranging from 8 to 8.6 mg/dL (P=0.001) had lower mean vitamin D levels compared to individuals with calcium levels ≤ 8 mg/dL. In the final multivariable model, it was found that only serum calcium levels had a statistically significant association with increased ventilation demand during exercise (VE/VCO₂ >35 L/min). Specifically, patients with serum calcium levels ≥ 8.6 mg/dL had approximately 7 times higher odds of increased ventilation demand (VE/VCO₂ >35 L/min) compared to those with calcium levels ≤ 8 mg/dL (P=0.041).
Conclusion: This study underscores the intricate interplay between biochemical markers and cardiopulmonary health in CKD patients, providing insights into exercise intolerance. Serum calcium levels may hold diagnostic value, warranting further investigation into their clinical utility.

Keywords

Renal insufficiency

Cardiopulmonary function

Ventilatory efficiency

Calcium

Subjects