Prevalence and factors associated with malnutrition among patients with pre-dialysis chronic kidney disease stages 3-5.

Malnutrition is a common and clinically significant complication in patients with chronic kidney disease (CKD), contributing to increased morbidity and mortality. However, evidence regarding its prevalence and associated factors in pre-dialysis CKD remains limited. The aim of this study was to determine the prevalence of malnutrition, compare its distribution across CKD stages, and identify factors associated with malnutrition in patients with pre-dialysis CKD stages 3-5. This cross-sectional study included patients with CKD stages 3-5 attending the nephrology clinic at Rajavithi Hospital, Thailand, between January and December 2025. Nutritional status was assessed using the Nutrition Alert Form (NAF). Demographic, clinical, dietary, and laboratory data were collected. Factors associated with malnutrition were analyzed using logistic regression. A total of 313 patients were included. The prevalence of malnutrition was 39.30%, including 34.50% moderate and 4.79% severe malnutrition. Independent factors associated with malnutrition included underweight (adjusted OR (aOR): 5.10; 95%CI: 1.26-20.68), severe obesity (aOR: 7.33; 95%CI: 2.53-21.22), history of stroke (aOR: 85.23; 95%CI: 19.23- 377.70), weight loss within 4 weeks (aOR: 7.55; 95%CI: 2.92-19.51), increased weight within 4 weeks (aOR: 3.10; 95%CI: 1.19-8.07), reduced dietary intake (aOR: 46.42; 95%CI: 10.39-207.38), impaired food access (aOR: 10.63; 95%CI: 2.88-39.23), CKD stage 5 (aOR: 2.22; 95%CI: 1.14-4.31), higher serum creatinine (aOR: 1.86; 95%CI: 1.19- 2.90), and lower lymphocyte percentage (aOR: 0.93; 95%CI: 0.89-0.97). Malnutrition was highly prevalent among patients with pre-dialysis CKD stages 3-5, and the findings suggest a possible U-shaped association between body habitus and malnutrition, with both underweight and severe obesity independently associated with increased nutritional risk. These findings support the importance of routine nutritional screening across all CKD stages regardless of BMI status and may help identify patients at increased nutritional risk.