This national cohort demonstrated pronounced regional and etiologic heterogeneity in CKD and revealed stage- and albuminuria-dependent patterns of metabolic complications, supporting the use of KDIGO G-A staging and regional profiles to prioritise etiologic evaluation and tailor laboratory monitoring in low- and middle-income settings.
Diabetic nephropathy and hypertensive nephrosclerosis were the most common causes of CKD in the THAI-CKD cohort.
Chronic kidney disease of unknown aetiology (CKDu) accounted for 22% of all cases overall and showed significant regional concentration.
CKD stage distribution in the cohort was predominantly G3b and G4.
Anaemia and metabolic acidosis showed clear gradients of increasing prevalence with lower estimated glomerular filtration rate and higher albuminuria.
Secondary hyperparathyroidism occurred across all CKD stages but was most frequent in G5, while hyperphosphatemia was mainly observed in G5.
The prevalence of CKD complications varied significantly by both primary aetiology and geographic region after multivariable adjustment.
KDIGO G-A staging and regional profiles are recommended to prioritise etiologic evaluation and tailor laboratory monitoring in low- and middle-income settings.
This research examined why people develop chronic kidney disease (CKD) and what complications they experience across different regions of Thailand. The study analyzed data from over 3,300 adults with moderate-to-severe CKD (stages 3-5) recruited from 41 hospitals nationwide. The most common causes of CKD were diabetes-related kidney damage (41%) and high blood pressure-related kidney damage (34%). Notably, about 22% of cases had no identifiable cause — a condition called CKDu (CKD of unknown aetiology) — which was particularly concentrated in the Central and Western regions of Thailand and tended to occur at earlier, less severe disease stages. The study found that certain complications followed predictable patterns based on how advanced the CKD was. For example, anemia and metabolic acidosis became more common as kidney function worsened and as more protein appeared in the urine. A condition called secondary hyperparathyroidism (abnormal parathyroid hormone levels) appeared at all stages of CKD, while abnormally high phosphate levels were mainly seen in the most severe stage (G5). High potassium levels were surprisingly rare across all disease stages. Importantly, the frequency of these complications also differed depending on what caused someone's kidney disease and which part of Thailand they lived in, even after accounting for other factors. This research suggests that a 'one-size-fits-all' approach to monitoring CKD patients may not be the most efficient use of limited medical resources in lower-income countries. Instead, tailoring laboratory testing schedules and screening priorities based on a patient's disease stage, the amount of protein in their urine, the underlying cause of their kidney disease, and their geographic region could help healthcare systems better target resources. The findings are particularly relevant for other low- and middle-income countries facing similar challenges in managing CKD at a population level.
Jintanapramote K, Srithongkul T, Trakarnvanich T, Sangsuk J, Asawamethapant S, Kittrakulrat J, et al.. (2026). Regional Variation of Aetiologies and Complications in Chronic Kidney Disease From Thailand (THAI-CKD Registry).. Nephrology (Carlton, Vic.). https://doi.org/10.1111/nep.70231