Microscopic haematuria linked to chronic kidney disease

Individuals with microscopic haematuria, especially persistent haematuria, appear to be at heightened risk of chronic kidney disease (CKD), as shown in a study.

The retrospective study used data from the Kangbuk Samsung Health Study and included 232,220 Korean adults without CKD at baseline. They underwent repeated health examinations, including testing for microscopic haematuria (≥5 red blood cells per high-power field).

Participants were grouped into four, according to the presence of haematuria at two consecutive examinations: a) no haematuria in both instances (reference group), b) haematuria followed by its absence (regressed haematuria group), c) no haematuria followed by its presence (developed haematuria group), and d) haematuria in both instances (persistent haematuria).

Over a follow-up of 4.8 years, 2,392 participants developed CKD (defined as an estimated glomerular filtration rate <60 ml/min/1.73 m² or proteinuria on dipstick examination).

Multivariable proportional hazards models showed the risk of CKD was elevated across all haematuria groups as compared with the reference group. The corresponding hazard ratios were 1.85 (95 percent confidence interval [CI], 1.35–2.53) in the regressed group, 3.18 (95 percent CI, 2.54–3.98) in the developed group, and 5.23 (95 percent CI, 4.15–6.59) in the persistent group.

Additionally, the association between persistent haematuria and incident CKD was more pronounced in men than in women (p_interaction<0.001), although a significant association was observed in both sexes.

The study was limited by the lack of data on albuminuria and inability to consider specific glomerular diseases.