Very low-grade albuminuria is linked to arterial stiffness in a population-based cohort

Albuminuria even at low levels and increased arterial stiffness are associated with higher cardiovascular risk. Very low-grade albuminuria (VLGA; urinary albumin-creatinine ratio [uACR] <30 mg/g) has been linked to adverse outcomes, but its association with arterial stiffness in the general population, particularly among individuals without major cardiometabolic disease, remains uncertain.

We analyzed data from 7613 participants of the German National Cohort (NAKO) with available uACR and brachial-ankle pulse wave velocity (PWV[ba]) measurements. Multivariable linear regression was used to assess the association between log₁₀-transformed uACR and PWV(ba), adjusting for age, sex, systolic blood pressure, obesity indices, LDL-cholesterol, HbA1c, and estimated glomerular filtration rate (eGFR). A low-risk subgroup excluded participants with arterial hypertension or diabetes mellitus.

Among included participants, 49.6 % were female and 7100 (93.3 %) had uACR <30 mg/g. In the full cohort, a 10-fold higher uACR was associated with higher PWV(ba) by 0.10 m/s (95 % CI 0.03-0.17). Similar associations were observed in the VLGA subgroup (0.16 m/s; 95 % CI 0.07-0.25). In the low-risk VLGA subgroup (n = 4308), uACR remained positively associated with PWV(ba) (0.18 m/s per 10-fold higher uACR; 95 % CI 0.08-0.28).

Higher uACR was consistently associated with greater arterial stiffness across the full cohort and among individuals with very low-grade albuminuria, including those without arterial hypertension or diabetes mellitus.