Microalbuminuria is associated with cardiovascular disease (CVD) mortality but whether lower levels of urine albumin excretion similarly predict CVD is uncertain. We investigated associations between urine albumin:creatinine ratio (UACR) < 30mg/g, and incident hypertension, incident diabetes, all cause and CVD mortality, at 10 year follow-up.Design and Method:
39,071 individuals in a health screening program between 2002 and 2012 (N = 39,071) with baseline measurements of urine albumin creatinine ratio (UACR) were studied. Cox proportional hazards models were used to estimate hazard ratios (HRs and 95% confidence intervals for incident hypertension, incident diabetes and mortality outcomes (lowest UACR quartile as reference) at follow-up. For linear risk trends, the quartile rank was used as a continuous variable in regression models.Results:
963 cases of incident hypertension, 511 cases of incident diabetes and 349 deaths occurred during follow-up. In the fully adjusted models, there was a significant HR for the association between UACR and incident hypertension [highest UACR quartile HR 1.95 (95% CI 1.51,2.53), p value for trend across UACR quartiles p < 0.001]. In contrast, the association between UACR and incident diabetes was not significant [highest UACR quartile, HR 1.15 (95%CI 0.79,1.66), p value for trend p = 0.20]. For CVD mortality, with increasing UACR quartiles, there was a significant increase in HR across quartiles, p = 0.029, (for all cause mortality, p = 0.078).Conclusions:
Low grade albuminuria, below the levels of microalbuminuria, is associated with increased risk of incident hypertension and CVD mortality at follow up, but is not associated with increased risk of incident diabetes.