Temporal variation in cardiovascular disease risk predicted by albuminuria: An opportunity for clinical intervention?

Albuminuria predicts cardiovascular disease (CVD) events but it is likely to vary over time in a nonlinear fashion. The aim of this study was to estimate the potentially differing predictive effect of albuminuria on the risk of CVD or related death over time. Data were from a cohort study of 3505 predominately indigenous adults from remote communities in Queensland,Australia, 1999-2006. Cox Proportional Hazards model analysis of the predictive effects of urinary albumin creatinine ratio on the risk of CVD or CVD-related death was undertaken for incident and prevalent CVD. Analyses sequentially removed those who had a cardiovascular event or related death for the first year through to six years. The baseline prevalence of microalbuminuria was 21.2% and for macroalbuminuria 6.7%. The incidence of CVD was92 in13,812 person-years. Microalbuminuria predicted incident CVD with a Hazard Ratio (HR) of 3.0 (95% CI 1.83 - 4.96) and for macroalbuminuria HR 10.8 (95% CI 6.58 - 17.68) and for those with pre-existing CVD, HR 2.6 (95% CI 1.65 - 3.97) and HR 9.7 (95% CI 6.38 - 14.82) respectively. People with macroalbuminuria who survived the first three years had a crude HR of an incident cardiovascular event or death of 13.0 (95% CI 6.45 - 26.39) to a peak of 32.3 (95% CI 8.55 - 121.77) for those who survived the first five years. The hazard appeared to drop in the 6th year although this is based on small numbers.The first three years after finding macroalbuminuria provide a potential window opportunity to actively manage the risk of incident CVD before the risk elevates.