Mortality Links to eGFR and Albuminuria Are Stronger in Women

 

Lower eGFR and higher albuminuria carry increased risks of death and renal failure in both sexes, but the magnitude of the associations is greater in women, reports a study in the British Medical Journal.

The meta-analysis by the Chronic Kidney Disease Prognosis Consortium used data on more than 2 million members of 46 cohorts. The data included nearly 1.9 million participants from general population cohorts, plus approximately 150,000 participants from high-risk cohorts and 37,000 from CKD cohorts. In addition to deaths or ESRD events, the studies included information on eGFR and urinary albumin-creatinine ratio.

In all eGFR and albumin-creatinine strata, all-cause and cardiovascular mortality were higher in men than women. For both sexes, lower eGFR and higher albumin-creatinine ratio were associated with a higher risk of death.

However, the slope of the associations for mortality was steeper for women. At an eGFR of 45 mL/min/1.73 m2, adjusted hazard ratios (HRs) for all-cause mortality were 1.32 in women versus 1.22 for men (compared to eGFR of 95). At a urinary albumin-creatinine ratio of 30 mg/g, HRs were 1.69 for women and 1.43 for men (compared to a ratio of 5). The interactions by sex were significant for mortality; there was no such pattern for ESRD.

It has been unclear whether the adverse outcome risks associated with eGFR and albuminuria in CKD are modified by sex. This large meta-analysis confirms that lower eGFR and higher albuminuria increase the risk of death for both sexes.

However, the slopes of the associations with eGFR and albumin-creatinine ratio are steeper for women. Especially given the lower incidence of starting dialysis in women, the researchers write, “Low estimated glomerular filtration rate or albuminuria should be considered at least as potent a risk factor in women as it is in men” [Nitsch D, et al:Associations of estimated glomerular filtration rate and albuminuria with mortality and renal failure by sex: a meta-analysis. BMJ 2013; 346: f324].


April 2013 (Vol. 5, Number 4)