Trends in 24-h urinary sodium excretion in the United States 1957–2003: a systematic review

摘要

>Background: Few studies have examined temporal trends in sodium intake in the US population. Collections of 24-h urine sodium excretions are reliable markers for dietary sodium intake.>Objective: We examined temporal trends in 24-h urine sodium excretions to estimate temporal trends in sodium intake in the US population.>Design: We performed a systematic search of English-language articles in MEDLINE for studies that reported collections of 24-h urine sodium excretions in the United States. We estimated mean urine sodium excretions over time for all studies and demographic subgroups.>Results: We analyzed 38 studies, which dated from 1957 to 2003, and estimated a mean (±SE) 24-h urine sodium excretion per person of 3526 ± 75 mg Na. In a multivariate random-effects model with study year, sex, age, and race, the study year was not associated with any significant change in sodium excretions (coefficient = 154 mg Na · 24 h⁻¹ · 10 y⁻¹; 95% CI: −140, 448 mg Na · 24 h⁻¹ · 10 y⁻¹). In subgroup analyses, there was no significant temporal trend seen in male, female, black, or white study participants.>Conclusion: Sodium intake in the US adult population appears to be well above current guidelines and does not appear to have decreased with time.