摘要：Objectives. We estimated sodium intake, which is associated with elevated blood pressure, a major risk factor for cardiovascular disease, and assessed its association with related variables among New York City adults. Methods. In 2010 we conducted a cross-sectional, population-based survey of 1656 adults, the Heart Follow-Up Study, that collected self-reported health information, measured blood pressure, and obtained sodium, potassium, and creatinine values from 24-hour urine collections. Results. Mean daily sodium intake was 3239 milligrams per day; 81% of participants exceeded their recommended limit. Sodium intake was higher in non-Hispanic Blacks (3477 mg/d) and Hispanics (3395 mg/d) than in non-Hispanic Whites (3066 mg/d; both P < .05). Higher sodium intake was associated with higher blood pressure in adjusted models, and this association varied by race/ethnicity. Conclusions. Higher sodium intake among non-Hispanic Blacks and Hispanics than among Whites was not previously documented in population surveys relying on self-report. These results demonstrate the feasibility of 24-hour urine collection for the purposes of research, surveillance, and program evaluation. Cardiovascular disease (CVD) is the leading cause of death in the United States, 1 and hypertension is a leading risk factor. A positive and continuous relationship between sodium intake and blood pressure (BP) is well established. 2 Existing estimates of sodium intake measured by self-report show that US adults consume a daily average of 3400 milligrams, well above the recommended limit (1500–2300 mg/d), 2 and public health efforts are aimed at reducing sodium consumption. 3–5 In a simulation analysis of risk factor and outcome data from key CVD data sources, researchers estimated that up to 92 000 deaths could be averted annually by lowering the current mean adult intake by 1200 milligrams of sodium, resulting in intake closer to the recommended limit. 6 Although reduced sodium intake decreases BP on average in all racial/ethnic groups and in individuals with normal and high BP, the BP-lowering effect of sodium reduction is greater in Blacks than in other racial/ethnic groups. 7,8 National estimates of sodium intake derived from self-report do not demonstrate higher intake among Blacks. The gold standard method for assessing sodium intake is measurement of sodium excretion in rigorously collected 24-hour urine samples, although this method has some limitations, such as undercollection. 9 This method has been used to assess population intake in the United Kingdom, Finland, Portugal, and Barbados. 10–14 In the United States, population intake has been assessed since 1971 through 24-hour dietary recall. Although adequate for understanding general trends and intake, estimates that rely on self-report are subject to reporting error and bias. 9 Objective measures would avoid these problems; however, to date no representative assessment of sodium intake derived from 24-hour urine collections has been performed in the United States. In the absence of nationally representative US surveys employing the gold standard method, we measured sodium excretion in urine over 24 hours in a representative sample of adults in New York City. Our objectives were to estimate mean population sodium intake, overall and by subgroup, particularly in different racial/ethnic groups; to understand sodium intake in relation to recommended limits; and to assess the relationship between sodium intake and other variables.
