OP98 Formulas to estimate dietary sodium intake from spot urine are associated with CVD risk and mortality independently of sodium concentration
Bibliographic record
Abstract
<h3>Background</h3> Numerous cohort studies with sodium intake measured by gold standard method (i.e. non-consecutive 24h urinary sodium excretion) identified a positive linear association of sodium intake with cardiovascular disease (CVD) risk. However, several studies using formulas to estimate sodium intake from spot urine reported opposite findings. We aim to evaluate whether and how these formulas lead to these different findings. <h3>Methods</h3> UK Biobank is a prospective cohort study with over 500,000 participants aged 40-69 years in the UK recruited during 2006-2010 and followed up. Random spot urine samples were collected and sodium concentration was measured. Sodium intake was estimated by INTERSALT, Kawasaki, and Tanaka formulas, respectively. The primary outcomes included CVD events and deaths. Hazard ratios (HRs) were estimated by Cox proportional-hazard model adjusted for multiple covariates. Quartiles and penalised splines of estimated sodium intakes were assessed to test both linear and non-linear relationships. We also fixed the sodium concentration with sex-specific mean and re-ran the above-mentioned analyses to assess whether and how formulas themselves impacted these associations. All analyses were performed on R v4.2.2. <h3>Results</h3> 435,336 participants were included. 44,268 CVD events and 3,251 CVD deaths occurred during a median follow-up of 12 years. The mean estimated sodium intake was 142.5 (SD=34.6), 178.17 (51.75), and 146.88 (32.79) mmol/day from INTERSALT, Kawasaki and Tanaka formulas. For CVD incidence, linear inverse associations were observed for INTERSALT and Tanaka estimates (HRs [95% CIs]: 0.9 [0.83, 0.97] and 0.93 [0.89, 0.97] for every 50 mmol reduction in estimated daily sodium intake; P-linear=0.0047 and 0.0021), and U-shape association for Kawasaki (P-nonlinear=0.0026). When the sodium concentration term was fixed in the formulas, inverse association was seen for all formulas (HRs [95% CIs]: 0.86 [0.77, 0.95], 0.96 [0.93, 0.99] and 0.94 [0.89, 0.99] for INTERSALT, Kawasaki and Tanaka; P-linear=0.0054, 0.0166 and 0.0188). For CVD mortality, no association was observed for any formula, but a non-linear association for INTERSALT after fixing the sodium concentration term (P-nonlinear=0.0287). <h3>Conclusion</h3> A nonlinear or inverse linear association with CVD incidence was found for formula estimates of sodium intake, and no association was found with CVD mortality. The observed relationships were problematic as formulas were associated with outcomes independently of sodium concentration. Formulas to estimate sodium intake from spot urine samples should not be used in research investigating associations of sodium intake with CVD outcomes, as they are associated with the controversy of benefits from sodium reduction and may hinder implementation of relevant policies.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".