Background/Purpose: High sodium intake has been reported to be associated with increased ACPA positivity in smoker RA patients. However, apart from this, the associations with high sodium intake in the general population, elevation in blood pressure, endothelial dysfunction, albuminuria and cardiovascular (CV) morbidity and mortality, have not been examined in RA patients before. In this study, we assessed the association between sodium intake and subclinical atherosclerosis identified by the carotid ultrasound (US), in RA patients.

Methods: RA patients without any CV disease, diabetes, chronic kidney disease, or who were not on diuretic treatment were included. To estimate dietary sodium intake, sodium excretion in 24h urine samples were determined. High sodium intake was defined as >200mmol/day (>12g/day) sodium in 24h urine. Carotid US findings of carotid intima-media thickness (cIMT) > 0.90 mm and/or carotid plaques were regarded as subclinical atherosclerosis. Along with disease characteristics, traditional CV risk factors, DAS28 scores, ESR and CRP values of each visit during the entire followup were recorded. Average DAS28, ESR, and CRP were calculated. Multivariable logistic regression was used to adjust for RA severity measures and other CV risk factors influencing atherosclerosis.

Results: Of the 110 RA patients (F/M=89/21, age 54±11 years, disease duration 14±7 years, hypertension 27.3%) 24 (21.8%) had subclinical atherosclerosis (cIMT>0.90 mm: 14 patients, plaques: 20 patients). The mean daily sodium excretion was 189.2±72.9 mmol/day, equal to a sodium intake of 11.1±4.3g/day. Overall, 48 (44%) patients had high sodium intake (mean 15.1±2.8g/day). Sodium intake 14.8±4.5g/day vs 10.1±3.7g/day (P<0.001), and % of high sodium consumers 66.7% vs 37.2 % (P=0.010) were significantly higher in patients with subclinical atherosclerosis. Daily sodium intake was positively correlated with cIMT (r=0.32, P=0.001), average ESR (r=0.22, P=0.024) and CRP (r=0.29, P=0.003), and serum uric acid levels (r=0.27, P=0.005). There was a nonsignificant positive correlation between systolic and diastolic blood pressures and sodium intake. Sodium intake in NSAID or glucocorticoid using RA patients was similar to non-users. Similarly, hypertensive, obese, smoker or seropositive patients’ sodium intake was not higher. When disease characteristics, cumulative disease activity, and traditional CV risk factors were adjusted by using multivariable logistic regression analysis, sodium intake was found to be associated with subclinical atherosclerosis in RA patients (OR=1.46, 95% CI, 1.11-1.90, P=0.006).

Conclusion: Higher sodium intake is associated with subclinical atherosclerosis in RA patients. These preliminary results should be confirmed in a larger sample. Considering the high CVD risk in RA patients, further investigation is needed to determine whether high sodium intake is associated with inflammation, CV morbidity and mortality, and other comorbid conditions such as hypertension in RA. As recommended for the hypertensive adult population, sodium intake reduction may be considered in RA patients, particularly in hypertensive and high CV risk patients.

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/association-between-high-sodium-intake-and-subclinical-atherosclerosis-in-patients-with-rheumatoid-arthritis/