Background/Purpose: Several studies have shown the relationship between gout and increased cardiovascular risk and mortality. Hyperuricemia and crystal-induced synovitis are associated with endothelial dysfunction and patients with gout may be at increased risk of early atherosclerosis. Many reports have indicated that endothelial dysfunction plays a key role in affecting cardiovascular and renal function. The flow-mediated dilation (FMD) test is the most commonly used non-invasive assessment of vascular endothelial function and is associated with an increased risk of vascular events. There is a lack of studies with FMD assessment in patients with gout.

Methods: Prospective cohort study with collection of demographic and clinical data and cardiovascular treatments received. BMI, serum uric acid, ESR, high-sensitivity CRP [hsCRP], ferritin, cholesterol, triglycerides, vitamin D and homocysteine were measured. Patients were referred to Vascular Surgery Department for flow-mediated dilation assessment with high-resolution two-dimensional ultrasound imaging of the brachial artery. Endothelial dysfunction was defined as pathological values of FMD below 10 (severe if less than 5). All patients met the ACR classification criteria for gout.

Results: One hundred and fifty patients, 97% men and 3% women. Average age: at time of study 56 (23-92); at diagnosis 47 years (15-79); at symptoms onset 45 years (15-77). 22.5% had tophi, 11.3% urate kidney stones, 42% gout family history, 41% cardiovascular disease family history. Hypertension 47.3%; diabetes mellitus 4.6%; dyslipidemia 56.7%; smokers 20.6%, quitters 37.6%; 75% overweight/obesity, mean BMI 28 (19-40). One patient had suffered stroke; 4 thrombosis; 17 ischemic heart disease (11 angina, 6 myocardial infarction). Analytical parameters: ESR 10 mm/h (1-68), hs-CRP 2.7 mg/dL (0.1-57.7); serum uric acid 6.9 mg/dL (2.4-11.8); ferritin 259 ng/ml (11-2000); cholesterol: 187 mg/dL (102-321), triglycerides 145 mg/dL (53-603); vitamin D 24.7 ng/mL (5.6-23.6; 29% <20); homocysteine 24.7 mmol/L (4-40; 32% >15 mmol/L). FMD was assessed in 147 patients with a mean value of -0,60 ± 0,52. The 81% of subjects showed pathological values indicating endothelial dysfunction, severe in 52%. In the multivariate analysis, the only analytical determinant of endothelial dysfunction was the serum vitamin D concentration, which showed a negative correlation with FMD.

Conclusion: There is a high prevalence of traditional cardiovascular risk factors and cardiovascular diseases in our cohort. Most of our patients with gout have endothelial dysfunction measured by FMD, and that is severe in more than a half of them. Vitamin D deficiency is common and correlates with pathological values of FMD in gout. Cardiovascular risk should be periodically assessed in gout and we will continue studying the potential value of FMD as a marker of endothelial dysfunction in patients with this rheumatic disease.

« Back to 2017 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/flow-mediated-dilation-as-a-marker-of-endothelial-dysfunction-in-gout/