Silent Monosodium Urate Crystal Deposits Are Associated With Severe Coronary Calcification in Asymptomatic Hyperuricemia: An Exploratory Study

Abstract

Objective. To evaluate the association between monosodium urate (MSU) crystal deposits in patients with asymptomatic hyperuricemia and the severity and extension of coronary artery disease (CAD).Methods. In this cross-sectional study, consecutive inpatients with a non-ST elevation acute coronary event and asymptomatic hyperuricemia (serum uric acid concentration of ‡7.0 mg/dl) or normouricemia (serum uric acid concentration of <7.0 mg/dl) were enrolled. In patients with asymptomatic hyperuricemia, the presence of MSU crystals was determined by ultrasound evaluation of both knees and first metatarsophalangeal joints and by compensated polarized light microscopy. CAD was assessed by coronary angiography, and the following variables were considered: 1) the presence of moderate-to-severe coronary artery calcification, 2) the number of significant coronary stenoses, and 3) the presence of multivessel disease. The association between variables indicating the severity of CAD and the presence of MSU crystals was analyzed by multivariate regression.Results. One hundred forty patients were enrolled. After ultrasonography and microscopic analyses were performed, the patients were classified as having normouricemia (n 5 66), asymptomatic hyperuricemia alone (n 5 61), and asymptomatic hyperuricemia with MSU crystals (n 5 13). The prevalence of moderate-to-severe coronary calcification was significantly higher in the patients with asymptomatic hyperuricemia with MSU crystals compared with patients with asymptomatic hyperuricemia alone and patients with normouricemia (P 5 0.003). An independent association was observed between the presence of moderateto-severe calcification and asymptomatic hyperuricemia with crystals (odds ratio 16.8, P 5 0.002). No significant association was observed for the other variables.Conclusion. Silent deposition of MSU crystals in patients with asymptomatic hyperuricemia was associated with more severe coronary calcification, which suggests more severe CAD in relation to crystal deposition.Gout is a disease characterized by deposition of monosodium urate (MSU) crystals (1). The hallmark clinical presentation is recurrent acute monoarthritis separated by long asymptomatic periods; in some cases, prominent accumulations of MSU crystals known as tophi develop. MSU crystals form and deposit when serum uric acid levels in body fluids are above the solubility limit (;7 mg/dl); this cutoff level has been used to define asymptomatic hyperuricemia in the absence of gouty manifestations, although other definitions have been used depending on the approach of the investiga-

Monosodium urate crystal deposition associated with the progress of radiographic grade at the sacroiliac joint in axial SpA: a dual-energy CT study

“…The sensitivity and specificity of DECT for gout were only 0.87 and 0.84 [18], because the deposition of MSU crystal is a necessary but not a sufficient condition. Besides, DECT MSU crystal deposition was observed in both multiple joints and soft tissues in patients with asymptomatic hyperuricaemia, and was associated with increasingly severe coronary calcification [19, 20]. In addition, our study found a large quantity of MSU crystal deposition with DECT in AxSpA patients without coexisting gout, according to the 1977 American Rheumatism Association classification criteria [21].…”

Relationship between serum urate concentration and clinically evident incident gout: an individual participant data analysis

“…This study did not include other endpoints associated with hyperuricaemia, such as hypertension,14 chronic kidney disease15 or cardiovascular disease,16 and consideration of these conditions may also be of relevance when counselling people with elevated serum urate concentrations. The study addressed clinically evident gout as an outcome and was not able to examine the influence of subclinical monosodium urate (MSU) crystal deposition, which is commonly present in people with asymptomatic hyperuricaemia17 18 and is associated with more severe coronary artery disease19; future prospective studies including advanced imaging methods such as ultrasound or dual-energy CT will be instructive to address this issue.…”

Cardiovascular risk of patients with gout seen at rheumatology clinics following a structured assessment

“…The new European League Against Rheumatism recommendations indicate the expedience of treating from the time of diagnosis to avoid further gout attacks and growing crystal load and to possibly prevent CV events 5. We recently found that patients with asymptomatic hyperuricemia with silent MSU deposits suffered from a more severe form of coronary atherosclerosis 6. The possibility that the CV risk in patients with gout may be higher than what is shown by the standard evaluation scores remains an open question, and the rationale for early and effective treatment for gout largely depends on its CV consequences.…”