Are low blood urate levels linked to a higher risk of premature death? Summary Aim Whether low serum urate (UA) levels contribute to adverse outcomes remains controversial. We evaluated the relationship between low AU and sarcopenia, and evaluated whether sarcopenia confounds the associations between low AU and mortality. Methods We used data from the National Health and Nutrition Examination Survey (1999-2006). Participants with available whole-body dual-energy absorptiometry body composition measurements and UA concentrations were included. Body composition assessments included BMI, waist circumference, lifetime maximum BMI, as well as age-, sex-, and race-specific appendicular lean mass index (ALMI) and fat mass index (FMI). . ALMIFMI Z scores represent ALMI relative to FMI. We evaluated associations between UA and body composition using logistic regression. Associations between SU and mortality were assessed before and after adjusting for differences in body composition using Cox regression. Results Among 13,979 participants, low UA concentrations (<2.5 mg/dL in women; <3.5 mg/dL in men) were associated with low lean mass (ALMI and ALMIFMI Z scores), BMI below of normal weight (<18.5 kg/m2), and higher rates of weight loss. The proportion of patients with low ALMI Z scores was 29% in the low AU group versus 16% in the normal AU group (p = 0.001). Low UA was associated with higher mortality before adjusting for body composition (HR (95% CI): 1.61 [1.14,2.28], p=0.008), but was attenuated and not significant after adjustment for body composition and weight loss (HR: 1.30 [0.92, 1.85], p=0.13). Conclusions Sarcopenia and weight loss are more common among those with low uric acid concentrations. Differences in body composition may help explain associations between low UA and higher mortality. |
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New research published in Arthritis & Rheumatology suggests that adults with low levels of urate in the blood, a breakdown product of metabolism, may be at increased risk for low skeletal muscle mass and strength and may face a higher risk of death. early.
The study used data from 1999–2006 from the National Health and Nutrition Examination Survey. Among 13,979 participants aged 20 years or older, low blood urate concentrations were associated with low lean mass, underweight body mass index, and higher rates of weight loss.
Low blood urate was associated with a 61% increased risk of death (through 2015) before adjusting for body composition, but the risk was not significant after adjusting for body composition and weight loss.
"These observations support what many have intuited, namely that people with low serum urate levels have higher mortality and worse outcomes not because low urate is bad for health, but because low urate levels tend to occur among sicker people, who have lost weight and have adverse body composition ,” said lead author Joshua F. Baker, MD, MSCE, of the University of Pennsylvania. "While this observational study does not refute a causal association, it does suggest that great care is needed when interpreting epidemiological associations between urate levels and health outcomes."
