TOPLINE:
High levels of serum uric acid (SUA) were significantly associated with a higher risk for all-cause mortality, but low levels were linked to a higher risk for both all-cause mortality and cardiovascular disease (CVD) mortality in adults with obstructive sleep apnea (OSA).
METHODOLOGY:
The researchers used data from four cycles of the National Health and Nutrition Examination Survey — 2005-2006, 2007-2008, 2015-2016, and 2017-2018; the study population included 5584 individuals with OSA.
The primary outcomes were all-cause mortality and CVD mortality, and the researchers used a restricted cubic splines (RCS) model to assess the relationships between SUA and mortality.
Measures of SUA were divided into quintiles: Q1 (<4.4 mg/dL), Q2 (4.4-5.2 mg/dL), Q3 (5.2-5.899 mg/dL), Q4 (5.9-6.79 mg/dL), and Q5 (≥6.8 mg/dL); Q4 served as the reference.
TAKEAWAY:
A total of 537 deaths occurred in the study population; 108 of these were attributed to CVD.
The adjusted hazard ratios for SUA quintiles Q1, Q2, Q3, Q4, and Q5 for all-cause mortality were 1.33, 1.53, 1.18, 1.00 (reference), and 1.51, respectively (P = .03 for trend) and for CVD mortality were 1.12, 2.40, 1.45, 1.00 (reference), and 1.77, respectively (P = .98 for trend).
Using the RCS model, the researchers found a U-shaped association between SUA and all-cause mortality overall; the inflection point was 5.83 mg/dL, and the association was consistent across subgroups.
