Association of serum 25-hydroxyvitamin D concentrations with all-cause and cause-specific mortality among individuals with gout and hyperuricemia.

Background: We aimed to probe the association of serum 25-hydroxyvitamin D [25(OH)D] concentrations with all-cause and cause-specific mortality among patients with gout and hyperuricemia (HUA).

Methods: The study included 1169 gout patients and 7029 HUA patients from the National Health and Nutrition Examination Survey (NHANES) 2007-2018 and 2001-2018, respectively. The association between serum 25(OH)D and mortality was evaluated by Cox proportional hazard and restricted cubic spline models.

Results: Among participants with gout and HUA, the weighted mean concentrations of serum 25(OH)D were 71.49 ± 30.09 nmol/L and 64.81 ± 26.92 nmol/L, respectively. Vitamin D deficiency occurred in 29.68% of gout patients and 37.83% of HUA patients. During 6783 person-years of follow-up among gout patients, 248 all-cause deaths occurred, among which 76 died from cardiovascular disease (CVD) and 49 died from cancer. 1375 HUA patients were recorded for all-cause mortality during 59,859 person-years of follow-up, including 427 CVD deaths and 232 cancer deaths. After multifactorial adjustment, per one-unit increment in natural log-transformed 25(OH)D was associated with lower risk of 55% all-cause mortality and 61% CVD mortality among gout patients, and a 45% reduced risk of cancer mortality among HUA patients. Restricted cubic splines showed a U-shaped relationship with all-cause and CVD mortality among HUA patients, with inflection points of 72.7 nmol/L and 38.0 nmol/L, respectively. The results were robust in subgroup and sensitivity analyses.

Conclusions: Serum 25(OH)D was negatively linearly correlated with mortality among gout patients, whereas U-shaped correlated with mortality in HUA patients. These results indicate that adequate vitamin D status could prevent premature death.