Dietary niacin intake and mortality outcomes in hypertensive populations: analysis from NHANES 2003-2016

The rising prevalence of hypertension underscores the urgent need for effective management strategies. While niacin-based medications and supplements have shown promise in improving outcomes among patients with hypertension, the impact of dietary niacin intake on prognosis remains an area requiring further investigation. Using data from the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2016, this study examined the association between dietary niacin intake and mortality risk among 13,237 individuals with hypertension. During a median follow-up of 103 months, 3,151 participants (23.80%) died from all causes, and 864 (7.89%) died from cardiovascular diseases. In multivariable-adjusted Cox proportional hazards models, dietary niacin intake was independently associated with a lower risk of both all-cause mortality (HR = 0.993, 95% CI: 0.986-1.000, p = 0.036) and cardiovascular mortality (HR = 0.984, 95% CI: 0.971-0.997, p = 0.017). Niacin intake was categorized into quartiles: Q1 (< 15.5 mg/day), Q2 (15.5-21.1 mg/day), Q3 (21.1-28.2 mg/day), and Q4 (> 28.2 mg/day). Cox regression analysis indicated that participants in the Q3 group had a significantly lower risk of all-cause mortality compared to those in Q1 (HR = 0.788, 95% CI: 0.657-0.944, p = 0.010). Moreover, restricted cubic spline (RCS) analysis revealed a U-shaped association between dietary niacin intake and all-cause mortality (P for nonlinearity = 0.016). These findings highlight the potential benefits of dietary niacin in reducing mortality risk among hypertensive individuals and suggest that moderate increases in dietary niacin intake may represent a feasible strategy for reducing mortality risk in this population.