Association between serum 25-hydroxyvitamin D and vitamin D dietary supplementation and risk of all-cause and cardiovascular mortality among adults with hypertension
Abstract
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Background
The relationship between vitamin D status and mortality among adults with hypertension remains unclear.
Methods
This prospective cohort study involved a sample of 19,500 adults with hypertension who participated in the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018. We utilized a weighted COX proportional hazard model to assess the association between vitamin D status and mortality. This statistical model calculates hazard ratios (HR) and their corresponding 95% confidence intervals (95% CI).
Results
The study indicated that lower serum 25(OH)D concentration was associated with an increased risk of all-cause mortality among individuals with hypertension. Specially. Those with concentrations between 25.0 and 49.9 nmol/L (HR = 1.71, 95%CI = 1.22–2.40) and less than 25.0 nmol/L (HR = 1.97, 95%CI = 1.15–3.39) had higher hazard ratios for all-cause mortality. Individuals with hypertension who took vitamin D supplements had a lower risk of all-cause mortality, but not the risk of CVD mortality (HR 0.75, 95%CI 0.54–1.03), compared to those who did not supplement (HR = 0.76, 95%CI = 0.61–0.94). Subgroup analysis further revealed that vitamin D supplementation was associated with a reduced risk of all-cause mortality among individuals without diabetes (HR = 0.65, 95%CI = 0.52–0.81) and individuals without CVD (HR = 0.75, 95%CI = 0.58–0.97), and a decreased risk of CVD mortality among individuals without diabetes (HR = 0.63, 95%CI = 0.45–0.88) and without CVD (HR = 0.61, 95%CI = 0.40–0.92). Furthermore, higher-dose vitamin D supplementation was also associated with a greater reduction in all-cause mortality among hypertensive individuals, and there was the potential synergistic effect of combining normal-dose calcium and vitamin D supplementation, showing a superior effect on mortality compared to low-dose supplementation in adults with hypertension.
Conclusions
This prospective cohort study demonstrated a significant association between lower serum 25 (OH)D concentration and increased all-cause mortality among adults with hypertension. Furthermore, the study found that vitamin D supplementation had a strong and significantly positive correlation with reduced all-cause and CVD mortality among hypertensive individuals without diabetes or CVD. This positive correlation suggests that vitamin D supplementation could potentially be an effective strategy to reduce the risk of mortality in this specific group of people.
Introduction
According to recent statistics, it was found that by 2019, approximately 52% of women and 43% of men worldwide had been diagnosed with hypertension [1, 2]. Despite improvements in diet and modern lifestyles, the prevalence of hypertension continues to rise, even affecting younger individuals [1,2,3]. This persistent and poorly controlled hypertension poses significant risks for cardiovascular disease and mortality, with impacts such as increased cardiac workload, vascular damage, blood clot formation, aneurysm development, and cerebrovascular events [4].
Serum 25-hydroxyvitamin D [25 (OH)D], which includes both 25 (OH)D2 and 25 (OH)D3, is the main form of vitamin D in the bloodstream and is used as an indicator to assess vitamin D levels [5]. Vitamin D deficiency is widespread, and the use of vitamin D supplements has become increasingly common [6,7,8]. Observational studies have shown that higher concentrations of serum 25 (OH)D are associated with a reduced blood pressure, lower risk of cardiovascular disease (CVD) and all-cause mortality in adults [9,10,11,12,13,14]. The presence of specific vitamin D receptors in cardiovascular tissue in basic experimental studies suggests a direct role of vitamin D in maintaining cardiovascular function [15]. Given the association between vitamin D and hypertension and CVD-related deaths, it is important to determine whether vitamin D is associated with mortality in hypertension, and whether the use of vitamin D supplements can improve mortality in hypertensive individuals. Nanri A et al. conducted a study on the correlation between dietary vitamin D intake and mortality in the Japanese and suggested that higher dietary vitamin D could reduce the risk of mortality in hypertension [16].In addition, the Honolulu Heart Program study found a significant association between low dietary vitamin D intake and higher overall mortality during 45 years of follow-up among middle-aged Japanese American men with hypertension, but not in those without hypertension [17]. Both studies indicate that higher dietary vitamin D intake is associated with lower mortality in individual with hypertension. Vitamin D supplements can provide more vitamin D than dietary intake, so whether additional vitamin D supplements can reduce mortality in individuals with hypertension. However, no studies have investigated the association between vitamin D supplementation and mortality in individual with hypertension.
Therefore, our objective is to investigate and analyze the association between serum 25 (OH)D levels, vitamin D supplementation, and mortality in adults with hypertension. This research aims to provide valuable insights and references for preventing mortality in adults with hypertension and determining the potential benefits of vitamin D supplements in this population.
- Haowen Ye,
- Yexin Li,
- Shaomin Liu,
- Xiaofang Zhang,
- Huanzhu Liang,
- Ying Wang,
- Ruxin Wang,
- Han Liu,
- Yun Wen,
- Chunxia Jing &
- Lihong Wang
Nutrition Journal volume 23, Article number: 33 (2024) Cite this article
