Vitamin E and risk of age-related cataract: a meta-analysis

Abstract

Objective: We conducted a meta-analysis to evaluate the relationship between vitamin E and age-related cataract (ARC). Design: The fixed-or random-effect model was selected based on heterogeneity. Meta-regression was used to explore potential sources of between-study heterogeneity. Publication bias was evaluated using Begg's test. The dose-response relationship was assessed by a restricted cubic spline model. Setting: Relevant studies were identified by a search of PubMed and the Cochrane Library to May 2014, without language restrictions. Subjects: Studies involved samples of people of all ages. Results: Dietary vitamin E intake, dietary and supplemental vitamin E intake, and high serum tocopherol levels were significantly associated with decreased risk of ARC, the pooled relative risk was 0·73 (95 % CI 0·58, 0·92), 0·86 (95 % CI 0·75, 0·99) and 0·77 (95 % CI 0·66, 0·91), respectively. Supplemental vitamin E intake was non-significantly associated with ARC risk (relative risk = 0·92; 95 % CI 0·78, 1·07). The findings from dose-response analysis showed evidence of a non-linear association between dietary vitamin E intake and ARC. The risk of ARC decreased with dietary vitamin E intake from 7 mg/d (relative risk = 0·94; 95 % CI 0·90, 0·97). Conclusions: The findings of the meta-analysis indicated that dietary vitamin E intake, dietary and supplemental vitamin E intake, and high level of serum tocopherol might be significantly associated with reduced ARC risk.

Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses

“…Dietary vitamin E intake was related to ARC and PD in addition to health outcomes related to cancer. It had a strong correlation with a lower incidence of ARC [29]. Etminan et al discovered that vitamin E consumption in the diet protects against PD [40].…”

“…Similarly, except for ovarian cancer, all other cancers included were inversely associated with total vitamin E intake, including glioma [41], pancreatic cancer [42], and bladder cancer [21]. A lower incidence of both cancer and ARC was strongly associated with total vitamin E consumption [29]. All of the health outcomes used a binary variable, with RR as the effect metrics (Figure 2D).…”

“…Circulating α-tocopherol’s results are shown in Figure 2E,F. Seven meta-analyses examined the association between circulating α-tocopherol levels and health outcomes, including ARC [29], asthma or wheeze in children [27], bladder cancer [21], cardiovascular mortality [15], colorectal cancer [43], CVD [44], and prostate cancer [45]. Except that circulating α-tocopherol levels did not significantly reduce the risk of CVD, there was a protective association between circulating α-tocopherol levels and the remaining six health outcomes.…”

Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses

“…Dietary vitamin E intake was related to ARC and PD in addition to health outcomes related to cancer. It had a strong correlation with a lower incidence of ARC [29]. Etminan et al discovered that vitamin E consumption in the diet protects against PD [40].…”

“…Similarly, except for ovarian cancer, all other cancers included were inversely associated with total vitamin E intake, including glioma [41], pancreatic cancer [42], and bladder cancer [21]. A lower incidence of both cancer and ARC was strongly associated with total vitamin E consumption [29]. All of the health outcomes used a binary variable, with RR as the effect metrics (Figure 2D).…”

“…Circulating α-tocopherol’s results are shown in Figure 2E,F. Seven meta-analyses examined the association between circulating α-tocopherol levels and health outcomes, including ARC [29], asthma or wheeze in children [27], bladder cancer [21], cardiovascular mortality [15], colorectal cancer [43], CVD [44], and prostate cancer [45]. Except that circulating α-tocopherol levels did not significantly reduce the risk of CVD, there was a protective association between circulating α-tocopherol levels and the remaining six health outcomes.…”

Influence of Diet, Dietary Products and Vitamins on Age-Related Cataract Incidence: A Systematic Review

“…Starting from 7 mg of vitamin E per day, a statistically significant decreased risk of developing ARC was observed, with even higher results for the increasing vitamin E daily dosage (RR 7mg/d = 0.94, 95%CI = 0.90–0.97; RR 8mg/d = 0.89, 95%CI = 0.85–0.94; RR 9mg/d = 0.80, 95%CI = 0.74–0.88 and RR 10mg/d = 0.69, 95%CI = 0.59–0.80). Ten studies, encompassing 358,007 participants, did not show any significant association between supplementary vitamin E intake and the risk of ARC [33]. This is confirmed by Jiang’s study, in which the analysis of RCTs on vitamin E supplementation compared with the placebo exhibited no significant protective effect against ARC (RR = 0.97, 95%CI = 0.91–1.03, p = 0.262; RR = 0.99, 95%CI = 0.92–1.07, p = 0.820, respectively) [32].…”

“…Furthermore, the multivariable-adjusted hazard ratios for male participants who took other supplements in addition to vitamin E, compared to those calculated for non-supplement-users, were also associated with a higher risk of cataracts (HR = 1.02, 95%CI = 0.87–1.20) [36]. However, a comparison of the highest and the lowest combined dietary and supplementary vitamin E intake still proved an inverse association with ARC risk (RR = 0.86; 95%CI = 0.75–0.99; I 2 = 47.1%; p heterogeneity = 0.129) [33].…”

Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses

“…Dietary vitamin E intake was related to ARC and PD in addition to health outcomes related to cancer. It had a strong correlation with a lower incidence of ARC [29]. Etminan et al discovered that vitamin E consumption in the diet protects against PD [40].…”

“…Similarly, except for ovarian cancer, all other cancers included were inversely associated with total vitamin E intake, including glioma [41], pancreatic cancer [42], and bladder cancer [21]. A lower incidence of both cancer and ARC was strongly associated with total vitamin E consumption [29]. All of the health outcomes used a binary variable, with RR as the effect metrics (Figure 2D).…”

“…Circulating α-tocopherol’s results are shown in Figure 2E,F. Seven meta-analyses examined the association between circulating α-tocopherol levels and health outcomes, including ARC [29], asthma or wheeze in children [27], bladder cancer [21], cardiovascular mortality [15], colorectal cancer [43], CVD [44], and prostate cancer [45]. Except that circulating α-tocopherol levels did not significantly reduce the risk of CVD, there was a protective association between circulating α-tocopherol levels and the remaining six health outcomes.…”

Influence of Diet, Dietary Products and Vitamins on Age-Related Cataract Incidence: A Systematic Review

“…Starting from 7 mg of vitamin E per day, a statistically significant decreased risk of developing ARC was observed, with even higher results for the increasing vitamin E daily dosage (RR 7mg/d = 0.94, 95%CI = 0.90–0.97; RR 8mg/d = 0.89, 95%CI = 0.85–0.94; RR 9mg/d = 0.80, 95%CI = 0.74–0.88 and RR 10mg/d = 0.69, 95%CI = 0.59–0.80). Ten studies, encompassing 358,007 participants, did not show any significant association between supplementary vitamin E intake and the risk of ARC [33]. This is confirmed by Jiang’s study, in which the analysis of RCTs on vitamin E supplementation compared with the placebo exhibited no significant protective effect against ARC (RR = 0.97, 95%CI = 0.91–1.03, p = 0.262; RR = 0.99, 95%CI = 0.92–1.07, p = 0.820, respectively) [32].…”

“…Furthermore, the multivariable-adjusted hazard ratios for male participants who took other supplements in addition to vitamin E, compared to those calculated for non-supplement-users, were also associated with a higher risk of cataracts (HR = 1.02, 95%CI = 0.87–1.20) [36]. However, a comparison of the highest and the lowest combined dietary and supplementary vitamin E intake still proved an inverse association with ARC risk (RR = 0.86; 95%CI = 0.75–0.99; I 2 = 47.1%; p heterogeneity = 0.129) [33].…”

Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses

“…Dietary vitamin E intake was related to ARC and PD in addition to health outcomes related to cancer. It had a strong correlation with a lower incidence of ARC [29]. Etminan et al discovered that vitamin E consumption in the diet protects against PD [40].…”

“…Similarly, except for ovarian cancer, all other cancers included were inversely associated with total vitamin E intake, including glioma [41], pancreatic cancer [42], and bladder cancer [21]. A lower incidence of both cancer and ARC was strongly associated with total vitamin E consumption [29]. All of the health outcomes used a binary variable, with RR as the effect metrics (Figure 2D).…”

“…Circulating α-tocopherol’s results are shown in Figure 2E,F. Seven meta-analyses examined the association between circulating α-tocopherol levels and health outcomes, including ARC [29], asthma or wheeze in children [27], bladder cancer [21], cardiovascular mortality [15], colorectal cancer [43], CVD [44], and prostate cancer [45]. Except that circulating α-tocopherol levels did not significantly reduce the risk of CVD, there was a protective association between circulating α-tocopherol levels and the remaining six health outcomes.…”

Influence of Diet, Dietary Products and Vitamins on Age-Related Cataract Incidence: A Systematic Review

“…Starting from 7 mg of vitamin E per day, a statistically significant decreased risk of developing ARC was observed, with even higher results for the increasing vitamin E daily dosage (RR 7mg/d = 0.94, 95%CI = 0.90–0.97; RR 8mg/d = 0.89, 95%CI = 0.85–0.94; RR 9mg/d = 0.80, 95%CI = 0.74–0.88 and RR 10mg/d = 0.69, 95%CI = 0.59–0.80). Ten studies, encompassing 358,007 participants, did not show any significant association between supplementary vitamin E intake and the risk of ARC [33]. This is confirmed by Jiang’s study, in which the analysis of RCTs on vitamin E supplementation compared with the placebo exhibited no significant protective effect against ARC (RR = 0.97, 95%CI = 0.91–1.03, p = 0.262; RR = 0.99, 95%CI = 0.92–1.07, p = 0.820, respectively) [32].…”

“…Furthermore, the multivariable-adjusted hazard ratios for male participants who took other supplements in addition to vitamin E, compared to those calculated for non-supplement-users, were also associated with a higher risk of cataracts (HR = 1.02, 95%CI = 0.87–1.20) [36]. However, a comparison of the highest and the lowest combined dietary and supplementary vitamin E intake still proved an inverse association with ARC risk (RR = 0.86; 95%CI = 0.75–0.99; I 2 = 47.1%; p heterogeneity = 0.129) [33].…”