Use of Dietary Supplements Among People With Atherosclerotic Cardiovascular Disease in the United States: A Population-Based Analysis From NHANES

BACKGROUND

Dietary supplement use is prevalent in the general US population, but little is known regarding the driving reasons for their use among those with atherosclerotic cardiovascular disease (ASCVD).

METHODS AND RESULTS

Data from the National Health and Nutrition Examination Survey (NHANES) from 2017 to March 2020 were used to identify adults with ASCVD. Supplement use was assessed by interviewers using label review, and surveys captured self-reported reasons for use. Demographic, clinical, medication, and laboratory characteristics were compared between supplement users and nonusers. Among individuals with ASCVD in the National Health and Nutrition Examination Survey (n=965; mean age, 65 years; 56.1% men; 73.7% White individuals), 73.1% reported taking ≥1 dietary supplements, most commonly multivitamins (35.4%), vitamin D (30.8%), and fish oil (19.8%). Of those taking supplements, 47.3% report taking them under the advisement of a health professional. Nearly one fifth (17.9%) reported taking at least 1 supplement for "heart health," most commonly fish oil (11.1%), followed by CoQ10 (4.2%) and resveratrol (1.5%). Supplement users were older (68 versus 62 years; P=0.003), included more women (45.8% versus 37.7%; P=0.17), were less likely to smoke (11.0% versus 36.4%; P<0.001), had higher levels of education (P=0.005) and income (P<0.001), and higher use of statins (69.4% versus 55.8%; P=0.046).

CONCLUSIONS

Supplement use is common in people with ASCVD. Among the top 3 supplements, a substantial minority were being taken under the direction of health professionals. Supplement users often report taking supplements "for heart health," despite a lack of randomized trial evidence for benefit in ASCVD, indicating a need for more patient and clinician education regarding health benefits of dietary supplements in ASCVD.

Accuracy of incidental visual coronary artery calcium assessment compared with dedicated coronary artery calcium scoring

INTRODUCTION

CAC can be detected on routine chest computed tomography (CT) scans and may contribute to CVD risk estimation, but the accuracy of visual CAC scoring may be affected by the specialty of the interpreting radiologist and/or the use of contrast.

METHODS

The accuracy of visual CAC estimation on non-gated CT scans was evaluated at UT Southwestern Medical Center (UTSW) and Parkland Health and Hospital System (PHHS). All adults who underwent CAC scanning and a non-gated CT scan within 6 months were identified and the scores from the two CTs were compared overall and stratified by type of reader and whether contrast was used. Visual CAC categories of none, small, moderate, and large were compared to CAC ​= ​0, 1-99, 100-399, and ≥400, respectively.

RESULTS

From 2016 to 2021, 934 patients (mean age 60 ​± ​12 ​y, 43% male, 61% White, 34% Black, 24% Hispanic, 54% from PHHS) had both CT scans. Of these, 441 (47%) had no CAC, 278 (30%) small, 147 (16%) moderate, and 66 (7%) large CAC on non-gated CT. Visual CAC estimates were highly correlated with CAC scores (Kendalls tau-b ​= ​0.76, p ​< ​0.0001). Among those with no visual CAC, 76% had CAC ​= ​0 (72% of contrast-enhanced vs 85% of non-contrast scans, 88% of scans interpreted by CT radiologist vs 78% of those interpreted by other radiologist). In those with moderate-to-large visual CAC, 99% had CAC >0 and 88% had CAC ≥100, including 89% of those with contrast, 90% of those without contrast, 80% of those read by a CT radiologist, and 88% of those read by a non-CT radiologist.

DISCUSSION

Visual CAC estimates on non-gated CT scans are concordant with Agatston score categories from cardiac CT scans. A lack of visual CAC on non-gated CT scans may not be sufficient to "de-risk" patients, particularly for contrast-enhanced scans and those read by non-CT radiologists. However, the presence of moderate-to-large CAC, including on contrasted scans and regardless of radiologist type, is highly predictive of CAC and may be used to identify high-risk patients for prevention interventions.

Health Claims and Doses of Fish Oil Supplements in the US

Importance

One in 5 US adults older than 60 years takes fish oil supplements often for heart health despite multiple randomized clinical trials showing no data for cardiovascular benefit for supplement-range doses. Statements on the supplement labels may influence consumer beliefs about health benefits.

Objectives

To evaluate health claims made on the labels of fish oil supplements in the US, and to examine doses of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in commonly available formulations.

Design, Setting, and Participants

This cross-sectional study used data from labels of on-market fish oil (and nonfish ω-3 fatty acid) supplements obtained from the National Institutes of Health Dietary Supplement Label Database. The study was conducted and data analyzed from February to June 2022.

Main Outcome and Measures

The frequency and types of health claims made on fish oil labels (US Food and Drug Administration [FDA]-reviewed qualified health claim vs a structure/function claim) and the organ system referenced were evaluated. The total daily doses of combined EPA and DHA (EPA+DHA) were assessed for supplements from 16 leading manufacturers and retailers.

Results

Across 2819 unique fish oil supplements, 2082 (73.9%) made at least 1 health claim. Of these, only 399 (19.2%) used an FDA-approved qualified health claim; the rest (1683 [80.8%]) made only structure/function claims (eg, "promotes heart health"). Cardiovascular health claims were the most common (1747 [62.0%]). Across 16 leading brands/manufacturers, 255 fish oil supplements were identified. Among these, substantial variability was found in the daily dose of EPA (median [IQR], 340 [135-647] mg/d), DHA (median [IQR], 270 [140-500] mg/d), and total EPA+DHA (median [IQR], 600 [300-1100] mg/d). Only 24 of 255 supplements (9.4%) evaluated contained a daily dose of 2 g or more EPA+DHA.

Conclusions

Results of this cross-sectional study suggest that the majority of fish oil supplement labels make health claims, usually in the form of structure/function claims, that imply a health benefit across a variety of organ systems despite a lack of trial data showing efficacy. Significant heterogeneity exists in the daily dose of EPA+DHA in available supplements, leading to potential variability in safety and efficacy between supplements. Increasing regulation of dietary supplement labeling may be needed to prevent consumer misinformation.