Multivitamin use not found to be associated with mortality benefit at 20 years follow-up

by Alex Chan — July 6, 2024 in Cardiology, Chronic Disease, Gastroenterology
Reading Time: 2 mins read

1. In a cohort of healthy adults, multivitamin use was not associated with lower mortality risk at 20 years follow-up.

Evidence Rating Level: 2 (Good)

Approximately one-third of adults in the United States (US) use multivitamins (MV) to maintain or improve health and prevent chronic disease. However, the association between MV use and mortality have been mixed. This cohort study evaluated how self-reported daily MV use was associated with mortality risk in generally healthy adults. Data from three prospective cohort studies in the United States, with follow-up periods of over 20 years were analyzed. Analyses were performed for the first 12 years of follow-up (follow-up period 1 (FP1)) and the last 15 years of follow-up (follow-up period 2 (FP2)). Among 390,124 participants without a history of major chronic diseases (median [IQR] age, 61.5 [56.7-66.0] years; 21,6202 [55.4%] male), there was no association between MV use and lower all-cause mortality risk in FP1 (multivariable-adjusted hazard ratios (HRs) 1.04; 95% CI, 1.02-1.07), nor FP2 (multivariable-adjusted HR, 1.04; 95% CI, 0.99-1.08). In contrast, daily MV users had a 4% higher mortality risk than nonusers (FP1: HR, 1.04; 95% CI, 1.02-1.07; FP2: HR, 1.04; 95% CI, 0.99-1.08). Although this study did not find regular MV use among US adults to improve longevity, the authors did not rule out the possibility that daily MV use may relate to other health outcomes associated with aging. Overall however, study findings suggest that there is no long term mortality benefit associated with multivitamin use.

June 26, 2024

Multivitamin Use and Mortality Risk in 3 Prospective US Cohorts

Erikka Loftfield, PhD, MPH1; Caitlin P. O’Connell, MPH1; Christian C. Abnet, PhD, MPH1; et alBarry I. Graubard, PhD2; Linda M. Liao, PhD1; Laura E. Beane Freeman, PhD3; Jonathan N. Hofmann, PhD3; Neal D. Freedman, PhD, MPH1; Rashmi Sinha, PhD1

JAMA Netw Open. 2024;7(6):e2418729. doi:10.1001/jamanetworkopen.2024.18729
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Key Points
Question What is the association between long-term, daily multivitamin use and mortality in generally healthy adults?

Findings In this cohort study of 390 124 generally healthy adults with more than 20 years of follow-up, daily multivitamin use was not associated with a mortality benefit.

Meaning These findings suggest that multivitamin use to improve longevity is not supported.

Abstract
Importance One in 3 US adults uses multivitamins (MV), with a primary motivation being disease prevention. In 2022, the US Preventive Services Task Force reviewed data on MV supplementation and mortality from randomized clinical trials and found insufficient evidence for determining benefits or harms owing, in part, to limited follow-up time and external validity.

Objective To estimate the association of MV use with mortality risk, accounting for confounding by healthy lifestyle and reverse causation whereby individuals in poor health initiate MV use.

Design, Setting, and Participants This cohort study used data from 3 prospective cohort studies in the US, each with baseline MV use (assessed from 1993 to 2001), and follow-up MV use (assessed from 1998 to 2004), extended duration of follow-up up to 27 years, and extensive characterization of potential confounders. Participants were adults, without a history of cancer or other chronic diseases, who participated in National Institutes of Health–AARP Diet and Health Study (327 732 participants); Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (42 732 participants); or Agricultural Health Study (19 660 participants). Data were analyzed from June 2022 to April 2024.

Exposure Self-reported MV use.

Main Outcomes and Measures The main outcome was mortality. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% CIs.

Results Among 390 124 participants (median [IQR] age, 61.5 [56.7-66.0] years; 216 202 [55.4%] male), 164 762 deaths occurred during follow-up; 159 692 participants (40.9%) were never smokers, and 157 319 participants (40.3%) were college educated. Among daily MV users, 49.3% and 42.0% were female and college educated, compared with 39.3% and 37.9% among nonusers, respectively. In contrast, 11.0% of daily users, compared with 13.0% of nonusers, were current smokers. MV use was not associated with lower all-cause mortality risk in the first (multivariable-adjusted HR, 1.04; 95% CI, 1.02-1.07) or second (multivariable-adjusted HR, 1.04; 95% CI, 0.99-1.08) halves of follow-up. HRs were similar for major causes of death and time-varying analyses.

Conclusions and Relevance In this cohort study of US adults, MV use was not associated with a mortality benefit. Still, many US adults report using MV to maintain or improve health.

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