Vitamin E administration may decrease the incidence of pneumonia in elderly males

Abstract

Background

Vitamin E has influenced the immune system in laboratory studies. Dozens of animal experiments have found that vitamin E offered protection against infections caused by viruses and bacteria. Previously, significant heterogeneity was found in the effect of vitamin E supplementation on pneumonia in humans. The aim of this study was to examine how the effect of vitamin E on pneumonia risk depends on age.

Methods

Secondary analysis of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention study in Finland, 1985–1993, was performed. Participants were male smokers aged 50–69 years at the baseline who started to smoke at ≥21 years (N=7,469). Intervention was 50 mg/d of vitamin E for 5–8 years. The outcome was the incidence of hospital-treated, community-acquired pneumonia by the age at the follow-up.

Results

Among 2,216 participants who smoked 5–19 cigarettes per day at baseline and exercised at leisure time, vitamin E supplementation reduced the incidence of pneumonia by 69% (95% confidence interval [CI]: 43%–83%; 57 pneumonia cases). In this subgroup, vitamin E prevented pneumonia in 12.9% of participants by the age of 74 years. Among 5,253 participants who smoked ≥20 cigarettes per day at baseline or did not exercise, the incidence of pneumonia was 14% lower in the vitamin E participants (95% CI: −38% to +21%; 139 cases). One-third of the participants quit smoking for a period, of whom 27 got pneumonia. The incidence of pneumonia was 72% (95% CI: 31%–89%) lower in the vitamin E group, and this benefit was also seen among those males who smoked ≥20 cigarettes per day at baseline or did not exercise.

Conclusion

Although the evidence of benefit from vitamin E against pneumonia in elderly males is strong in this analysis, the overall findings about vitamin E have been complex. Further research on vitamin E in nonsmoking elderly males is warranted.

Keywords:

• antioxidants
• exercise
• randomized controlled trial
• respiratory tract infections
• smoking

Acknowledgments

The author thanks the ATBC study (The National Institute for Health and Welfare, Finland, and the National Cancer Institute, Rockville, MD, USA) for access to the data. The author had full access to all of the data in this study and takes responsibility for the accuracy of the data analysis.

Trial registration: NCT0342992.

Disclosure

No external funding was received for this analysis. The author reports no conflicts of interest in this work.