Lower vitamin K levels linked to poor lung function, greater COPD, asthma risks

Key takeaways:

• Low vitamin K levels appeared linked to decreased measures of FEV₁ and FVC following adjustments for several variables.
• The risk for self-reported COPD, wheezing and asthma was heightened with lower vitamin K.

Lower vitamin K levels appeared associated with declines in lung function measures and greater risk for self-reported COPD, asthma and wheezing, according to study results published in ERJ Open Research.

Torkil Jespersen

“[This study] shows a need for more extensive studies on whether lung patient groups and the general population may benefit from taking vitamin K supplements,” Torkil Jespersen, MD, master’s thesis student in the Center for Clinical Research and Prevention at Frederiksberg Hospital in Denmark, told Healio.

In a cross-sectional population-based study, Jespersen and colleagues analyzed 4,092 adults (age range, 24 to 77 years) from the Danish study of Functional Disorders general population cohort to determine how vitamin K levels are related to lung function and lung diseases using regression models adjusted for age, sex and height.

Researchers collected spirometry and dephosphorylated-uncarboxylated Matrix Gla protein (dp-ucMGP) plasma levels — higher levels of which suggested lower vitamin K levels — and had the participants complete questionnaires.

Reduced measures of FEV₁ and FVC appeared related to low vitamin K levels/increased dp-ucMGP (FEV₁ per doubling of dp-ucMGP = –97.8 mL; 95% CI, –141.3 mL to –54.4 mL; FVC per doubling of dp-ucMGP = –136 mL; 95% CI, –187.2 mL to –84.9 mL) in the model adjusted for age, sex and height.

Researchers continued to observe declines in these measures with the doubling of dp-ucMGP following further adjustment for weight and kidney function (FEV₁ = –72.8 mL; 95% CI, –117.5 mL to –28.2 mL; FVC = –84.2 mL; 95% CI, –136.3 mL to –32.2 mL) and for smoking, alcohol consumption, physical activity, fitness and healthy eating (FEV₁ = –50.3 mL; 95% CI, –95 mL to –5.5 mL; FVC = –54.8 mL; 95% CI, –107.4 mL to –2.1 mL).

Additionally, doubling of dp-ucMGP increased the risk for FEV₁ and FVC below lower limit of normal (FEV₁, adjusted OR = 2.41; 95% CI, 1.65-3.52; FVC, aOR = 2.48; 95% CI, 1.46-4.22) in the model adjusted for age, sex and height, although researchers noted this association lessened with further adjustments.

Researchers did not find a link between vitamin K and FEV₁/FVC ratio.

“We were surprised to find vitamin K status was not associated with lower FEV₁/FVC ratio, which one would expect to see in obstructive lung diseases such as asthma and COPD,” Jespersen told Healio.

Lastly, researchers observed heightened odds for self-reported lung diseases/symptoms in the fully adjusted model when individuals had low vitamin K levels/doubled dp-ucMGP plasma, with the greatest risk found for COPD (aOR = 2.09; 95% CI, 1.35-3.23), followed by wheezing (aOR = 1.4; 95% CI, 1.08-1.81) and asthma (aOR = 1.29; 95% CI, 0.99-1.67).

“Future studies will be prospective, meaning they will follow vitamin K status and lung function in individuals over time,” Jespersen told Healio. “Further, several authors of the article are currently involved in a long-term randomized placebo-controlled trial (InterVitaminK) to see whether vitamin K supplementation influences age-related diseases including chronic lung disease.”

Reference:

• Large study suggests people with low levels of vitamin K have less healthy lungs. https://www.eurekalert.org/news-releases/997950. Published Aug. 9, 2023. Accessed Aug. 9, 2023.

For more information:

Torkil Jespersen, MD, can be reached at torkil.jespersen.02@regionh.dk.