Dataset Information

Association of milk intake with hay fever, asthma, and lung function: a Mendelian randomization analysis.

ABSTRACT:

Background

Previous observational studies have indicated a protective effect of drinking milk on asthma and allergy. In Mendelian Randomization, one or more genetic variants are used as unbiased markers of exposure to examine causal effects. We examined the causal effect of milk intake on hay fever, asthma, forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) by using the lactase rs4988235 genotype associated with milk intake.

Methods

We performed a Mendelian Randomization study including 363,961 participants from the UK Biobank.

Results

Observational analyses showed that self-reported milk-drinkers vs. non-milk drinkers had an increased risk of hay fever: odds ratio (OR) = 1.36 (95% CI 1.32, 1.40, p < 0.001), asthma: OR = 1.33 (95% CI 1.38, 1.29, p < 0.001), yet a higher FEV1: β = 0.022 (SE = 0.004, p < 0.001) and FVC: β = 0.026 (SE = 0.005, p < 0.001). In contrast, genetically determined milk-drinking vs. not drinking milk was associated with a lower risk of hay fever: OR = 0.791 (95% CI 0.636, 0.982, p = 0.033), and asthma: OR = 0.587 (95% CI 0.442, 0.779, p = 0.001), and lower FEV1: β = - 0.154 (standard error, SE = 0.034, p < 0.001) liter, and FVC: β = - 0.223 (SE = 0.034, p < 0.001) liter in univariable MR analyses. These results were supported by multivariable Mendelian randomization analyses although not statistically significant.

Conclusions

As opposed to observational results, genetic association findings indicate that drinking milk has a protective effect on hay fever and asthma but may also have a negative effect on lung function. The results should be confirmed in other studies before any recommendations can be made.

SUBMITTER: Skaaby T

PROVIDER: S-EPMC7614013 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Publications

Association of milk intake with hay fever, asthma, and lung function: a Mendelian randomization analysis.

Skaaby Tea T Kilpeläinen Tuomas O TO Mahendran Yuvaraj Y Huang Lam Opal LO Sallis Hannah H Thuesen Betina H BH Kårhus Line Lund LL Leth-Møller Katja Biering KB Grarup Niels N Hansen Torben T Pedersen Oluf O Burgess Stephen S Munafò Marcus R MR Linneberg Allan A

European journal of epidemiology 20220103 7

<h4>Background</h4>Previous observational studies have indicated a protective effect of drinking milk on asthma and allergy. In Mendelian Randomization, one or more genetic variants are used as unbiased markers of exposure to examine causal effects. We examined the causal effect of milk intake on hay fever, asthma, forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) by using the lactase rs4988235 genotype associated with milk intake.<h4>Methods</h4>We performed a Mendel ...[more]

PMID: 34978666

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Dataset Information

Association of milk intake with hay fever, asthma, and lung function: a Mendelian randomization analysis.

Background

Methods

Results

Conclusions

Publications

Association of milk intake with hay fever, asthma, and lung function: a Mendelian randomization analysis.

Similar Datasets

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