Genetic Study Strengthens Causal Role of BMI in Heart Disease

Last Updated on

July 07, 2017 – A new study analyzing genetic mutations predisposing to increased body-mass index (BMI) provides strong evidence that higher BMI plays a causal role in type 2 diabetes, hypertension, and coronary heart disease (CHD). The study results strongly suggest that BMI is causally related to increased risk of developing diabetes, hypertension, and CHD if you are born with certain variants of genes that tend to increase your BMI.

The current study used an approach known as a Mendelian randomization (see here for explanation), often referred to as nature’s own randomized study, which focuses on certain gene mutations known to be associated with a given variable, in this case, BMI, and their relationship to certain outcomes, in this case, diabetes, hypertension, and CHD.

For the study, researchers analyzed genetic, medical, and sociodemographic information from 120,000 individuals included in the UK Biobank. A polygenic risk score comprising 93 single-nucleotide polymorphisms (SNP’s)  associated with BMI from previous genomewide association studies was constructed. All participants attended an assessment center where blood pressure was measured and prevalence of hypertension, CHD, and type 2 diabetes were determined based on self-report. Participants also self-reported sociodemographic information pertaining to relevant confounders.

Using the genetic data, results showed that each 4.8-unit increase in BMI was associated with a 35% increased risk of CHD (odds ratio [OR] 1.35; 95% CI 1.09–1.69); a 64% increased risk of hypertension (OR 1.64; 95% CI 1.48–1.83); and a 153% increased risk of type 2 diabetes (OR 2.53; 95% CI 2.0–43.13). However, no associations with pulse rate or stroke were identified. Associations were independent of deprivation scores, alcohol intake, smoking status, age, sex, and antihypertensive medication.

In an accompanying editor’s note, JAMA’s associate editor Dr Christopher J O’Donnell pointed out that in well-established cohorts, BMI has clearly been associated with both traditional risk factors and CHD, but the association of BMI with CHD was found nonsignificant after adjustment for other major modifiable risk factors. The current Mendelian randomization study however refocuses attention on and strengthens the body of evidence / literature for a causal connection of BMI with increasing blood pressure, diabetes, and CHD at least in individuals that carry (the) according genetic disposition(s).

Still further research may be needed to expand the fully understanding the molecular mechanisms that lead  to the observed clinical phenotypes and to further understand which subgroups of individuals are carrying the highest genetically determined risks. For patients, it would be most informative which one(s) of the 93 SNP’s examined carries the highest risk(s) for the clinical endpoints discussed in the present study and how these risk could reasonably be dealt with in real life.

 

 

Tags: , , , , , , ,
About the Author
thassodotcom Ph.D.; Professor in Pharmacology and Toxicology. Senior expert in theragenomic and personalized medicine and individualized drug safety. Senior expert in pharmaco- and toxicogenetics. Senior expert in human safety of drugs, chemicals, environmental pollutants, and dietary ingredients.

Your opinion

Comment

No comments yet

thasso: conditions

thasso: tweets

thasso post: magazine

View my Flipboard Magazine.

thasso: categories

thasso: archives

thasso: simple chat

You must be a registered user to participate in this chat.

  • When macrophages are deprived of oxygen May 24, 2019
    Infected tissue has a low concentration of oxygen. The body's standard immune mechanisms, which rely on oxygen, can then only function to a limited extent. How does the immune system nevertheless manage to control bacteria under such conditions? Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg and University Hospital Regensburg discovered that fewer metabolites are produced in the citric […]
  • Science Snapshots -- May 2019 May 24, 2019
    Researchers at Berkeley Lab's Molecular Foundry have predicted fascinating new properties of lithium; a powerful combination of experiment and theory has revealed atomic-level details about how silver helps transform carbon dioxide gas into a reusable form; new study reports the first comprehensive, highly coordinated effort to examine the global diversity and biogeography of activated sludge […]
  • Information and language in news impact prejudice against minorities May 23, 2019
    Researchers at the Institute of Psychology show how news about immigrants and language describing immigrants shape prejudice against immigrants and other social minorities, as part of the project 'Immigrants in the Media.' For instance, nouns used for describing the ethnicity of immigrants enhance prejudice against immigrants more than adjectives.
  • Artificial atomic scale materials: Discovering how electrons fatten! May 23, 2019
    A single and isolated electron has a clear electrical charge, magnetic moment and mass, and its free movement can be precisely predicted. Spanish scientists fabricated a nanoscale artificial material manipulating atoms one after the other and discovered that electrons around are very heavier. Heavy electrons are promising particles which endow of new functionalities to novel […]
  • Allogeneic stem cell transplantation in non-Hodgkin lymphoma: benefit remains unclear May 23, 2019
    Meaningful studies are lacking for certain patient groups. Disease-specific registries could help close the data gap.
Top