A causal link between increased BMI and risk for ischemic heart disease has been found, according to researchers in Denmark, who said their findings have important public health implications.
“In two large studies of the general population, observational estimates suggested a 26% increase in risk of ischemic heart disease (IHD) for every 4 kg/m² increase in BMI,” the researchers wrote.
Børge Nordestgaard, MD, DMSc, a researcher in the department of clinical biochemistry at Copenhagen University Hospital, Denmark, and colleagues conducted a Mendelian randomization analysis using data from three studies: Copenhagen General Population Study (CGPS, 2003-ongoing), Copenhagen City Heart Study (CCHS, 1976-1978, with follow-up: 1981-1983, 1991-1994, and 2001-2003) and the Copenhagen Ischemic Heart Disease Study (CIHDS, 1991-2009).
Two population-based and one case-control study measured the BMI of 75,627 patients, identified 11,056 IHD events and genotyped FTO (rs9939609), MC4R (rs17782313) and TMEM18 (rs654238).
Observational analyses for IHD revealed an OR of 1.26 (95% CI, 1.19-1.34) for every 4 kg/m² increase in BMI. A 1-unit allele score increase was also associated with a 0.28 kg/m² (95% CI, 0.2-0.36) increase in BMI and an OR for IHD of 1.03 (95% CI, 1.01-1.05). This yielded an average 1.68 kg/m² BMI increase and an 18% increase in the odds of IHD for patients carrying all six BMI-increasing alleles, the researchers wrote.
“In the context of recent, high impact, observational findings, this work has important policy implications for public health given the continuous nature of the BMI-IHD association, the modifiable nature of BMI, and the likely benefits of reducing BMI even by moderate levels,” they concluded.
Disclosure: One of the study researchers is on the editorial board of PLoS Medicine. The other researchers report no relevant financial disclosures.