Childhood obesity ups risk of essential hypertension

Birth weight does not increase the risk of essential hypertension, but childhood obesity appears predictive of such risk, a study has found.

This finding may help explain the mechanisms of essential hypertension and contribute to the development of strategies for its prevention, according to the investigators.

This study sought to explain the causal relationship between birth weight, childhood obesity, and essential hypertension by Mendelian randomization (MR) with genetic variants as instrumental variables (IVs). The investigators identified IVs based on single nucleotide polymorphisms (SNPs) associated with birth weight (n=160,295) and childhood obesity (n=6,889: 1,509 cases and 5,380 controls) from the meta-analysis of a genome-wide association study.

The association between IVs and essential hypertension was analysed using summary level data from the UK Biobank essential hypertension consortium (n=463,010: 54,358 cases and 408,652 controls). To ensure robustness of the results, the investigators used two MR analysis methods, two threshold values of selecting IVs, and leave-one-out analysis.

Genetic predisposition to higher birth weight was not associated with an increased risk of essential hypertension. On the other hand, each standard deviation increase in childhood body mass index showed a causal relationship with a higher risk of essential hypertension (odds ratio, 1.0075, 95 percent confidence interval, 1.0035–1.0116) when using seven SNPs that achieved genome-wide significance (p<5x10^-8).

Results were robust and not influenced by pleiotropy in sensitivity analysis and MR-Egger regression.