People who are carriers of life shortening genes can reduce their risk of dying early by more than 60 percent if they follow a healthy lifestyle, suggest results from a large observational study led by Zhejiang University School of Medicine in China.
As reported in the BMJ Evidence-Based Medicine, the authors used data from 353,742 participants of European ancestry with a median follow-up of 12.86 years who came from various large cohort studies or biobanks: LifeGen, U.S. National Health and Nutrition Examination Survey, and the UK Biobank. Overall, 24,239 people across the cohorts died during the follow-up period.
The researchers found an unhealthy lifestyle, including factors such as current smoking, excess alcohol consumption, not enough physical activity, unhealthy body shape and overweight, poor sleep duration, and an unhealthy diet can increase a person’s risk for dying by 78% compared to a healthy lifestyle.
To add to this, the research team created a polygenic risk score to assess whether a person was likely to have a short, medium or long lifespan.
The researchers multiplied the number of alleles linked to shorter lifespan by a single nucleotide polymorphism’s (SNPs) effect on lifespan and added all the results together to form a score. Overall, those in the short genetic lifespan group (20 percent of group) had a 21 percent increased risk for dying during follow-up compared with those in the long genetic lifespan group (20 percent of group).
When genetic risk and lifestyle factors were added together, having a short genetic lifespan prediction and living an unhealthy lifestyle increased risk of dying by 2.04-fold during follow up compared with having a long lifespan prediction and living a healthy life.
“In our study, we found that a healthy lifestyle could lower overall risk within and between genetic risk groups, and the genetic predisposition to a shorter lifespan can be substantially compensated by having a healthy lifestyle,” write the investigators.
“Participants with high genetic risk could prolong approximately 5.22 years of life expectancy at age 40 with a favorable lifestyle. Given that lifestyle behavioral habits are usually developed before middle age, taking effective public health interventions is quite crucial for those at high genetic risk to extend their lifespan before the formation of a fixed lifestyle.”
