Understanding the biological pathways underlying atrial fibrillation

A team led by Patrick Ellinor, MD, PhD, of the MGH Heart Center, conducted a genomic analysis for atrial fibrillation (AF) – an irregular and often rapid heart rate that can increase the risk for stroke. Using data from more than 50 studies worldwide, they identified nearly 100 genetic regions associated with AF, including 70 which were not previously linked to irregular heartbeat. The detected genetic regions implicate genes involved in the heart’s development and function. These results, published in Nature Genetics, could help in developing new treatments for AF.

Impact of quantity and quality of sleep on cardiovascular risk factors in adolescents

Earlier research has linked shorter sleep duration with increased obesity levels in children, but few studies have examined the effects of too little sleep on other cardiovascular risk factors – such as blood pressure – or examined associations of sleep quality with these outcomes.

A study in the journal Pediatrics led by Elsie Taveras, MD, MPH, of MassGeneral Hospital for Children, found that both the amount of time spent sleeping and the percentage of sleep that is undisturbed have significant effects on aspects of cardiovascular health such as blood pressure, cholesterol levels and abdominal fat deposition in young adolescents.

The findings suggest a lack of good sleep could be setting children up for serious health issues later in life and emphasize the importance of establishing healthy sleep patterns.

Identifying the genetic roots and gene transfer of cholera

Recent data show that new cholera epidemics like those in Haiti, Africa and Yemen are imported from cholera’s ancestral home in South Asia. This underscores the importance of understanding cholera in South Asia to control cholera globally.

In this study, published in Nature Genetics, a team led by Edward Ryan, MD, of the Infectious Diseases Division, analyzed the organism that causes cholera in its ancestral home in Bangladesh. They found that multiple strains of cholera can circulate simultaneously, even within a single individual, which can lead to genetic transfers and formation of new strains.

They also found that all strains currently circulating in Bangladesh descend from a common ancestor dating back to massive regional floods in the 1980s, suggesting that a given strain can explode when optimal conditions come into existence, giving rise to new and evolving sub-strains in South Asia and facilitating outbreaks of new epidemics into other at-risk communities around the world.

Effects of police killings on mental health of black Americans

Recent research led by Alexander Tsai, MD, PhD, of the Department of Psychiatry, published in The Lancet found that police killings of unarmed black Americans produce significant collateral mental health fallout among black Americans in the general population who are not directly affected by the killings. Neither police killings of armed black or white individuals had any significant effects on the mental health of black Americans, and similar effects were not seen among white Americans. Those results suggest it is the social meaning of these killings, not just the indirect exposure to violence, that could explain the findings.

At the population level, these killings resulted in more than 50 million additional days of poor mental health per year among black Americans, comparable to the mental health burden attributable to diabetes in the entire population.

Read more articles from the 07/13/18 Hotline issue.