r/HotScienceNews

In 2004, researchers in New York invited hundreds of mothers and their 3-year-olds into a lab to read books and build with blocks while a camera rolled. Coders scored every session for warmth, encouragement and support, and for harshness and intrusiveness. Then the team kept coming back. Over the next 15 years they recorded the brain activity of 465 of those children at ages 9, 12, 15 and 18, focusing on one signal that earlier research has tied to depression. The question was whether a few lab games at age 3 could say anything about how positive parenting shows up in a teenager’s brain.

Married people tend to live longer, and for decades studies have hinted that men get more out of marriage than women do. Researchers at Chapman University and UCLA went looking for that gap in DNA itself. They took blood samples from 762 American adults, most of them in midlife, and ran them through three epigenetic clocks, tools that estimate how fast the body is aging from chemical marks on the genome. One group stood out.

A 2016 study by researchers at Yale University published in Social Science & Medicine investigated the relationship between reading and longevity. The study used data from the Health and Retirement Study , a representative sample of Americans who were surveyed repeatedly between 1998 and 2010. Of the 3,635 Americans surveyed, 50 years old and above, those who engaged in regular reading activities had lower mortality risks than those who did not.

The researchers controlled for age, gender, race, education, wealth, marital status, employment status, self-reported health status, eyesight, depression, and chronic disease. When controlling for all these factors, compared to non-readers, book readers had a 20% lower risk of mortality. Additionally, there was a dose-response association, whereby the higher the number of hours read per week, the lower the risk of dying. Specifically, individuals who read for up to 3.5 hours per week had a 17% lower risk of mortality, while those who read more than 3.5 hours per week had a 23% lower risk.

Compared to newspaper and magazine readers, book readers had the highest risk reduction for all levels of reading frequency. The cognitive stimulation theory may explain the observed correlation between book reading and survival. Controlling for covariates, book reading had a significant association with survival. In the unadjusted model, book readers had an 80% survival chance, 23 months longer than the non-reader group. On average, the survival time for readers was 23 months, and the hazard ratio for all-cause mortality was 0.80 among book readers compared to non-readers.

The study establishes a correlation between book reading and increased survival but does not indicate a causal relationship. Further, the analysis was based on a single measure of the exposure variable. Because the study was observational and relied on self-reported data, residual confounding factors could account for the observed association. Finally, although the results were consistent across various models, the study’s findings only apply to older Americans.

In 2004 and 2005, more than 300,000 South Koreans aged 40 and over went in for a routine national health check. Like most check-ups anywhere, it included a standard blood count, the kind of test that usually gets a quick glance and a "your numbers look fine." Researchers at Dong-A University in Busan then followed those people through national insurance records for up to 15 years to see who developed dementia. One familiar number on that old lab sheet turned out to matter.

Most people don’t choose their hospital. The ambulance goes to the nearest one, or the insurance plan decides. Few patients know whether that hospital is run as a nonprofit or by a company that answers to shareholders. Researchers at the University of Pennsylvania compared 143 for-profit and 798 nonprofit hospitals across 10 US states, using records from more than 1.17 million Medicare patients and surveys of 17,368 bedside nurses, to see whether ownership tracks with who survives a hospital stay. They also tested one specific explanation: how many patients each nurse is asked to care for.

Most people know their weight. Far fewer know their waist-to-height ratio, a simple number that captures how much fat sits around the middle. Researchers in Norway followed 8,797 people across 35 years, measuring their waists and weight again and again, then tested their blood in old age for p-tau217, a protein fragment that tracks the brain changes of Alzheimer’s disease. People who carried the most belly fat in midlife had higher levels of that protein decades later. What the researchers found when they looked at the same measurements taken after 70 was harder to explain.

Doctors have shown the immune system can be primed to keep the virus in check — a promising advance just as US funding cuts threaten future research.