Taking oral contraceptives may reduce the risk for rheumatoid arthritis, a new study has found. The exact cause of rheumatoid arthritis is unclear, but since it is about three times more common in women than in men, some have suggested that hormonal factors might be involved. Swedish researchers studied 2,641 women with the disease and 4,251 healthy controls. They did blood tests and collected health and behavioral data, including information about their reproductive history, breast-feeding and use of contraception. The study followed them for eight years. Women in the study had used oral contraceptives for an average of seven years. After adjusting for age, alcohol consumption, smoking and other factors, current users were 15 percent less likely, and past users 13 percent less likely, than those who had never used oral contraceptives to develop rheumatoid arthritis. Users with positive blood tests for the antibody called ACPA, a predictor of rheumatoid arthritis, reduced their risk by 16 percent.

$1 hike in cigarette prices boosts quitting

When the price of a pack of cigarettes increases by $1, there is a 20 percent increase in rates of quitting smoking. Researchers linked data on the smoking habits of 632 smokers, average age 58, to neighborhood cigarette prices in 896 chain grocery and drugstores in 19 states. They gathered data on local laws on indoor smoking in public places, and followed changes in prices, laws and smoking habits over 10 years. The study, in Epidemiology, found that a $1 increase in price was linked to a 7 percent reduction in the risk of heavy smoking (10 cigarettes or more a day), and a 35 percent reduction in the average number of cigarettes smoked by heavy smokers. At the same time, they found no effect of price on smoking relapse, and local smoking bans had little impact on any of their estimates.

Familial traits behind metabolic problems

Studies have shown that obese women give birth to larger babies who are at risk for obesity and other metabolic problems later in life. Some have thought that the reason may be that obese mothers, whose bodies are rich in nutrients, somehow “overfeed” the fetus during gestation. A new study has found that this is unlikely. The study, in PLOS Medicine, looked at more than 10,000 mother-child pairs, following their offspring into early adulthood. Researchers had data on body mass index, education, occupation and smoking behavior for both mothers and fathers. They also did tests for 153 metabolic traits in the children, including levels of fats in the blood. They found that both maternal and paternal BMI were associated strongly with the metabolic traits of their children. Since paternal BMI cannot affect the fetus during its development, this suggests that familial traits, rather than “programming” in the womb, are the explanation for metabolic abnormalities in the children of obese mothers.