Soon after birth, babies whose mothers smoked during pregnancy have exaggerated reactions to stress compared with babies of nonsmoking mothers. Like adult smokers, the babies of smokers have spikes in blood pressure after stress, such as an abrupt change in body position. The Swedish researchers who discovered this response now report that babies of smokers continue to have abnormal blood pressure reactions to stress later in their first year.
Dr. Gary Cohen and his colleagues from the Karolinska Institute tested two groups of babies: 19 whose mothers said they smoked about 15 cigarettes a day, and 17 babies of nonsmokers. While the babies napped, the researchers tilted them upright and measured their blood pressure and heart rate. The tests were done when babies were 1 week old, 3 months old, and 1 year old.
In the babies of smokers, blood pressure rose 10 percent after the repositioning when they were 1 week old but only 4 percent when they were 1 year old. In the babies of nonsmokers, the rates were reversed: a 2 percent increase at 1 week old and a 10 percent increase at 1 year old. When the babies were returned to horizontal, smokers’ babies had a 15 percent surge in blood pressure before returning to previous levels, but nonsmokers’ babies slowly returned to normal.
Being unable to control blood pressure properly might be a precursor of high blood pressure as these babies grow up, the authors said, based on studies in adults.
BOTTOM LINE: Babies whose mothers smoked during pregnancy showed differences in how their bodies regulate blood pressure during the first year of life compared with babies of nonsmokers.
CAUTIONS: The researchers relied on mothers’ reports of their smoking, and the study was small.
WHAT’S NEXT: The researchers will track the children in the study to see if they develop problems as they grow older.
WHERE TO FIND IT: Hypertension, March
Weight training linked to better cognitive functionOlder people who exercise are more likely to keep mentally sharp than their less-active peers, research has shown. But the studies haven’t made a distinction between aerobic exercise, such as walking and swimming, and resistance training, such as lifting weights, using weight machines, or doing squats and lunges. A new Canadian study suggests that older women who do resistance training may see cognitive benefits.
Teresa Liu-Ambrose of the University of British Columbia led a team that randomly assigned 155 women, ages 65 to 75, to three different exercise classes. Some had resistance training once a week, some had resistance training twice a week, and some had tai chi-based balance and tone training twice a week.
After one year, the women in the resistance training groups performed better than the women in the balance and tone group on two cognitive skills important for decision making: selective attention and conflict resolution. The once-weekly group improved their scores by 10.9 percent from the start of the study, and the twice-weekly group went up by 12.6 percent. In contrast, the balance and tone group’s scores fell 0.5 percent.
BOTTOM LINE: Older women who exercised with weights once or twice a week for one year performed better on tests of cognitive ability.
CAUTIONS: The results may not apply to men, or to women of other ages.
WHERE TO FIND IT: Archives of Internal Medicine, Jan. 25