Pulmonary function and uric acid . . . and other storiesBMJ 2018; 360 doi: https://doi.org/10.1136/bmj.k28 (Published 11 January 2018) Cite this as: BMJ 2018;360:k28
Uric acid and the lungs
Uric acid has antioxidant properties, and Danish investigators wondered if it might protect against impaired pulmonary function. In fact, the reverse seemed to be true since, in two longitudinal studies in Copenhagen, people with high plasma urate levels tended to have poorer lung function and more respiratory symptoms. However, genotyping of participants showed that genetic variants known to be linked to high plasma urate levels were not associated with respiratory outcomes, which suggests that there is no causal relation operating in either direction (Thorax doi:10.1136/thoraxjnl-2017-21027).
The President’s Malaria Initiative
It’s too soon to know how history will judge President G W Bush. However, the way in which he channelled US foreign aid into measures to control malaria will surely weigh in his favour. A modelling study in PLoS Medicine reckons that since 2005, when the President’s Malaria Initiative began, the combination of nets treated with insecticide, indoor spraying, and artemisinin combination therapy has prevented around 200 million cases and saved a million lives (PLOS Med doi:10.1371/journal.pmed.1002448). The investigators judge the interventions to be highly cost effective and argue that funding should be continued.
Marriage and dementia
A systematic review finds that married people have a slightly lower risk of dementia than either people who are single throughout their lives or people who are widowed (J Neurol Neurosurg Psychiatry doi:10.1136/jnnp-2017-316274). Divorce, on the other hand, makes no difference. It’s well known that married people have a healthier way of life than single people and, since the differences between the groups were reduced after adjusting for poor health, this might be the explanation rather than marriage having any direct cognitive benefit.
Green leafy vegetables
On the subject of cognitive decline, a longitudinal study of nearly 1000 elderly people in the US suggests that a diet rich in green leafy vegetables has a useful preventive effect (Neurology doi:10.1212/WNL.0000000000004815). The rate of decline among those who consumed 1–2 servings per day was the equivalent of being 11 years younger when compared with those who rarely or never consumed green leafy vegetables. Folate, phylloquinone, and lutein seemed to be the most active nutrients.
Appendicitis in children
Compared with appendicectomy, conservative treatment of appendicitis is less efficacious and more likely to require readmission, according to a systematic review of five studies of children with acute uncomplicated appendicitis (Arch Dis Child doi:10.1136/archdischild-2017-313127). Unfortunately, only one of the five studies was randomised. The others allowed patients, parents, or doctors to choose between treatments. What’s more, the studies used different antibiotic regimens, so this is unlikely to be the final word on the subject.
Maternal diet and asthma in children
The idea that exposure to ω-3 long-chain fatty acids in the womb protects against atopic conditions in childhood gets no support from an analysis of pooled data from more than 60 000 mother-child pairs from 18 birth cohorts (Int J Epidemiol doi:10.1093/ije/dyx007). Fish consumption by mothers during pregnancy varied from less than once every two weeks in the Netherlands, to more than four times a week in Spain. But there was no association between maternal fish intake and symptoms of wheeze in their offspring at any age, nor with risk of asthma or allergic rhinitis at school age.