Christopher Martyn: Research round-up

chris_martynAnnals of Internal Medicine

Mistreatment of residents in nursing homes

Conditioned by reports in the media about mistreatment of residents in nursing homes, one leaps to the conclusion that it must be the staff who are doing the mistreating. This study suggests that it’s more likely that the other residents are to blame. Two thousand elderly people living in nursing homes in New York state were observed and interviewed over a month. More than 20% reported experiencing at least one episode of abuse from their peers. Verbal aggression was the most common form, but invasion of privacy, menacing gestures, and physical attacks also occurred frequently.



Unlike continuous high levels of parathyroid hormone, which cause bone resorption, intermittently high levels stimulate osteoblasts and have an anabolic effect on bone. This is the rationale for using teriparatide, a recombinant parathyroid hormone analogue, in the secondary prevention of osteoporotic fracture. This randomised controlled trial shows that another parathyroid hormone analogue, abeloparatide, with slightly different binding characteristics, is also anabolic for bone. However, the primary endpoint was radiological evidence of new vertebral fracture, and the comparison was with placebo. So the important question of whether abeloparatide is more effective or safer than teriparatide remains unanswered.


Exacerbations of asthma no more likely with paracetamol than ibuprofen

Anxiety that paracetamol might make asthma worse has been nagging away for a while, but this randomised controlled trial goes a long way to show that it’s probably misplaced. Three hundred children with mild persistent asthma were recruited and randomised either to receive paracetamol or ibuprofen if they needed symptomatic treatment for pain or fever over the next 48 weeks. The incidence of exacerbations of asthma severe enough to require systemic glucocorticoids turned out to be no higher in children allocated to paracetamol than in those allocated to ibuprofen.

Obeticholic acid for primary biliary cholangitis

Primary biliary cholangitis is the new name for primary biliary cirrhosis, a rare autoimmune liver disease which for unknown reasons is 10 times more prevalent in women than men. Current treatment relies on ursodiol, which improves biochemical indicators of liver function and delays the time to liver transplantation. Phase 2 studies suggested additional benefit from the selective farnesoid X receptor agonist, obeticholic acid, although at the cost of worsening pruritis. This year long phase 3 trial in 217 patients with primary biliary cholangitis confirms that obeticholic acid persistently lowers alkaline phosphatase and total bilirubin concentrations, but it was too small to show whether clinical outcomes were also improved.


Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents

A meta-analysis of individual level data from more than 10 million adults living in 32 countries in Asia, Australasia, Europe, and North America finds that mortality is lowest among people with BMIs in the range 20 – 25. Mortality increased significantly above and below this range – a finding which calls into question results from earlier studies that suggested being overweight or even moderately obese carried no excess risk. Associations between BMI and mortality were broadly similar in all geographical regions, but the strength of the relation diminished in people over 70 years of age. As an accompanying editorial points out, turning this information into useful public health recommendations won’t be straightforward. Non-surgical interventions to promote weight loss are only modestly effective.

Human neural stem cells after stroke

The ability to replace damaged or defective brain tissue by implantation of stem cells would be a huge advance. Perhaps this report of a stereotaxic procedure, in which engineered human neural stem cells were injected into the putamens of 11 chronic stroke patients, will prove a step in the right direction. No long term adverse effects were attributed to the procedure and some of the patients seemed to benefit. However, as the investigators admit, the lack of a control group means that this sort of evidence has to be treated with extreme caution. What’s more, any neurological change might be the result of the stereotactic procedure rather than the implantation of stem cells. And there’s always the possibility of a Hawthorn effect.

Preventing dementia

To explore community based strategies for reducing dementia, this trial recruited 3526 people aged 70–78 years from general practices in the Netherlands. Participants were randomly assigned either to a repeated nurse-led intervention designed to minimize levels of cardiovascular risk factors or to usual care. Over nearly 7 years of follow up, dementia developed in 7% of people in the intervention group and in 7% of the control group. The incidence of cardiovascular disease didn’t differ between the two groups either. The investigators wonder if these disappointing results are explained by modest baseline cardiovascular risks and high standards of usual care.

Risk factors for stroke around the world

The second phase of the INTERSTROKE study, a case-control study in 32 countries in Asia, America, Europe, Australia, the Middle East, and Africa, recruited more than 13 000 people with stroke and matched them for age and gender with a similar number of controls. The headline finding is that 10 potential modifiable risk factors (hypertension, smoking, diabetes mellitus, physical activity, diet, psychosocial factors, abdominal obesity, alcohol consumption, cardiac causes, and apolipoprotein levels) account for 90% of the population attributable risk of all types of stroke in all regions of the world. But of course there are large regional variations in the relative importance of these individual risk factors.

Christopher Martyn was previously an epidemiologist and editor of the QJM. He now works freelance.