“Research highlights” is a weekly round-up of research papers appearing in the print BMJ. We start off with this week’s research questions, before providing more detail on some individual research papers and accompanying articles.
- Does vitamin D supplementation improve bone mineral density in healthy children?
- What are the perspectives of people living and dying with severe chronic obstructive pulmonary disease, and of their informal and professional carers?
- Does regular use of non-steroidal anti-inflammatory drugs decrease the risk of Parkinson’s disease?
- How accurate is cholesterol monitoring for detecting non-adherence with cholesterol lowering treatment?
Palliative care for COPD
Chronic obstructive pulmonary disease (COPD) can be a serious terminal illness, but, according to qualitative research by Hilary Pinnock and colleagues, few patients, carers, or even healthcare professionals view the disease this way.
The 21 patients and 13 carers they interviewed described COPD as a “way of life,” with only severe exacerbations classified as real illness. “Patients passively accept their lot and see the increasing disability as part of normal ageing,” say editorialists Andrew Thorns and Declan Cawley of the study’s findings.
The patients’ “disease stories” were impossible to distinguish from their life stories, with no clear beginning and an unpredictable end, unlike patients with cancer, who often give a clear account of their diagnosis and how their life has been disrupted since.
This lack of a clear narrative and the fact that patients seem to passively accept the limitations imposed by COPD mean that it’s hard to distinguish a point at which starting palliative care would be appropriate, say the authors. They suggest that clinicians should proactively assess the needs of patients with COPD at milestones such as starting long term oxygen therapy and admission to hospital for an exacerbation.
How to deal with exacerbations is discussed in some depth in a clinical review from Drug and Therapeutics Bulletin. The evidence behind the various pharmacological and non-pharmacological approaches available is reviewed, although unsurprisingly the most effective intervention is stopping smoking.
Vitamin D supplements for children’s bones
Osteoporosis is a common and costly public health problem, and maximising bone mass early in life may be an important way to tackle it. Improving children’s levels of vitamin D is one strategy that’s been tested, but the results of randomised controlled trials of supplementation in young people have been inconsistent. Tania Winzenberg and colleagues did a meta-analysis to find out whether the evidence supported the use of vitamin D supplements to increase peak bone mass in children and adolescents. Their assessment of data from six studies, including almost 800 participants, showed no difference between vitamin D supplementation and placebo for effects on total body bone mineral content or on bone mineral density of the hip or forearm. A planned subgroup analysis suggested that supplementation could bring about clinically useful improvements, particularly in lumbar spine bone mineral density and total body bone mineral content, in children and adolescents who initially had a vitamin D deficiency, but the authors say that this finding requires confirmation.
Do NSAIDs protect against Parkinson’s?
The idea that non-steroidal anti-inflammatory drugs (NSAIDs) might confer protection against Parkinson’s disease has been around for a while, partly backed up by some epidemiological studies. But Jane Driver and colleagues found no evidence for the association.
This case-control study, nested within the prospective Physician’s Health Study, included 22, 007 US male physicians aged 40-84 followed up for 25 years. In all 616 cases of incident Parkinson’s disease were matched to 3080 controls by age, and for this comparison the drugs seemed to be protective. But, when the authors looked at 565 cases and 2458 controls matched by age and by scores for confounders (comorbidity and indicators of NSAID use), the apparent protective effect disappeared. Timing played a part too. Pain often precedes the main symptoms and signs of Parkinson’s disease and, sure enough, use of NSAIDs by the cases in this study was clustered in the few years before their diagnosis of Parkinson’s disease: without further adjustment this could have looked like a possibly causative link.
We particularly liked the way this study illustrates the perils of “confounding by indication.” Anyone running a journal club would do well to read the paper’s full discussion section on bmj.com.
Research online: For these and other new research articles see www.bmj.com/research
Do women’s magazines influence caesarean rates?
Articles on caesarean section in Brazilian women’s magazines provide an incomplete picture of the benefits and risks associated with the procedure and do not use optimal sources of information, according to research by Maria Regina Torloni and colleagues. Their analysis of 118 articles published between 1988 and 2008 in the top selling women’s magazines in Brazil, a country with one of the highest caesarean section rates in the world, found that almost all (94%) were written exclusively by journalists, although almost 80% cited health professionals as the main source of information. A total of 71% reported at least one benefit of caesarean section and 82% reported at least one short term maternal risk, but only a third mentioned any long term maternal risks or perinatal complications.