Research highlights – 3 December 2010

Research questions“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.

Tackling chronic obstructive pulmonary disease in Guangdong, China
Around 8% of Chinese people aged 40 have chronic obstructive pulmonary disease (COPD). While this proportion is lower than the worldwide prevalence of 10%, it probably reflects the fact that, even though a third of the world’s smokers live in China, tobacco use has been widespread there for fewer years than in the West.

Yumin Zhou and colleagues report on a remarkable cluster randomised controlled trial to both prevent and treat COPD in middle aged and older people in Guangzhou city, Guangdong, where an extensive and complex intervention was offered in one of two communities ( The main components were a public health education campaign, the cleaning up and eventual relocation of a local cement factory, and – for people with COPD – personal care plans, bronchodilators, personalised advice on smoking cessation, and nicotine replacement therapy through tea and patches.

In the intervention community there was a significant improvement in the primary outcome measure, the annual rate of decline in forced expiratory volume in one second (FEV1). Secondary outcomes during the four year follow-up were significantly improved too: and while some were soft and self reported (smoking cessation and exposure to environmental tobacco smoke) hard outcomes included lower cumulative death rates from all causes, and better outdoor air quality as measured by the local environmental monitoring station. However, there were no differences in cumulative incidence rate of COPD and cumulative death rate from COPD between the two communities.

This trial is included in the Chinese Clinical Trials Registry ( which makes fascinating reading. It currently records more than 1000 studies in English and Chinese and is part of WHO’s registry network.

Psychosis and substance abuse
People in the UK who have psychosis are 25% more likely to have a drink or drug misuse problem than members of the general population. Evidence suggests that the best non-pharmacological approach to treating such individuals is to target their mental health and their substance misuse problem simultaneously, but no integrated psychosocial intervention has been proved to be effective so far.

Christine Barrowclough and colleagues conducted a randomised controlled trial of one such intervention – integrated motivational interviewing and cognitive behavioural therapy – in people with schizophrenia, schizophreniform disorder, or schizoaffective disorder who were diagnosed with dependence on or misuse of drugs, alcohol, or both. They found that adding 12 months of the intervention to standard care had no effect on hospital admissions, death, symptom outcomes, or functioning during the intervention period or in the 12 months after completion of therapy. The intervention did transiently increase patients’ motivation to change, however, and reduced the amount of substance used. Interestingly, the integrated therapy seemed to have more effect on people who misused alcohol than on those who misused drugs, but this finding was from an exploratory subgroup analysis and should therefore be viewed with caution.

The BMJ’s clinical editors were impressed with the authors’ attempts to assess a difficult to study population and believe that the essentially negative findings of this paper are of some importance. “It was a very difficult trial to undertake and I have a considerable sympathy for the researchers,” said Domhnall MacAuley, primary care editor. “As an intervention that, empirically, we might have expected to work, this is a useful negative trial.”

Variation in quality of NHS care
The publication this week of the NHS Atlas of Variation has revealed just how much the quality of NHS healthcare differs around the United Kingdom. The atlas shows that the level and quality of care for conditions such as cancer and stroke can vary by twofold and fourfold, respectively, in different parts of the country.
Dulcie McBride and colleagues’ research provides further evidence of the “postcode lottery” faced by patients in the UK by showing that referrals from primary care vary on the basis of the patient’s age, sex, and level of social deprivation. Patients aged 85 or older were less likely to be referred by their general practitioner for postmenopausal bleeding, hip pain, or dyspepsia than were patients aged 55-64. Furthermore, women with hip pain and people in the lowest fifth in terms of socioeconomic deprivation who had hip pain or dyspepsia were less likely to be referred than men or better off individuals, respectively.

Research online: For these and other new research articles see

Vitamin B, omega 3, and CVD
Observational studies have reported inverse associations between cardiovascular disease and intake of B vitamins and omega 3 fatty acids, but randomised trials have so far failed to establish a link. That remains the case – in France, Pilar Galan and colleagues did a randomised placebo controlled trial in patients with established coronary or cerebrovascular disease, and they found no evidence that daily dietary supplementation with these nutrients reduced the risk of major cardiovascular events.