Clinical news roundup

Diabetes-breast cancer link
Diabetologia (2012) DOI 10.1007/s00125-012-2793-9

Patients who survive breast cancer are at increased risk of developing diabetes, emphasising the need for screening and prevention, a study of 24,976 patients and 124,880 controls aged at least 55 years shows.

Breast cancer survivors were significantly more likely to die as a result of diabetes than controls who did not develop the malignancy (by 34 per cent and 36 per cent after one and 12 years follow up respectively). Overall, 9.8 per cent of women with newly diagnosed breast cancer and 9.7 per cent of controls were diagnosed with diabetes during a mean follow-up of 5.8 years.

The risk of developing diabetes increased (by 7 per cent) after two years follow-up and continued to rise over time reaching 21 per cent after ten years. At this point, the cumulative incidence of diabetes was 18.3 and 16.5 per 1,000 person-years among breast cancer survivors and controls respectively.

Among women treated with adjuvant chemotherapy, the risk of diabetes peaked (reaching 24 per cent) in the first two years following diagnosis. After ten years, the cumulative incidence of diabetes was 19.6 and 18.0 per 1,000 person-years in breast cancer patients who received and did not receive adjuvant chemotherapy respectively.

These figures compared to 16.1 and 16.6 per 1,000 person-years in age-matched controls without breast cancer.

Passive smoking pre-disposes children to meningitis
BMC Public Health (2012) 12:1062 doi:10.1186/1471-2458-12-1062

Exposure to second-hand smoke (SHS) increases the risk of invasive meningococcal disease in children, according to a meta-analysis of 18 studies.

Exposure to SHS at home approximately doubled the risk of invasive meningococcal disease (odds ratio [OR] 2.18). The link was especially strong among children less than 5 years of age (OR 2.48) compared to all those aged less than 18 years (OR 2.02). Maternal smoking during pregnancy increased the risk of childhood invasive meningococcal disease in their offspring almost three fold (OR 2.93).

Two studies included in the analysis showed that paternal smoking trebled the risk of invasive meningococcal disease (OR 3.21 and 3.53). However, two other studies assessing paternal smoking failed to show a significant difference. The one study that assessed exposure to SHS from both parents reported an eightfold (OR 8.23) increased risk.

The authors noted that there were approximately 3,070 cases of invasive meningococcal disease among children less than 16 years old in the UK during 2008. They estimated that passive smoking in the home accounts for 20.6 per cent of these, equivalent to approximately 630 extra cases of invasive meningococcal disease each year.

Unemployment increases MI risk
Arch Intern Med (2012) 172(22):1731-1737

Unemployment increases the risk of suffering an acute myocardial infarction (AMI) to a similar extent as smoking, diabetes and hypertension, according to a study of 13,451 US adults aged 51 to 75 years.

After allowing for potential confounders, unemployment was associated with a 35 per cent increase in AMI risk. The risk of suffering an AMI was significantly higher (by 27 per cent) within the first year of unemployment, but not after longer periods.

AMI risk rose as the number of job losses increased: 22 per cent for one loss; 27 per cent for two; 52 per cent for three; and 63 per cent for at least four job losses.

The authors note that the increased AMI risk associated with unemployment was comparable to other major risk factors in the study, including smoking (44 per cent increase), diabetes mellitus (51 per cent) and hypertension (62 per cent).

Back pain lingers
Eur J Pain (2013) 17;5-15

Nurses should not assume that most patients with low back pain spontaneously recover, according to a review of 11 studies. The analysis included prospective studies, with follow-up of at least 12 months, that enrolled patients in primary care who had suffered low back pain for less than three months. The studies used various thresholds and periods (one day to six months) as criteria for being pain free.

Twenty per cent and 33 per cent of patients had recovered within one and three months respectively. However, 65 per cent still reported back pain a year after onset. The proportion of patients reporting pain after a year was 71 per cent in studies that used total absence of pain to define recovery and 57 per cent in those using less stringent criteria.

Based on five studies, the proportion of patients reporting pain decreased by only 1-7 per cent between three and 12 months. The authors suggest that 'there should be more focus on intensive follow-up of patients who have not recovered within the first three months'.