There is considerable evidence that cryptorchidism (undescended testicle) is associated with malignancy, as well as infertility, but the reasons for this remain unclear. In a paper in this week's BMJ, doctors at the London School of Hygiene and Tropical Medicine, and the Norris Cancer Centre, Los Angles, report that their study of the records of 1075 boys treated for cryptorchidism at Great Ormond Street Hospital, London, indicates that biopsy is the strongest risk for testicular cancer.

The authors say that, because of the risks of infertility and malignancy to boys who have surgical treatment for undescended testes late in childhood, there is an increasing tendency to carry out the operation early in life. However, they found no benefit to having surgery at young ages, and say that it is uncertain whether early intervention can avoid these risks.

The largest risk was in relation to biopsy, although this could be due to the fact that this had been carried out because the testes had characteristics which were risk factors for malignancy. But the damage caused to the testis by biopsy could also be a factor, say the authors, although they point out that, in this case, this may have been due to the open biopsy procedure used at the time. Animal studies have shown that this procedure causes widespread damage and it is known to cause granu

There are instances in which organs other than the testis where trauma appears to lead to cancer, say the authors, who call for further investigation into the possibility that biopsy might cause malignancy.

Contact:
Professor Tony Swerdlow

London School of Hygiene and Tropical Medicine

Sleeping on a mattress previously used by another child or adult may increase the risk of sudden infant death syndrome (SIDS, or cot death), says a paper in this week's BMJ. Doctors from the Scottish Cot Death Trust and University of Edinburgh Statistics Unit report that this was an unexpected finding which needs further study.

The authors confirmed a number of risk factors for SIDS, the most important of which was smoking. Two thirds of the cases of the syndrome might be avoided if the mother did not smoke during pregnancy, they say. Sleeping position was also important. Sleeping on the side was more risky than on the back, and parents should be advised to put babies down to sleep only on their backs, say the authors.

The results from the mattress analysis showed that there is an increased risk of some kind, regardless of other factors, although the risk was not established when the mattress was completely covered by PVC. "Our findings therefore lend no support to the hypothesis that household fungi interact with fire retardant chemicals in the plastic covering of cot mattresses and release toxic gases, which in turn cause sudden infant death", say the authors.

Contact:
Hazel Brooke

Scottish Cot Death Trust

Tel: 0141 357 3946
Fax: 0141 334 1376

A study of 1321 mothers and their children in rural Tamil Nadu, South India, shows excess neonatal mortality among girls, constituting about one third of the perinatal mortality rate. This seems to be linked to a preference for sons, and should be tackled by a holistic approach rather than biomedical intervention, say the authors of the paper in this week's BMJ.

In the area of Tamil Nadu, women have a controlled reproductive pattern with an average of 2.3 pregnancies and 1.8 living children, and the sex ratio at birth is 107 boys to 100 girls. "Girls had a significantly higher risk of neonatal mortality than boys, and this was even more pronounced among girls born to multiparous women without living sons. This indicates that other causes of death .... should be considered", say the authors. "If perinatal mortality is to decline further, a holistic

Contact:
Dr Birgitte Nielsen

Aarhus University Hospital,
Denmark

"Diet affects the health of socially disadvantaged people from the cradle to the grave", says a paper in this week's BMJ, "but the potential for health gain through improved diet is enormous."

The poorer health of people in the lower socioeconomic groups is well recognised, but its origins are complex, say the authors. The annual national food survey of 7000 British households shows that, compared with the highest income group (A), low income groups D and E2 consume more milk (but less semi-skimmed milk), meat and high fat meat products, fats. Sugars and preserves, potatoes and cereals. They consume fewer fresh vegetables, fruit and higher fibre products such as brown and wholewhe

Thus, say the authors, their intake of nutrients is lower, and markedly so for calcium, iron, magnesium, folate and other B vitamins, and especially vitamin C. Over the past 15 years food consumption and energy intakes have fallen, refecting an increasingly sedentary lifestyle - but as energy intakes decline, diets need to become more nutrient-dense to compensate, say the authors.

They claim that there is scope for enormous health gain if a diet rich in vegetables, fruit, unrefined cereal, fish, and small quantities of quality vegetable oils could be more accessible to poor people. "A poor quality diet, physical inactivity and smoking are a lethal triad for the lower social classes, leading to an intergenerational spiral of ill health and handicap", they conclude.

Contact:
Dr Ann Ralph

Rowett Research Institute,
Aberdeen,
Scotland

By the end of the year, says Delamothe, the full text of Minerva will be joined on the BMJ web site by the entire text of the current issue.

How to read a paper, by Trisha Greenhalgh, will be of use to anyone who needs to assess a research paper for scientific validity, put it into context, and understand its relevance. Available from the BMJ Publishing Group at £14.95, the book uses practical examples to cover such subjects as statistics for the non-statistician, papers which report drug trials, systematic reviews and meta-analyses, and economic analyses.

Contact:
Dr Tony Delamothe
Web editor

BMJ
London WC1H 9JR