Send letter to journal:
Re: Lung function and low birth weight

Dear Editor

At the risk of being accused of raising a trivial issue, I would simply like to ask authors to quote accurately from references within their articles. I am concerned in particular about the study of the respiratory outcome of children of very low birthweight reported recently by Anand and colleagues.[1] They quote the results of a similar study of younger children, which we reported some years ago in this journal.[2] Interestingly, the results were similar, suggesting that the functional outcome for low birth weight children was independent of respiratory support in the neonatal period, and independent of IUGR (“small for dates” in our rather old fashioned terminology). We found a highly significant linear relationship between the FEV 0.75 at the age of 7, and birthweight.

Anand and colleagues quote our study as showing “significant differences between those who received ventilatory support and those who did not”. This contradicts even a selected reading of the final line of our abstract, which stated that “the absence of an association between neonatal oxygen score or mechanical ventilation and childhood lung function suggests that the long term effect of neonatal respiratory treatment is small compared with that of low birth weight…..”. It is gratifying that the two studies come to similar conclusions, but disappointing to be utterly misquoted.

References

(1) D Anand, C J Stevenson, C R West, P O D. Pharoah. Lung function and respiratory health in adolescents of very low birth weight. Arch Dis Child 2003;88:135-138.

(2) K N Chan, C M Noble-Jamieson, A Elliman, E M Bryan, M Silverman. Lung function in children of low birth weight. Arch Dis Child 1989; 64:1284-1293.

Send letter to journal:
Re: Lung function and respiratory health in adolescents of very low birth weight

Dear Editor

We thank Professor Silverman for his comments on our paper.

In the Discussion section of our paper, we inadvertently stated ‘ventilatory support’ instead of ‘respiratory support’ and this may have accounted for some of the misunderstanding that arose. Our definition of respiratory support was any form of supplementary oxygen, continuous positive airway pressure or mechanical ventilation [1] and we grouped our index cohort into those who had or had not received such support. We found no statistically significant differences in respiratory function between the two groups. In contrast, Professor Silverman, in the text of his article states ‘low birth weight children who received neonatal respiratory treatment had poorer airway function than those who did not (p<0.01).[2] It is this difference in observation between the two studies to which we wished to draw attention.

Professor Silverman also states there was ‘no difference between those who received oxygen treatment alone and those who received mechanical ventilation in addition’. We were unable to make this comparison.

References

(1) D Anand, C J Stevenson, C R West, P O D. Pharoah. Lung function and respiratory health in adolescents of very low birth weight. Arch Dis Child 2003;88:135-138.

(2) K N Chan, C M Noble-Jamieson, A Elliman, E M Bryan, M Silverman. Lung function in children of low birth weight. Arch Dis Child 1989; 64:1284-1293.

Send letter to journal:
Re: Lung function and low birth weight

Dear Editor

Dr Anand still refuses to quote our work accurately there was of course a difference between those preterm children who had received ventilatory support and those who had not, but this difference was almost entirely explained, in multiple regression, by birthweight. Hence their conclusions largely support our 1989 study.

Yours faithfully

Professor Michael Silverman
Department of Child Health
Faculty of Medicine & Biological Sciences
Robert Kilpatrick Clinical Sciences Building
Leicester Royal Infirmary