What's new in the other journals?

Authors

  • Athol Kent


  • These snippets are extracts from a monthly service called the Journal Article Summary Service. It is a service that summarises all that is new in obstetrics and gynaecology over the preceding month. If you would like to know the details of how to subscribe, please email the editor Athol Kent at atholkent@mweb.co.za or visit the website www.getjass.com.

The dangers of treating breast cancer

Is there a possibility that the treatments of breast cancer can cause harm? Certainly any operation carries some risk, be it a lumpectomy or mastectomy, from the anaesthetic, the surgery or the immobilisation that follows. Chemotherapy is also associated with risks but what about radiotherapy to the breast area and its effects on the organs deep to the skin like the heart and lungs?

The relative risk of death from lung cancer after irradiation is 1.78 and now details are starting to emerge about risks of ischaemic heart disease following radiation treatment (Darby et al. NEJM 2013;368:987–98). Looking at Scandinavian data in women who had their chests irradiated, the researchers found that the greater the dose of irradiation to which she was exposed, the greater the woman's chance of developing ischaemic heart disease and the greater her chances of death. There was a linear increase in major coronary events with each gray (Gy) of exposure.

These findings applied to women who were healthy or had cardiac risk factors when they were initially treated and the effect was present for up to 30 years. The greater the dose (in Gy) and the more cardiac risk factors she had, the greater her danger of acute events or death.

The point being that the treatments of breast cancer are not benign and need to be drawn into the calculations when assessing the harms of screening mammography. If these treatments are carried out on a significant number of people who are not in danger of being harmed by their breast cancer in the first place (those who have been overdiagnosed) then the scales of benefit versus harm from routine mammography may well tip in favour of harm. If so it may be unwise to recommend screening by mammography.

Smoking and preterm births

Smoking, both active and passive, has always been associated with preterm births. The evidence for this has been derived from personal records declared by women who smoked or experienced second-hand smoke in their environment. Now epidemiological data are appearing derived from anti-smoking legislation in Belgium (Cox et al. BMJ 2013;346:f441).

Smoke-free laws were introduced serially in Flanders as follows: 2006 in the workplace, 2007 in restaurants and 2010 in bars serving food. These dates correspond with stepwise drops in preterm delivery rates nationally of between 2 and 3% with final figures around 6.5%—much lower than other developed countries like the USA.

These data strongly support the contention that cigarette smoke, be it first-hand or second-hand, influences rates of preterm births in this particular population group. It is worth noting that in Europe 4 years ago, half of all workers were exposed to passive smoking—by last year the figure had been reduced to one-quarter.

image

Source: Cox et al. BMJ 2013;346:f441.

Autism and folic acid

The autism spectrum of disorders (ASD) stem from a neurodevelopmental dysfunction. Neural tube defects may have similar origins and it has been unequivocally demonstrated that supplementation with folic acid reduces their incidence so it is conceivable that ASD could be similarly affected.

Although placebo-controlled folate trials would be unethical, it is still possible using observational data to relate personal supplementation to no supplement intake and measure ASD presence. This is what a group from Norway did (Surén et al. JAMA 2013;309:570–7) relating reported additional folate consumption to ASD occurrence in children up to a mean age of 6 years. Those who said they had taken folic acid had an autism incidence in their offspring of 0.1% and those who reported no extra folate intake had in incidence of 0.2%.

The researchers say their findings do not establish causality but the results do strengthen the case for folate fortification. It is of interest to recall that Roth et al. (JAMA 2011;306:1566–73) showed that children whose mothers took extra folic acid periconceptually had a lower risk of severe language delay at 3 years.

There may be a genetic susceptibility that links folate intake to neurodevelopmental disorders but until such a risk is established (and all pregnant women's genomes measured!) it is wise to ensure that at least 500 mg of folic acid is taken prepregnancy and in the first trimester by as many women as possible or even is added to oral contraceptive pills. With up to 1% of any population affected by the autism spectrum this is a high priority intervention deserving of public health and obstetric support.

Anti-emetics in early pregnancy

The thalidomide disaster of the 1960s triggered the registration of drugs as fit for purpose and declaration of their safety parameters. It also brought to prominence the teratogenicity of any chemicals ingested at the time of organogenesis plus the need for the utmost caution with prescriptions for nausea and vomiting in pregnancy. Mostly these symptoms begin from 3 weeks of gestation onward and peak towards the end of the first trimester, and are associated with decreased risks of spontaneous miscarriage, so any anti-emetic must prove itself to be safe against a high standard of function and safety.

Ondansetron is a 5-hydroxytryptamine receptor antagonist and the most widely prescribed anti-emetic in the USA in early pregnancy. It is also extensively used in Denmark where they keep records of all prescriptions and have now published its use related to rates of miscarriage, birth defects, stillbirths, low birthweights, early deliveries and small-for-gestational-age infants (Pasternak et al. NEJM 2013;368:814–23).

It was found that none of these parameters of fetal outcomes was adversely affected by the ingestion of ondansetron. As anticipated, the group needing anti-emetics had fewer miscarriages than the population at large but the researchers attribute this to the underlying indication for treatment rather that the medication itself. They caution that their data do not rule out the possibility of adverse effects but do provide reassurance so its use in pregnancy can be summarised as ‘safe so far’.

Vaccination for boys

Australia has led in many domains of medicine including education at undergraduate, postgraduate and continuing professional development levels, rural practice, smoking regulation and, incidentally, in gun control. Having introduced human papillomavirus vaccination for girls in 2007, the government is about to start a programme to immunise all boys this year—the first nation to do so (Brill BMJ 2013;346:f924).

Not only will it protect males from genital warts as well as cancer of the anus, penis and throat but it will contribute to herd immunity of the next generation of Australians, making men incapable of becoming reservoirs of the virus and passing it on to others. Nobody can accuse their government of discriminating against men. Maybe this action will spur law-makers in other countries to follow suit because of moral or possibly legal pressure?

Public health hazards in the United States

One-fifth of Americans smoke cigarettes. In the 1960s 43% smoked so major inroads into tobacco addiction have been made but that still leaves 45 million people puffing away. Half a million of them will die from smoking each year, making smoking the largest preventable course of mortality and morbidity in the USA. It costs the country $100 billion in medical expenses annually and the same amount again in lost productivity.

A peculiarly American tragedy is that of gun violence. The statistics are frightening with guns used to kill over 10 000 citizens each year—more than all US troops killed in Iraq and Afghanistan in the last decade. Add to that, suicides using guns and accidents with guns and the total comes to 30 000 dead per year.

But it appears that they are mesmerised by firearms, so much so that there are more guns than people in the USA and the chances of being killed by a gun are 20 times that in any other developed country (Kuehn JAMA 2013;309:534).

And yet research on this huge public health problem is actively silenced by specific legislation (Kellermann and Rivara JAMA 2013;309:549–50). Other public health studies have contributed to decreases in smoking and motor vehicle accidents giving statistics of which the country is rightly proud (Mozaffarian et al. JAMA 2013;309:551–2). It seems that the gun culture is so tightly woven into the national psyche that not even killing a classroom of children creates sufficient outrage to change the laws.

Ancillary