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(1) Drug abuse accounts for a third of the deaths behind Scotland’s higher mortality rate
(2) Does too much sun cause melanoma?
(3) Giving an additional early vaccination may reduce measles outbreaks in low income countries
(4) Population policy needed for the UK in order to combat climate change

(1) Drug abuse accounts for a third of the deaths behind Scotland's higher mortality rate
(Contribution of problem drug users' deaths to excess mortality in Scotland: secondary analysis of cohort study)
http://www.bmj.com/cgi/content/abstract/337/jul22_2/a478

Drug abuse accounts for a third of the deaths behind Scotland's higher mortality rate, according to a study published on bmj.com today.

Death rates in Scotland are higher than in England and Wales and the difference between the nations is increasing. Traditionally this has been blamed on the higher levels of deprivation in Scotland. Yet over half the difference between Scottish and English deaths cannot be accounted for by higher levels of deprivation. This puzzling "excess" of Scottish deaths has become referred to as the "Scottish effect."

Professor Bloor and colleagues from the University of Glasgow, analysed how many of these unaccounted-for deaths were the result of drug abuse.

They say that the published data on "drug related deaths" in Scotland is properly and purposely restrictive because only deaths which are a direct result of the pharmacological effect of taking an illegal drug i.e. an overdose, are counted. This, they argue, inadvertently hides a much wider problem of deaths linked to drug taking such as blood borne infections, suicide and violent assaults.

In order to estimate the number of deaths in a population of drug users they matched mortality data from the General Register Office for Scotland with participants in a study on Drug Outcomes Research in Scotland (DORIS). As part of that study, 1033 problem drug users who started a new bout of treatment in one of 33 drug treatment agencies across Scotland were interviewed between 2001 and 2002. They were followed up between 2004 and 2005.

Of those who didn't have follow-up interviews the researchers found 38 had died. Only 22, just over half, of those deaths had been recorded as drug-related. Of the other deaths, six were suicides (including three overdoses from medication such as paracetamol), three were due to an "infection associated with drug abuse", two were due to assaults, one was due to "alcoholic liver disease" and one due to exposure.

Previous work has shown that 1.84% of the Scottish population had a problem with drug abuse, compared to 0.99% in England.

Applying the rate of deaths of drug users in the DORIS study to the wider population of drug users in Scotland, allowed the authors to estimate that 32% of Scotland's excess mortality rate is due to the greater prevalence of problem drug abuse in the country.

Compared to smoking, excess drinking, or lack of exercise, relatively few people have a problem with drug abuse. However, the risk of death is high-drug users in the DORIS study were found to be 12 times as likely to die as someone from the general population.

Professor Bloor and colleagues conclude that successful public health campaigns to reduce the number of people taking drugs "would have a strong impact on overall mortality in both Scotland and England."

Contacts:
Michael Bloor, Centre for Drug Misuse Research, University of Glasgow, Scotland
Email: m.bloor@lbss.gla.ac.uk

(2) Does too much sun cause melanoma?
(Head to Head: Is sun exposure a major cause of melanoma?)
Yes:http://www.bmj.com/cgi/content/extract/337/jul22_2/a763
No:http://www.bmj.com/cgi/content/extract/337/jul22_2/a764

We are continuously bombarded with messages about the dangers of too much sun and the increased risk of melanoma (the less common and deadliest form of skin cancer), but are these dangers real, or is staying out of the sun causing us more harm than good?

Two experts debate the issue on BMJ.com today.

Sam Shuster, a consultant dermatologist at Norfolk and Norwich University Hospital, says that sun exposure is the major cause of the common forms of skin cancer, which are all virtually benign, but not the rarer, truly malignant melanoma.

Shuster says that the common skin cancers develop in pale, sun exposed skin and are less frequent in people who avoid the sun and use protection. In contrast, melanoma is related to ethnicity rather than pigmentation and in 75% of cases occurs on relatively unexposed sites, especially on the feet of Africans. Melanoma occurrence decreases with greater sun exposure and can be increased by sunscreens, while sun bed exposure has a small inconsistent effect. Therefore, he concludes, any causative effect of ultraviolet light on melanoma can only be minimal.

There is good evidence that the reported increase in melanoma incidence is an artefact caused by the incorrect classification of benign naevi as malignant melanomas, this, he argues, explains why melanoma mortality has changed little despite the great increase in alleged incidence.

He recognises that ultraviolet light causes the common, mainly benign skin cancers and, like smoking, wrinkles the skin. But he says, this is not a good enough reason for a blanket ban and we have to strike a balance with the sun's many other effects on health - from psychological and immunological, to the synthesis of vitamin D essential for bones and apparent protection against many major organ cancers.

But Professor Scott Menzies, from the University of Sydney at the Sydney Melanoma Diagnostic Centre, argues that melanoma is far more common on body sites receiving more sun exposure and in people of races who tend to burn rather than tan.

According to Menzies, there is considerable evidence that intermittent sun exposure and sunburn are strong independent indicators of the risk of developing melanoma in white populations.

He argues that there is a clear association between increasing cases of melanoma and increasing environmental ultraviolet light. Genetic evidence is also supportive, he claims, with the major genes causing melanoma showing ultraviolet light "signature" mutations, while people deficient in repairing ultraviolet light genetic damage have a 1000 times greater risk of developing the disease.

He points to data from Australia which shows that cases of melanoma among young adults fell between 1983 and 1996 and this coincided with strong public health messages to use sun protection.

When you examine the geographical, sun exposure and genetic evidence together, sun exposure is clearly a major cause of melanoma, he concludes.

Contacts:
Sam Shuster, Department of Dermatology, Norfolk and Norwich University Hospital, Norwich, UK
Email: sam@shuster.eclipse.co.uk
Scott Menzies, University of Sydney, Sydney Melanoma Diagnostic Centre, Royal Prince Alfred Hospital, NSW, Australia
Email: scott.menzies@email.cs.nsw.gov.au

(3) Giving an additional early vaccination may reduce measles outbreaks
(Protective efficacy of standard Edmonston-Zagreb vaccination in infants aged 4.5 months: randomised controlled trial)
http://www.bmj.com/cgi/content/abstract/337/jul24_2/a661
(Editorial: Early vaccination against measles in developing countries)
http://www.bmj.com/cgi/content/extract/337/jul24_2/a406

Outbreaks of measles in developing countries may be reduced by vaccinating infants at 4.5 months of age as well as at the World Health Organization's recommended routine vaccination at 9 months, according to a study published on BMJ.com today.

These findings should lead to reconsideration of the policy for vaccination during measles outbreaks and in humanitarian emergencies, say the authors.

Maternal antibodies protect against measles during the first months of life and infants routinely receive their first vaccination between 9 and 15 months to coincide with when these maternal antibodies are lost. This vaccination policy was based on children born to naturally infected mothers, but measles vaccination campaigns over the past 20-25 years in low income countries have resulted in many mothers being immunised and transferring only half the maternal measles antibodies as naturally immune mothers.

Similarly, HIV positive mothers transfer a smaller number of antibodies than HIV negative mothers and HIV positive children also lose their protective maternal antibodies early. As a result, a new group of children now exist who may lose their protection by 3 to 5 months of age and there may well be a need to provide measles vaccination at an earlier age.

A measles outbreak in Guinea-Bissau in Africa offered Professor Peter Aaby and colleagues a unique opportunity to assess the protective effect of earlier vaccination at 4.5 months. 1333 infants were randomised to receive either measles vaccination at 4.5 months of age (441) or nothing (892). At 9 months of age all children received a measles vaccination. Blood samples were collected to assess levels of maternal antibodies levels against measles at 4.5, 9, and 24 months of age in the early vaccination group and at 9, 18, and 24 months of age in the control group.

The researchers found that early vaccination at 4.5 months of age offered more than 90% protection against measles infection and 100% protection against measles hospitalisation.

Prior to the initial vaccination at 4.5 months of age only 28% of the children had protective levels of maternal antibodies against measles. After this early vaccination 92% had measles antibodies at 9 months of age.

The researchers found that children vaccinated at 4.5 months and 9 months were better protected than those vaccinated only at 9 months. The monthly incidence of measles was 0.7% in the children who received two doses and 3.1% in the children who received one dose at 9 months.

"If elimination of measles is planned it will be necessary in Africa to immunise as early as possible for many years", conclude the authors.

These findings offer policymakers potential alternative vaccination strategies, but research is required to determine the possible immunosuppressive effect from live virus measles vaccines on other vaccine responses when given in early infancy, say Dr Hélène Broutin and Dr Mark A Miller from the National Institutes of Health, in an accompanying editorial.

"The current goal to achieve high vaccine coverage should not be separated from the need for more timely vaccination, especially in developing countries…[but] earlier measles vaccination should not substitute for the dose given to infants at ages 9-15 months, which increases overall immunity in the population", they conclude.

Contacts:
Peter Aaby, Bandim Health Project, Indepth Network, Bissau, Guinea-Bissau, Africa
Email: p.aaby@bandim.org
Mark A Miller and Hélène Broutin, Division of International Epidemiology and Population Studies, Fogarty International Center, National Institutes of Health, USA
Email: millemar@mail.nih.gov
broutinh@mail.nih.gov

(4) Population policy needed for the UK in order to combat climate change
(Editorial: Population growth and climate change)
http://www.bmj.com/cgi/content/extract/337/jul24_2/a576

The biggest contribution UK couples can make to combating climate change would be to have only two children or at least have one less than they first intended, argues an editorial published on BMJ.com today.

Family planning and reproductive health expert Professor John Guillebaud and Dr Pip Hayes, a GP from Exeter, call on UK doctors to break their silence on the links between population, family planning and climate change. They point to a calculation by the Optimum Population Trust that "each new UK birth will be responsible for 160 times more greenhouse gas emissions … than a new birth in Ethiopia."

As far back as 1949 The Royal Commission on Population stated "We have no hesitation in recommending…a replacement size of family in Great Britain" and called for a "continuous watch over population trends and their bearing on national policies". Yet the UK continues to this day without any defined population policy.

With world population exceeding 6700 million, Guillebaud and Hayes say that humankind's consumption of fuel, water and food is exceeding supply. They add that the 79 million annual increase in global population equates, somewhere in the world, to a huge new city for 1.5 million appearing each week.

Providing contraception does not need to be coercive, they argue, asserting strongly that governments do not have to follow the example of India in the 1970s or currently China.

Many countries, including Costa Rica, Sri Lanka and Thailand, have reduced their fertility rates by meeting women's unmet fertility needs and choices. The authors claim that with half of pregnancies worldwide being unplanned, no-one needs to be forced to use contraception, what they need is information and access.

The reality is, say the authors, that most women in low resource settings want to be able to plan fewer children than they have, but are prevented from doing so because of many barriers. These include lack of empowerment and abuse of their rights by husbands, partners, mothers in law, religious authorities or sometimes even contraceptive providers. The evidence shows that the demand for contraception increases when it is made available and accessible.

Professor Guillebaud and Dr Hayes call on doctors to help eradicate the many myths and non-evidence based medical rules that deny women access to family planning.

Contact:
John Guillebaud, University College, London, UK
Email: j.guillebaud@lineone.net

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