Public health

Emeritus Prof Simon Chapman AO
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Using prescription drugs or over-the-counter products like gums, mints or patches won’t increase your chances of quitting smoking a year later, according to a new study.The US researchers followed two groups of people 2002/03 and 2010/11 and found at the end of the 12-month period, those using varenicline (sold in Australia as Champix), bupropion (Zyban), or nicotine-replacement therapy (gums, mints or patches) were no more likely to have quit smoking for 30 days or more than those who didn’t use these drugs.
Read more – Weekly Dose: Champix’s effectiveness is questionable and safety record is concerning

Evidence based smoking cessation?

We’re told the best way to quit smoking is to use an “evidence-based” method: a strategy supported by high-quality research evidence. And for the last 30 or so years, this has been nicotine-replacement therapy, bupropion (Zyban) and varenicline (Champix), which claim to increase (and sometimes double) your chance of success.In the hierarchy of evidence, the lowest form is anecdote or case studies (“I smoked for 20 years, then an alternative therapist sprinkled magic powder on me, and the next day I stopped smoking!”). These cannot withstand the most elementary critical appraisal, starting with the basic question of how many similar smokers sprinkled with the powder kept smoking and how many who went nowhere it also stopped smoking.Far higher up the evidence pyramid is the double-blinded, randomised controlled trial (RCTs). In these, both the person taking the treatment and those delivering it are unware of who is taking the active drug and who is taking the comparison placebo or comparison drug. All enrolled in RCTs are randomly allocated to the active or placebo/comparison groups. The numbers of participants are sufficiently large enough to allow for an outcome to be declared statistically significant (or not) above a chance finding.
Read more – Randomised control trials: what makes them the gold standard in medical research?
Some have tried to dismiss earlier findings about the poor performance of nicotine-replacement therapy by emphasising “indication bias”. In the real world, those who opt to use medications to try to quit are likely to be more intractable smokers, more highly addicted to nicotine, and with histories of failure at quitting unaided. No one should therefore be surprised if they fail more often than those who try to quit on their own.In this new study, this issue was anticipated and all smokers were assessed by what the study authors called a “propensity to quit” score. This score accounts for factors such as smoking intensity, nicotine dependence, their quitting history, self-efficacy to quit, and whether they lived in a smoke-free home where quitting would likely be more supported.In the analysis, those who tried to quit with drugs and those who didn’t were matched on this propensity score, so “like with like” could be compared in the analysis. The findings held even when these “propensity” to quit factors were taken into account.

RCTs are very different to real world use

Critics have long pointed out that RCTs have many features which make them a pale shadow of how drugs are used in the real world.RCTs often exclude people with mental illness, poor English, and no fixed address. Excluding hard-to-reach and treat participants is likely to produce more flattering results.In the real world, people are not paid or otherwise incentivised to keep taking the drugs across the full period of the trial, so compliance is almost always far lower.In the real world, people do not get reminder calls, texts or visits from researchers highly motivated to minimise trial drop-out. There is no “Hawthorne effect”: when trial involvement and the attention paid to participants alters the outcomes.Nicotine-addicted people generally know very quickly if they have been allocated to the placebo arm in NRT trials because their brains feel deprived of nicotine. They invariably experience unpleasant symptoms. Knowing they have been allocated to the placebo undermines the integrity of the trial because it is important participants believe the drug might be effective.Large, real world studies like the one just published, which assess long-term success, not just end-of-treatment or short-term results, are therefore of most importance in assessing effectiveness. These new data ought to cause such rhetoric to cool right down.As for the evidence on e-cigarettes in quitting, neither the US Preventive Health Services Task Force, nor the UK’s National Institute for Health and Care Excellence or Australia’s National Health and Medical Research Council, have endorsed e-cigarettes as an effective way of quitting smoking.
Read more: Want to quit smoking? Switching to e-cigarettes no advantage
Quitting smoking is the single most important thing anyone can do to reduce the likelihood they will get heart or lung disease, and a whole string of cancers.It has been in the clear interests of the pharmaceutical and, more recently, the vaping (e-cigarette) industries, to promote the notion that anyone who tries to quit alone is the equivalent of someone with pneumonia refusing antibiotics. Hundreds of millions around the world have quit smoking without using any pharmaceutical intervention.Before nicotine-replacement therapies became available in the 1980s, many millions of smokers successfully quit smoking without using any drug or nicotine substitute. The same still happens today: most ex-smokers quit by going cold turkey.The ConversationThe problem is, in recent years, the government has moth-balled the national quit campaign, the megaphone for promoting this very positive message. Commercial interests are now commodifying something millions have always done for themselves.Simon Chapman, Emeritus Professor in Public Health, University of SydneyThis article was originally published on The Conversation. Read the original article.
Dr Linda Calabresi
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All pregnant women who are smokers should be offered nicotine replacement therapy (NRT) as an option to help them quit, Australian researchers say.In a review published in the MJA, authors said that even though there was a general acknowledgement that there was no firm evidence that proved NRT was safe or effective in pregnancy, all the current guidelines recommend its use for women who couldn’t quit without medication.In a nutshell, NRT is safer than smoking, and smoking during pregnancy is the most important preventable risk factor for poor maternal and infant health outcomes, they said.Despite this, there appears a reluctance among doctors, both here and around the world to prescribe the therapy to pregnant women.The researchers cited a recent survey of Australian GPs and obstetricians that found one in four said they never prescribed NRT in pregnancy.One possible reason for this reluctance, they suggest is the caveats and cautions included in many of the guidelines. Phrases such as ‘only if women are motivated’, ‘only give out two weeks’ supply’ and ‘under close supervision’ hardly inspire confidence in the safety of the therapy.“Ambiguous messages may be contributing to the low NRT prescribing rates and, therefore, it is important to provide a clear practical message to health practitioners and women,” they said.After analysing the various guidelines, the researchers suggest using the strength of the urge to smoke as well as how frequently the urge to smoke occurs to help assess when a woman needs to start or increase the dose of their NRT.“The most important guidance for NRT in pregnancy is to use the lowest possible dose that is effective. However, to be effective, women should be instructed to use as much as needed to deal with cravings,” they advised.They also recommend women be encouraged to use NRT for at least 12 weeks or longer if required to ensure they don’t relapse.All smokers who are pregnant should be told “There is nothing better for you and your baby’s health than to quit smoking.”Ref:MJA  Online first 4.12.17 doi:10.5694/mja17.00446

Diana Lucia
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Abstaining from alcohol during preconception and pregnancy is usually considered to be the woman’s responsibility. The main concern surrounding alcohol exposure during pregnancy often relates to well-established evidence of newborns developing a range of behavioural, physical and cognitive disabilities later in life.But recent research is also pointing to a link between alcohol and poor sperm development, meaning the onus is on expectant fathers too. A myriad of studies are showing biological fathers who drink alcohol may have a significant role in causing health problems in their children.Studies are showing paternal alcohol consumption has negative effects at all levels of the male reproductive system. This is as well as altered neurological, behavioural and biochemical outcomes in subsequent generations.
Read more: Hey dad, your health affects your baby’s well-being too

Men and risky drinking

In Australia, men consume alcohol at high or risky levels on a regular basis. National health guidelines recommend no more than two standard drinks on any day.According to the National Alcohol and Drug Knowledgebase, Australian men usually drink more alcohol than women.Data has shown males are twice more likely than females to consume more than two standard drinks per day on average over a 12-month period (24% compared with 9.8%). And about a third of males said they exceeded the guideline not to drink more than five standard drinks on a single occasion on a monthly basis.

Booze and swimmers

These figures are alarming given the compelling evidence about the impact of excessive, chronic or binge alcohol consumption on sperm, semen quality, fertility and child health.
Read more: Dads get postnatal depression too
Animal studies have shown a single dose of ethanol into the stomach lining (equivalent to a human binge drinking) induces damage to the testis, damaging the cells essential for sperm formation.In another experimental study, sperm health and fertility was assessed in male rats after administration of alcohol into the stomach for ten weeks. The results confirmed alcohol significantly reduced sperm concentration and the ability of the sperm to move properly. And none of the rats exposed to alcohol fertilised the females, despite confirmation of successful mating.A myriad of other non-human studies have also shown similar results, suggesting ethanol has the ability to damage sperm and fertility.Studies in humans have also supported these findings. A recent study of 1,221 young Danish men (18-28 years of age) tracked alcohol consumption in the week preceding the study to determine its effects on semen quality (volume, concentration, total count, and shape).The results showed sperm concentration, total sperm count and percentage of sperm with normal shape got worse the more the men drank. This association was observed in men reporting at least five units of alcohol in a typical week, but was most pronounced for men with a typical intake of more than 25 units a week. This suggests even modest habitual alcohol consumption of more than five units a week can negatively affect semen quality.
Read more: Mother knows best? Fathers missing in research about kids
A recent review of studies and meta-analysis of population data replicated many of these findings. The main results showed daily alcohol intake at moderate to high levels had a detrimental effect on semen volume and normal shape.

The effects on children

Limited studies have tracked the drinking patterns of fathers around the time of conception and subsequent health outcomes of the child. But rodent models have shown changes in offspring weight and development, learning and activity, anxiety related behaviours and molecular and physiological effects.A study also reported the women whose partners consumed ten or more drinks per week prior to conception had two to five times increased risk of miscarriage compared to those whose partners did not drink during preconception.Other studies provide some preliminary evidence that paternal preconception alcohol use is associated with acute leukemia at high-level use, heart malformation with daily use, microcephaly with low to moderate use, and effects in relation to fetal growth and mild cognitive impairments.

How can alcohol affect kids before they’re born?

The exact mechanism of how alcohol alters developing sperm and the later health outcomes of the foetus is still not yet fully understood. It’s been suggested alcohol can change the micro-environment within the testes, altering the development and maturation of the sperm.It’s also been suggested alcohol can influence sperm by creating genetic alterations and epigenetic marks. This means changes to gene expression occur without changes to the underlying DNA sequence. These epigenetic marks can be transferred at the time of fertilisation. This can subsequently alter the molecular makeup of the early embryo, leading to alterations in foetal development and the potential to impair offspring health.The biggest hurdle for researchers now is continuing to translate findings from the basic sciences to more sophisticated research in humans. The next stage is to identify patterns of alcohol use by men during the preconception period on foetal and childhood outcomes in the Australian context.The ConversationBut most importantly we need to realise decisions about alcohol use during the preconception period are not the sole responsibility of women. We need to be talking to men about these issues to ensure healthy outcomes for the baby.Diana Lucia, PhD candidate, Neuroscience, School of Biomedical Sciences, The University of Queensland and Karen Moritz, Professor, The Univeristy of Queensland, The University of QueenslandThis article was originally published on The Conversation. Read the original article.