Tag Archives: Director’s Choice – From the Journals

How Many Cigarettes in a Bottle of Wine?

We have talked before about the effects alcohol has on health – ranging from studies showing protective effects against dementia and Alzheimer’s disease,[1] to increasing risk of structural brain changes and cognitive decline.[2] While there have been studies looking at association between alcohol and cancer rates,[3] the general public do not think of cancer when asked to list health risks of drinking (only 13% of adults surveyed were aware of the putative association between alcohol and cancer).[4] A recent paper in the BMC Public Health calculated the lifetime risk of developing alcohol-related cancers and equated this to the risk from smoking.[5]

The authors found that drinking one bottle of wine per week was associated with an increase in the absolute risk of developing cancer during a lifetime of 1.0% in non-smoking men, and 1.4% in non-smoking women. The gender difference was predominantly driven by an increased risk of developing breast cancer. They calculated that this was “equivalent” to a weekly smoking habit of five (for men) or ten (for women) cigarettes.

Although moderate alcohol intake is not equivalent to smoking, there is an argument to increase the level of public health awareness on the risk of cancer from drinking, especially among women. Using cigarettes as an equivalent may help communicate the message of risk more effectively.

— Peter Chilton, Research Fellow

References:

  1. Lilford RJ. So Where Are We Up to With Alcohol And Health? NIHR CLAHRC West Midlands News Blog. 12 January 2018.
  2. Lilford RJ. Alcohol and its Effects. NIHR CLAHRC West Midlands News Blog. 18 August 2017.
  3. Lilford RJ. Oh Dear – Evidence Against Alcohol Accumulates. NIHR CLAHRC West Midlands News Blog. 7 December 2017.
  4. Buykx P, Li J, Gavens L, et al. Public awareness of the link between alcohol and cancer in England in 2015: a population-based survey. BMC Public Health. 2016;16:1194.
  5. Hydes TJ, Burton R, Inskip H, Bellis MA, Sheron N. A comparison of gender-linked population cancer risks between alcohol and tobacco: how many cigarettes are there in a bottle of wine? BMC Public Health. 2019.
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Community Health Insurance Systems: Barriers and Solutions 

Low- and middle-income countries (LMICs) are simply unable to raise sufficient taxation income or sufficient national premiums to provide even a basic form of health coverage for the bulk of their populations. Yet reliance on user fees reduces access compared to a funded system [1] and leads to catastrophic costs. An appealing alternative is voluntary, community risk-sharing schemes. To be effective, such schemes must overcome significant barriers:

  1. Adverse selection whereby people who are already sick or high risk are predisposed to enrol.
  2. Moral hazard whereby people with limited capacity to benefit nevertheless make claims.
  3. Rules to cover those who move or need to exit the scheme.
  4. Lack of trust regarding stewardship of contributions.
  5. Nugatory returns on affordable premiums.

The WHO and UN support volunteer community schemes. Most community schemes have been unsuccessful, achieving minimal coverage. However, notable success has been achieved in some countries. Rwanda stands, out with more than 90% coverage across National and Community schemes.

— Richard Lilford, CLAHRC WM Director

References:

  1. Watson SI, Wroe EB, Dunbar EL, Mukherjee J, Squire SB, Nazimera L, Dullie L, Lilford R. The impact of user fees on health services utilization and infectious disease diagnoses in Neno District, Malawi : a longitudinal, quasi-experimental study.BMC Health Serv Res. 2016;16:595.

Death of a Blogger

The Economist is generally a good read. But it is the obituaries that are especially well written. Recently the obituary made a moving sketch of Dr Mags Portman,[1] proponent of Pre-exposure Prophylaxis for HIV or PrEP. I had not realised how much resistance there had been to adoption of this effective method to reduce risk. I guess there must be some debate about long-term effects on condom use, but the short-term benefit is large at 86% relative risk reduction. Mags was a tireless campaigner and it was tragic to read that her life was cut cruelly short by the disease mesothelioma. Mesothelioma is usually the result of exposure to asbestos. One might have thought that exposure to asbestos was a thing of the past, but Mags believed that she had been exposed while working in a hospital in London. Her life was short but inspiring.

— Richard Lilford, CLAHRC WM Director

Reference:

  1. The Economist. One tablet, taken daily. The Economist. 16 March 2019. p86.

Anal Incontinence is a Risk Even after Caesarean Section

CLAHRC WM associate, Christine MacArthur, has previously done an elegant studies of the antecedents of anal incontinence.[1] She showed that heavier babies and instrumental deliveries increased the risk of this condition. However, she also showed that Caesarean section increases the risk compared to having no baby at all at a given age. Christine’s findings are now corroborated in an enormous Swedish database study of 3.7 million people.[2] The analysis of this study goes even further, finding that simply being a woman increases the risk, compared to being a man. Not that there is much that we can do about this latter finding!

— Richard Lilford, CLAHRC WM Director

References:

  1. MacArthur C, Wilson D, Herbison P, Lancashire RJ, Hagen S, Toozs-Hobson P, Dean N, Glazener C, ProLong study group. Faecal incontinence persisting after childbirth: a 12 year longitudinal study. BJOG. 2013; 120(2): 169-79.
  2. Larsson C, Hedberg CL, Lundgren E, Söderström L. Anal incontinence after caesarean and vaginal delivery in Sweden: a national population-based study. Lancet. 2019; 393: 1233-9.

Update on India’s Massive Public Sanitation Campaign

A recent editorial in the Lancet shows that India has built 100 million toilets since the BJP came to power, partly by providing financial incentives to local communities and through mass awareness campaigns.[1]

While India was only 60% open defecation free in 2015, sanitation coverage in rural India is now 93% and higher still in cities. Toilet usage has increased, but to a lesser extent than coverage. There are ongoing debates about the best type of toilet, especially concerning toilet technologies that treat the sewage on site – so called twin-leach pits. The health effects of this greater coverage do not seem to have been measured, and a survey could be done using the Indian version of the DHS dataset. I think that it will be some time before India experiences the reciprocal of poor hygiene, water and sewage; namely excessive hygiene leading to increased prevalence of atopy.

— Richard Lilford, CLAHRC WM Director

Reference:

  1. Raman VR, Muralidharan A. Closing the loop in India’s sanitation campaign for public health gains. Lancet. 2019; 393: 1184-6.

Now the Journal Nature Attacks P Values

News blog readers know that I am a long standing critic of decision making based on significance tests. ‘Nature’ has now added its voice to the long list of important organisations that have criticised the widespread use of P values to inform decision making.[1] The American Statistical Association has also published a series of articles on the inappropriate significance attached to the traditional limits of statistical significance![2]

‘Nature’ is less clear on what should replace (or I would say augment) the standard significance test. The answer, of course, is obvious – Bayesian statistics, based on informative priors. We are specialising in the use of Bayesian networks to incorporate all salient evidence across causal chains, to estimate parameters and their credible limits.[3]

— Richard Lilford, CLAHRC WM Director

References:

  1. Nature. It’s Time to Talk About Ditching Statistical Significance. Nature. 2019; 567: 283.
  2. Wasserstein RL, Schirm AL, Lazer NA. Moving to a World Beyond “p < 0.05”. Am Stat. 2019; 73(s1): 1-19.
  3. Watson SI & Lilford RJ. Essay 1: Integrating Multiple Sources of Evidence: a Bayesian Perspective. In: Challenges, solutions and future directions in the evaluation of service innovations in health care and public health. Southampton (UK): NIHR Journals Library, 2016.

Gene Sequencing and its Role as a Public Health Tool

The Journal of the American Medical Association recently featured an interesting article on next-generation sequencing as a public health tool.[1] One of the latest technologies, nanopore sequencing, involves threading D/RNA threads through tiny pores and measuring the electric charge signature as the molecule threads through. This is something you really can try at home: a group of Brits took the necessary apparatus out to Guinea in their back-packs during the recent Ebola outbreak. Anyway, the point of this snippet is to advocate the use of molecular technology as an alternative to measuring childhood diarrhoea rates. We hypothesise that these methods will provide a marker of the effectiveness of WASH (Water Sanitation and Hygiene) interventions in low-income countries. Our research [2] suggests that the standard WHO/DHS diarrhoea questionnaire is not accurate – neither specific nor sensitive – as a marker for childhood diarrhoea. Dysentery is too rare. So, we advocate molecular methods to detect the gastrointestinal pathogen load as a marker of environmental contamination. In collaboration with the International Centre for Diarrhoeal Disease Research, Bangladesh we are currently setting up an evaluation of molecular techniques in the Rohingya refugee camp in Cox’s Bazaar, Bangladesh. We hope in time to compare stool micro-biology between high and low risk areas and over time as WASH interventions are rolled out on the ground. We think it will be a better test (both more sensitive and specific) than diarrhoea rates as a measure of population visit.

— Richard Lilford, CLAHRC WM Director

References:

  1. Gwinn M, MacCannell D, Armstrong GL. Next-Generation Sequencing of Infectious Pathogens. JAMA. 2019; 321(9): 893-4.
  2. Watson SI, Sartori J, Uthman O, Lilford RJ. Health effects of sanitation facilities: a Bayesian semiparametric analysis of compositional data. J R Stat Soc Ser C Appl Stat. 2019.

What is Primary Health Care?

In studying health care delivery in informal settlements/slums we have found that people seek health care both in the slum communities and from the local hospital outpatients department. Are those who go to the hospital receiving primary care? The WHO definition is not of any help here because it defines primary care in a way that makes it indistinguishable from secondary care. It is ‘a whole-of-society approach’.[1] How silly; such an approach would include education, industrial policy trade, press freedom and a whole pile more. If a word means everything then it means nothing. It is ‘centred on the needs and preferences of individuals’. Well then, it includes the whole of health care – secondary, tertiary, quaternary, the lot. It ‘addresses the broader determinants of health’. And secondary care can’t do that? And then it goes on about rights without mentioning what happens when not all rights can be met. But one thing is important: at no point does the WHO definition state that primary care cannot be delivered in hospital. This means that service planners have a choice with respect to where they provide services to meet patient demand for reactive care. They can provide it in communities such as informal settlements, or they can strengthen hospital provision. In rich countries provision in communities and close to where people live is affordable and desirable. This might not be the case in urban areas in poor countries where care is usually abysmal according to our near complete systematic review. If people in local communities access care in hospital and are satisfied with it, then ensuring availability of high quality outpatients care may be optimal strategy in low-income cities.

— Richard Lilford, CLAHRC WM Director

Reference:

  1. World Health Organization. Primary health care. 27 February 2019.

Over 40 Years of Test Tube Babies

Yes, it is more than 40 years since the birth of Louise Brown back in 1978. Test tube babies are a little smaller, even allowing for prematurity, than age-matched controls. However, a recent large database study from Finland shows that this difference disappears if the controls are siblings from the same family.[1] The cause of this family effect, is completely unknown.

The results of the Finnish study are broadly reassuring for people having in vitro fertilisation (IVF). However, some of the new methods might have unexpected risks. For example, cryopreservation and thawing of embryos apparently increases the risk of heavier babies, while keeping the embryo out of the body until the blastocyst stage may cause epigenetic changes, with unknown implications for succeeding generations. The corollary is the need for careful prospective studies of these new techniques.

— Richard Lilford, CLAHRC WM Director

Reference:

  1. Goisis A, Remes H, Martikainen P, Klemetti R, Myrskylä M. Medically assisted reproduction and birth outcomes: a within-family analysis using Finnish population registers. Lancet. 2019; 393: 1225-32.

Detecting the Smell of Parkinson’s Disease

Diagnosis of Parkinson’s disease is usually through a variety of physical exercises conducted with specialists, looking for two of three symptoms – a tremor at rest, slowness of movement, muscle stiffness. Diagnosis can also be aided if symptoms are improved after taking levodopa, or through brain scans. However, there is no diagnostic chemical test. At least, not yet. Recently, a team based at the University of Manchester detailed a specific odour found in the sebum from patients with Parkinson’s disease that can be detected.[1]

A few years ago a small study tested a member of the public who claimed to be able to detect a distinctive smell on patients with Parkinson’s disease.[2] Given clothing from 12 individuals (six with Parkinson’s disease, six without) she was correctly able to identify their diagnosis in 11 cases. Amazingly, however, the control subject that she misidentified was later diagnosed with Parkinson’s disease, giving her a 100% accuracy rate. On the basis of this, researchers began to investigate what could cause this distinctive odour, finding that it was present in the sebum (an oily secretion of the body that coats the skin) of patients’ upper backs.

The present study conducted mass spectrometry and olfactory analysis of sebum samples from 64 participants (43 with Parkinson’s disease), which were then combined, revealing a unique volatilome (odour profile) that was associated with Parkinson’s disease. This was then validated using an independent cohort of 31 participants. It is hoped that further studies can help further characterise this volatilome, and eventually led to a panel of biomarkers associated with Parkinson’s disease.

— Peter Chilton, Research Fellow

References:

  1. Trivedi DK, Sinclair E, Xu Y, et al. Discovery of Volatile Biomarkers of Parkinson’s Disease from Sebum. ACS Cent Sci. 2019.
  2. Morgan J. Joy of super smeller: sebum clues for PD diagnostics. Lancet Neurol. 2016; 15(2): 138-9.