Comparing global health claims to data: a look at the 2011 Snooze Report

Global health reports have a propensity to include dramatic pleas for attention. Here’s a formula: if you want to define yourself in global health politics, pick a disease or population, present yourself as the world’s leading advocate for that topic or group, and write reports that declare your issue neglected or misunderstood by ignorant masses paying “too much attention” to “popular” causes of death (“you don’t listen to those mainstream bands, do you?,” says the hipster). Better yet, include striking statistics about your issue that no one can verify, with accompanying photographs of pregnant women or cute children (darker skins preferred).

How do we verify claims made about global health? In this blog post, we put popular claims to the test–by explaining (in plain English) what we call the “Snooze Report”, the annual report revealing actual statistics behind global mortality.

In the 1970’s, the leading causes of death were captured and scrutinized by dozens of nerds at the World Health Organization and other leading health institutions. In recent years, the nerds have been routinely ignored. Global health has burgeoned into an industry of public relations. In Washington D.C. alone, over four dozen lobbying organizations, charities, foundations, think tanks and government offices regard global health as the major focus of their efforts. Some host fundraisers for pediatric vaccines. Others focus on the health of mothers, or diseases in the Sudan. Their press releases, dinner galas, consulting reports, newspaper editorials and magazine spreads serve less to clarify what is happening than to produce a torrent of competing arguments and ideas about what diseases are most important and whose lives are most worthy of saving–their own interpretation of history, fact, experience, morality and “data”.

Under this cloud of information and politics, we seek the answer to a seemingly-simple question: what is actually happening to human health?

A look at Google news over the last month reveals a series of far-fetched claims, such as the idea that Russian mothers die at 400 times the rate of mothers in the US (not true, but it’s about 7 times), that non-communicable cancers are a leading cause of death in sub-Saharan Africa (also not true, they cause about one-twentieth as many deaths as leading infections, and the top two cancers–Kaposi’s sarcoma and cervical cancer–are attributable to infections), and that guinea worm is ravaging the globe (definitely not true, it’s a problem in about 4 countries).

So what are we to believe? Each year, the WHO posts a thick report on its website that contains the answer, but is generally ignored. We fondly call it the Snooze Report (given its ability to cure insomnia), but to most people it is simply referred to as “World Health Statistics”—a title as scintillating as its contents. It’s a dense collection of tables that gets almost no press coverage, probably because its current form is about as informative as a phonebook. But in this week’s EpiAnalysis blog, we take the data from this week’s release of the Report and churn it through our statistical version of a KitchenAid appliance, to bring you the “bottom line” results in a digestible format. We find some striking revelations about who’s dying of what, where they’re dying, and why.

The big trends

First, a disclaimer. Many of the charts and graphs included in this blog post are produced by EpiAnalysis, not by the WHO. We therefore make many conclusions that the WHO doesn’t necessarily endorse. The WHO’s raw data, which were used to produce these figures, can be downloaded here (warning: large file, long wait), but our own analysis of that data is summarized by a few key findings:

[1] Overall life expectancy

The data dramatist Hans Rosling has popularized the idea that life expectancy around the world has generally been improving over the last several decades, so perhaps we should be optimistic:

While life expectancy overall is indeed improving, some countries have surged ahead over the last few decades by having tremendous gains in life expectancy, while a few have actually shifted backwards.

The major improvements appear to be areas that have come out of recent conflict. Eritrea, Liberia and Timor-Leste have gained over fifteen years in average life expectancy since 1990.

By contrast, many countries in sub-Saharan African have faced the largest declines in life expectancy, and it’s no coincidence their losses correspond to mortality rates from HIV.

The major causes of death have been shifting over the years, with non-communicable diseases rising over time, even in low-income countries. The key statistical finding with regard to this change is that the non-communicable disease corresponds strikingly to the availability of tobacco, and to a lesser extent to the availability of alcohol and unhealthy foods. The other major cause of death that’s consistently on a short-list of global mortality is physical injury, particularly road traffic accidents. The UN recently released this list of road deaths around the world, as part of an agenda to make safer cars and streets a public health issue.

[2] Deaths among children

A few key sub-themes emerge when looking at the portion of life expectancy gains or losses that are attributable to children.

In particular, many of the countries where infant mortality has decreased over the last few years are those that have emerged from recent conflicts.

By contrast, those losing ground in terms of infant mortality have faced increasing economic hardship. (In a recent analysis, we looked at how economic growth and increasing democracy affected child and maternal health, and found that they weren’t very effective in the face of ongoing ethnic conflicts.)

One important lesson here is to distinguish prevalence rates (the proportion of the population currently faced with a condition = number currently affected / total population) from the total number of people affected. When looking at child mortality in African countries, some agencies have argued that malnutrition rates are not increasing against the background of recent food price increases. But this claim is based on the prevalence rate of undernutrition. If you look at the actual data, the prevalence rate is decreasing or stable because the overall population size is rising, while the absolute number of underweight children has actually increased (but less so than the population increase). The number of underweight children in sub-Saharan Africa, for example, rose from 24 million in 1990 to 30 million in 2010. So there are actually more undernourished children now than in 1990 (numerator); it’s just that there are even more people overall (denominator), so the prevalence rate appears misleadingly lower.

Among the leading causes of death in children, the two biggest players are those that we have effective interventions for: pneumonia (responsible for 18% of child deaths under 5 years of age) and diarrhea (responsible for another 15%). Despite high diarrhea rates, it remains encouraging that dirty water is moving down the list of key avoidable disease risk factors. The percentage of the world’s population with access to improved drinking-water sources increased from 77% to 87% between 1990 and 2008. Of note, however, 84% of those people remaining with dirty water live in rural regions, which also have the poorest sanitation. There are no clear data regarding the availability of oral rehydration salts in these areas.

[3] Deaths among mothers

Almost all maternal deaths (99%) are occurring in developing countries. There is some good news, however: the number of women dying as a result of complications during pregnancy and childbirth has decreased by 34% – from 546,000 in 1990 to 358,000 in 2008. More women are getting access to contraception (63% of those in a relationship in developing countries), and the proportion of deliveries attended by a skilled birth attendant rose from 58% in 1990 to 68% in 2008. But only about half of mothers get the recommended four antenatal visits during their pregnancy.

An important lesson in interpreting the maternal mortality data is to be cautious about following the overall global trend. While maternal mortality rates are reducing worldwide, the bulk of the decline is being driven by reductions in South-East Asia (where maternal mortality is reducing by 5% per year). The rate of decline in sub-Saharan Africa, by contrast, is only 1.7% per year.

[4] Big infections

A growing number of successes are evident in malaria data. The estimated number of malaria deaths declined from ~1 million in 2000 to 781,000 in 2009, and cases declined from 233 million in 2000 to 225 million in 2009. At least 11 countries experienced >50% reductions in malaria cases and deaths, and Western Europe reported no cases of Plasmodium falciparum malaria.

Tuberculosis, in contrast, seems to lumber on. Renewed by the number of HIV-infected people getting TB, the disease is now only slightly reduced in prevalence because of a slow decline in incidence, but the annual number of new cases is still increasing due to the increase in human population. It was once thought that tuberculosis could be conquered by breaking the “transmission chain”; that is, by treating those infected to prevent secondary infections. But that doesn’t seem to be sufficient in spite of high levels of detection and treatment success, so perhaps primary prevention is in order; statistically, key factors leading to an increased risk of TB infection include malnutrition, exposure to tobacco and other smoke (such as indoor air pollution from stoves), and HIV–but only the last of these is directly addressed by TB control programs to date.

HIV itself is similarly stagnating. The number of people living with HIV increased to 33.3 million people in 2009–23% higher than in 1999. However, more people are surviving the disease due to antiretrovirals, so the prevalence (number of people currently with the disease) is expected to rise. Less than 40% of people with advanced HIV infection, however, have access to antiretrovirals in low- and middle-income nations. The good news is that the annual number of estimated new HIV infections is steadily declining (dropping by almost 20% between 1990 and 2009). New data is emerging to suggest that antiretrovirals can reduce transmission at a population level by lowering the viral load among actively-infected persons.

[5] Big wins against NTDs

Among the neglected tropical diseases (NTDs), some major campaigns have made dramatic progress. Leprosy has reduced by more than 90% since 1985, with >15 million patients cured. In 53 of the 89 countries with endemic lymphatic filariasis, mass treatment programs have been initiated and treatment rates have increased from 10 million people in 2000 to 546 million in 2007. The number of new cases of dracunculiasis has also fallen from 892 055 in 12 disease-endemic countries to 3190 in four countries (>99% reduction). The notable exception to this trend is dengue, which appears to have increased and spread to five of the six WHO regions–perhaps, some hypothesize, because of climate change.

Addressing the burden

One theme that emerges from these statistics is that many of the leading causes of death are not only issues amenable to broad population-level health interventions like tobacco control or sewage system development, but also increasingly to interventions that can be performed in a doctor’s office or health post, like antibiotic therapy and antenatal care. A section of the Snooze Report provides some insights into how hamstrung some clinics are in providing this treatment. In more than 40 mainly low-income and middle-income countries, key generic medicines are available in only 42% of health facilities in the public sector and 64% of facilities in the private sector. In the private sphere, those generic medicines cost on average 630% more than their international reference price–meaning that patients are getting charged more than they would have if public sector facilities were able to carry the needed supply.

The Report overall calls for some optimism: in a global sense, the world is getting healthier. But the fact that so much of the improvement is being driven by a few countries, particularly those in Asia, while much of sub-Saharan Africa still falls behind, is a reminder that Africa is not necessarily receiving “too much attention”. As population sizes grow, prevalence rates may decline on paper and in our minds, but this stands in contrast to growing lines at clinics and hospitals, or growing lines on death registers. What the World Statistics Report provides is a reality check for both our most optimistic and pessimistic claims (from the declines in child and maternal mortality to the neglect of NTDs), and a broad framework for the more detailed ongoing work of global health agencies attempting to bite-off their own portion of the global disease burden.

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