A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010

TL;DR: In this paper, the authors estimated deaths and disability-adjusted life years (DALYs; sum of years lived with disability [YLD] and years of life lost [YLL]) attributable to the independent effects of 67 risk factors and clusters of risk factors for 21 regions in 1990 and 2010.

About: This article is published in The Lancet.The article was published on 2012-12-15 and is currently open access. It has received 9324 citations till now. The article focuses on the topics: Disease burden & Risk factor.

Summary

Convincing evidence

• Evidence based on epidemiological studies showing consistent associations between exposure and disease, with little or no evidence to the contrary.
• The available evidence is based on a substantial number of studies including prospective observational studies and where relevant, randomised controlled trials of sufficient size, duration, and quality showing consistent effects.

Probable evidence

• Evidence based on epidemiological studies showing fairly consistent associations between exposure and disease, but for which there are perceived shortcomings in the available evidence or some evidence to the contrary, which precludes a more definite judgment.
• Shortcomings in the evidence may be any of the following: insufficient duration of trials (or studies); insufficient trials (or studies) available; inadequate sample sizes; or incomplete follow-up.

Possible evidence

• Evidence based mainly on findings from case-control and cross-sectional studies.
• Insufficient randomised controlled trials, observational studies, or non-randomised controlled trials are available.
• Evidence based on non-epidemiological studies, such as clinical and laboratory investigations, is supportive.
• More trials are needed to support the tentative associations, which should be biologically plausible.

Insufficient evidence

• Evidence based on findings of a few studies which are suggestive, but insufficient to establish an association between exposure and disease.
• Burden of disease attributable to individual risk factors are shown sequentially for ease of presentation.

Figures

Figure 1. Burden of disease attributable to 20 leading risk factors in 1990, expressed as a percentage of global disability-adjusted life-years

Table 2

Figure 4. 95% uncertainty intervals for risk factors ranked by global attributable disabilityadjusted life-years, 2010

Table 1 shows the sources of effect sizes per unit of exposure for each risk factor. Some effect sizes were based on meta-analyses of epidemiological studies. For several risk factors without recent systematic reviews or for which evidence had not recently been synthesised, new meta-analyses were done as part of GBD 2010. We used effect sizes that had been adjusted for measured confounders but not for factors along the causal pathway. For example, effect sizes for body-mass index were not adjusted for blood pressure. For some risk–outcome pairs, evidence is only available for the relative risk (RR) of morbidity or mortality. In these cases, we assumed that the reported RR would apply equally to morbidity or mortality, unless evidence suggested a differential effect. For example, studies of ambient particulate matter pollution suggest a smaller effect on incidence of cardio vascular and respiratory disease than on mortality;124–126 the published work on consumption of seafood omega-3 fatty acids suggests an effect on ischaemic heart disease mortality but not on incidence of ischaemic heart disease.90

Figure 3. Global risk factor ranks with 95% UI for all ages and sexes combined in 1990, and 2010, and percentage change

Figure 5. Risk factors ranked by attributable burden of disease, 2010

Figure 6. Attributable burden for each risk factor

Figure 2. Burden of disease attributable to 20 leading risk factors in 2010, expressed as a percentage of global disability-adjusted life-years

Frequently asked questions

Q1. What are the contributions mentioned in the paper "A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990—2010: a systematic analysis for the global burden of disease study 2010 author" ?

Lim, Stephen S, Vos, Umer, Shibuya, Shibaya, Kenji, AdairRohani, Heather, Amann, Markus, Anderson, H Ross, Andrews, Kathryn G, Aryee, Martin, Gmel, Gerhard, Graham, Kathryn, Grainger, Rebecca, Grant, Bridget, Gunnell, David, Gutierrez, Hialy R, Hall, Wayne, Hoek, Hans W, Hogan, Anne-Charlson, H Dean, this paper, Nolla, Nissim, Nelson, Paul K 

Q2. What are the characteristics of the evidence?

Shortcomings in the evidence may be any of the following: insufficient duration of trials (or studies); insufficient trials (or studies) available; inadequate sample sizes; or incomplete follow-up. 

Q3. What is the evidence for a tentative association between exposure and disease?

The available evidence is based on a substantial number of studies including prospective observational studies and where relevant, randomised controlled trials of sufficient size, duration, and quality showing consistent effects. 

Q4. What is the burden of disease attributable to different risk factors?

In reality, the burden attributable to different risks overlaps because of multicausality and because the effects of some risk factors are partly mediated throughLim et al.