Examining the figures from the WHO ‘Global Burden of Disease 2010’ Study
If we look again at the data from the WHO Global Burden of Disease 2010 study (‘The global burden’; Whiteford et al., 2015), we can see that anxiety and depressive disorders not only made a significantly disproportionate contribution to the overall burden of disease, but also ranked highest amongst the ‘neurological, substance use and mental disorders’ categories (Whiteford et al., 2015). The prevalence of anxiety and major depressive disorders was also highest in regions with a history of conflict or war (including in North Africa and the Middle East) according to the study (Whiteford et al., 2015). The ‘top 10’ DALYs attributable to mental, neurological and substance use disorders are presented in Table 1.
Disorder | Absolute DALYs (to nearest 100,000) | Proportion of All Cause DALYS % | Proportion of Mental, Neurological and Substance Use DALYS % |
Major depressive disorder | 63,200,000 | 2.5 | 24.5 |
Anxiety disorders | 26,800,000 | 1.1 | 10.4 |
Migraine | 22,400,000 | 0.9 | 8.7 |
Alcohol dependence | 17,700,000 | 0.7 | 6.9 |
Epilepsy | 17,400,000 | 0.7 | 6.8 |
Schizophrenia | 13,600,000 | 0.5 | 5.3 |
Bipolar disorder | 12,900,000 | 0.5 | 5.0 |
Alzheimer’s disease and other dementias | 11,400,000 | 0.5 | 4.4 |
Dysthymia | 11,100,000 | 0.4 | 4.3 |
Opioid dependence | 9,200,000 | 0.4 | 3.6 |
Footnotes
NOTE: DALYS have been aggregated across all countries, gender and age groups.Looking at the data presented in Table 1, what proportion of (i) the total global burden of DALYs and (ii) the burden of mental, neurological and substance use disorders, was attributable to anxiety disorders in 2010?
Anxiety disorders made up 1.1% of all causes of DALYs and 10.4% of the DALYs attributable to mental, neurological and substance use in the 2010 Global Burden of Disease Study, according to the data presented by Whiteford and colleagues (2015).
DALYs attributable to the ‘top 10 burdens’ for mental, neurological and substance use disorders (identified in Table 1) are shown in Table 2, segregated by gender, and standardised for age, comparing figures for 1990 with 2010 (spanning two decades).
Disorder | 1990 Male | 2010 Male | 1990 Female | 2010 Female |
Major depressive disorder | 694.8 | 689.9 | 1171.7 | 1161.2 |
Anxiety disorders | 274.3 | 273.0 | 508.9 | 510.3 |
Migraine | 233.1 | 236.6 | 405.9 | 415.8 |
Alcohol use disorders | 431.0 | 409.9 | 117.2 | 106.0 |
Epilepsy | 261.6 | 269.3 | 226.0 | 232.9 |
Schizophrenia | 230.7 | 223.0 | 187.8 | 180.6 |
Bipolar disorder | 172.0 | 172.1 | 204.6 | 204.8 |
Alzheimer’s disease and other dementias | 125.7 | 155.5 | 153.7 | 178.6 |
Dysthymia | 135.3 | 135.8 | 189.7 | 190.0 |
Opioid use disorders | 139.0 | 184.4 | 63.8 | 78.4 |
Looking at the data presented in Table 2, by what percentage did the DALYs for anxiety disorders change between 1990 and 2010 for (i) males, and (ii) females. What can you conclude from this?
There was a very slight reduction in the DALYs for anxiety disorders for males (of 0.5%), and an equally small percentage increase for females (of 0.3%) between 1990 and 2010. Looking at the figures presented overall, DALYs for anxiety disorders appear to have remained relatively stable over time (i.e. over two decades), although it is not known whether any significant fluctuations occurred during this period.
Take another look at Table 2. This time consider any differences between DALYs for males and females between 1990 and 2010. What can you conclude?
The figure for DALYs attributed to anxiety disorders in females was 1.9 times higher than for males in 1990 and in 2010. The rate of DALYs has remained stable over the two decades, and the female to male ratio of DALYs has remained the same.