Thyroid Research and Practice

EDITORIAL
Year
: 2013  |  Volume : 10  |  Issue : 3  |  Page : 89--90

The global burden of thyroid disease


Sanjay Kalra1, Ambika Gopalakrishnan Unnikrishnan2, Rakesh Sahay3,  
1 Department of Endocrinology, Bharti Hospital and BRIDE, Karnal, Haryana, India
2 Endocrinologist and CEO, Chellaram Diabetes Institute, Bavdhan, Pune, India
3 Osmania Medical College, Hyderabad, India

Correspondence Address:
Sanjay Kalra
Department of Endocrinology, Bharti Hospital and BRIDE, Karnal, Haryana
India




How to cite this article:
Kalra S, Unnikrishnan AG, Sahay R. The global burden of thyroid disease.Thyroid Res Pract 2013;10:89-90


How to cite this URL:
Kalra S, Unnikrishnan AG, Sahay R. The global burden of thyroid disease. Thyroid Res Pract [serial online] 2013 [cited 2022 Aug 12 ];10:89-90
Available from: https://www.thetrp.net/text.asp?2013/10/3/89/116129


Full Text

 Introduction



Thyroid diseases are one of the most prevalent endocrinopathies across the world. While the epidemiology of thyroid illness has been reviewed in Indian journals, [1] the recently published eight-city study on prevalence of thyroid dysfunction and disease. [2] brings thyroidology to center stage once again. In spite of these efforts, thyroid disorders do not seem to be recognized as a major public-health problem. Thyroid Research and Practice recently highlighted the lack of attention paid to thyroid disorders, and advocated inclusion of thyroid diseases in the list of non-communicable disease (NCDs) of public health importance. [3]

In a landmark issue, the Lancet has published a series of articles focusing in the Global Burden of Disease (GBD) 2010. This seminal epidemiological work covers all diseases in all age groups of individuals, from 187 countries, while comparing burden of disease over two decades, from 1990 to 2010. This editorial reviews the global burden of thyroid disease, as reported by GBD. [4],[5],[6],[7]

Thyroid disease is included in both nutritional disease and NCDs. It finds mention in the mortality as well as disability columns of GBD. [4],[5],[6] One can easily analyze the relative importance of thyroid illness by assessing its' standing in the GBD.

 Mortality



Mortality due to thyroid cancer has shown a 50.2% increase from 1990 (24,000, [95% uncertainty interval: 18,000-29,900) to 2010 (36,000 26,000-43,200). This increase is in concordance with changes seen in mortality due to all cancers in general, and NCDs overall (30.0%). [4] In South Asia, thyroid cancer is the 94 th disease in terms of contribution to death, while it ranks 92 nd at global level. The corresponding ranks for women were 90 th and 81 st respectively. [5]

Deaths due to iodine deficiency seem to have shown a disturbing increase, it is surprising to note that iodine deficiency caused 2000 (1700-2400) deaths in 1990, and 3400 (2400-3800) mortalities in 2010, a 67.7% increase. This temporal change is in stark contrast to overall trends reported for nutritional deaths, which show a 30.0% decrease over two decades. [4]

 Sequelae



It is well-known that thyroid disease is not a major cause of mortality. However, it does cause significant sequelae which lead to disability. Goitre due to iodine deficiency contributes to 2.72% of all sequelae of disease worldwide, which is almost similar to that reported for "uncomplicated diabetes mellitus," the most common endocrinopathy (3.30%), and much higher than polycystic ovarian syndrome (1.68% worldwide). As expected there is a strong gender disparity in goitre (2.01% in males and 3.44% in females). These statistics make goiter the 32 nd most prevalent disease sequel in human beings. [6] Goitre due to iodine deficiency and heart failure due to iodine deficiency registered a 29.8% and 33.3% increase in years lost due to disease over the same time period. Mercifully, the sequel of "idiopathic intellectual disability due to iodine deficiency" [how can this be "idiopathic"?] showed a decline of 58.4% over the past two decades, from 271,000 (181,000-386,000) years to 113,000 (73,000-167,000) years. [6]

 Disability



Disability can be measured by assessing disability-associated life years (DALYs). Thyroid cancer caused 836,000 DALYs in 2010, 44.4% up from the 1990 figure of 579,000 DALYs. [7] Iodine deficiency was the 85 th largest contributor to DALYs globally, and the 79 th largest in South Asia, in 2010. It reached 43 rd position in DALY contribution in Central Sub-Saharan Africa. In women, iodine deficiency caused relatively more DALYs, ranking 74 th globally, 70 th in South Asia, and 35 th in Central Sub-Saharan Africa. [5]

Two other yardsticks for measuring disability are known as years of life lost (YLL) and years of life with disability (YLD). Their sum is used to compute DALYs. In the YLL ranking table, thyroid cancer was the 99 th contributor globally, 94 th in South Asia, and 60 th in high-income Asia-Pacific. In women, thyroid cancer was the 93 th highest mortality driver globally, and 87 rd highest in South Asia. [5] Iodine deficiency contributed to 3,181,000 (2,049,000-4,912,000) YLL in 1990, and 3,889,000 (2,468,000-6,136,000) such years in 2010. This was a 22.3% increase. [6]

In South Asia, iodine deficiency ranked all the 33 rd highest contributing disease to years lived with disability YLDs, reaching 29 th place in the female table. To put this statistic in perspective, ischemic heart disease ranked 31 st in the list of diseases contributing to disability in South Asia. [5] Globally, iodine deficiency contributed the 42 nd highest number of YLDs (35 th in women), just behind malaria (#41). [5]

 Conclusion



The public-health importance of thyroid disease cannot be underestimated. While earlier editorials in Indian journals have called for a recognition of this fact, [8] the GBD results once again bring to center stage the need for policy makers to include thyroid disease in the public-health agenda. Thyroidologists, too, need to work to meet the needs and perspectives of people with thyroid dysfunction, while encouraging and accepting patient advocacy as well.

References

1Unnikrishnan AG, Menon UV. Thyroid disorders in India: An epidemiological perspective. Indian J Endocrinol Metab 2011;15:S78-81.
2Unnikrishnan AG, Kalra S, Sahay RK, Bantwal G, John M, Tewari N. Prevalence of hypothyroidism in adults: An epidemiological study in eight cities of India. Indian J Endocr Metab 2013;17:647-52.
3Kalra S, Unnikrishnan AG, Baruah MP. Thyroid: Disorders of a lesser gland. Thyroid Res Pract 2013;10:45-6.
4Lozano R, Naghavi M, Foreman K, Lim S, Shibuya K, Aboyans V, et al. Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: A systematic analysis for the Global Burden of Disease Study 2010 Lancet 2012;380:2095-128.
5GBD Heatmap. Available from: http://www.healthmetricsandevaluation.org/gbd/visualizations/gbd-2010-leading-causes-and-risks-region-heatmap [Last accessed 2012 Dec 16].
6Vos T, Flaxman AD, Naghavi M, Lozano R, Michaud C, Ezzati M, et al. Years lived with disability (YLDs) for 1160 sequelae of 289 diseases and injuries 1990-2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012;380:2163-96.
7Murray CJ, Vos T, Lozano R, Naghavi M, Flaxman AD, Michaud C, et al. Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990-2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012;380:2197-223.
8Sahay R, Kalra S, Magon N. Ensuring an intelligent India: Managing hypothyroidism in pregnancy. Indian J Endocr Metab 2011;15:76-7.