How COVID-19 Affected Newly Discovered Cases of COPD in Three Industrial Regions of Kazakhstan

Introduction

COPD risk factors are smoking, industrial dust, fumes and other aerosolic microparticles irritating epithelium of bronchial tree [1]. Traditionally all industries are located in the Nothern (coal mining), Western (oils and gas) and few in the South (certain metals like, lead, plants and phosphor-organic fertilizers producers) [2-4]. Over the past 10 years, the incidence of COPD has been declining dynamically in the Republic of Kazakhstan. High incidence was observed in 2016, at 386.2 cases per 100,000 population. The growth rate in 2022 was 80.62% compared to 2002 (Table 1).

	The incidence rate of chronic and unspecified bronchitis and emphysema, registered for the first time in life, per 100 thousand population	Visibility index, %
2002	311.8	100
2003	285.9	91,69
2004	293.2	94,03
2005	322.2	103,3
2006	335.0	107,4
2007	321.4	103,07
2008	338.3	108,49
2009	363.4	116,5
2010	313,5	100,5
2011	321,0	102,9
2012	318.3	102,08
2013	315.9	101,3
2014	359.0	115,13
2015	340.5	109,2
2016	386.2	123,8
2017	345.5	110,8
2018	336.3	107,8
2019	323.7	103,8
2020	320.0	102,6
2021	290,4	93,13
2022	251,4	80,62
Note: Compiled on the basis of data from the statistical collection of the Republic of Kazakhstan

                      Table 1: COPD incidence rates in the Republic of Kazakhstan for 2002-2022 (per 100 thousand population).

In 2022, the national average incidence rate of COPD was 251.4 per 100,000 population. The highest incidence rate per 100,000 population by region was recorded in the Almaty region (502.8) and Almaty city (440.4). The lowest rates were recorded in the Mangystau (104.3) and West Kazakhstan (106.5) regions (Table 1). In the South Kazakhstan/Turkestan region, the incidence rate decreased from 665.0 per 100,000 population in 2013 to 254.3 per 100,000 population in 2022 (61.7%), Kyzylorda region — 55.5%, Zhambyl region — 0.6%. On the other hand, there was a significant increase in the incidence rate in the Almaty region from 375.9 per 100,000 population in 2013 to 502.8 per 100,000 population in 2012 (33.7%) (Figure 1).

Figure 1: Analysis of COPD incidence for 2013-2022 in the regions of Southern Kazakhstan (per 100 thousand population)

In 2022, the incidence rate in the Mangystau region decreased from 191.5 per 100,000 population to 104.3 per 100,000 population (45.5%), in the Atyrau region 4.7%, and in the Aktobe region 39.3%. A significant increase was noted in the West Kazakhstan region, from 55.3 per 100,000 population in 2013 to 106.5 per 100,000 population in 2022 (92.5%) (Figure 2). In 2022, the average incidence rate in Western Kazakhstan was 170.1 per 100,000 population, which is 47.7% lower than in Southern Kazakhstan and 16.8% lower than in Northern Kazakhstan.

Figure 2: Analysis of COPD incidence for 2013-2022 in the regions of Western Kazakhstan (per 100 thousand population)

The highest incidence rates were in the Mangystau region in 2018 — 379.1 per 100,000 population, exceeding the average for the West Kazakhstan region, where the rate that year was 127.3 per 100,000 population. The lowest rates were also in the Mangystau region in 2022, at 104.3 per 100,000 population. However, consistently high figures are observed in the Aktobe region, from 358.9 in 2013 to a peak of 344.6 in 2016 and a slight decrease to 218.4 in 2022. In the Mangystau region, the figures did not exceed 251.2 per 100,000 population.

Figure 3: Analysis of COPD incidence for 2013-2022 in the regions of Northern Kazakhstan (per 100 thousand population)

An increase in the incidence of COPD was observed in the regions of Northern Kazakhstan in 2013-2022. Compared to 2013, in 2022 the incidence rate in East Kazakhstan region increased by 0.18%, North Kazakhstan region — 26.3%, Pavlodar region — 78.4%, Kostanay region — 17.02%, Karaganda region — 92.7%, Akmola region — 42.9% (Figure 3). 

Discussion of Results

In 2018-2019-2020, there was an increase in cases in two regions, western and northern. Interestingly, the southern part of Kazakhstan experienced an earlier peak in cases, in 2016. A precise explanation is difficult to provide. We believe this is related to the geography and rate of spread of COVID-19, as the outbreak, which began in southern China, spread to western and northern regions. The inclusion criteria in Table 1 show the incidence rates of bronchitis (chronic and unspecified) and emphysema, registered for the first time, per 100,000 population. Thus, the COVID-19 virus was included under the heading "unspecified bronchitis," as well as newly diagnosed cases of chronic bronchitis. Factors such as lack of knowledge about COPD, late presentation to GPs (due to limited access to primary care or non-specific and/or mild symptoms in the early stages of the disease) and lack of population screening may play a role in underreporting COPD in some regions of the country. The main risk factors for COPD development are smoking, particulate matter pollution, occupational exposure to particulate matter, household air pollution from solid fuels, and exposure to secondhand smoke [4,5]. Additionally, the infectious factor in the pathogenesis of COPD should be noted [6,7]. According to our data, the peak of the COVID-19 epidemic has increased the incidence of COPD and newly diagnosed cases [8,9].

References

1. Mannino, D. M., & Buist, A. S. (2007). Global burden of COPD: risk factors, prevalence, and future trends. The Lancet, 370(9589), 765-773.
2. Nugmanova, D., Feshchenko, Y., Iashyna, L., Gyrina, O., Malynovska, K., Mammadbayov, E., ... & Vasylyev, A. (2018). The prevalence, burden and risk factors associated with chronic obstructive pulmonary disease in Commonwealth of Independent States (Ukraine, Kazakhstan and Azerbaijan): results of the CORE study. BMC pulmonary medicine, 18(1),26.
3. Rabe, K. F., Hurd, S., Anzueto, A., Barnes, P. J., Buist, S. A., Calverley, P., ... & Zielinski, J. (2007). Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease: GOLD executive summary. American journal of respiratory and critical care medicine, 176(6), 532-555.
4. Raherison, C., & Girodet, P. O. (2009). Epidemiology of COPD. Eur Respir Rev 18: 213-221.
5. Ruvuna, L., & Sood, A. (2020). Epidemiology of chronic obstructive pulmonary disease. Clinics in Chest Medicine, 41(3), 315-327.
6. Sandelowsky, Hanna, Ulla Møller Weinreich, Bernt B. Aarli, Josefin Sundh, Kristian Høines, Georgios Stratelis, Anders Løkke, Christer Janson, Christian Jensen, and Kjell Larsson. "COPD–do the right thing." BMC family practice 22, no. 1 (2021): 244.
7. Shchikota, A. M., Pogonchenkova, I. V., Turova, E. A., Rassulova, M. A., & Gumenyuk, S. A. (2020). Chronic obstructive pulmonary disease and COVID-19: topical issues. Pulmonologiya, 30(5), 599-608.
8. Sooronbaev, T. M., Uchkempirova, B. K., Shabykeeva, S. B.,Myrzaakhmatova, A. K., Kadyraliev, J. K., & Kirrakchimov,M. M. (2008). Prevalence of chronic obstructive pulmonary disease and its major risk factors among the inhabitants of high. PULMONOLOGIYA, (1), 51-56.
9. World Health Organization. Chronic obstructive pulmonary disease (COPD). 16 March 2023. https://www.who.int/ news-room/fact-sheets/detail/chronicobstructive-pulmonary-disease-(copd). (accessed 15.10.2023).