Cartogram of central nervous system cancer incidence in Kazakhstan

Introduction. The necessity of medical and geographical description is due to practical needs in the data of sanitary condition of various regions, population sickness rates and spreading of disease. Medical geographical maps are perspective method of interconnection establishment between factors of geographical environment and human health condition, occurrence and dynamics of various diseases. It is medical geographical approach of diagraming of separate forms of cancer that allows to disclosethe peculiarities of malignant tumors spreading in frame of naturalterritorial complexes, in close connection with existent systems of life and population activity conditions. Estimated new cases of central nervous system in 2018 is 296 851 for both sex in worldwide [1]. In the literature, many works have been published that reflect the specific incidence of malignant tumors of the central nervous system in various countries of the near and far abroad [2, 3, 4, 5, 6, 7].

In Kazakhstan, administrative territorial division of regions completely corresponds to medical geographical zones. Indicators of central nervous system (CNS) cancer incidence were defined in connection with administrative- territorial division of regions. In the investigation, we drew up a cartogram of CNS cancer incidence in Kazakhstan.

Materials and Methods. The source of information was the accounting and reporting materials according to the data of oncological institutions of the republic for 2007-2016 about new cases of AOR CNS. The data of the Statistics Committee of the Ministry of National Economy of the Republic of Kazakhstan of the total population of the republic were used [8]. As the basic method of CNS cancer study retrospective investigation with the use of descriptive and analytical methods of modern medical biological statistics was used. Crude incidence rates of 10 years (2007-2016) wereusedindrawingupofdiagram.Itwasappliedmethodofdiagramdrawingupproposedin1974byIgissinovS.I. based on indication of average quadrant decline (σ) from average (х) [9]. The scale of grades was calculated thus: σ was accepted as interval, we defined maximal and minimal degrees of incidence according to formula: x±1,5σ, thus minimal indicator is equal to x–1,5σ and maximal is equal to x+1,5σ. After that, we defined scale of diagramgrades: 1) (x–1,5σ)+σ; 2) (x– 1,5σ)+2σ; 3) (x–1,5σ)+3σ and others and grouping of indicators was calculated according to formula x±0,5σ, which corresponds to average level (x–0,5σи x+0,5σ), and values varied from average level of sickness rate is σ, shows decreased ((x–0,5σ)–σ) and increased ((x–0,5σ)–σ) indicators of sickness rate.

Results and discus. On the basis of abovementioned accounts, the diagram of CNS cancer incidence (figure 1) in various medical geographical zones of Republic was drawn up. In this connection the following groups of regions were defined:

Regions with low indicators (till 3.5⁰/0000) – Atyrau region (2.3), Western Kazakhstan region (3.0), Aktobe region (3.1), Northern Kazakhstan (3.4).In completely 4 regions.

Regions with average indicators (from 3.5 to 4.5⁰/0000) – Karagandy region (3.6), Astana city(3.6), Mangystau region (3.6), Southern Kazakhstan region (3.7), Akmola region (3.8), Kostanay region (3.8), Almaty region (4.0), Pavlodar region (4.3). Overall 8regions;

Regionswithhighindicators(above 4.5⁰/0000)–Eastern Kazakhstanregion(4.6), Zhambyl region (4.7), Almaty city (5.6) andKyzylordaregion (6.4). In total 4 region.

Conclusions. In the result of drawn up graphical map of CNS cancer incidence with territorial differentiation «locuses» with low and high indicators were underlined. Received results allows to organizers of health service to acquire distinctive picture relatively to central nervous system cancer incidence, level of sickness rate which gives the opportunity for acceptation of organized methodical activities according to earlier and prevention of CNS cancer and also organization of measures on decrease of risk factors influence power.

References

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