Cognitive functions and professional status in the open population of Russia/Siberia among adults aged 25–44 years

Objective: to establish associations of cognitive functions (CFs) and professional level in an open population of Novosibirsk aged 25–44 years.

Patients and methods. The subject of the study was a random representative sample of one of the Novosibirsk districts population aged 25–44 years (463 men, mean age 35.94±5.957 years, and 546 women, mean age 36.17±5.997 years) in 2013–2016. CFs were screened using: A.R. Luria 10 words learning task – immediate and delayed recall after the interfering task; Bourdon Test (BT); exclusion of “the fifth extra” test; verbal fluency test (naming animals in 1 min). Education level and professional status were assessed according to the criteria of the WHO international program MONICA protocol.

Results and discussion. The analysis showed that the management and engineering and technical staff (ETS) coped significantly better with cognitive tests than manual labor workers. The analysis of memory using the A.R. Luria test showed that the differences in the first recall of 10 words between manual labor workers and managers reached 0.849 words, in the mean number of correctly remembered words it reached 0.735 words, and in delayed recall – 1.096 words (p<0.05). Attention assessment using BT revealed that the number of letters crossed out in 1 min was higher among the management staff compared to the manual labor workers, reaching 4.978 characters (p<0.05). ETS scores in this test were close to the management staff scores (p<0,0001). Also, a tendency to a smaller number of mistakes made by managers and ETS compared to workers was revealed in the BT. In the analysis of semantic associations in the verbal fluency test the differences in the number of animals named per 1 min reached 3.007 animals between manual labor workers and managers. Similar differences were observed between manual labor workers and ETS (p<0.05). Abstract reasoning evaluation using the “the fifth extra” test showed that managers and ETS excluded a greater number of words that did not correspond to the logical series (i.e., they showed the best result in this test) than manual labor workers (p<0.05). ETS and management staff showed best performance in cognitive tests compared to manual labor workers of the same educational level.

Conclusion. A quantitative association has been established between a low professional level, level of education and a decrease in cognitive functions among people aged 25–44 years.

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