Leading Article
4 Gafarov V.V. et al.
Sleep disturbances and physical activity as risk factors for cardiovascular diseases... doi: 10.24412/2311-1623-2022-36-4-9
Sleep disturbances and physical activity
as risk factors for cardiovascular diseases in an open population of Novosibirsk aged 45-64 years (WHO MONICA-MOPSY program)
Gafarov V.V.12, Gromova E.A.12, Panov D.O.12, Gagulin I.V.12, Tripelgorn A.N.1,2, Gafarova A.V.1,2
1 National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Novosibirsk, Russia.
2 Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences, Novosibirsk, Russia.
Authors
Valeriy V. Gafarov*, M.D., doctor of medicine, professor, honored science worker of the Russian Federation, head of the laboratory of Psychological and Sociological Problems of Internal Diseases of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences Novosibirsk, Russia.
Elena A. Gromova, M.D., leading researcher of the laboratory of Psychological and Sociological Problems of Internal Diseases of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences Novosibirsk, Russia.
Dmitriy O. Panov, M.D., Ph.D., senior researcher of the laboratory of Psychological and Sociological Problems of Internal Diseases of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences Novosibirsk, Russia.
Igor V. Gagulin, M.D., senior researcher of the laboratory of Psychological and Sociological Problems of Internal Diseases of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences Novosibirsk, Russia.
* Corresponding author. Tel. +7 (913) 892-0003. E-mail: valery.gafarov@gmail.com
^ International Heart and Vascular Disease Journal. Volume 10, № 36, December 2022
ISSN: 231 1-1623 (Print) 5
l^Bf) ISSN: 231 1-1631 (OnLine) e * http://www.heart-vdj.com
Alexandra N. Tripelgorn, M.D., junior researcher of the laboratory of Psychological and Sociological Problems of Internal Diseases of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences Novosibirsk, Russia.
Almira V. Gafarova, M.D., Ph.D., senior researcher of the laboratory of Psychological and Sociological Problems of Internal Diseases of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, Interdepartmental Laboratory of Cardiovascular Diseases Epidemiology of the Russian Academy of Sciences Novosibirsk, Russia.
Abstract
Objective. This study aimed to assess the association between sleep disturbances and physical activity as the risk factors for cardiovascular diseases in an open population aged 45-64 years of Novosibirsk.
Materials and methods. The IVth screening of random representative sample of the population aged 45-64 years was carried out between 2003-2005 years and included 1650 participants (men (n = 576), mean age 54.23 ± 0.2 years, response rate 61 %; women (n = 1074), mean age — 54.27 ± 0.2 years, response — 72 %). Physical activity was assessed using the scale "Knowledge and attitude towards one's own health" of WHO "MONICA-Psychosocial" program. The Jenkins Sleep Evaluation Questionnaire wa s used to study sleep disorders.
Results. In an open population aged 45-64 years, 74.2 % of participants experienced sleep disturbances; 65.8 % of men (satisfactory sleep — 53.6 %, poor sleep — 12.2 %) and 78.6 % of women (satisfactory sleep — 58.9 % and poor sleep — 19.7 %) (x2 = 38.553 df = 2; p < 0.001). Among men who described their sleep as "poor", 35.7 % believed that they "should exercises, but they don't" and 28.6 % "tried, but unsuccessfully" (x2 = 27.850 df = 8; p < 0.001). Among women who believed that their sleep was "poor", 47.2 % answered "I should exercise, but I don't" (x2 = 26.453 df = 8; p < 0.001). Men who spend their leisure time "physically passive" more often characterized their sleep as "poor" (24.3 %) than "good" (21.8 %) (x2 = 92.019 df = 6; p < 0,0001). To the question: "Has your physical activity changed over the past 12 months?" 30.4 % of men and 35.3 % of women of working age answered that they be-
came "less mobile", among them 40 % of men (x2 = 22.929 df = 4; p < 0.0001) and 34.9 % of women (x2 = 58.992 df = 4; p < 0.0001), believed that they had "poor" sleep. Among participants who answered to the question "How do you rate your physical activity compared to other people your age?" that they were "somewhat more passive", 7.1 % of men (x2 = 28.520 df = 8; p < 0.0001), and 11.3 % of women (x2 = 90.554 df = 8; p < 0.0001) had "poor" sleep. Conclusion. The association between sleep disturbances and physical activity among men and women aged 45-64 years of Novosibirsk population was established. Considering close relationship between sleep disturbances and low physical activity, further prospects open up to investigate the combined effect of the above factors on cardiovascular health.
Keywords: sleep disturbance, physical activity, population, risk, cardiovascular disease.
Conflict of interest: none declared. Received: 19.09.2022 Accepted: 16.11.2022
For citation: Gafarov V.V., Gromova E.A., Panov D.O., Gagulin I.V., Tripelgorn A.N., Gafarova A.V. Sleep disturbances and physical activity as risk factors for cardiovascular diseases in an open population of Novosibirsk aged 45-64 years (WHO MONICA-MOPSY program). International Heart and Vascular Disease Journal. 2022; 10(36): 4-10. doi: 10.24412/2311-1623-2022-36-4-9
Introduction
Sleep disturbances, including chronic insomnia, are major public health issues [1]. The prevalence of sleep disorders ranges from 25 % to 48 % worldwide that indicates that these disorders are relatively common [2]. Sleep disturbances are mainly associated with chronic fatigue, impaired sustained attention and working memory, as well as reduced quality of life [3]. It is also noteworthy that numerous studies
have demonstrated the association between sleep impairment and cardiovascular diseases as the leading causes of death [4].
Physical activity is one of the major factors for health maintenance [5]. Regular physical activity reduces the prevalence of cardiovascular [6], metabolic [7] and neurodegenerative disorders [8], and decreases all-cause mortality [5].
Leading Article
6 Gafarov V.V. et al.
Sleep disturbances and physical activity as risk factors for cardiovascular diseases... doi: 10.24412/231 1-1623-2022-36-4-9
Both insufficient sleep and low physical activity are associated with poor health outcomes, and those who are more physically active tend to have better sleep [9]. Therefore, physical activity may improve sleep quality, and vice versa sleep may lead to greater physical activity, however the direction of these relationship has not been clearly established yet [10].
Nevertheless, there is little evidence to establish optimal type or minimum level of daily physical activity that can positively affect sleep quality and provide clear guidance for public health or clinical interventions for insomnia. Given research data to date, the activity level that was recommended by the World Health Organization (WHO) in 2010 and have been included into the guidelines for promoting cardiovascular health worldwide seems to be the best candidate: 150 minutes of moderate-intensity physical activity per week that is usually mistaken for walking [11].
Therefore, this study aimed to assess the relationship between sleep disturbances and physical activity as cardiovascular risk factors in an open population aged 45-64 years in Novosibirsk.
The study has been approved by the Ethics Committee of the National Research Center for Therapy and Preventive Medicine — a branch of the Institute of Cytology and Genetics of the Russian Academy of Sciences, protocol № 1 from 14th of March, 2002, and protocol № 12 from 8th of December, 2020.
Materials and methods
The IVth population screening have been performed between 2003-2005 years and included 1650 people from Oktyabrsky district of Novosibirsk who formed random representative sample aged 45-64 years (men n = 576, mean age — 54.23 ± 0.2 years, response — 61 %; women — n = 1074, mean age — 54.27 ± 0.2 years, response — 72 %) [12]. response — 72 %). Daily physical activity was assessed using the scale "Knowledge and attitude towards one's own health". The Jenkins Sleep Evaluation Questionnaire was used to study sleep disorders and sleep duration. The scale has been validated in the course of large-scale epidemiological study carried out in the framework of the WHO MONICA program (Multinational Monitoring of Trends and Determinants of Cardiovascular Disease) and the MONICA-Psychosocial Optional Study (MOPSY) subprogram between 1988-1994 [13]. The questionnaires were filled out by the participants themselves.
Statistical analysis has been performed using the SPSS 19 software [12]. The Pearson's chi-square X2 test has been used to assess the significance of differences between groups. The significance level was set as p < 0.05.
Results
In the open population aged 45-64 years, 74.2 % of participants experienced sleep disturbances: 65.8 % of men (satisfactory sleep — 53.6 %, poor sleep — 12.2 %) and 78.6 % of women (satisfactory sleep — 58.9 % and poor sleep — 19.7 %) (x2 = 38.553; df = 2 p < 0.001) (Table 1).
Table 1. Self-reported sleep quality in an open population aged 45-64 years old
Sleep quality men women total
n % n % n %
Good sleep 197 34,2 229 21,3 426 25,8
Satisfactory sleep 309 53,6 633 58,9 942 57,1
Poor sleep 70 12,2 212 19,7 282 17,1
Total 576 100 1074 100 1650 100
Note. x2 = 38,553 df = 2; p < 0,001
Among study participants aged 45-64 years, only 14 % of men and 10.3 % of women regularly exercised, and "good" sleep prevailed both among men (17.3 %) and women (15, 7 %) from this group. The most popular answer among both women (34.4 %) and men (40.8 %) was: "I should exercise, but I don't". Men who assessed their sleep as "poor" more often believed that they "should exercise, but they don't" — 35.7 %, and 28.6 % "tried, but unsuccessfully" (x2 = 27.850 df = 8; p < 0.001). Among women who characterized that their sleep as "poor", the answer "I should exercise, but I don't" was more common: 47.2 % (x2 = 26.453 df = 8; p < 0.001) (Table 2).
All responders were asked the question: "How do you spend your leisure time?". The majority of men (45.1 %) and women (37.1 %) answered "anything happens" and, in this category, 47.1 % of men (%2 = 29.683 df = 6; p < 0.0001) and 44.3 % of women (x2 = 92.019 df = 6; p < 0.0001) rated their sleep as "poor". 20.5 % of men and 17.4 % of women did not perform any physical activity during their leisure time (lying, sitting, watching TV, reading, writing, making something by hand, etc.). Men who spent their leisure time without physical activity more often had poor sleep (24.3 %) than good sleep (21.8 %) (Table 3).
To the question: "Has your physical activity changed over the past 12 months?" among people of working
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Table 2. Sleep disturbances and physical activity in an open population aged 45-64 years of Novosibirsk
Do you exercise (excluding daily Good sleep Satisfactory sleep Poor sleep Total
professional activity)? n % n % n % n %
I don't need it 56 28,4 17,5 11 15,7 121 21,0
I should exercise, but I don't 66 33,5 107 34,6 25 35,7 198 34,4
* I tried, but unsuccesfully 41 20,8 108 35,0 20 28,6 169 29,3
<D I exersice regularly 34 17,3 37 12,0 11 15,7 82 14,2
Physical exercises are contraindicated for me 0 0 3 1,0 3 4,3 6 1,0
Total 197 100 309 100 70 100 576 100
I don't need it 23 10,0 51 8,1 26 12,3 100 9,3
I should exercise, but I don't 93 40,6 245 38,7 100 47,2 438 40,8
* c I tried, but unsuccesfully 71 31,0 271 42,8 62 29,2 404 37,6
<D E I exersice regularly 36 15,7 56 8,8 19 9,0 111 10,3
s Physical exercises are contraindicated for me 6 2,6 10 1,6 5 2,4 21 2,0
Total 229 100 633 100 212 100 1074 100
Note. *x2 = 27,850 df = 8; p < 0,001, ** x2 = 26,453 df = 8; p < 0,001
Table 3. Sleep disturbances and leisure time in an open population aged 45-64 years of Novosibirsk
How do you spend your leisure time? Good sleep Satisfactory sleep Poor sleep Total
n % n % n % n %
Physically active (working in the garden, playing sports, walking, cycling, running, etc.) 50 25,4 61 19,7 19 27,1 130 22,6
* Anything happens 94 47,7 133 43,0 33 47,1 260 45,1
£Z a Physically passive (lying, sitting, watching TV, reading, writing, making something by hand, etc.). 43 21,8 58 18,8 17 24,3 118 20,5
I don't have leisure time 10 5,1 57 18,4 1 1,4 68 11,8
Total 197 100 309 100 70 100 576 100
Physically active (working in the garden, playing sports, walking, cycling, running, etc.) 75 32,8 165 26,1 70 33,0 310 28,9
* * Anything happens 92 40,2 212 33,5 94 44,3 398 37,1
a E o 5 Physically passive (lying, sitting, watching TV, reading, writing, making something by hand, etc.). 55 24,0 94 14,8 38 17,9 187 17,4
I don't have leisure time 7 3,1 162 25,6 10 4,7 179 16,7
Total 229 100 633 100 212 100 1074 100
Note. * x2 = 29,683 df = 6; p < 0,0001, ** x2 = 92,019 df = 6; p < 0,0001
Table 4. Sleep disturbances and physical activity in an open population aged 45-64 years of Novosibirsk
Has your physical activity changed (total mobility, Good sleep Satisfactory sleep Poor sleep Total
sports, etc.) over the last 12 months? % n % n % n % n
Yes, I have become more active 20 10,2 25 8,1 5 7,1 50 8,7
* £Z It hasn't change 142 72,1 172 55,7 37 52,9 351 60,9
I've become less active 35 17,8 112 36,2 28 40,0 175 30,4
Total 197 100,0 309 100,0 70 100,0 576 100,0
* Yes, I have become more active 38 16,6 34 LO 7 3,3 79 7,4
£Z a It hasn't changed 5 63,3 340 53,7 131 61,8 616 57,4
E o I've become less active 46 20,1 259 40,9 74 34,9 379 35,3
5 Total 229 100,0 633 100,0 212 100,0 1074 100,0
Note. * x2 = 22,929 df = 4; p < 0,0001, ** x2 = 58,992 df = 4; p < 0,0001
age, 30.4 % of men and 35.3 % of women answered that they have become "less mobile". Among those who answered that they have become "less mobile", 40 % of men (x2 = 22.929 df = 4; p < 0.0001) and 34.9 % of women (x2 = 58.992 df = 4; p < 0.0001), believed that their sleep was "poor". Only 8.7 % of men and 7.4 % of women answered that they became "more physical-
ly active", among them 10.2 % of men and 16.6 % of women had "good" sleep (Table 4).
To the question: "How do you rate your physical activity compared to other people your age?" the majority of respondents answered "the same as others" — 60.2 % of men and 53.7 % of women. Among those who believed that they were "significantly more
Leading Article
8 Gafarov V.V. et al.
Sleep disturbances and physical activity as risk factors for cardiovascular diseases...
doi: 10.24412/231 1-1623-2022-36-4-9_
Table 5. Sleep disturbances and physical activity in an open population aged 45-64 years of Novosibirsk
How do you rate your physical activity compared to other people your age? Good sleep Satisfactory sleep Poor sleep Total
n % n % n % n %
Men* Significantly more active 31 15,7 32 10,4 2 2,9 65 11,3
Somewhat more active 49 24,9 59 19,1 18 25,7 126 21,9
Same as others 108 54,8 199 64,4 40 57,1 347 60,2
Somewhat more passive 9 4,6 14 4,5 5 7,1 28 4,9
Significantly more passive 0 0 5 1,6 5 7,1 10 1,7
Total 197 100 309 100 70 100 576 100
Women** Significantly more active 56 24,5 44 7,0 24 11,3 124 11,5
Somewhat more active 74 32,3 137 21,6 47 22,2 258 24,0
Same as others 83 36,2 391 61,8 103 48,6 577 53,7
Somewhat more passive 13 LO 43 6,8 24 11,3 80 7,4
Significantly more passive 3 1,3 18 2,8 14 6,6 35 3,3
Total 229 100 633 100 212 100 1074 100
Note. * x2 = 28,520 df = 8; p < 0,0001, ** x2 = 90,554 df = 8; p < 0,0001
active" than others, 15.7 % of men and 24.5 % of women had good sleep. On the contrary, among men and women who answered that they were "somewhat more passive" than others, "bad" sleep prevailed both among men - 7.1 % and women - 11.3 % (men X2 = 28.520 df = 8; p < 0.0001 and women x2 = 90.554 df = 8; p < 0.0001) (Table 5).
Discussion
One of the promising and modern issues for epide-miological and experimental research is: does regular physical activity improve the quality of sleep? The expectation that exercise will improve sleep can be explained by traditional hypotheses that sleep is considered as energy conservation strategy and is essential for body repair or thermoregulatory functions that underpins much of the research in this area. Regular exercise can be beneficial for overall well-being, but can also cause stress [15].
Considering mentioned above background, we analyzed self-reported sleep quality and physical activity among working population aged 45-64 years old. According to our data, 1/3 of population experienced sleep disturbances. Sleep and physical activity affect each other through complex reciprocal relationship that involve various physiological and psychological mechanisms. Physical activity is usually considered beneficial for sleep; however, this association depends on several factors such as gender, age, fitness level, sleep quality and exercise characteristics (intensity, duration, time of the day, environment) [16]. In our study all the participants answered the question "Do you exercise (excluding daily professional activity)?" It turned out that only 14 % of men and 10.3 % of women regularly exercised, and they more often had
"good" sleep. Men who answered "I should exercise, but I don't" or " I tried, but unsuccessfully" were more likely to rate their sleep quality as "poor". Women who rated sleep as "poor" more often believed that "they should exercise, but they don't."
WHO in 2010 followed by international healthcare systems recommended to achieve at least minimum level of 150 minutes of moderate-intensity physical activity per 5 days a week [11]. It is also significant not only to do physical exercises, but also to spend leisure time actively in order to achieve result. To the question: "How do you spend your leisure time?" — 2/3 of men and 1/3 of women answered that "anything happens", and in this category of participants "poor" sleep prevailed. Similarly, among men who spend their leisure time physically passively, "poor" sleep was the most common answer.
It is noteworthy that the change in physical activity affected the quality of sleep just in one year. About 1/3 of the men and women responded that they have become "less active" and the quality of sleep in this category decreased. On the other hand, men and women who answered that they have become "more active" also improved their sleep. In addition, men and women who felt that they have become "significantly more active" than others were more likely to rate their sleep as "good". Among those who believed that they were "somewhat less active" than people around them "poor" sleep prevailed. Thus, this study confirms that the increase of the level of physical activity improves the quality of sleep and, conversely, the decrease of physical activity leads to sleep impairment [11].
To sum up our findings, exercise can positively affect sleep. The clinical significance of this study is that exercise may represent an alternative or ad-
International Heart and Vascular Disease Journal. Volume 10, № 36, December 2022 ISSN: 231 1-1623 (Print) ISSN: 2311-1631 (OnLine) http://www.heart-vdj.com
ditional tool to existing treatment for sleep disturbances. Moreover, physical activity can be used as preventive strategy in clinical practice to manage the first symptoms insomnia before the onset of severe chronic insomnia [17].
Conclusion
The association between sleep disturbances and physical activity in the population of Novosibirsk aged 45-64 years was established.
For the first time in the population of Novosibirsk, it has been shown that men who assessed their sleep
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