Year : 2022 | Volume
: 7 | Issue : 2 | Page : 76--82
Environmental risk factors for cardiovascular diseases using geographic information systems in an urban slum, Bengaluru
Deepa Srinivasan1, Avita Rose Johnson1, Subin Jang2, Savan Sara Mathew1, Farah Naaz Fathima1,
1 Department of Community Health, St. John's Medical College, Bengaluru, Karnataka, India
2 Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, USA
Dr. Deepa Srinivasan
Department of Community Health, St. John's Medical College, Sarjapur Road, John Nagar, Bengaluru - 560 034, Karnataka
Background: Cardiovascular disease (CVD), a growing epidemic, is influenced by various environmental factors, and the potential connection is not studied adequately.
Objective: Hence, our study was aimed at assessing the environmental risk factors for CVD and assessing perceptions about the same among the adults residing in an urban slum, Bengaluru.
Methods: A cross-sectional descriptive study was conducted using a validated environmental assessment tool – Environmental Profile of Community Health. It consists of two parts: (i) an assessment of the physical environment for CVD-risk behaviors and (ii) a questionnaire to collect residents' perceptions of their community's environmental risks for CVD.
Results: The community had two environmental risk factors for CVD-tobacco stores and fast-food restaurants. The community had ten convenience stores, all of which sold tobacco products. Vegetables and fruits were available, and the community also had a park for recreation. We interviewed a total of four study participants with a mean age of 38.5 ± 5.4 years. All participants reported that they have seen people smoke outside public places and inside residences. They felt that society disapproved of women and children smoking while men were excluded. Study participants have reported seeing tobacco and junk food advertisements. Tobacco was easily accessible and available to all ages.
Conclusions: The urban community was not CVD-friendly. Awareness regarding risk factors for CVD was good. Adequate urban planning, policy-level advocacy, and tailor-made lifestyle changes for patients are the key to preventing CVD.
|How to cite this article:|
Srinivasan D, Johnson AR, Jang S, Mathew SS, Fathima FN. Environmental risk factors for cardiovascular diseases using geographic information systems in an urban slum, Bengaluru.Int J Non-Commun Dis 2022;7:76-82
|How to cite this URL:|
Srinivasan D, Johnson AR, Jang S, Mathew SS, Fathima FN. Environmental risk factors for cardiovascular diseases using geographic information systems in an urban slum, Bengaluru. Int J Non-Commun Dis [serial online] 2022 [cited 2022 Sep 30 ];7:76-82
Available from: https://www.ijncd.org/text.asp?2022/7/2/76/351741
Cardiovascular disease (CVD), including coronary artery disease and cerebrovascular accidents, is the leading cause of morbidity and mortality worldwide. Low- and middle-income countries contribute to the major proportion of the burden of CVD. The prevalence of CVD and its risk factors is increasing in both urban and rural populations of India due to socioeconomic transitions that have resulted in major changes in socioeconomic status, dietary habits, physical activity, and lifestyle. In addition to the traditional risk factors for CVD, socio-environmental conditions also play an important role in the epidemiology of CVD.
Globally, environmental and public health specialists are concerned about the potential impact of environmental factors on CVD, such as built environment, availability and accessibility of tobacco products, recreation parks, and cultural practices in different communities, which may influence the lifestyle of people.,, The prevalence of risk factors may vary worldwide based on ethnicity and region, which means that prevention strategies cannot be formulated commonly.
Environmental risk factors can be assessed using tools such as Environmental Profile of Community Health (EPOCH), Neighborhood Environment Assessment Tool, Walkability Index, and systematic pedestrian and cycling environmental scan. Environmental factors have a significant role in the development of CVD yet have been poorly documented in the medical literature. The built physical and social environment influences lifestyle-related risk factors for CVD. Hence, profiling the neighborhood environment in terms of CVD risks moves beyond strategies for prevention and control at the individual level and instead helps in formulating community-level interventions. Poor and underprivileged communities have limited access to quality health care and would therefore greatly benefit from preventive strategies for CVD.
There are studies that have studied on specific CVD risk factors from an environmental perspective; however, there are no studies that have studied all the risk factors in the same community. Furthermore, the already existing data are not representative of low- and- middle-income countries, although the burden of CVD is much higher in these countries.,,,,,, Hence, this study was conducted with the specific aims of assessing the environmental risk factors that unfavorably contribute to CVD risk-related behaviors in an urban underprivileged area of Bengaluru, India, and to assess the knowledge and attitude of residents in the community about environmental risk factors for CVD.
Study design and setting
A descriptive study was conducted in an urban slum of Bengaluru, which is the field practice area of the medical college where the researchers are based.
The EPOCH instrument comprises two parts: (i) assessment of the physical environment, which enables CVD-risk behaviors and (ii) an interviewer-administered questionnaire to collect residents' perceptions of their community's environmental risks for CVD.
EPOCH-1 is a “Direct Observations of the Community Environment” and it is a physical audit tool. The first part has two sections. In the first section, the community environment is assessed on community demographics where the essential infrastructure and services in the community are recorded. In the next section, the observer will do a community observation walk of approximately 1 km from a predefined point and will assess the community. In addition, the observer will also assess a randomly chosen tobacco retail outlet, grocery store, restaurant, and a pharmacy shop. The first part assessed essential infrastructure and services in the community which influences CVD-risk behavior such as the availability of parks and walking areas, unhealthy foods, tobacco, fruits and vegetables, and advertisements for the same.
The second part included questions to capture individual observations and awareness of local laws and regulations and opinions about CVD-risk behaviors, for example, whether smoking is allowed, and their opinion of the social acceptability of smoking. EPOCH-2 also assessed the knowledge and attitudes regarding environmental risk factors for CVD from an individual perspective.
Purposive sampling – Community members who have been residing in the same community for more than a year.
The study population for the second part of EPOCH was chosen through purposive sampling. We included adults above 18 years of age who are residents of the community. We excluded those residents who have been residing in the locality for less than a year.
Approval was obtained from the Institutional Ethics Committee, and written informed consent was obtained from all participants before administering the questionnaire.
The data were entered into Microsoft Excel and was analyzed using IBM SPSS Statistics for Windows, version 11 (IBM Corp., Armonk, N.Y., USA). All study variables were described using descriptive statistical methods such as frequencies, percentages, mean, and standard deviation.
A community assessment was done in an urban slum, Bengaluru. It is a centered community. The Global Positioning System location of this community was 12.57839 north and 77.36053 east. The roads were completely paved, had sidewalks on either side, but were poorly maintained. The community had adequate electrical street lighting and traffic lights.
The community was connected to other areas by buses and had a public recreational park, primary and secondary school, university, post office, bank, government building, police station, public hospital, and private clinics within 20 km of the community center.
During the community walk, we found advertisements on tobacco and signages that prohibit smoking. There were no advertisements on junk food, soft drinks, and advertisements promoting health. The community had ten convenience stores, all of which sold tobacco products. There was one supermarket, one dairy store, three shops selling vegetables and fruits, and one butcher shop. There were two street junk food stalls and two fast-food restaurants. The community had five bakeries within the 1 km that was observed during the community walk.
The tobacco outlet which was assessed was situated at 12.57829 north and 77.36852 east. The store had a point-of-sale tobacco advertising, and tobacco products were openly displayed. The store had seven varieties of cigarettes, four types of bidi, and five types of chewable tobacco products. Cigarettes were sold as packs with 2–10 cigarettes per pack. The packs complied with Cigarettes and other Tobacco Products Act (COTPA) regulations and had pictorial health warnings. The cheapest variety costed ₹3 for a pack of ten cigarettes. Smoking cessation aids were not available in the store.
The grocery store assessed was located at 12.57834 north and 77.36852 east. It stocked a variety of fruits and vegetables which were visible from the outside. More than three kinds of fruits and vegetables were damaged. The store did not sell specially packaged fruits, but specially packaged vegetables were available. Milk, white bread, white rice, chicken drumsticks, pork, egg, etc., were sold at the store. The store advertised junk food, but there were no advertisements on sweet drinks, fruits and vegetables, cigarette/tobacco products, or alcohol. Packets of fried potato chips and biscuits examined randomly were locally manufactured and did not have food labels.
The fast-food joint that was assessed was located at 12.57849 north and 77.36852 east. The store did not have healthy menu options or buffets. The store had a promotional offer wherein the customer could opt for bigger potions at a relatively small price. Smoking was not allowed, and tobacco products were not sold at the premises.
The pharmacy that was assessed was located at assessed at 12.57839 north and 77.36852 east. It stocked medicines for common health problems including antihypertensives, cholesterol-lowering drugs, oral diabetic drugs and insulin, antibiotics, and paracetamol. The pharmacy did not sell tobacco cessation products.
We interviewed a total of four study participants with a mean age of 38.5 ± 5.4 years. Majority of them were female (75%), with mean years of education of 7.5 ± 1.2 years. Majority were currently employed, and all of them had to travel outside their community for work with a mean distance of 7.5 km. Most of them, 3 (75%), used motorcycles for traveling, and the mean time taken to reach was 26 min. The mean hours spent at the workplace was 7 h. Most of them used motorcycles to go to the grocery store, and the meantime taken was 16.2 ± 5.4 min. All participants had access to a paid Internet connection.
None of the participants were smokers, and hence, they have not received any advice from a doctor or health professional to quit smoking. Most of the participants reported none of their friends smoke or consume alcohol. One was overweight.
Community tobacco environment
All participants reported that they had seen people smoke outside offices, hospitals, libraries, schools, government buildings, and trains/buses stations. None of the participants reported seeing people smoke inside premises of public buildings. Most participants reported that people smoked in designated smoking areas inside restaurants and pubs. Smoking was commonly observed by people inside and outside their residences. Majority felt that people should not smoke at any place.
Study participants have reported seeing tobacco advertisements in permanent signages along the roads and on buildings. However, none of them reported seeing any advertisements for tobacco products in both traditional media such as TV, radio, newspapers, Internet, and nontraditional forms such as sponsorships, free samples, and promotional vouchers. All of them reported seeing smoking cessation advertisements in both traditional and nontraditional forms of advertisements.
The social acceptability of tobacco products was assessed. All the participants reported that society disapproves of smoking among children, teenagers, and women. Only some felt that society disapproves of smoking among males. All participants reported that tobacco products were easily accessible and were available to all, including youth.
Awareness regarding smoking laws was assessed. All participants were aware of laws governing smoking in public places, advertising of tobacco products, mandatory health warnings on cigarette packets, and prohibition of the sale of cigarettes to children <18 years.
All the participants were aware of the ill effects of tobacco use, such as chronic obstructive lung disease, lung cancer and throat cancer, ischemic heart disease, diabetes mellitus, and stroke.
Community nutrition/physical activity environment
All participants reported seeing junk food and soft drink advertisements in traditional media and none in nontraditional forms in the last 6 months. Some participants reported seeing advertisements on alcohol ion TV and in newspapers alone and not in any other forms. Participants reported seeing advertisements on good diet and physical activity only in TV.
More than three-fourth of the participants reported that it is culturally acceptable to eat healthy foods and drinks and the traditional local diet. All participants felt there is no societal pressure on adults to either consume or not consume junk food; however, children feel peer pressure to consume junk food and parental pressure not to consume junk food.
All participants were aware that weight reduction, exercise, increased consumption of vegetables, reduced fat and salt in the diet, and avoidance of smoking will prevent CVDs.
Almost all participants reported seeing nutrient labeling on locally made and imported food items. None of the participants were aware of the laws that encourage healthy eating to do adequate physical activity and laws that discourage advertising junk food to children.
Community social environment
Majority of the study participants reported that it is common for people to advise all children and teenagers, including those not from their families to stop smoking, eat healthy food, and exercise.
To consolidate the community's environmental profile, we considered seven major environmental risk factors for CVD which include (1) presence of a tobacco store, (2) presence of restaurant/fast-food outlets, (3) absence of fruit/vegetable stores, (4) absence of pharmacy (5) absence of sidewalks, (6) absence of public parks/recreation parks, and (7) absence of traffic lights. The communixsty we observed had two of the most important environmental risk factors for CVD, i.e., the presence of tobacco stores and fast-food restaurants.
The environment in which we live influences our health and the risk of acquiring CVD even in the absence of genetic changes.
The community that we assessed had a high vehicle density making it unsuitable for pedestrians to walk. However, the community had a designated park for physical activity. Physical inactivity is one of the major modifiable risk factors for CVD. The presence of public places and parks for physical activity and recreation is a determinant for physical activity.,,,, With increasing motorized transport, physical activity mainly relies on leisure-time physical activity. The municipal corporation of Bengaluru has officially allocated designated places for parks with open-air gym facilities in all its wards. The availability of such facilities will increase physically active people, as studied by Ariane L et al. on “The Significance of Parks to Physical Activity and Public Health.” Structural changes in the environment and urban planning influence physical activity both at the individual and community level.
Community tobacco environment
The community that we assessed had a variety of tobacco products easily available to all, with the point of sale tobacco advertising and tobacco products openly displayed. This puts a wide variety of tobacco products well within reach for the residents at an affordable cost which will influence smoking behaviors in the community. Tobacco products in the stores complied with the COTPA legislations of packaging and labeling; however, they did not comply in terms of marketing. We found that tobacco was available within 100 yards of educational institutions, which is in clear violation of the existing tobacco control legislation of India (COTPA). Although tobacco control in India is governed by stringent laws with respect to tobacco use, there is cause for concern in their implementation. Smoking in public places is banned, and people continue to smoke in public places. This behavior not only increases the exposure to smoke particulate matter, causing various medical problems, it is also associated with an increase in the number of individuals taking up smoking due to peer pressure. This points toward the need for strict implementation of the existing legislation. A study done in four countries, i.e., Canada, the USA, the United Kingdom, and Australia, showed that smoke-free public places help adopt smoke-free homes, which increased the frequency of smoking cessation attempts. This strategy can be used to increase smoking cessation among smokers and reduce the prevalence of smoking in particular.
A study done by Henriksen et al. in California among adolescents found that the prevalence of smoking was 3.2 times higher in neighborhoods with tobacco outlets than the neighborhoods without them. This puts adolescents in the community at high risk to start using tobacco. This is evidenced by the results of Global Adult Tobacco Survey, which show a high prevalence of tobacco use in India (28.6%) and in Karnataka (22.8%), where tobacco products are easily accessible in all settings. Strategies for tobacco control should therefore be focused at a broader level in synergy with the individual level. This can be done by more coordinated efforts to help people in tobacco cessation and targeting the youth population to avoid them taking up a habit and monitoring strict compliance with the existing legislation.
Community nutrition environment
The assessment of the community nutrition environment revealed that the community had almost all varieties of fruits and vegetables and also restaurants and bakeries. Numerous studies have identified the importance of the physical environment in relation to healthy dietary habits. The availability of fruits and vegetables at an affordable cost seems to increase their intake. The pattern of healthy dietary habits is also influenced positively by the accessibility of fruit and vegetable stores in the community.
In our study, all the participants had seen advertisements for junk food and soft drinks on various media. Mass media plays an important role, and people are exposed to various messages – both healthy and unhealthy. They compete frequently with various pull marketing techniques, social and peer pressure, and behaviors driven by addiction or habit. In addition to these factors, other factors such as easy availability and affordability of unhealthy foods and nonavailability of healthy foods also play a major role in shaping the dietary patterns of the residents in the community. Thus, the community nutrition environment influences an individual's dietary choices. Efforts should be taken to encourage people to do small kitchen gardening, and awareness should be created regarding the importance of healthy dietary choices.
Community social environment
Social support plays a major role in the prevention and management of CVD. A study done on social support and its relation to CVD showed that lack of support is associated with an increased prevalence of morbidity and mortality associated with CVD. The study proved that social support reduces psychological stress, and thereby, the incidence of hypertension and CVD is reduced. Peer pressure also plays a major role in the adoption of healthy lifestyles such as healthy diet, physical activity, and the avoidance of tobacco.
Conclusions and Recommendations
The community environment plays a very crucial role in the adoption of a healthy lifestyle among individuals. The urban underprivileged community was not CVD-friendly due to the easy availability and accessibility of tobacco, restaurants selling unhealthy foods, and lack of safe places for physical activity, etc., This will definitely affect individuals in taking up healthy choices, putting them at greater risk for developing CVD. Measures have been taken in a few places by the establishment of parks and designated public places for physical activity. Additional measures should include adequate urban planning for the construction of roads that are completely paved, well-maintained, and pedestrian-friendly. Tobacco control legislation, although already present, should be backed up with strict monitoring to ensure uniform implementation.
There is a strong need to increase awareness regarding the ill effects of smoking, the importance of physical activity, and the consumption of healthy foods. The availability of smoking cessation aids and healthy food options in restaurants should also be made available at an affordable cost in all the communities.
This study will emphasize the importance of assessing the environment in which patients live from a clinician's perspective. Clinicians also need to take into consideration the environmental factors which will influence the individual-level risk factors greatly, and solutions to adopt a healthy lifestyle should be tailor-made for each patient. In the bigger picture, public health practitioners and physicians should also advocate to the government for a healthy environment that is CVD-friendly to bring a change at the policy level. This will give a holistic treatment approach in managing CVD, and this will definitely take a step forward in reducing the burden of CVD globally.
We are pleased to thank each one who has helped us to conduct this study. I would like to thank the management authorities, faculty, postgraduates, and the office staff of the Department of Community Health, St. John's Medical College, Bengaluru, India.
Ethical approval statement
Approval was obtained from the Institutional Ethics Committee and written informed consent was taken from all participants before administering the questionnaire.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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