|Year : 2013 | Volume
| Issue : 3 | Page : 101-107
Job stress and hypertension in younger software professionals in India
Giridhara R Babu1, Tanmay Mahapatra2, Roger Detels2
1 Department of Epidemiology, Public Health Foundation of India, IIPH H, Bangalore Campus, SIHFW Premises, Bengaluru, Karnataka, India; Department of Epidemiology, University of California, Los Angeles, California, USA
2 Department of Epidemiology, University of California, Los Angeles, California, USA
|Date of Web Publication||17-Apr-2014|
Giridhara R Babu
Public Health Foundation of India, IIPH-H, Bangalore Campus, SIHFW Premises, Beside Leprosy Hospital, 1st Cross, Magadi Road, Bengaluru - 560 023, Karnataka, India
Source of Support: The study was supported through NIH/Fogarty
International center, Fogarty/UCLA AIDS International Research
and Training Program.(Grant Number: D43 TW000013) and the
Public Health Foundation of India provided partial grant, Conflict of Interest: None
Background: We report the results of a moderately large study (1071) to study the prevalence of hypertension among software professionals in the Indian subcontinent employed at 27 different companies in Bangalore. The focus of our study is on the age gradient of hypertension prevalence and exploring the association of workplace psychosocial predictors of hypertension. Materials and Methods: We used mixed methods sampling strategy, the first stage of which involved stratified sampling to select the clusters of software companies in Bangalore and the second stage involved selecting individual companies through purposive sampling. Job stress questionnaire was self-administered to collect information on job stress and blood pressure classification is done based on 7 th report of Joint National Commission. Results: The prevalence of hypertension among Information Technology/Information Technology Enabled Services professionals was 31% and pre-hypertension was 45.7%. The prevalence of stage-1 hypertension in the age group of 19-25 years was 18% and 23% in 26-30 years group while the prevalence of stage-2 hypertension in the age group of 19-25 years was 5% and 3% in 26-30 years group. The results indicate that dimensions of workplace autonomy and workplace environment are associated with hypertension. Conclusions: Hypertension affects the young urban Indians a decade earlier compared to available evidence. Furthermore, there is an association of autonomy and work-environment with hypertension. This signifies further exploration of underlying endocrine mechanisms. Funding: The funding UCLA International Research and Training Program and the Public Health Foundation of India provided the funding for this study. Results: The study was supported through Fogarty/UCLA International Research and Training Program (Grant Number: D43 TW000013) and the Public Health Foundation of India
Keywords: Hypertension in India, hypertension in young urban subjects, job stress
|How to cite this article:|
Babu GR, Mahapatra T, Detels R. Job stress and hypertension in younger software professionals in India. Indian J Occup Environ Med 2013;17:101-7
|How to cite this URL:|
Babu GR, Mahapatra T, Detels R. Job stress and hypertension in younger software professionals in India. Indian J Occup Environ Med [serial online] 2013 [cited 2022 Jan 22];17:101-7. Available from: https://www.ijoem.com/text.asp?2013/17/3/101/130848
| Introduction|| |
Hypertension is a major contributor to the world-wide epidemic of cardiovascular disease (CVD).  It is estimated that hypertension causes 7.5 million deaths world-wide amounting to 12.8% of the total of all annual deaths.  Many risk factors leading to hypertension are modifiable and therefore provide an opportunity for preventive efforts.  Hence any intervention that can successfully prevent or reduce hypertension should be viewed as promoting cardiovascular health of individuals. There is an imperative need for population-based research to understand the social determinants at the community level influences about choices and options for people to adopt particular behaviors such as smoking.  Workplace settings provide opportunities to explore determinants of these negative behaviors. 
Job stress is defined as "A set of psychosocial factors experienced by workers due to work conditions, generated as composite experiences at different levels within an organization." Among environmental factors, job stress is an important determinant of hypertension and is well-studied in developed countries.  It is very important to understand the role of stress at the organizational level and understand how this relates to hypertension in low and middle-income countries (LMIC) such as India. It is estimated that in LMIC, a smaller proportion of a healthy workforce will have to bear responsibility for a large and increasingly aging population.  Hence public health researchers in these countries need to recognize the window of opportunity to address factors that can reduce CVD risk at workplaces. ,,
It is known that workers in the Information Technology (IT) and Information Technology Enabled Services (ITES)  sectors are predisposed to several cardiovascular risk factors. , However, there are no studies done in India that document job stress and its association to hypertension among the IT/ITES professionals. We conducted a cross-sectional study among professionals working in IT and ITES sectors. In this study, we estimated prevalence of job stress and its association with hypertension. Understanding the prevalence's of job stress and other risk factors within this specialized workforce can help to prevent morbidity related complications. Identification of risk profiles in this workforce can guide worksite interventions to prevent debilitating conditions thereby improving the productivity of the workforce.
| Materials and Methods|| |
A detailed description of methods in the study is provided in our earlier paper on methods.  Pertinent important portions of methods are presented in this paper. The source population comprised all IT/ITES professionals aged 20-59 years working in "technical functions" in 21 selected worksites (units) of the IT/ITES sector willing to join the study. We conducted a cross-sectional study of IT/ITES professionals in Bangalore, third largest in India by population and the IT capital of India. , In 2011, Bangalore had more than 1000 IT/ITES companies in which greater than 150,000 IT/ITES professionals worked. , We followed mixed methods sampling strategy having an initial stage of probability sampling followed by the final stage of purposive sampling was used to select the IT/ITES professionals for this study. Detailed methods paper is published earlier.  The first stage involved a stratified sampling (quota sampling) to select the geographic clusters of IT/ITES companies scattered in Bangalore and in the second stage, individual IT/ITES unit within each selected clusters based on purposive sampling techniques. ,, The sampling was done such that there was at least one unit representing every geographical area having IT/ITES companies in Bangalore.  Thus from 17 selected geographic clusters 21 worksites (units) were selected. In each unit, after obtaining necessary administrative permissions, eligible employees were recruited after providing informed consent.
Using the sample size calculation formula: N = [Z1-α/2] 2p (1-p)/d2, provided by Daniel,  using a sample size calculator,  assuming 10% background prevalence of hypertension (p) based on evidence, significance level of 0.05 (α), desired precision of 0.02 (d) and assuming 20% of non-response, the required sample size was 1037 participants. However, we invited 1305 IT/ITES workers to participate, out of whom 1071 participated in the study: (509 subjects were from the IT sector and 472 subjects from ITES sector). 
The study was anonymous, and no names or other personal identifying information were collected from the participants. Each participant was assigned a unique number that linked individual information of the participants for the purpose of the analyses. Quiet private rooms provided by IT/ITES companies were used for collection of information for both qualitative and quantitative phases. The study was reviewed and approved by the UCLA Institutional Review Board (IRB, #G09-12-002-01, IRB#10-001348) and the ethics committee of the Public Health Foundation of India (TRC-IEC 40/10).
A job stress questionnaire was self-administered to collect information on job stress and other risk factors. Specifically, we used two different types of exposure assessments. The first measure was the occupational stress index,  a validated, reliable and tested measure that has pre-defined specific domains of job stress. Secondly, we identified contextual stress domains based on our qualitative study.  These contextual domains would better describe the stressful conditions of the IT/ITES industry as information regarding these domains was directly collected from the professionals. These are time pressure, length of experience, shift work, job control, income, autonomy, appreciation of work, physical environment, work-environment and affect. The details regarding estimation of each domain is provided in our earlier publication.  The estimation of two domains is provided here are of focus in this paper. The autonomy domain of stress was estimated by calculating the weighted average of responses to questions on "who is in charge of deciding your work schedule?" "Who evaluates your work?" and "Is your work constantly monitored?" Here, each question had three responses. We calculated the sum of all three questions on a total of nine and multiplied by 100. Appreciation of work was estimated by estimating the weighted average of responses to questions "Is your good work appreciated or recognized at your workplace?" and "has the credit for your work is taken by your supervisor?" All the stress domains were coded such that for increasing order of contextual stress.
Schnall and Belkic have provided a detailed description of the importance of obtaining point estimates of blood pressure (BP) approximating ambulatory BP.  In their article, a new BP protocol is described for obtaining point estimates of BP while a subject is actually working (in contrast to the American Heart Association protocol for casual clinic BP recording, 1982).  We followed this protocol with slight modifications. The earlier protocol suggests three readings, but we took two readings due to practical feasibility and as per standard clinical practice in India. Furthermore, instead of taking an average of 1 st and 2 nd reading, we used only 2 nd reading. BP classification is done based on 7 th report of Joint National Commission (JNC-VII). 
We collected details on variables that might be associated with exposure and outcome variables under each of the hypotheses [Figure 1]. The variables specific to potentially confound the association of job stress and hypertension were included in the model for analysis. These are dietary intake, physical activity, tobacco use (ever and current), socio-economic status,  alcohol intake, shift work and leg length. 
The data from the cross-sectional survey was analyzed using SAS 9.1.3104 (Business Analytics and Business Intelligence Software. 100 SAS Campus Dr, Cary, NC 27513, United States).  We used ordinal logistic regression for all our estimates.
|Figure 1: Directed acyxlic graph depicting hypothesized association of job stress and hypertension|
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| Results|| |
The sample comprised of a total of 1071 subjects that included 599 IT professionals and 472 ITES professionals. After two readings and according to the JNC-VII classification,  the prevalence of pre-hypertension was 45.7%, of stage-1 was 25.43% and stage-2 was 5% [Table 1]. By considering binary classification, the prevalence of hypertension was 31% [Table 1].
The prevalence of stage-1 hypertension in the age group of 19-25 years was 18% and 23% in 26-30 years group while the prevalence of stage-2 hypertension in the age group of 19-25 years was 5%, 3% in 26-30 years group [Table 2]. The prevalence in age groups of 31-35 years and of 36-55 years is also of interest, but it is worth to be noted that the number of persons in this age group is very low.
|Table 2: Distribution of age groups and prevalence of hypertension in IT/ITES professionals|
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The results of the logistic regression estimating total unadjusted prevalence association between contextual stress domains with hypertension are presented in [Table 3]. Keeping 19-25 years as the reference group, the odds of getting hypertension for 31-35 years old professionals was 48% lower and for 36-55 years was 60% lower [Table 4].
|Table 4: Crude estimates for age groups with hypertension in IT/ITES professionals|
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On adjusting for age, gender, waist by hip circumference, family history of high BP, socio-economic status, marital status, tobacco ever use, regular exercises for at least 20 min daily and alcohol use, the results for higher stress for contextual domains were statistically significant for autonomy and work-environment, whereas results for other contextual stress domains were not statistically significant. People with moderate autonomy had 40% higher and with high work-environment stressors had 48% chances of having hypertension compared with lower level of stress [Table 3], [Table 4], [Table 5].
|Table 5: Adjusted estimates of hypertension (JNC‑VII, 2nd readings) with contextual domains of job stress|
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| Discussion|| |
We report the results of a moderately large study (N = 1071) of the prevalence of hypertension among IT professionals in the Indian subcontinent employed at 27 different IT companies in and around Bangalore. The focus of our study is on the age gradient of hypertension prevalence as well as exploring the association of psychosocial predictors of risk related to workplace stress. This establishes higher prevalence of hypertension in the younger age cohort. Our earlier work has established that several work stressors are not associated with hypertension.  In this study, we report that the dimensions of workplace autonomy and workplace environment are associated. We report that moderate level of autonomy has a higher degree of association with prevalence of hypertension.
There is very high prevalence of hypertension in the study population. It is alarming that around 31% of IT/ITES professionals are hypertensive with approximately 5% having malignant levels of hypertension. South Asians are predisposed to be hypertensive a decade earlier compared the developed countries. ,, Our study suggests that hypertension in IT/ITES professionals occurs a decade earlier compared to the rest of India and two decades earlier compared to developed countries.  This suggests that if untreated, these professionals would go on to develop CVD at an early age. The results also indicated that 46% of professionals were in pre-hypertension. According to the JNC-VII classification, pre-hypertension is not a disease category but a designation chosen to identify individuals at high-risk of developing hypertension.  These individuals will have to change their lifestyle to prevent a progressive rise in BP using the recommended lifestyle modifications. 
CVD are a major cause of mortality and disease in the Indian subcontinent, causing more than 25% of deaths. It has been predicted that these diseases will increase rapidly in India and this country will be the locale of more than half the cases of heart disease in the world within the next 15 years. High BP is the predominant risk factor for CVD and evidence indicates that there is a high prevalence in both urban and rural areas. Indian urban population-based studies using World Health Organization guidelines for diagnosis have shown increasing hypertension among adults aged 20 years from about 5% in the 1960-70s to 11-15% in the late 1990s. , There were several studies done in India suggesting increasing trends in the prevalence of hypertension in urban subjects over the last four decades compared to the people in rural areas. ,,,,,, Our results are in conformity with earlier results in the general population but suggest that IT/ITES professionals are at higher-risk to get hypertension and are affected a decade earlier compared to earlier available evidence.
The results from this study indicates, that there is a higher prevalence of hypertension among professionals in the early years of joining IT/ITES sectors compared to professionals who worked for more than 12 years. It was seen that the longer the professionals work, lower is the odds of getting hypertension. It is counterintuitive to have lower prevalence of hypertension with an increase in experience in IT/ITES professionals. The reason for this can be that the interplay of cardiovascular risk factors and job stress might result in the IT/ITES professionals getting hypertension in earlier years, as soon as they join the workforce. However, in due course of time, it might be possible that the professionals with hypertension leave the workforce. We cannot also rule out the likelihood of survivor bias as the professionals with hypertension might have developed coronary heart disease or changed jobs or might have succumbed to death. It might also be possible that workers who prefer to stay back in the organizations might gradually adapt to better coping mechanisms.
Specifically, subjects with autonomy related stress and higher work-environment related stresses were found to have a higher prevalence of having Hypertension compared to the participants with their corresponding lower levels of stress. The autonomy domain of stress was estimated by calculating the weighted average of responses to questions on "Who is in charge of deciding your work schedule?" "Who evaluates your work?" and "Is your work constantly monitored?"
In our study, the autonomy stressor domain comprised information on work schedule, evaluation of work and monitoring of the work. Earlier studies support these findings. , In our recent meta-analysis, we detected that job strain and hypertension were positively associated in studies judged to have better methodological quality, which depended heavily on the methods of exposure and outcome ascertainment.  Our study is in conformity with the available evidence. The paucity of research exploring the association between job stressors and hypertension in India necessitates the replication of these results in other occupational groups including IT/ITES professionals. In particular, further exploration is necessary to understand how stress factors are related to overarching social determinants and how this might be related to their health status.
We found a high prevalence of hypertension in the study population. The hypertensive professionals need to be followed-up to prevent CVD. There is a great opportunity for the primary prevention of (CVD) through the creation of awareness among IT/ITES professionals. The message to these professionals should focus on making lifestyle changes and continuously monitor BP. It is important to educate the professionals to engage in habits, which reduce the risk of hypertension such as regular exercises and necessary dietary modifications to prevent the onset of serious, life-threatening complications. Further, effective preventive programs will have to be designed to prevent hypertension in high-risk groups in India. The policymakers should be urged to provide resources to pilot intervention programs addressing primary prevention of hypertension.
The positive impacts on health of working professionals can be achieved through working and collaborating with workers and employers. It would be in the best interest of the companies to focus on the long-term sustainable approaches and to urge engage employees to adjust healthy lifestyles to achieve a reduction of non-communicable diseases. The employers of IT/ITES should realize that small investments made in preventive activities will translate to saving expenses for the company and better health, thereby sustained productivity of their employees.
The association of autonomy and work-environment with hypertension suggests that our results are in conformity with research on social determinants of health. Future research should focus on delineating the exposure and health status contrasts between two or more occupational groups. Attention should be paid toward prospective examination of the variance in induction periods and pathways connecting health outcomes and behaviors. Concurrently, worksite interventions can be piloted that aim at reducing psychosocial aspects of work-environment and autonomy domains including professional help on stress-management.
There is evidence that renin-angiotensin - aldosterone system and catecholamine adaptations in persons with hypertension. In general, circulating levels of cortisol, epinephrine and norepinephrine and urinary norepinephrine excretion tend to be higher in patients with essential hypertension than in normotensive subjects. It is also evident that stress leads to higher levels of epinephrine. Hence, it is worth investigating whether the susceptibility of Indians for hypertension at a younger age is because of the way the endocrine system is regulated in them. The current study spurs the idea to explore the underlying endocrine mechanism in young Indians having hypertension.
| Funding|| |
The study was supported through NIH/Fogarty International center, Fogarty/UCLA AIDS International Research and Training Program (Grant Number: D43 TW000013) and the Public Health Foundation of India provided partial grant.
| Acknowledgments|| |
The authors would like to thank Shanthkumar for the help with field components of research, Wendy Aft for work on ethical approval and TS Ramesh for administrative support.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
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