|Year : 2018 | Volume
| Issue : 4 | Page : 144-147
A study on estimating the cardiovascular disease risk among medical students in central Kerala: The INTERHEART method
Asif Ajmal Ameer Khan* MBBS, 1, Akesh Thomas* MBBS, 2, Nesrin Muhamed MBBS, 1, Vimal Prakash Jayaprakash MBBS, 1, Janki Dutt MBBS, 1, Shwetha M Sajeev MBBS, 1
1 Department of Cardiology, Sree Narayana Institute of Medical Sciences, Kunnukara, Kerala, India
2 Department of Emergency Medicine, Sree Narayana Institute of Medical Sciences, Kunnukara, Kerala, India
|Date of Web Publication||15-Oct-2018|
Dr. Akesh Thomas*
Poovannal, Nedumkandam, Idukki - 685 553, Kerala
Source of Support: None, Conflict of Interest: None
Background: The incidence of cardiovascular disease (CVD) in India is increasing at an alarming pace. Professionals with high-job stress and a sedentary lifestyle are at a great risk of developing CVD. Medical students are a population with very high level of stress and less time for exercise. Aim: The aim of this study is to estimate the prevalence of CVD risk among medical students and to compare with that of same age general population. Setting and Design: A cross-sectional study in the suburb of Ernakulam district of South India. Materials and Methods: A cross-sectional survey using standardized interviews along with measurement of blood pressure and waist/hip ratio among medical students and the general population. CVD risk for both groups calculated using the nonlaboratory-based INTERHEART modifiable risk score. Results: A total of 1014 people participated in the study (mean age: 21.3 ± 1.3), among which 396 were medical students and 618 were age-matched general population. Overall, 17.8% were found to have a moderate risk of CVD, and 2.8% were found to have high risk of CVD. Among medical students, 21% were at moderate risk for CVD (vs. 14.6% in general population, P = 0.01), similarly, 2.8% of both groups were at high risk for developing CVD (P = 1.0). Medical students had significantly lower prevalence of smoking (4% vs. 13.4%, P ≤ 0.001) and were physically more active than the general population (86.04% vs. 70.9%, P ≤ 0.001). There were no significant differences in the two groups regarding the other risk factors. Conclusion: The risk of CVD among both the medical students and age-matched general population are high in central Kerala; however, the medical students are not at a significantly increased risk than the general population.
Keywords: Cardiovascular disease risk, INTERHEART study, Kerala, medical students, South India
|How to cite this article:|
Ameer Khan* AA, Thomas* A, Muhamed N, Jayaprakash VP, Dutt J, Sajeev SM. A study on estimating the cardiovascular disease risk among medical students in central Kerala: The INTERHEART method. J Clin Prev Cardiol 2018;7:144-7
|How to cite this URL:|
Ameer Khan* AA, Thomas* A, Muhamed N, Jayaprakash VP, Dutt J, Sajeev SM. A study on estimating the cardiovascular disease risk among medical students in central Kerala: The INTERHEART method. J Clin Prev Cardiol [serial online] 2018 [cited 2019 May 21];7:144-7. Available from: http://www.jcpconline.org/text.asp?2018/7/4/144/243253
FNx01Both authors contributed equally to this work.
| Introduction|| |
Cardiovascular disease (CVD) is the leading cause of mortality worldwide. CVD, especially coronary artery disease (CAD) has assumed epidemic proportion in India, similar to the world statistics. It is now the leading cause of mortality in India. The age-standardized CVD death rate of 272/1,00,000 population in India is higher than the global average of 235/1,00,000 population. The years of life lost attributable to CVD in India increased by 59% from 1990 to 2010 (23.2 million–37 million).
It is a long-known fact that CAD is a chronic process that begins during early years of life and slowly progresses throughout life., Busy professionals including the health-care professionals are at an increased risk of developing CVD due to the lack of exercise and stress associated with the professional job. Medical students are no exception to this; the stress associated with the intense training in medical school along with lack of exercise put the students at risk of developing CVD at an earlier age. Various studies have previously shown a significant difference in the incidence of CVD among different occupations.,
Early interventions are the key to preventing CVD. Various tools have been studied for the assessment of cardiac risk in the general population. Framingham risk score is the most popular and most widely used score to predict the CVD risk. It is based on the Framingham Heart Study, one of the most extensive and fruitful studies in the history of modern medicine. Other major CVD risk predicting scores are American College of Cardiology/American Heart Association (ACC/AHA) Pooled Cohort risk equations (ACC/AHA model), Reynolds risk score, systematic coronary risk evaluation, the World Health Organization risk charts, and the Lancet chronic diseases risk charts. Various studies compared the different CVD risk prediction tools, and most of them concluded that the scores vary significantly in a population and among different populations in predicting CVD risk. The INTERHEART study emerged as a solution for this, the study was done in 52 countries including low- and average-income countries where the burden of CVD is much higher than the developed nations. It concluded that the score can be used worldwide in different ethnic groups without much difference in the calculated risk.
The INTERHEART study was a case–control study conducted over a period of 4 years in 262 centers from 52 countries. It concluded that nine modifiable risk factors were associated with the risk of CVD including smoking, raised apoB/A1 levels, history of hypertension, diabetes, abdominal obesity, psychosocial factors, daily consumption of fruits and vegetables, regular alcohol consumption, and daily physical activity. The study formulated four scoring system for the calculation of CVD risk, the short INTERHEART Modifiable Risk Score (IMRS), full IMRS, cholesterol risk score, and the nonlaboratory-based IMRS. The nonlaboratory-based IMRS showed accuracy comparable to the laboratory-based IMRS and was promising to be used in a resource-poor setting such as India. Since then, the IMRS score was used to find out the cardiac risk of different populations.
Data of cardiovascular risk factors among young adults in South India are lacking. Here, in this study, we are calculating the cardiovascular risk among medical students in Kerala, India, using the nonlaboratory-based IMRS. We are also trying to create awareness and help in implementing preventive strategies in the population.
| Materials and Methods|| |
Ethics Committee Approval was obtained from the Institutional Review Board of the parent institution. Students from a medical college located in the suburban area of Ernakulam district of South India were selected for the study; age-matched individuals from the general population were selected from the same suburban area. The nonlaboratory-based IMRS score for each participant is calculated in separate pro forma after conducting a thorough one-to-one interview with each participant, along with calculation of waist-to-hip ratio (WHR) and measurement of blood pressure (BP). Medical Students older than 35 years were excluded from the study.
The following information were collected from each participant: information regarding family history of onset of CAD in any of the parent before the age of 60 years, lifestyle habits such as smoking and alcohol consumption, psychosocial factors, dietary factors, and physical activity.
Waist circumference (WC) was measured to the nearest 0.1 cm at the midpoint between the tip of the iliac crest and last costal margin in the back and at umbilicus in the front using a nonstretchable measuring tape at the end of the normal expiration with the participant standing erect in a relaxed position. The hip circumference was measured around the widest portion of the buttocks.
BP was measured using mercury sphygmomanometer in the right upper arm in the supine position after 5 min of rest. Reading of phase-I Korotkoff sound was taken as systolic BP and phase-v as diastolic BP, respectively. BP was measured three times with 30 s interval. The average of second and third measurements was used in the analysis.
Participants who were found to have hypertension and those giving a history of diabetes mellitus were advised a medical consultation. All the participants were given awareness on CVD risk factors and advice was given regarding necessary lifestyle modifications.
For the purpose of the study, hypertension was defined according as BP ≥140/90 mmHg as recommended by the panel appointed to Joint National Commission 8.
WC ≥80 cm in females and ≥90 cm in males were considered as abnormal. WHR ≥0.90 in males and ≥0.85 in females were considered as abnormal.
| Results|| |
The data collected were analyzed using statistical software (SPSS (IBM, New York, USA) and R), Fisher's exact test and Chi-square test were used for the analysis of the data.
A total of 1014 participants participated in the study (mean age: 21.3 ± 1.3 [standard deviation]). Among which 396 were medical students (mean age: 21 ± 1.2) and 618 were age-matched general population (mean age: 21.5 ± 1.4), with P = 0.99. Among the total study population, 612 were male and 402 were female. On analyzing the data for the entire study group, 79.5% (n = 813) were found to have low risk for CVD as per the IMRS (score = 0–9), 17.8% (n = 173) were found to have a moderate risk for CVD (score = 10–15), and 2.8% (n = 28) were found to be at high risk for developing CVD (score >15).
On comparing the data of the two groups (medical students vs. general population), the results obtained are 76.3% (n = 302) medical students are at a low risk for developing CVD (vs. 82.7% general population, n = 511 with P = 0.014), 21% (n = 83) medical students were at moderate risk for CVD (vs. 14.6% general population, n = 90 with P = 0.01), and 2.8% (n = 11) medical students were found to have a high risk for CVD (vs. 2.8% general population, n = 17 with P = 1.0). Although a higher proportion of medical students were found to be at moderate risk of developing CVD than the general population, the difference was not statistically significant on analysis (P = 0.030).
The prevalence of modifiable risk factors among medical students and general population are as follows: 96% medical students (n = 580) reported they never smoked (vs. 86.6% general population, n = 535) (P < 0.001), 0.5% medical students were former smokers (vs. 7.8% general population) (P < 0.001), 3% medical students reported to exposure to passive smoking (vs. 15.4% general population) (P < 0.001), and 86.4% medical students reported to have daily physical activity (vs. 70.9% general population) (P < 0.001). Other risk factors such as diabetes mellitus, hypertension, family history of CVD, WHR, psychosocial stressors including general stress or depression, daily consumption of fruits, daily consumption of vegetables, meat or poultry consumption two or more times daily, and consumption of deep-fried or fast food three or more times a week did not show any significant difference between the two groups [Table 1] and [Figure 1], [Figure 2].
|Figure 1: Dietary habits of medical students versus general population (in percentage)|
Click here to view
|Figure 2: Physical activity level reported among medical students versus general population (in percentage), P ≤ 0.001|
Click here to view
| Discussion|| |
Analysis of the results revealed that there is no significant difference in the CVD risk of medical students and age-adjusted general population. Although the cumulative risk is same in both groups, they possess a different proportion of risk factors. Medical students were found to have decreased risk from smoking, consumption of fried and salty food, and they were also trying to maintain good health by consuming more fruits and vegetables. Medical students were also more active physically compared to the general population. On the other side, medical students were found to have an increased risk of CVD from hypertension, feeling of sadness or depression, and from an unfavorable family history. However, on statistical analysis of the data, only smoking and level of physical activity were found to be significantly different among both groups. From these data, it can be assumed that medical students are more aware of CVD risk factors and they are trying to maintain a good health compared to the general population of the same age. The risk factors which were not so easy to control were the ones found increased in medical students such as hypertension and feeling of sadness or depression.
A previous study done to find out the prevalence of CVD risk among the South Indian medical students by Paul et al. concluded that there is an increased risk of CVD risk among the medical students of South India. Kurian et al. also reported similar results in 2015. Our study cannot be compared to the above-mentioned studies directly since we used a different set of variables for the study. Both the previous studies were limited to medical students, and they were not compared to an age-matched general population. Here, we found that the medical students are at significant risk of CVD although not as high as found in the previous studies, more importantly, we found that the same age general population is at a similarly high risk of CVD. The probable reasons why the previous studies found a higher risk of CVD compared to our study are as follows: (1) they were done in a more urban setting while our study is in a suburban area, the lifestyle of students from an urban medical school may involve more junk foods and less physical activity and (2) they were done in top-tier medical schools where the students are having a much busy schedule and may be more stressed than the students in a mid-to-low tier medical school.
Although the risk of CVD in medical students during their student period is similar to that of the general population, there is an obvious chance of increased risk in the future; residents and fellows are having a busier schedule and more stressful life compared to medical students, the medical students may show an increase in risk from present values once they graduate and begin residency training. The same is true for practicing clinicians; most clinicians report stress at work and reduced physical activity., The amount of stress and burnout experienced by physicians varies based on their specialty and the type of practice; surgeons and emergency physicians report a high rate of burnout, while primary care physicians and dermatologists report very low rate of stress related to the job. In a resource-poor setting like India, the physicians will be at an increased stress at job and probably will be getting less time for exercise compared to their counterparts in the developed countries.
The authors recommend that the health promotional activities targeting adolescents and young adults should be implemented in the community and also medical students should be trained to cope with their stress.
The study was limited by the following facts: the study participants mostly included college students and may not represent the lower socioeconomic class. There is a possibility of withholding the information related to smoking and drinking due to the social stigma associated with drinking alcohol beverages and smoking in the Indian community.
The study was conducted in a suburban area; it may not represent the trend of an urban medical school or of a rural medical school. The medical school selected for the study was a mid-tier medical school; this may not be a representative sample of top-tier medical schools where students are busier and more stressed. The dietary patterns were self-reported by the participants, this may not be completely accurate. Similarly, there was no specific quantity of salt defined with the variable salty food, so the reported consumption of salty food may not be fully accurate.
| Conclusion|| |
From our study, it can be concluded that the burden of CVD risk among both medical students and age-matched general population are high in central Kerala; however, the medical students are at no significantly increased risk than the general population. The medical students possess a different set of risk factors compared to that of the general population; the risk of CVD from smoking is significantly lower among medical students compared to general population and medical students are physically more active than the general population.
We would like to thank the Department of Statistics, Sree Narayana Institute of Medical Sciences. The authors would also like to thank Dr. Jaydeep C. Menon for his guidance during the entire study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Srinath Reddy K, Shah B, Varghese C, Ramadoss A. Responding to the threat of chronic diseases in India. Lancet 2005;366:1744-9.
Hong YM. Atherosclerotic cardiovascular disease beginning in childhood. Korean Circ J 2010;40:1-9.
Berenson GS, Srinivasan SR, Bao W, Newman WP 3rd
, Tracy RE, Wattigney WA, et al.
Association between multiple cardiovascular risk factors and atherosclerosis in children and young adults. The Bogalusa heart study. N Engl J Med 1998;338:1650-6.
Morris JN. Occupation and coronary heart disease. Arch Intern Med 1959;104:903-7.
Pereira MA, Kriska AM, Collins VR, Dowse GK, Tuomilehto J, Alberti KG, et al.
Occupational status and cardiovascular disease risk factors in the rapidly developing, high-risk population of Mauritius. Am J Epidemiol 1998;148:148-59.
Hajar R. Framingham contribution to cardiovascular disease. Heart Views 2016;17:78-81.
] [Full text]
Bazo-Alvarez JC, Quispe R, Peralta F, Poterico JA, Valle GA, Burroughs M, et al.
Agreement between cardiovascular disease risk scores in resource-limited settings: Evidence from 5 Peruvian sites. Crit Pathw Cardiol 2015;14:74-80.
Cook NR, Paynter NP, Eaton CB, Manson JE, Martin LW, Robinson JG, et al.
Comparison of the Framingham and Reynolds risk scores for global cardiovascular risk prediction in the multiethnic women's health initiative. Circulation 2012;125:1748-56, S1-11.
Yusuf S, Hawken S, Ounpuu S, Dans T, Avezum A, Lanas F, et al.
Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): Case-control study. Lancet 2004;364:937-52.
McGorrian C, Yusuf S, Islam S, Jung H, Rangarajan S, Avezum A, et al.
Estimating modifiable coronary heart disease risk in multiple regions of the world: The INTERHEART modifiable risk score. Eur Heart J 2011;32:581-9.
Kovell LC, Ahmed HM, Misra S, Whelton SP, Prokopowicz GP, Blumenthal RS, et al.
US hypertension management guidelines: A review of the recent past and recommendations for the future. J Am Heart Assoc 2015;4. pii: e002315.
Paul B, Nayaaki V, Sen M, Isaac R. Prevalence of cardiovascular disease risk among medical students in South India. Indian J Community Health 2015;27:211-5.
Kurian S, Manjula VD, Zakariah JA. A study on cardiovascular risk factor profile of medical students in a tertiary care hospital of central Kerala. Natl J Med Res 2015;5:11-7.
Saijo Y, Chiba S, Yoshioka E, Kawanishi Y, Nakagi Y, Ito T, et al.
Job stress and burnout among urban and rural hospital physicians in Japan. Aust J Rural Health 2013;21:225-31.
Bernburg M, Vitzthum K, Groneberg DA, Mache S. Physicians' occupational stress, depressive symptoms and work ability in relation to their working environment: A cross-sectional study of differences among medical residents with various specialties working in German hospitals. BMJ Open 2016;6:e011369.
[Figure 1], [Figure 2]