|Year : 2017 | Volume
| Issue : 1 | Page : 14-18
Smoking status and its effect on blood pressure: A study on medical students
Sunil Kumar Jena, Kanhu Charan Purohit
Department of Physiology, Veer Surendra Sai Institute of Medical Sciences and Research, Burla, Odisha, India
|Date of Web Publication||19-Dec-2016|
Sunil Kumar Jena
Department of Physiology, Veer Surendra Sai Institute of Medical Sciences and Research, Burla - 768 017, Odisha
Source of Support: None, Conflict of Interest: None
Background: Hypertension is a potent modifiable risk factor to develop various cardiovascular diseases. Cardiovascular diseases are the leading cause of death in the world. Cigarette smoking is one of the risk factors of hypertension. Materials and Methods: This was a case-control study, in which young smokers were selected as case and young nonsmokers were as control. A total 111 male MBBS students were selected, divided into two groups - smoker and nonsmoker. Smoker group included 63 current cigarette smokers and 48 nonsmokers. All participants were within 20-25 years of age. Blood pressure (BP) was recorded in the morning between 7 and 8 am by auscultatory method. Results: Minimum and maximum duration of cigarette smoking were 1 year and 13 years. Minimum and maximum number of cigarettes smoke per day were 2 and 12. Minimum and maximum pack year of smoking were 0.1 and 3.3. Mean systolic BP of smoker was 134 ± 10.6 mmHg and nonsmoker was 117 ± 7.5 mmHg. Mean diastolic BP of smoker was 84 ± 7.6 mmHg and nonsmoker was 80 ± 7.5 mmHg. Mean pulse pressure of smoker was 49.9 ± 7.3 mmHg and nonsmoker was 36.7 ± 6.5 mmHg. Among the smokers, only 6.35% were normotensive, 61.9% were prehypertensive, and 31.75% were hypertensive. Conclusion: This study suggested that even short duration of smoking with low pack year can increase BP if not prevented may lead to various cardiovascular diseases. Thus, young adults, the future of country should be motivated to avoid smoking for healthy life.
Keywords: Cardiovascular disease, cigarette smoking, hypertension, medical students
|How to cite this article:|
Jena SK, Purohit KC. Smoking status and its effect on blood pressure: A study on medical students. CHRISMED J Health Res 2017;4:14-8
|How to cite this URL:|
Jena SK, Purohit KC. Smoking status and its effect on blood pressure: A study on medical students. CHRISMED J Health Res [serial online] 2017 [cited 2019 Oct 19];4:14-8. Available from: http://www.cjhr.org/text.asp?2017/4/1/14/196034
| Introduction|| |
It is acceptable worldwide that cigarette smoking is the leading cause of preventable death all over the world. Recent statistical analysis tales that it will be very difficult to reduce tobacco-related deaths in next 30-50 years unless tobacco users are encouraged to quit.  The hazardous effects of cigarette smoking on general health are well documented, and there is evidence that cigarette smokers die 10 years younger than nonsmokers. , Cigarette smoking is a powerful addiction, so experimentation and uptake of smoking which typically occur in late childhood or adolescence.  Cardiovascular diseases are the leading cause of death is accepted globally.  Cardiovascular diseases contribute to one-third of death globally and are a leading cause of disease burden in developed and developing countries.  Cardiovascular diseases are eminently preventable diseases. Therefore, to reduce the burden of cardiovascular disease, the strategies should target the lifestyle-related risk factors such as unhealthy diet, tobacco smoking, physical inactivity as well as morbid conditions arise due to these factors such as hyperlipidemia, hyperglycemia, or hypertension. Hypertension is a preventable risk factor for cardiovascular disease which is very common health problem worldwide due to the contribution of risk factors such as cigarette smoking and physical inactivity. , Hypertension plays a major etiologic role in developing cerebrovascular disease, ischemic heart disease, and renal failure. Proper treatment of hypertension is essential to reduce the burden of diseases.  It is also studied that cerebrovascular disease, ischemic heart disease, renal failure, and other diseases are associated not only with hypertension alone but also with suboptimal blood pressure (BP).  Previous data suggest that cerebrovascular disease and ischemic heart disease occur in persons with suboptimal BP (systolic BP [SBP]>115 mmHg).  Several studies have been done to establish relation between cigarette smoking and BP. Some studies reported that cigarette smoking decreases BP; some reported smoking increases BP while others have reported that there is no association between smoking and BP. This study was proposed to find the smoking status of medical students and the effect of smoking on BP. Medical students are the future valuable health-care provider as well as health and wealth of the nation; they should have a healthy life. Thus, this study will help prevent the health hazardous of medical students as well as other young adults exposed to smoking.
| Materials and methods|| |
This study was conducted in department of physiology of a health institution in eastern India. This was a case-control study, in which young smokers were selected as case and young nonsmokers were as control. The study was approved by the local Institutional Ethical Committee. This study was completed between January 2016 and August 2016. MBBS students of this medical institution were taken as the participants for this study. A total 111 male MBBS students were selected, divided into two groups - smoker and nonsmoker. Smoker group included 63 current cigarette smokers and 48 nonsmokers. All participants were within 20-25 years of age. Students were explained the protocol and output of the study. They were making confident that the name of the participants will not be disclosed in public.
Selection of participants was done by history taking and general health checkup of MBBS students by the researchers. Smoker group included students who were current smoker with minimum 1-year history of cigarette smoking. Smokers with associated systemic disease, family history of hypertension, diabetes, and endocrinal diseases were excluded from this group. Nonsmoker group included students who have never smoked cigarette or use any other tobacco products. Students with associated systemic disease, family history of hypertension, diabetes, and endocrinal diseases were excluded from this group. Occasional smokers were excluded from either of the group. All participants including both smoker and nonsmoker were agreed to cooperate for study and gave their consent in written form. Data of duration of smoking in years and number of cigarettes smoke per day were collected from each smoker. These two data were helpful to calculate pack year by the following formula.
No. of pack years = No. of cigarettes smoked per day × No. of years smoked/20. 
The BP of each participant was recorded in auscultatory method by the instrument, i.e., elcometer sphygmomanometer. Participants were instructed to take normal diet along with to avoid any medication or drug previous night of BP recording. They were also instructed to take minimum 6-8 h of sleep of previous night of BP recording. BP was recorded in the morning between 7 and 8 am. Before recording, they were given 5-10 min of rest. Then, BP was recorded in sitting position, the right arm of the participant by auscultatory method. Three recordings were taken from each participant, and the average of three was taken both for SBP and diastolic BP (DBP). Pulse pressure (PP) was calculated from SBP and DBP (PP = SBP − DBP). BP of both smoker and nonsmoker was classified as normal, prehypertension, and hypertension according to the Joint National Committee 7.
Statistical analysis was done by statistical software SPSS 16 version (IBM Corporation, Armonk, New York, USA). Smoking status of smokers was analyzed by three parameters, i.e., years of smoking, number of cigarettes smoke per day, and pack year, and the data were expressed in minimum, maximum, and mean ± standard deviation form. BP of smoker and nonsmoker was compared by unpaired t-test. BP of smokers was analyzed and classified as normal, prehypertension, and hypertension. Smokers were distributed in groups, i.e., normal, prehypertension, and hypertension, and data were expressed in number and percentage form. P < 0.05 was considered to be significant. Generation of tables and graphs was done by Microsoft excel and word.
| Results|| |
This study was done to see the effect of cigarette smoking on medical students. All the participants recruited in this study were male and between the ages of 20-25 years. A total number of participants included in this study were 111, which included 63 smokers and 48 nonsmokers as shown in [Figure 1].
[Table 1] shows smoking habit of smokers. Minimum, maximum, and mean duration of cigarette smoking were 1 year, 13 years, and 3.84 ± 3.17 years, respectively. Minimum, maximum, and mean number of cigarettes smoke per day were 2, 12, and 3.79 ± 2.17, respectively. Minimum, maximum, and mean pack year of smoking were 0.1, 3.3, and 0.69 ± 0.66, respectively.
[Table 2] shows the comparison of BP between smoker and nonsmoker. Mean SBP of smoker was 134 ± 10.6 mmHg and nonsmoker was 117 ± 7.5 mmHg. This difference in BP was significant at P = 0.000. Mean DBP of smoker was 84 ± 7.6 mmHg and nonsmoker was 80 ± 7.5 mmHg. This difference in BP was significant at P value 0.011. Mean PP of smoker was 49.9 ± 7.3 mmHg and nonsmoker was 36.7 ± 6.5 mmHg. This difference in BP was significant at P = 0.000.
[Table 3] shows the distribution of smokers into different categories on the basis of severity of BP. Out of 63 smokers, 4 had normal BP which accounts only 6.35% smokers, 39 were prehypertensive which accounts 61.9% of smokers, and 20 were hypertensive which accounts 31.75% of smokers.
| Discussion|| |
The researchers were proposed to find the status of cigarette smoking of medical students and its effect on BP. Medical curriculum is quite stressful due to heavy course, to excel in the examination, fear of failure as well as peer pressure. Because of curricular stress, wrong friendship, or for luxury, some medical students may start cigarette smoking. In this study, we found that out of 63 smokers, only one student had started cigarette smoking from very early age while rest started smoking after entering into this curriculum. Therefore, most of the smokers were short duration smokers. Hence, the pack year calculated was not so high. Hence, this study reported that these smokers were all light smokers. Large numbers of studies were done on cigarette smokers, but very fewer studies were done to see the effect of light smoking on BP.
A lot of studies were done to find the effect of cigarette smoking on BP, and a lot of controversies were there. Some studies reported smoking rises BP; some reported smoking decreases BP while some reported no effect. However, this study reported that SBP, DBP, and PP of smokers were more than nonsmokers. Further detail analysis of BP of both smoker and nonsmoker was done. We found that all nonsmokers (100%) had normal BP while 6.35% smokers had normal BP, 61.9% smokers had prehypertension, and 31.75% smokers had hypertension.
Various researchers have suggested the different effects of cigarette smoking on BP. Some suggested that there is no association between smoking and BP. ,, Some suggested that BP of smokers was lower than the BP of nonsmokers ,, while others suggested that smoking increases BP. ,, In one study, the researchers in their study demonstrated the effect of cigarette smoking on BP. They reported that there is increase in systolic as well as DBP along with heart rate (HR) after cigarette smoking whether tie cigarettes are of low-nicotine cigarettes or high-nicotine cigarettes. 
Autonomic imbalance in smokers can be linked to the effect of nicotine-mediated stimulation of autonomic ganglia and adrenal medulla resulting in increased discharge in cardiac sympathetic fibers. This enhanced sympathetic activity increases HR, BP, and myocardial contractility by acting on β1-adrenergic receptor and also increases coronary vasomotor tone by acting on α2-adrenoceptor. ,,, Some studies reported that PP is a better predictor of arterial wall stress due to BP than SBP and diastolic pressure. An increase in PP creates more stress on the arterial wall and left ventricle. The increase stress leads to damage of the blood vessels and ventricular hypertrophy. Damage to blood vessels leads to more chance of the development of atherosclerosis, thrombosis, and heart failure. , This study reported that the mean PP of smokers was higher than nonsmokers. Association between cigarette smoking and a wide PP may reflect either an increased peripheral resistance in smokers or the presence of aortic atherosclerosis and arterial inelasticity as smoking is a risk factor for atherosclerosis. 
| Conclusion|| |
A lot of studies have been done to establish the association between smoking and BP, but there are lots of controversies results. Most of the previous studies reported the effect of long duration of smoking with high pack year on BP. However, this study reported the effect of short duration of smoking with low pack year on BP and obtained the result of increased BP in smokers. This study can be helpful for making preventive strategies toward healthy life of young adults.
It is a pleasure for the researchers to acknowledge the students satisfactory cooperation in this study without whom this study could not be accomplished. We are also thankful Siddhartha Pati of the 1 st year MBBS student of Veer Surendra Sai Institute of Medical Sciences and Research, Burla, Odisha, India, for substantial contribution for this study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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