Prevalence of Pre-hypertension and nsion in Rural Tamil Nadu Populations A Pilot Study Report from Pandithamedu of Paiyanoor Village of Kancheepuram, Tamil Nadu, India Rekha Govindan #, Vikas Kumar 1, Dolly 1, Imran Shaikh Gouse Basha 1, Rahul Kumar V 1 and Rana Ranvijay Singh 1 # Corresponding author: Associate Professor, rekhagovindan2000@yahoo.com 1 Department of Biotechnology, Aarupadai Veedu Institute of Technology, Vinayaka Missions Unirsity, Paiyanoor, Abstract- Community based cohort studies from different parts of the world for a period of three to six decades showed an increase in the prevalence of hypertension about 30 times among the urban dwellers and by about 10 times among the rural inhabitants. Prevalence of hypertension in India as cited in literatures has been on an increasing trend. Hower most of the studies are from urban population. More studies are needed based on rural Indian scenario. The high frequency of pre-hypertension and hypertension are ry closely associated with the epidemic of cardiovascular and renal diseases. Evidences suggest that control of hypertension not only reduces the risk of cardiovascular diseases, but also slows down the progression of chronic kidney diseases. With this background, the present study was conducted from a rural population of Tamil Nadu to study the prevalence of hypertension as well as to increase the awareness on the importance of life style modifications. Such studies in the nearby villages of our institution indicate a high prevalence of pre-hypertension and hypertension among the rural populations. Key words: nsion, Pre-hypertension, Rural populations of Tamil Nadu INTRODUCTION World Health Day is celebrated on 7 th April to mark the annirsary of the founding of World Health Organization (WHO) in 1948. Er year a theme is selected for World Health Day that highlights a priority area of public health concern all or the world. This year in 2013, the theme for World Health Day is high blood pressure, also known as raised blood pressure or hypertension. It increases the risk of heart attacks, strokes and kidney failure. If left uncontrolled, high blood pressure can also cause blindness, irregular heartbeat and heart failure (Madhukumar et al., 2012). The present accepted definition for nsion is systolic blood pressure (SBP) which is more than or equal to 140mmHg and diastolic blood pressure (DBP) more than or equal to 90mmHg. nsion is an important public health problem in deloping countries especially in adults, aged 40-55 years (Gupta, 2004). Case control and community based studies among Indians show a high prevalence of hypertension in both urban and rural areas (Deepa et al., 2003; Mohan et al., 2008; Madhukumar et al., 2012). Though seral reports on the prevalence of hypertension ha been extely carried out in the urban populations, from rural south India ry few studies ha reported the prevalence and risk factors of hypertension. We conducted a sury at Pandithamedu, a subvillage under Paiyanoor village, Thiruporur tehasil, Kancheepuram district of Tamil Nadu. The study was done in association with the NSS unit of AVIT and Vinayaka Missions Chennai Hospitals, Paiyanoor. Systolic and Diastolic values were collected from participants enrolled for the study and the prevalence of hypertension was estimated. Through this study we also ga general awareness on hypertension, the significance and its association with various diseases such as cardiovascular and kidney diseases. METHODOLOGY For physical examination, standardized calibrated mercury column type sphygmomanometer and stethoscope, was used. nsion was diagnosed as per US Senth Joint National Committee on Detection, Evaluation and Treatment of nsion (JNC VII, 2004) criteria. Optimal Blood Pressure : <5/80 Normal Blood Pressure : <120/80 Pre-nsion : 121-139/80-89 Stage 1 nsion : 140-159/90-99 Stage 2 nsion : >160/100
Measurement of BP was performed after a 5 min period of rest using a mercury sphygmomanometer, and two BP readings was taken from both arms at 30 s intervals. In case if the two readings differed by or 10 mm of Hg, a third reading was obtained, and the three measurements were araged. The Korotkoff sounds phase I (the pressure at which the sounds were first heard) were taken as the Systolic Pressure (SBP) and the phase IV sounds (the pressure at which the sounds were first muffled and then disappeared) were taken as the Diastolic Pressure (DBP). Data entry and statistical analysis were performed using Microsoft Excel and SPSS windows rsion 15.0 software. Statistical differences between groups were performed by one-way analysis of variance (ANOVA) for continuous variables and chisquare test for categorical variables. The baseline characteristics of subjects were expressed as means ± standard deviations for continuous variables. Independent variables tested were age, gender, systolic and diastolic blood pressures. Values of P <0.05 was considered to be statistically significant. RESULTS A total of 55 subjects participated in the study. The subjects were divided into three groups: Normote, Pre-hyperte &. The proportion of pre-hypertension (26, 47.27%) is high when compared to normote and hyperte groups (Table 1). Table 1: Groups and their Mean Age in Years Group Size (N) Mean ±SD F value P Value Normotensi 18 33.39 a ± 6.78 38.9 <0.001 Prehypertensiv 26 48.15 b ± 6 ** 12.54 e nsi 67.45 c ± 7.76 alphabets between groups denotes significance at 5% lel using Duncan Multiple Range Test (DMRT) The prevalence of hypertension among the present study sample is 20%. There is significant proportion between the three groups (p = <0.001**). The mean age of is 67.45 c ± 7.76. The proportion between the three groups (Table 1) with respect to age is highly significant (p = <0.001**). The normality is significantly different with respect to pre-hyperte and hyperte groups at 5%. The difference is also significant between prehyperte and hyperte groups at 5%. Females (42, 76.36%) formed the maximum number of subjects in this study. The number of subjects under the male gender is 13 (23.635%). The orall proportion is significant with respect to gender (p = <0.001**). The mean age ± S.D for males is 49.15±17.69yrs and for females 46.57 ± 15.198yrs (p = 0.447). The prevalence of hypertension is more among the female gender (81.81%) than the male gender (18.18%). The prevalence of pre-hypertension is also more in females (73.07%) when compared to males (26.92%). The study population was categorized into different groups according to their age (Table 2). There are 3 groups: 20 35yrs, 36 50yrs and 51 75yrs. The maximum numbers of participants are in the age group of 51 75yrs (22). Hower, there is a less significant association between sample size and different age groups (p = 0.569). The proportion of gender among different age group was also found to be not significant (p = 0.650). Table 2 : Prevalence of Pre-nsion and nsion among different Age Groups Age Group P Group value in Normoten Pre- nsi years si nsi 20-35 12 4 0 (75.0%) 36-50 6 (35.3%) 51-75 0 (0.0%) Total 18 (32.7%) (25.0%) (64.7%) (50.0%) 26 (47.3%) (.0%) 0 (.0%) (50.0%) (20.0%) 0.000 ** Note: The value within bracket refers to row percentagepre-hypertension is highest in the age group of 36 50yrs and also in the 51 75yrs. All the hypertension subjects are in the group of 51 75yrs. The differences is found to be statistically significant (p<0.001), which indicates that in the present study, age has a strong association with hypertension. There are significant differences between the groups with respect to SBP and DBP (Table 3).
Table 3 : Systolic (SBP) and Diastolic blood (DBP) pressure among the Groups Variab les Groups N Mean ± SD F value P Valu e SBP Normote 18 5.56 a ± DBP Pre Normote Pre 7.374 26 129.62 b ± 4.691 147.36 c ± 8.418 18 76.39 a ± 4.984 26 81.04 b ± 4.686 44.141 38.983 0.00 0** 0.00 0** 91.09 c ± 1.446 alphabets between groups denotes significance at 5% lel using Duncan Multiple Range Test (DMRT) Based on DMRT for the variable systolic blood pressure, the normality is significantly different with respect to pre-hyperte and hyperte groups at 5%. The difference is also significant between prehyperte and hyperte groups. The mean systolic and diastolic blood pressure is found to increase steadily with age, being lowest in the age group of 20 35yrs and highest in the age group of 51 75yrs (Table 4). Table 4 : Systolic (SBP) and Diastolic blood (DBP) pressure among the Age Groups Age N Mean ± SD F P Variabl group value Value es s in Years SBP 20-35 1 7.50 a ± 24.39 0.000 6 7.815 4 ** 36-50 1 124.53 b ± 7 8.133 51-75 2 144.73 c ± 2 7.9 DBP 20-35 1 77.50 a ± 22.71 0.000 6 3.706 2 ** 36-50 1 78.06 a ± 7 6.057 51-75 2 91.14 b ± 2 5.027 alphabets between groups denotes significance at 5% lel using Duncan Multiple Range Test (DMRT) There are significant differences between the age groups with respect to SBP and DBP (p= <0.001**). Based on DMRT for the variable systolic blood pressure, the normality is significantly different with respect to pre-hyperte and hyperte groups at 5%. The difference is also significant between prehyperte and hyperte groups. DMRI for diastolic blood pressure show a significant difference between normote and hyperte but not between pre-hyperte and hyperte. Out of 26 pre-hyperte subjects, 9 are having isolated systolic hypertension (34.61) and all are of female gender. Three (2 females & 1 male) of the prehyperte subjects ha isolated diastolic hypertension. Among hyperte subjects, only two ha isolated diastolic hypertension. The rest ha both systolic and diastolic hypertension. DISCUSSION nsion is considered to be one of the most rampant non-communicable diseases. Previous studies in various geographical locations ha reported the prevalence of hypertension to be about 25% in urban population and 10% in rural population (Kannan and Satyamoorthy, 2009). Indian studies ha shown a high prevalence of hypertension almost similar to those in the USA. The prevalence of hypertension in India is reported as ranging from 10 to 30.9% (Malhotra et al., 1999). Previously a lower prevalence of hypertension was reported from rural Indian populations. Hower there has been a steady increase of prevalence or time in rural population studies as well (Deedwania et al., 2002; Gupta et al., 1997). This made us to undertake the current study to determine the hypertension prevalence in a south Indian rural scenario. Using the JNC VII criteria, we found that the proportion of pre-hypertension (26, 47.27%) is high when compared to normote and hyperte groups. The prevalence of hypertension among the present study sample was 20%. A high prevalence value obtained from our study for pre-hypertension indicates an alarming situation prevailing in the rural populations of Tamil Nadu. From other parts of Tamil Nadu, a higher prevalence of pre-hypertension and hypertension has been reported. Shanthirani et al (2005) reported a 47% prevalence of prehypertension among urban residents of Chennai who were >18 year. In a sury on industrial population, Prabhakaran et al (2005) reported prevalence of prehypertension as 44%. The prevalence rate of hypertension was 25.2% in a rural household community study from Kancheepuram district of Tamil Nadu (Kannan and Satyamoorthy, 2009). Prehypertension is also closely associated with cardiovascular and other related complications. Hence identification of subjects with prehypertension and implementing high risk strategy of
prention of pre-hypertension is important to prent the emerging pandemic of hypertension. In the present study, we obserd female gender (81.81%) more susceptible to hypertension than the male gender (18.18%). The prevalence of prehypertension was also more in females (73.07%) when compared to males (26.92%). Significant results in terms of hypertension prevalence among females were reported by Bharathi et al., (20) and Kokiwar et al., (20). The prevalence rate was higher among females (27.4%) when compared to males (22.6%) (Kannan and Satyamoorthy, 2009). Bharathi et al., (20) also reported pre-hypertension to be more prevalent among females than males. This indicates a changing trend among females and should be probed further to identify the root cause of increased stress. The mean age of hyperte patients was found to be 67.45 ± 7.76 and for pre-hyperte subjects, 48.15 ± 12.54. Kokiwar et al., (20) reported the mean age of hyperte to be 53. ± 12.46. Radhika et al., (2007) reported the mean age to be 44.9 ± 12.9. Mean age of hyperte patients, as reported by the CURES study, was 44.9 ± 12.9 for males. There is an increasing trend of hypertension as age advances (Kannan and Satyamoorthy, 2009). Hower in our study, all the hyperte subjects were in the upper range of the study variable (51 75yrs). In the present study, the systolic and diastolic pressures were found to ha high significance of class variance. In pre-hyperte subjects, female gender and isolated systolic blood pressure was more closely related. Only a few reported to ha isolated diastolic blood pressure among the pre-hyperte and hyperte subjects. The rest had both systolic and diastolic blood pressure. Community based analysis from central India (Kokiwar et al., 20) showed an orall prevalence of isolated systolic hypertension as 4.3% (2.3% males and 5.6% females) while prevalence of isolated diastolic hypertension was low i.e. 0.9% (0.9% males and 1.04% females). In the CURES study, the orall prevalence of isolated systolic hypertension as 6.6% among the study subjects while the orall prevalence of isolated diastolic hypertension was 4.2% (Mohan et al., 2007). The significance of a higher prevalence of systolic blood pressure has to be addressed as systolic blood pressure is more closely related to hypertension and increased cardiovascular risk (Tin et al., 2002). CONCLUSION Orall, our study documented high prevalence of both pre-hypertension and hypertension among the study subjects. The important correlates of hypertension in the present study are age, female gender, systolic and diastolic blood pressures. The high prevalence of hypertension and pre-hypertension in the present study supports the increasing trend in the rural communities of India which are under the epidemiological transition. Hence epidemiological studies to assess the prevalence of pre-hypertension and hypertension are urgently needed in rural areas to ha a base line data about the prevalence of prehypertension and hypertension and its association with the risk factors for cardiovascular and chronic kidney diseases. REFERENCES [1]. Bharati DR, Pal R, Rekha R, Yamuna TV, Kar S and AN Radjou. Ageing in Puducherry, South India: An orview of morbidity profile. J Pharm Bioallied Sci., 20; 3(4): 537-42. [2]. Deedwania P and Gupta R. nsion in South Asians. In: Izzo & Black. Editors. Primer on nsion. American Heart Association 2002. [3]. Deepa M, Pradeepa R, Rema M, Anjana M, Deepa R and Shanthirani S. The Chennai Urban Rural Epidemiology Study (CURES) study design and methodology (urban component) (CURES-I). J Assoc Phys India., 2003; 51: 863 870. [4]. Gupta R, Prakash H, Gupta VP and Gupta KD. Prevalence and determinants of coronary heart disease in a rural population of India. J Clin Epidemiol., 1997; 50: 203-9. [5]. Gupta, R. Trends in hypertension epidemiology in India. J Hum ns., 2004; 18: 73-78. [6]. Kannan and Satyamoorthy. An Epidemiological study of nsion in a rural household community. Sri Ramachandra Journal of Medicine., 2009; 2(2): 9-13. [7]. Kokiwar PR, Gupta Sunil S, Prevalence of hypertension in a rural community of central India. Int J Biol Med Res., 20; 2(4): 950 3. [8]. Madhukumar S, Gaikwad V and Sudeepa D. An Epidemiological study of nsion and its risk factors in rural population of Bangalore rural district. Al Ameen J Med Sci., 2012; 5(3): 264-270. [9]. Malhotra P, Kumari S, Kumar R and Sharma BK. Prevalence and determinants of hypertension in an unindustrialised rural population of North India. J Human ns., 1999; 13: 467-472. [10]. Mohan V, Deepa M, Farooq S, Datta M and Deepa R. Prevalence, Awareness and Control of nsion in Chennai The Chennai urban Rural epidemiology Study (CuReS 52). J Assoc Physician India., 2007; 55: 326-32.
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