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The Epidemiology of Elevated Blood Pressure As an Estimate For Journal of Human Hypertension (1999) 13, 399–404 1999 Stockton Press. All rights reserved 0950-9240/99 $12.00 http://www.stockton-press.co.uk/jhh ORIGINAL ARTICLE The epidemiology of elevated blood pressure as an estimate for hypertension in Aydın, Turkey · HM So¨nmez1, O Bas¸ak2, C Camcı1, R Baltacı3,HS¸ Karazeybek4, F Yazgan4,IErtin5 and S¸C¸ C¸elik6 Departments of 1Internal Medicine and 2Family Practice, School of Medicine, 3Students Health Centre, Adnan Menderes University, Aydın; 4Social Insurance Hospital, Aydın; 5Kuyucak Health Centre, Aydın; 6Gu¨ llu¨ bahc¸e Health Centre, Aydın, Turkey Background: Hypertension is an important public health (for BP у140/90 mm Hg or on treatment). Hypertension problem, with some variability of its epidemiological prevalence increased progressively with age, from 9% properties in different populations. in 18- to 29-year-olds to 70.6% in those 70–79 years of Objectives: The purpose of this study was to estimate age. Women had a significantly higher prevalence than the prevalence of hypertension and to determine the men (34.1% vs 26.0% respectively). Overall, 57.9% of hypertension awareness, treatment and control rates in hypertensive individuals were aware that they had high Aydın, a Turkish province. BP, and 82.1% of aware hypertensives were being Methods: Of 1600 coincidentally selected people aged treated with antihypertensive medications, but only over 18 years in Aydın, 1480 (92.5%) had their blood 19.8% of treated hypertensives were under control pressure (BP) measured and answered a standard ques- (systolic pressure Ͻ140 mm Hg and diastolic pressure tionnaire in 1995. Ͻ90 mm Hg). In addition, housewives, unemployed, and Results: Estimates of the prevalence of hypertension the less educated individuals had greater mean systolic and its control were computed using two different cri- and diastolic BP. teria to define hypertension: BP у140/90 mm Hg or on Conclusions: Our results indicate that hypertension is treatment and BP у160/95 mm Hg or on treatment. Over- highly prevalent in Aydın, Turkey, and the detection and all, the estimated prevalence of hypertension was 29.6% control of hypertension is unsatisfactory. Keywords: hypertension; prevalence; detection; awareness; control; Turkey Introduction The Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure Hypertension (HT) is an important public health (JNC V) have suggested a new classification of adult problem. High blood pressure (BP) is one of the BP and have divided high BP into four stages that major risk factors for cardiovascular disease and the convey more efficiently the major impact of HT on most important risk factor for cerebrovascular dis- 1,2 the risk of cardiovascular disease. It has been eases. The data from various epidemiological defined that even high-normal BP, as well as high studies about HT have shown that 15–25% of the BP stage 1 (previously termed mild) results in target- population have high BP, and that detection, treat- organ damage. People with high-normal BP are at ment and control of HT decrease the mortality and increased risk of experiencing cardiovascular 3–7 morbidity from stroke and coronary heart disease. events, compared to otherwise similar persons with According to the estimates derived from the lower blood pressures.1,10 However, most hyperten- National Health and Nutrition Examination Surveys sives are unaware of their condition, aware but III, there are 50 million people with elevated BP or untreated, or treated inadequately. taking antihypertensive medication in the USA The epidemiological properties of HT show some resulting in a loss of 2 million years of human life a 3,6,11–13 1,8 variability in different populations. In year or 500 000 productive years per annum. The addition, each country has different socio-economic, mortality from stroke has decreased approximately cultural, and health care capabilities. However, few 1% annually possibly as a result of improvement in national or regional data have been published on the taking antihypertensive treatment and controlling 14–18 9 epidemiology of HT in Turkey. HT during the last two decades. With the purpose of identifying individuals with elevated BP previously detected or not and those Correspondence: Yrd. Doc¸. Dr Okay Bas¸ak, Adnan Menderes inadequately treated· or uncontrolled,· we carried out Universitesi, Tıp Faku¨ ltesi Aile Hekimlig˘i Anabilim Dalı 09100, the AYDIN HI·PERTANSIYON ARAS¸TIRMASI sur- Aydın, Turkey vey (AYDINHIP) in our university region, Aydın, Received 13 January 1999; accepted 3 February 1999 Turkey, in 1995. The epidemiology of hypertension in Aydın, Turkey HM So¨nmez et al 400 Subjects and methods Blood pressure measurement After the subjects had answered the questions in the Study design questionnaire and rested for 5 min, two sitting BP measurements were taken in the right arm with a This was a cross-sectional survey. Data collection pretested aneroid sphygmomanometer approxi- was obtained by structured interviews using preco- mately 2 min apart. The accuracy of eight aneroid ded questionnaires administered by trained inter- sphygmomanometers used in the screening were viewers in the subjects’ homes and at worksites. checked at different pressure levels by connecting Interviewers were trained according to a standard- them with a metal T-connector to the tubing of a ised protocol for the measurement of BP. Standard- standardised mercury column manometer.21,22 The ised questionnaires were administered prior to the average of two readings was used to determine the measurement of BP. The questionnaire included BP level. The cuff size was 23 × 12.5 cm. The sys- questions on demographic information, and on the tolic (SBP) and diastolic BP (DBP) readings were subjects’ knowledge of BP and treatment status as defined as corresponding to the first of two consecu- well as questions on their health status. tive Korotkof sounds and the disappearance of A kind of systematic sampling procedure was sound, respectively. BP measurements were taken used in selecting the study population. Screening on one occasion only and recorded to the nearest 2 was conducted in the city centre, and in two towns mm Hg. BP measurement procedures recommended and two villages from both the west and east sides by WHO/ISH were followed.4 of the city centre, covering eight geographic areas. The sampling was based on household and worksite selection. The households and worksites on either Statistics the right side or the left side only of a street were All recorded data was transferred to a PC media and visited. Each investigator visited 200 persons who analysed using the Statistical Package for Social met the criteria of inclusion and invited them to par- Sciences (SPSS) software.23 Frequency, cross-table, ticipate in the study. Screening was performed Levene’s test, Student’s t-test, Pearson’s bivariate between March and May (in the Spring season) and correlation test, analysis of variance (ANOVA), between 8 and 11 am every investigation day. We analysis of covariance (ANCOVA) and Tukey-HSD did not include in the study those who were not test were used in statistical assessment with signifi- resident of the region, who had a mental disorder, cance level of 0.05. severe obesity or a chronic metabolic illness such as chronic renal failure, hypothyroidism, and hyper- thyroidism and who were under 18 years old. Results Decision to exclude was based on the history taking General findings from the individuals visited and on the observations of the interviewers. Subjects were assessed to be sev- Of the 1466 subjects included in the study, 44.5% erely obese if they were unable to participate in were women and 55.5% men. Thirty-four percent of daily activities due to obesity. the people screened had an educational level higher than primary school and 58% were non-smokers. Thirty-one percent of the study subjects were house- wives, 12% self-employed, 20% farmers, 18% offi- Population cers (not army officers), 11% workers and 8% unem- ployed. This survey was carried out in Aydın (a south-west- Two hundred and eighty-four participants ern province in Turkey) with about 540 000 inhabi- reported having HT previously. But, 32 of these tants over 18 years of age. We visited 1600 persons individuals had BP within the normal range (50 having study criteria of whom 120 persons refused individuals for 160/95 mm Hg cut-off point), an invitation to participate in the study. Non- although they did not use antihypertensive medi- response rate was 7.5%. Fourteen participants were cation. Therefore, these people have not been excluded from the study at the stage of analysing included in the estimate for HT. Among the subjects data obtained because of the reasons mentioned reporting a diagnosis of HT, 51% were practising above. Therefore, we screened 1480 subjects and salt restriction. While 77 previous hypertensives recruited 1466 of them (813 males, 653 females). A (27%) were not on antihypertensive medication and total of 970 participants (66%) were from urban 84 previous hypertensives (30%) were taking drug centres (with inhabitants above 10 000) and 496 treatment inconsistently, only 123 previous hyper- (34%) from the rural areas. The average age was tensives (43%) reported taking regular antihyperten- 47.6 ± 15 years and median 44 years (46.2 ± 15.2 and sive medication. 45 for men, and 44.9 ± 17 and 43 for women). Sixty- three percent of participants were aged 18–50 years. Blood pressure findings The histogram of age was slightly depressed from right to left (Kurtosis: −0.78 ± 0.1 and Skewness: The prevalence of HT was estimated using the level 0.37 ± 0.06), reflecting the predominance of young of 140/90 mm Hg, as recommended by the JNC V. In people in Turkey. About half of the population of addition, it was assessed according to criteria of the Turkey are between 15 and 44 years old, and the WHO/ISH (BP у160/95 mm Hg).
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