AH is a major public health problem because of its high prevalence and strong positive association with CVD and stroke and it is the main modifiable risk factor of CVD . Proportions of hypertensive patients with CVD are very high, but all preventive measures, awareness, treatment and control need to be significantly improved to diminish the prevalence of AH. The main purpose of this study was to determine time trend in the prevalence of AH in 1983–2002, as well as to assess awareness, treatment, and control of this condition among hypertensive men and women aged 45–64 years, and to examine the risk of AH and mortality among middle-aged Lithuanian population. In this survey, the prevalence of AH ranged from 52.1% to 58.7% among men, and from 61.0% to 51.0% - among women in 1983–1984 to 2001–2002, respectively, using 140/90 mmHg as a threshold.
Analysis of data from the 35 countries (systematically review over the past 6 years) show that the prevalence of AH among men and women was lower in developing than in developed countries (among men 32.3% vs. 40.8%; among women 30.5% and 33.0%) . Data from the 24 geographically defined populations of the WHO MONICA Project show, that the age-adjusted prevalence of AH decreased in most and increased in only a few populations: the highest prevalence was found in Turku, Finland, where 60% of men were hypertensive; among women, the highest prevalence of AH was found in Novosibirsk, Russia (54%); the lowest prevalence was found in Catalonia, Spain, among both men (19%) and women (20%) . Data from 6 European countries and national surveys in United States and Canada, show that the prevalence of AH as standard threshold (ie, BP ≥140/90 mmHg or treatment with antihypertensive medication) was highest in Germany (55%), followed by Finland (49%), Spain (47%), England (42%), Sweden (38%), and Italy (38%) . Also the data informed that the prevalence of AH for the European average was 44.2% compared with 27.6% in North America and the prevalence in the United States and Canada were half of the rate in Germany (28% and 27%, respectively) . In France AH (high BP was defined as BP at least 140/90 mmHg and/or taking antihypertensive drugs) is frequent also, particularly in the age group 55–74 years: the prevalence of high BP was greater in men (47%) than in women (35%) and antihypertensive treatment concerned 80% of the hypertensive individuals with most often a combination therapy. Control rates concerned only 38% of women and 22% of men and decreased with age . Data from the National Health and Nutrition Examination Survey (NHANES) 1988–1994 and 1999–2008 show that BP was controlled in an estimated 50.1% of all patients with AH in NHANES 2007–2008, with most of the improvement since 1988 occurring after 1999–2000 . Data from SEPHAR Study (Romania) show that the prevalence of AH was significantly higher in men (50.2%) than in women (41.1%)  AH awareness attended significantly lower in men (34.6%) than in women (52.8%); the rate of AH control was 19.9%, with no significant differences between gender . Analysis of data from 35 countries (systematically review over the past 6 years) showed that the mean awareness, treatment and control of AH between developed and developing countries men did not differ (40.6, 29.2 and 9.8%, respectively, in developing countries and 49.2, 29.1 and 10.8%, respectively, in developed countries); among women, the mean awareness, treatment and control of AH were lower in developing than in developed countries (52.7, 40.5, and 16.2%, respectively, in developing countries and 61.7, 40.6 and 17.3%, respectively, in developed countries) . Data from Czech six independent cross-sectional population surveys (the total number of participants was 13,972) show, that since 1985 awareness of AH in Czech population increased in both sexes (men, from 41.4 to 68.4%; women, from 58.9 to 71.4%; both P < 0.001) as did the number of individuals on antihypertensive medication (men, from 21.1 to 58.2%, women: from 38.9 to 58.9%; both P < 0.001). Control of hypertension improved significantly (from 3.9 to 24.6%) over the same period .
In our survey as in many other studies [10, 14–16, 19–23] AH awareness and control were higher in women than in men, but the percentages of control indicate that women had a possibly better perception of hypertension-associated risks. In addition, some positive improvements in AH awareness, treatment and control were observed. According to our results, in men the general rate of AH awareness increased from 45.0 to 64.4% (p for trend 0.03) as well as in woman from 47.7 to 72.3% (p for trend 0.01). In 1983-1984 the proportion of treated hypertensive subjects was only 55.4% in women and 65.6% in men. In 2001-2002 the rate of treated AH increased and again was in favor of women (86.2%) in comparison with men (68.3%). In men AH control was very low and did not significantly change during 19 year period whereas in women increased from 3.5 to 16.6%.
A large number of observational studies have demonstrated that CVD morbidity and mortality bear a continuous relationship with both systolic and diastolic BP . The relationship has been reported to be less steep for coronary events than for stroke which has thus been labeled as the most important AH related complication. In our longitudinal study of four cohorts the dose–response association between BP level and all-cause, CVD, CHD and stroke-mortality risk was observed.
Data from observational study of 12,677 patients, (treated with antihypertensive drugs, without previous congestive heart failure) aged 30–75 years in Sweden (followed for 5 years) show that hazard ratios for CHD and stroke per 10-mmHg increase in updated mean systolic BP in all participants, adjusting for clinical characteristics and traditional risk factors, were 1.08 (1.04–1.13) and 1.20 (1.13–1.27), P < 0.001 . In contrary, the data analysis of 33,372 Japanese men and women aged 40–69 years, free of prior diagnosis of cancer and CVD, stroke incidence show that the stoke incidence was highest for mild AH, and lower for moderate to severe AH in both sexes .
Data from the Third National Health and Nutrition Examination Survey and mortality follow-up through 2000 show that CVD mortality risk for uncontrolled AH was 1.74 (95% CI 1.28–2.49, p = 0.007) and for controlled AH 1.15 (95% CI 0.79–1.80, p = 0.53) . BP at a high range of prehypertension (130–139/84–89 mmHg) was associated with increased risk of CVD mortality (hazard ratio 1.41, p < 0.05) relative to BP less than 120/80 mmHg . Epidemiologic data have revealed that the BP control is achieved in only a small percentage of hypertensive patients [10, 14–16]. In central European countries, BP control is only 20% to 25% .
Data from the Minnesota Heart Survey study show that population mortality trends for stroke paralleled those for AH control and women had lower rates of stroke mortality than did men throughout the period . Data from the Minnesota Heart Survey study show that proportions of hypertensive patients in the aware, treated, and/or controlled categories leveled in the 1980s and 1990s, but improved substantially from 1995 to 1997 and 2000 to 2002 with BP controlled at the less than 140 and/or 90 mmHg criteria in 44% of the men and 55% of the women; and population mortality trends for stroke paralleled those for AH control. Data from the HAHS (Harvard Alumni Health Study) study show that higher BP in early adulthood was associated with elevated risk of all-cause mortality, CVD, and CHD, but not stroke, several decades later . Since the major part of the risk of mortality was due to AH, a population strategy to promote awareness and control of hypertension should be encouraged.
It is important to be aware of several limitations of our results. The present study did not examine a national sample, but rather included only a random sample of 45–64 year-old of urban population. A future study is needed to examine younger and the oldest samples. The analysis of the whole cohort was limited to a single examination that individuals were classified as hypertensive based on measurements that were obtained on a single occasion, although averaged over two readings. During the follow-up, hypertensive subjects without treatment at inclusion may have been treated later, especially since treatment of AH was not getting persistent. Only 12.6% of men and 16.6% of women demonstrated control of AH. Poor control of AH may be attributed to the lack of procedures that increase the level of compliance and medication adherence.