Hypertension is one of the major risk factors for morbidity and mortality in cardiovascular diseases, but etiology and pathology for hypertension are not completely clarified. This open-label study focuses on the examination of impacts of an antihypertensive therapy of three to six months on the blood pressure parameters of young adults.
After intense screening, medical consultation and personal consent, 18 students in total could be included in the study. All of them had high systolic blood pressure in repeated long-term blood pressure measurements. The participants of the intervention group (n=9) took a lower dosage of antihypertensive medication over a limited period of three or six months. After discontinuing medication, the blood pressure was observed three further months. The participants of the control group (n=9) received no medication. The initial measurement was followed by further long-term blood pressure measurements at set control points.
The low dosage of taken medication led to a significant reduction of the systolic blood pressure, the mean arterial pressure and the heart rate in the intervention group. After discontinuing the antihypertensive medication, the blood pressure increased moderately but not significantly. Despite the low increase of the blood pressure parameters after discontinuing medication, the systolic blood pressure and the pulse pressure were, as compared to the base level, lower at the time of the final measurement. The blood pressure parameters in the reference group showed no significant change and remained on a stable level over the entire period.
Systolic blood pressure and pulse pressure may decrease as an effect of a preceding pharmaceutical therapy in young adults with high systolic blood pressure. Nevertheless, further investigations should follow due to the relatively small study population.
hypertension, therapy, young adult
According to the German Statistical Office, cardiovascular diseases are the most common cause of death (41.1 %) in Germany
In the scope of a long-term study, blood pressure parameters of 240 students of the University of Leipzig were determined by taking the blood pressure at rest and by 24h-blood pressure monitoring. The long-term blood pressure measurements were made due to the fact that blood pressure is a variable and repeated measurements under everyday conditions probably give detailed information about the cardiovascular risk. After intense screening, remeasurements (n = 36), medical consultation and personal consent, 18 male participants in total were assigned to either intervention (n = 9) or control group (n = 9). The participants of both groups were between the age of 20 and 28 years. In comparison to the limits for long-term blood pressure monitoring set by the European Society of Hypertension, all of the participants had elevated systolic blood pressure values
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23.44 ± 2.7 | 22.78 ± 1.99 |
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179.00 ± 0.07 | 181.00 ± 0.06 |
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77.21 ± 9.03 | 79.01 ± 10.74 |
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23.99 ± 1.77 | 24.15 ± 2.15 |
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141.26 ± 8.02 | 137.32 ± 2.74 |
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74.55 ± 4.50 | 73.90 ± 3.56 |
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67.52 ± 7.63 | 66.54 ± 5.90 |
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9.5 ± 6.6 | 7.8 ± 3.5 |
* average value and standard deviation in the study population
The sample period began in May 2009 and lasted until February 2012. In the scope of the study, the participants of the intervention group underwent six long-term blood pressure monitorings and the participants of the control group four. The time pattern in
All statistical evaluations were made with the programs SPSS 15.0 (SPSS Inc., Illinois, USA) and GraphPad Prism 6.0 (GraphPad Software Inc., California, USA). Due to the distribution requirements that could not be met and the small sample size, nonparametric tests were used. The comparison of the parameters with regard to their central tendency between the single measurements was made with the help of Friedman’s rank variance analysis. For this reason, the critical difference according to Schaich & Hamerle (1984; according to Bortz et al., 2000) was determined by using the Χr²-value of the Friedman test
In the intervention group, the low dosage of taken medication (β-blockers, ACE inhibitors) led to a significant reduction of the systolic blood pressure, the mean arterial pressure and the heart rate. No significant increase of these parameters could be determined after discontinuing antihypertensive medication. Despite the slight increase of the blood pressure parameters after discontinuing medication, the systolic blood pressure and the pulse pressure were, as compared to the base level, reduced by 6.59 (±5.02) mmHg or 6.43 (±4.58) mmHg at the final measurement (see
The Friedman test shows significant or even highly significant differences in the central tendency of the following measurements:
measurement | 1 |
2 |
3 |
4 |
average_RRsys [mmHg] | 141.26 ± 8.02 | 130.16 ± 4.17 | 133.81 ± 6.42 | 134.67 ± 5.02 |
average_RRdia [mmHg] | 74.55 ± 4.50 | 69.86 ± 5.26 | 72.16 ± 3.10 | 74.39 ± 6.99 |
Average_HR |
67.52 ± 7.63 | 61.61 ± 7.01 | 62.76 ± 9.31 | 65.65 ± 6.02 |
Average_MAP [mmHg] | 96.79 ± 3.43 | 89.96 ± 4.54 | 92.71 ± 3.61 | 94.49 ± 6.03 |
average_PP [mmHg] | 66.71 ± 10.21 | 60.30 ± 4.04 | 61.65 ± 5.67 | 60.28 ± 4.58 |
daily_average_RRsys [mmHg] | 146.61 ± 9.24 | 13.80 ± 5.60 | 140.30 ± 7.74 | 141.09 ± 5.41 |
night_average_RRsys [mmHg] | 122.19 ± 6.04 | 114.07 ± 4.19 | 116.33 ± 6.13 | 119.71 ± 7.21 |
daily_average_RRdia [mmHg] | 77.34 ± 4.82 | 72.59 ± 5.72 | 76.10 ± 3.67 | 77.93 ± 6.63 |
night_average_RRdia [mmHg] | 65.24 ± 6.83 | 62.27 ± 7.10 | 62.02 ± 4.77 | 65.67 ± 7.76 |
daily_average_HR [min-1] | 71.58 ± 9.12 | 63.98 ± 7.78 | 66.93 ± 10.62 | 68.98 ± 6.84 |
night_average_HR [min-1] | 54.64 ± 4.33 | 54.53 ± 7.73 | 51.72 ± 6.56 | 56.88 ± 4.63 |
daily_average_MAP [mmHg] | 100.43 ± 3.62 | 93.66 ± 5.29 | 97.54 ± 4.45 | 98.81 ± 5.76 |
night_average_MAP [mmHg] | 84.23 ± 5.48 | 79.53 ± 5.12 | 80.67 ± 5.06 | 83.69 ± 7.14 |
These results are confirmed by the comparison of the empirically determined Χ²-values with the determined critical Χ²-values (=7.81). The subsequent detailed result interpretation, using the post-hoc analysis with two-sided interrogation for the calculation of the critical difference (=1.93), reveals that the systolic blood pressure values (average, daily and night average), the heart rate (daily average) and the mean arterial pressure (average) differ significantly from each other between the first and second measurement. All other differences indicated no significant change.
measurement | 1 |
2 |
4 |
average_RRsys [mmHg] | 137.32 ± 2.74 | 137.53 ± 5.30 | 136.83 ± 8.23 |
average_RRdia [mmHg] | 73.90 ± 3.56 | 75.20 ± 5.62 | 75.00 ± 6.47 |
average_HR |
66.54 ± 5.90 | 67.61 ± 7.40 | 64.86 ± 3.05 |
average_MAP [mmHg] | 95.04 ± 2.68 | 95.98 ± 5.28 | 95.61 ± 6.80 |
average_PP [mmHg] | 63.42 ± 4.13 | 62.34 ± 3.44 | 61.82 ± 4.37 |
daily_average_RRsys [mmHg] | 143.86 ± 4.77 | 144.24 ± 8.10 | 143.42 ± 9.97 |
night_average_RRsys [mmHg] | 118.67 ± 5.67 | 116.09 ± 6.73 | 117.50 ± 5.67 |
daily average_RRdia [mmHg] | 77.90 ± 4.21 | 79.23 ± 7.53 | 78.95 ± 7.15 |
night_average_RRdia [mmHg] | 62.63 ± 4.57 | 62.54 ± 5.08 | 63.34 ± 5.61 |
daily_average_HR [min-1] | 71.63 ± 6.37 | 72.71 ± 8.59 | 69.53 ± 4.05 |
night_average_HR [min-1] | 52.59 ± 6.37 | 51.46 ± 6.71 | 51.26 ± 9.06 |
daily_average_MAP [mmHg] | 99.89 ± 3.63 | 100.90 ± 7.49 | 100.44 ± 7.80 |
night_average_MAP [mmHg] | 81.31 ± 4.40 | 80.39 ± 5.41 | 81.39 ± 5.08 |
The course of the blood pressure parameters and the heart rate of the control group are shown in table 3. It can be noted that all measured variables move on a constant level during the documented period. The analysis of the average values with regard to their central tendency (Friedman test) revealed no significant change.
It can be noted that statistically, there is no significant difference between the blood pressure parameters and the heart rate of both groups at the time of the first measurement (initial measurement) and third measurement (three months after the end of therapy or even six or nine months after the initial measurement). As opposed to this, the average and daily average values of the systolic and diastolic blood pressure, the mean arterial pressure and the heart rate of the intervention group, which were determined with the help of the long-term blood pressure monitoring, can be significantly isolated from the control group by the lowering of the values at the time of medication intake.
The results revealed that the therapy group benefits from the intervention because by comparison, there could no significant or tendential changes of the parameters be documented in the untreated control group. So it can be assumed that the mediated blood pressure reduction during the time of the intake of medication enables the organism, but especially the short- and middle-term blood pressure regulation mechanisms, to sensitization and adaptation processes. On the basis of the collected data however, it is not possible to make any statement about the specific structures and physiological processes responsible for the lowering.
The comparison with other therapy studies is difficult because most examinations in hypertension research are linked to endpoints (cardiovascular events or death). High-risk patients are frequently chosen for those studies to reinforce the statistical significance. In contrast, young patients and patients with uncomplicated blood pressure or with a moderate cardiovascular risk are rarely represented. In a study from 1993, Materson et al. compared the effect of six antihypertensive medications with a placebo tested on men with diastolic blood pressure values between 95 and 109 mmHg
The comparison of the effect of the performed intervention with other therapies that orient more on a change of lifestyle, records that the tendential lowering of the systolic blood pressure, which was achieved in the investigation, is similar to the effects of relaxation procedures and biofeedback therapy
In general, epidemiologic data of hypertension investigation
This was one of the first investigations of this kind. Young patients and patients with uncomplicated hypertension are a rather unusual research topic in the investigation of hypertension. This is the reason why there are a number of open questions and starting points. It is necessary to confirm the present results by future studies with a bigger sample size and to support them statistically more reliable. Furthermore, it is necessary to check the effects regarding different influential variables such as age, family anamnesis, period of therapy, size of the initial blood pressure and used antihypertensive medication.
Additionally, the observation period after discontinuing medication could be expanded to see how the blood pressure develops over a long period. The therapy could also be performed together with drug-free treatments (weight reduction) to check if there are additive effects regarding the reduction of the blood pressure.