Orthostatic Hypotension (OH) in a Population of Hypertensive Patients in the University Hospital Gabriel Touré (UH GT)
Bâ Hamidou Oumar1, Menta Ichaka1, Sangaré Ibrahima1, Sidibé Noumou1, Diall Ilo Bella2, Coulibaly Souleymane2, Daou Adama3, Sogodogo Adama1, Touré Mamadou1, Traoré Aladji1, Djiguiba Youssouf1, Sanogo Kassoum Mamourou1
1University Hospital "Gabriel Touré", Cardiology, Bamako (Mali)
2University Hospital "Point G", Cardiology, Bamako (Mali)
3National support centre for fight against disease, Bamako (Mali)
To cite this article:
Bâ Hamidou Oumar, Menta Ichaka, Sangaré Ibrahima, Sidibé Noumou, Diall Ilo Bella, Coulibaly Souleymane, Daou Adama, Sogodogo Adama, Touré Mamadou, Traoré Aladji, Djiguiba Youssouf, Sanogo Kassoum Mamourou. Orthostatic Hypotension (OH) in a Population of Hypertensive Patients in the University Hospital Gabriel Touré (UH GT). Clinical Medicine Research. Vol. 4, No. 4, 2015, pp. 116-119. doi: 10.11648/j.cmr.20150404.15
Abstract: Objective: This study was intended to determine the prevalence of HO and characteristics of patients who had an OH. Methodology: The study was cross-sectional, conducted in the cardiology department of the UH GT from January to June 2013 in a population of known hypertensive patients aged over 15 years seen as outpatients and who agreed to participate in the study. OH and NonOH were used to name patients with and without OH. OH was looked up to 5 min. The analysis was performed with SPSS software. Results: The overall prevalence of OH was 31.8% Age, SBP, DBP and HR were lower for NonHO patients resp. p = 0.004, <0.0001 <0.0001 and 0.016. The female sex had a low predictive value compared to male (OR 0.594 and p = 0.011). The OR for the occurrence of OH versus the age group > = 60 years were 1.974, 2.616 and 1.692 respectively for ages < 30, 30-44 and 45-59 years (p = 0.004). The OR for the occurrence of OH versus compared to higher education level were 0,411, 0,326 et 0,716 (p=0,049) resp. for unschooled, primary and secondary level. Conclusion: OH is frequent in the hypertensive population with nearly a third of patients. His research must be extended up to 5 minutes.
Keywords: Hypertension, Orthostatic Hypotension, Cardiology, Bamako
HO is defined by a fall of the blood pressure (BP) at the time of the passage in upright posture. The values selected are of 20 mmHg for the systolic blood pressure (SBP) and of 10 mmHg for the diastolic blood pressure (DBP) or an absolute value of SBP less than 80 mmHg in upright position [1-3]. In addition to unpleasant for the patients [4-5], she should be more frequent among hypertensive patients [6-7] and is considered as cardiovascular risk factor (CV RF) [8-10].
Most studies were carried out by seeking up to 3 minutes, moreover little is published about OH in the neighboring countries .
This study thus aimed to determine OH prevalence and characteristics of patients with OH.
It was a cross-sectional study, carried out in the cardiology department of UH GT from January to June 2013.
All hypertensive patients of more than 15 years old, seen in ambulatorium and willing to participate in the study were included (Diagram 1). Approximately 8,9% of the patients were not included either because having made a stroke or because unable to stay upright without support.
The basic BP was obtained from the average of 2 measurements at rest, patient lying on his, then 4 measurements were successively carried out immediately after the upstanding, at 1,3 and 5 minutes in standing position. Measurements were carried out with an automatic BP-device of Hartmann model "Tensoval Comfort".
The definition retained for OH was the fall of SBP of more than 20 mmHg and/or of DBP of more than 10 mmHg.
For the analysis 2 groups were formed: those with OH and those without resp. called OH and NonOH.
Data were collected on a formulary then inputted in a Microsoft Access 2007 Database designed for this purpose.
The analysis was carried out with software SPSS v 12 after initial treatment with Microsoft Excel 2007.
After a descriptive analysis of the sample, the cross tables made it possible to evaluate the prevalence of HO according to several variables and a logistic regression carried out for the categorical variables.
For the continuous variables, a variance analysis with post-hoc test was carried out to study associations between occurrence of the OH and various variables of the sample.
The study involved 597 patients (374 of female sex, sex-ratio Men:Women=0.59), with a mean age of 54,15 ± 13,542 years.
The overall prevalence of OH was 31,8% (Diagram 2).
Significant differences were found for age (56,46 for OH against 53,08 for NonOH with p=0,004), for SBP (158,96 for OH versus 144,31 for NonOH), DBP (97,60 for OH and 90,00 for the NonOH with p <0,0001) and HR of 86,52/min for the group OH against 83,29/min for the NonOH group with p=0,016. (Table I).
|Variables||OH (N= 190) Mean ± SD*||NonOH (N= 407) Mean ± SD*||p|
|Age||56,46 ± 13,422||53,08 ± 13,478||0,004|
|Weight||67,94 ± 13,626||69,81 ± 14,331||0,133|
|Height||164,34 ± 7,413||165,57 ± 7,553||0,062|
|BMI**||25,18 ± 4,924||25,48 ± 5,113||0,499|
|Baseline SBP||158,96 ± 28,273||144,31 ± 24,623||<0,0001|
|Baseline DBP||97,60 ± 16,425||90,00 ± 14,759||< 0,0001|
|Baseline HR||86,52 ± 15,475||83,29 ± 15,058||0,016|
*SD: standard deviation, ** Body Mass Index
Socio-demographic characteristics significantly different were sex (70,5% of OH for the female sex against 29,5% for the male sex with p=0,007), the age (from 3,7% of OH in age under 30 years to 46,3% for patients older than 60 years with p =0,007) and the educational level (72,1% of OH among unschooled patients to 2,1% in those in higher level with p=0003) (Table II).
|Variables||OH N (%)||NonOH N (%)||p|
|Sex||Female||134 (70,5)||240 (59,0)||0,007|
|Masculine||56 (29,5)||167 (41,0)|
|Age range (years)||< 30||7 (03,7)||18 (04,4)||0,007|
|30-44||25 (13,2)||86 (21,1)|
|45-59||70 (36,8)||171 (42,0)|
|>= 60 years||88 (46,3)||132 (32,4)|
|Level of schooling||None||137 (72,1)||247 (60,7)||0,003|
|Primary||28 (14,7)||53 (13,0)|
|Secondary||21 (11,1)||80 (19,7)|
|Higher||4 (02,1)||27 (06,6)|
|Diabetes||Yes||19 (10,0)||34 (08,4)||0,510|
|No||171 (90,0)||373 (91,6)|
|Tobacco Smoking||Yes||33 (17,4)||80 (19,7)||0,506|
|No||157 (82,6)||327 (80,3)|
|Body Mass Index||Underweight||14 (07,4)||18 (04,4)||0,482|
|Normal weight||83 (43,7)||192 (47,2)|
|Overweight||63 (33,2)||132 (32,4)|
|Obesity||30 (15,8)||65 (16,0)|
We didn’t find significant difference in the crosstab number of medicaments and occurrence of orthostatic hypotension (Table III)
|Number of medicaments||Total sample N (%)||OH N (%)||NonOH N (%)||p|
|1||121||35 (28,9)||86 (71,1)||0,660|
|2||153||41 ( 26,8)||112 (73,2)|
|3||137||43 (31,4)||94 ( 68,6)|
|4||6||3 (50,0)||3 (50,0)|
|5||1||0 (0,0)||1 (100)|
The logistic regression on significantly different variables in cross-tables allowed to find female sex (OR 0,594 and p=0,011).
Odd-ratios for the occurrence of OH versus the age group > = 60 years were 1.974, 2.616 and 1.692 respectively for ages < 30, 30-44 and 45-59 years (p = 0.004).
The OR for the occurrence of OH versus compared to higher education level were 0,411, 0,326 et 0,716 (p=0,049) resp. for unschooled, primary and secondary level (Table IV)
|Sex||Female vs male||0,594||[0,398-0,888]||0,011|
|Age range||vs >= 60||0,004|
|Level of schooling||vs Higher||0,049|
Our study was conducted in a large sample of 15 years and older hypertensive, including males and females with various educational levels. It thus made it possible to confirm certain data of the literature in particular:
• an overall prevalence of OH of 31,8%, lower than the 34,2 and 55% resp. of Weiss  and Poon . It in particular higher than the 20,5% is obtained by Baragou , difference who could be explained by the research of OH in our study up to 5 minutes. This variability of the prevalence of OH depends on several factors and conditions [11-18]
• our data suggested that more the blood pressure and the basic heart rate are high, more frequently occurred OH, this explainable on the one hand by the need for a greater number of drugs to lower BP. However even we did not find it in this study, many studies had highlighted a link between the number of drugs and the occurrence of OH [1,12]
In the majority of the studies, a male prevalence is found, which was not the case in our study, as in that of Fedorowski  which is a study on the general population.
We didn’t find in the literature data on the educational level, which the more high the lower the occurrence of OH.
In this study we could not evaluate OH evolution in the time, which should be the subject of later studies.
OH is frequent among hypertensive population with nearly a third of the patients. The advanced age, the female sex, low education level, high baseline BP and HR are associated with a greater frequency of OH occurrence. The research of OH should be extended to 5 min in this group of patients