The incidence of hypertension among Africans- Americans is high. Although many researchers report that genetics play an imperative role in the occurrence of hypertension among Africans-Americans, the prevalence of high blood pressure is low in Africans. Cooper et al., (1999) conducted studies to explore the reasons behind the high incidence of hypertension in Africans-Americans.
They conducted three studies before concluding that genetics and environmental factors are imperative for the occurrence of hypertension in Africans and Americans. This paper will analyze the three studies about the prevalence of hypertension.
The incidence of hypertension among Africans- Americans is high. Although many researchers report that genetics play an imperative role in the occurrence of hypertension among Africans-Americans, the prevalence of high blood pressure is low in Africans. Therefore, there is a possibility that, a positive correlation exist between genetic makeup of an individual, environment and occurrence of hypertension.
Cooper et al., (1999) conducted a study to explore the reasons behind the high incidence of hypertension in Africans-Americans. They used a variety of research designs before making conclusions. The hypothesis of the studies was; hypertension occurs because of the interaction between external factors, internal physiology and genes (Cooper et al., 1999). External factors include things like stress and diet while internal factor is the physiology of blood pressure.
Cooper et al., (1999) conducted a retrospective study in some parts of the world to determine the cause of hypertension. The study population was rural communities in Nigeria, Cameroon, Zimbabwe, St. Lucia, Barbados, Jamaica and the United States. They reviewed medical records about mortality as well as expectancy rate and interviewed patients with hypertension.
They found out that the prevalence of hypertension was low in Nigeria and high in Barbados. Besides, the risk of hypertension was overweight, inadequate exercise and poor diet. On the other hand, there was no relationship between hypertension, increase in age and atherosclerosis.
In another study, Cooper et al., (1999) examined how environmental factors interact with a person’s physiological functions to produce hypertension. The assumption was that the ability of a person’s body to process and regulate salt would determine if that person is susceptible to hypertension.
The study was experimental and Cooper et al., (1999) measured the levels of angiotensinogen in blood. They found out that the higher the levels of angiotensinogen in blood, the higher the blood pressure and vice versa. Additionally, environmental factors like a diet rich in fats triggers the production of angiotensinogen. On the other hand, some people have genes that trigger the production of angiotensinogen and as a result, they have high blood pressure regardless of environmental factors.
Cooper et al., (1999) reviewed published literature to investigate the relationship between high blood pressure and slavery. They found out that hypertension was prevalent among Africans who had migrated to Europe than among the whites. Cooper et al., (1999) concluded that, genes and race are imperative for the development of hypertension in a person.
The Critique of Methodology
Cooper et al., (1999) conducted a retrospective study design by reviewing medical records. The advantage of this method is that the results are valid because it is supported by written documents. On the other hand, some communities did not have a clear record of mortality and morbidity and this interfered with validity and reliability of the findings. Secondly, the researchers interviewed people with hypertension.
This kind of data collection is usually biased because an interviewee can lie about the kind of diet that he takes and the activities that he does. Secondly, the selected sample was not a true representative of Africa and America. This is because most of the countries that were involved in the study were in Africa yet hypertension is prevalent among Africans and Americans.
In the second study, Cooper et al., (1999) used the experimental design. The strength of this method is that it is reliable and researchers can repeat in different parts of the world. Therefore, different researchers can use this method to investigate more about the issue of the prevalence of hypertension in Africans and Americans.
On the contrary, people may have a hidden factor that can interfere with the levels of angiotensinogen in the body. For instance, obesity, high salt diet and genes can trigger the production of angiotensinogen yet some researcher may not consider it. Additionally, the researcher can easily manipulate the reagents, hence, interfering with the findings. As a result, the findings will be erroneous. Secondly, the selected subjects were few and thus, the findings of the study cannot be generalized.
In the final study, Cooper et al., (1999) reviewed published literature. This kind of research methodology is not reliable because publishers can alter the results. For instance, a publisher can change the data that the researcher has given him to publish because of personal interests. Therefore, we cannot fully rely on the fact that there is a correlation between slavery and the prevalence of hypertension because the information was from secondary sources.
The Critique of Results
In the first study, Cooper et al., (1999) found that hypertension was prevalent in United States. They presented the information in a bar graph. Bar graph is a good presentation of information because it is easy to understand. For example, from the bar graph of incidence of hypertension, one can see that blood pressure is uncommon in African countries. Additionally, they presented the information about the relationship between body mass index and hypertension on a graph.
This makes it easier for someone to understand that hypertension is common in the United States because many people have a body mass index that is more than twenty five. The limitation of the graph method of data presentation is that the researcher cannot present the findings in details. For example, Cooper et al., (1999) did not present information about exercise, diet, and increase in age and cholesterol, yet they play a significant role in development of hypertension.
In the second research about how environmental factors interact with a person’s physiological functions to produce hypertension, Cooper et al., (1999) presented the findings in forms of diagrams and a graph. They found out that the higher the levels of angiotensinogen in blood, the higher the blood pressure.
The advantage of a diagram is that it attracts the attention of the reader. Therefore, many people are empowered with information about the cause of rising levels of angiotensinogen in the blood and its role in alleviating the blood pressure. The graph about the relationship between genes responsible for hypertension and its incidence portray a clear picture of the puzzle of hypertension. This is because in Nigeria where many people have the genes, the prevalence of high blood pressure is low.
In the final study about blood pressure and slavery, Cooper et al., (1999) presented the data in notes form. They found out that hypertension was prevalent among Africans who had migrated to Europe than among the whites. This kind of presentation is difficult for the reader to understand. As a result, many may ignore the study yet it has an imperative message.
The Critique of Conclusions
In the first study, Cooper et al., (1999) concluded that hypertension is prevalent among the Americans. This study was biased because the sample population was small. Therefore, it cannot be generalized. Additionally, the fact that some Africans countries did not have clear medical records could have interfered with the findings and the conclusion. There is a very high possibility that hypertension was common in United States because they had clear and accurate records and not because majority of them are obese.
In the second study, Cooper et al., (1999) concluded that the higher the levels of angitensinogen in one’s body, the higher the risk of hypertension. This conclusion is biased because there are a number of factors like diet and stress that affect the levels of angiotensinogen in one’s body, yet Cooper et al., (1999) did not explore them.
In the final study, Cooper et al., (1999) concluded that hypertension was common in slaves. This conclusion cannot be generalized because the researchers reviewed secondary data. Additionally, the sample population was small.
It is difficult to understand the cause of hypertension. This is because environmental and physiological factors play a significant role in the occurrence of the disease. Additionally, there are confounding factors, which have not been identified, yet they are responsible for the occurrence of the disease. This could be the reason why some people had the genes responsible for the disease yet they did not have hypertension. Therefore, researchers should conduct studies about the causes of hypertension.
Cooper, R., Rotimi, C., & Ward, R. (1999). The Puzzle of Hypertension in African-Americans. Scientific Americans , 56-63.