Cardiovagal Modulation, Oxidative Stress, And Cardiovascular Risk Factors In Prehypertensive Subjects

Literature Review

The article “Cardiovagal Modulation, Oxidative Stress, and Cardiovascular Risk Factors in Prehypertensive Subjects: Cross-Sectional Study” by Ramkumar Thiyagarajan, Pravati Pal, Gopal Krushna Pal,  Senthil Kumar Subramanian, Zachariah Bobby, Ashok Kumar Das, and Madanmohan Trakroo examined prehypertension in young adults. The article provides significant results on prehypertension among young adults where it is linked to augmented oxidative stress, as well as decreased cardiovagal modulation (Thiyagarajan et al., 2013). The title of the article clearly reflects the content of the entire paper from the introduction to the conclusion where the authors provides information regarding the connection between prehypertension amongst young adults and the augmented oxidative stress and changed cardiovagal modulation. This is evident throughout the article as the conclusion of the article provides a clear summary of the topic (Lloyd-Jones et al., 2006). The authors organized the article in a logical manner that makes it easy through read through by providing the different headings. In addition, the article is easy to follow; however, the language is not general and only fits students pursuing nursing and related fields and not general audience. Ultimately, it is evident from the article that it is free from grammatical and typos errors that makes the article and excellent one for research purposes.

The introduction of the article provides great information that is appropriate for the study. The authors start by introducing the concept of prehypertension as those persons with systolic blood pressure (BP) that range from 120-139mm Hg or diastolic BP that ranges from 80-90mm Hg. The authors further underscores the fact that this description is founded on the increase in risk of cardiovascular complications that are linked to level of blood pressure that was previously taken to be normal (Grotto, Grossman, Huerta & Sharabi, 2006).  In addition, the article further provides appropriate information when the authors argue that the reduced cardiovagal modulation is a primary indicator for forecasting prospect cardiovascular diseases and morbidity that is linked to premature aging, prehypertension, as well as hypertension (Thiyagarajan et al., 2013). In the article, appropriate information in the introduction that captures the topic is that oxidative stress is generated by unevenness between reactive oxygen elements along with the antioxidants in the genetic system.

The literature reviewed in the article is relevant in the introduction and is comprehensive. The authors used a range of literature from different authors to further provide detailed information concerning the association between prehypertension and augmented oxidative stress, as well as altered cardiovagal modulation in younger adults. Accordingly, the literature used in the article ranges from different authors that have explored the same or related topic where the information is relevant to the current study and makes the introduction part great through the information that is provided. For instance, Venza , Visalli , Cucinotta , Teti & Venza (2012) emphasizes the relationship between prehypertension and increased oxidative stress and decreased modulation. These articles reviewed by the authors in the introduction demonstrates how appropriate the literature that were used by the authors. This is an important strength of the article because the literature reviewed by the authors succinctly and reliably reflects the topic under investigation making the article an incredible source for research in the nursing field (Venza, Visalli, Cucinotta, Teti & Venza, 2012). Furthermore, the literature that was reviewed in the introduction is up-to-date and provides current literature that is relevant to the current study under investigation. The authors of the literature have great knowledge on the link between prehypertension and increased oxidative stress and decreased cardiovagal modulation, which means that they command a massive knowledge on the subject.

Aim of the Study

Additionally, the study appears original from the introduction because of the concepts that the authors used. This apparent from the definition of prehypertension where the authors defines prehyptension using 17^th report of The Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. This definition provides basis for the entire article as the authors use the definition to provide information regarding the topic under investigation (Thiyagarajan et al., 2013). In fact, at the top of the first page of the article it is indicated “original article”, which makes the concept of association between prehypertension and amplified oxidative stress plus declined cardiovagal modulation original all through the paper.

The aims of the of the study follow a logical way where it is assessing the link of cardiovagal modulation, oxidative stress, in addition to cardiovascular risk factors in youthful plus middle-aged prehypertensive participants. This aim provides a clear picture of what the paper will cover, thus providing the reader with what the article plans to explore at the introduction part. However, the authors do not clearly state the aims because it is not easy to identify them at the end of the introduction and needs a careful reading to identify these aims (Lloyd-Jones et al., 2006). The study did not provide the null hypothesis because the authors never mentioned this hypothesis in the introduction part.

The design of the study was that of cross-sectional study that targeted subjects in hypertension screening camps in Puducherry, India. In addition, the design of the study targeted young (20-39 years plus middle-aged adults (40-60 years).  This study design was consistent with the aims of study investigating the association between prehypertension and increased oxidative stress plus declined cardiovagal modulation in youthful and middle-aged persons. Therefore, the study used a design method that was appropriate and consistent with the aims.

In the study, the authors did not undertake a pilot study in the article as it is not indicated in the methods part of the study. The final sample of 178 participants was the representative of the entire study population drawn from hypertension screening camps in the area of study that was in Puducherry, India. Nonetheless, one limitation of the sample was that it recruited more males than females in the younger prehypertension group as compared to other groups in the study. This would influence the observations since young persons are vulnerable to develop prehypertension as compared to young females (Thiyagarajan et al., 2013).

Control group in any study plays a leading role in providing a basis of comparing the results in a study and the authors in this particular study used the control group to get reliable and valid results. Control group in the study was an important consideration of the authors as they included the normotensive group to find the link between prehypertension and augmented oxidative stress with declined cardiovagal modulation. The control group in the study was appropriate because it allowed for better analysis of the results. Therefore, the control was appropriate for the study.

Study Design

The authors clearly stated the selection process of the needed sample for investigating the topic. The participants of the study were selected from the society by four hypertension screening camps carried in Puducherry, India. Thus, study recruited 294 out of 524 volunteers and the final sample was 178 participants. The inclusion criteria in the study included systolic BP of <140mm Hg, diastolic BP <90mm Hg, and aged between 20 and 60 years (Wu et al., 2008). On the other hand, the exclusion criteria included history of chronic diseases, cardiovascular diseases, diabetes, main autonomic deficiency, or kidney illnesses; sports people; treatment for prehypertension, as well as chronic diseases. Figure 1 shows how the selection process of groups in the study.

The study used The Global Physical Activity Questionnaire (GPAQ) to evaluate the physical exercise of the participants that was measured as metabolic comparables. However, the questionnaire has not been provided anywhere in the article, including the appendix part. Therefore, the authors never provided any figure or link of the questionnaire in the article. In addition, it is clear that the authors sought ethical approval from the Jawaharlal Institute of Postgraduate Medical and Research (JIPMER) Scientific Advisory Committee and Institute Human Ethics Committee. Also, the participants consent in the study was sought by the researchers. Thus, the study procedure was described to the participants, plus printed informed consent was obtained prior to their input in the research (Thiyagarajan et al., 2013).

The authors presented the results of the study in a coherent and unambiguous way providing a clear picture on the relationship between prehypertension and increased oxidative stress along with declined cardiovagal modulation among the youthful and middle-aged persons. The statistical tests were clearly mentioned in results section that provided a better understanding of the subject under investigation (Passariello et al., 2007). Throughout the results section, statistical tests were used adequately and appropriately. In addition, table 1 shows a clear data that was collected from the study that is presented clearly. The table has been divided into two groups: prehypertension and normotension. Also, in the stud, there is no missing data indicated by the authors.

The authors used numbers, percentages, and statistical values that ate accurate and clear in the entire results section. I find most of these numbers, statistical values and percentages very accurate and clear all through the results section. Furthermore, the numbers, percentages and statistical values provides a better insight regarding the topic. Consequently, if statistical tests had not been used in the study, then it cannot be justified because these values are important in a quantitative study of this nature towards getting the needed results.

The size of the sample used in a study should be appropriate in terms of size to guarantee valid and reliable results. The sample of the study that finally used was 178, which is large enough to justify the findings. This sample was appropriate for the study because it lies within the recommended range of 30% of the entire selected sample for consideration before the final sample was obtained through both the inclusion and exclusion criteria (Thiyagarajan et al., 2013). Additionally, the findings of the study are clinically significant for the study because the results reflect the question of the research that entailed the investigation of the relationship between prehypertension along with augmented oxidative stress and decreased cardiovagal modulation in younger and middle-aged adults. The results of the study were believable because they reflect the aims of the study (Pavithran, Nandeesha, Sathiyapriya, Bobby & Madanmohan, 2008).

Sample and Limitations

Conclusions

The authors critique and discuss the results of the study considerably. The authors assert that the primary results of the research is that younger adults with prehypertension has declined cardiovagal modulation, increased oxidative stress, as well as cardiovascular risk factors equal to that of the middle-aged persons. In addition, the authors argue that declined cardiovagal modulation is a vital indicator for prediction of prospect cardiovascular morbidity. The authors further claim that declined cardiovagal modulation in prehypertensive young persons (Pal et al., 2011). The authors further critique and discuss the fact that amplified oxidative stress parameters among young in addition to middle-aged prehypertensive persons plus well-built relationship of oxidative stress with prehypertension after changing for perplexing cardiovascular risks factors are consistent with results of past researches. Furthermore, the study critique that the limitation of the study is that it used more male participants than females increasing bias of the study. Thus, the results of the study are comprehensively discussed all through the discussion section of the article (Thiyagarajan et al., 2013).

The results discussed by the authors are in relation with other important literature on the topic. For instance, the authors cite the report of the Framingham heart research, which disclosed that the existence of many risk factors in middle-age persons, which grow the life span risk for cardiovascular diseases for the lingering duration plus lowers permanence by ten years. There are many other studies that have been used by the authors to provide comprehensive information on the topic. In addition, the authors confined themselves in their discussion on the methods and results of the study. This is important in allowing the reader to focus on the topic under study.

The conclusion of the study clearly reflects the results of the study. The conclusion of the article was that prehypertension among younger adults is linked to increased stress and changed cardiovagal modulation. In addition, the authors conclude that the risk factors for cardiovascular diseases in prehypertensive younger people were established to the same to those of middle-aged persons who are in the sunset zone for growth of cardiovascular dysfunctions (Gawel, Wardas, Niedworok & Wardas, 2004).

The source of funding for the article was from the Department of Science and Technology, and Government of India. Accordingly, the funding was made through the INSPIRE fellowship. In the article, the authors affirmed no conflict of interest. There is no statement of exactly how each author contributed to the article.

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