Understanding Research Reports

The article “cross sectional study of effects of drinking green tea on cardiovascular and liver diseases” is a 1995 publication by K Imai and K Nakachi in the British Medical Journal volume 310, number 6981 from page 693 to 696. Imai and Nakachi (1995) sought to find out the connection between consuming green tea and serum markers concentration with special focus on whether green tea helps in preventing cardiovascular diseases as well as liver disorders. Imai and Nakachi (1995) investigated the levels of serum total cholesterol, triglyceride, high density lipoproteins (HDL) and low density lipoproteins (LDL) after consumption of green tea. In addition, the researchers investigated the levels of serum hepatological markers such as aspartate aminotransferase, alanine transferase as well as ferritin upon consumption of green tea.

To accomplish the purpose of this study, Imai and Nakachi (1995) selected 1,371 men in Yosimi, Japan with an age of more than 40 years.

This study was a quasi-experimental study. This is because the researchers made observations on the living habits of the participants as well as assaying blood samples collected from the subjects. Moreover, the study took a prospective approach to study a cohort, which is characteristic of quasi-experimental designs. Questionnaires were administered to collect data on participant’s lifestyles. To collect data on concentration of different types of cholesterol, triglyceride and hepatological markers, the authors assayed (biochemical and immunological) blood samples from the subjects. This study identified that an increase in consumption of green tea (> 10 cups per day) led to decreased LDL and very low density lipoproteins, decreased triglyceride as well as a decrease in total serum cholesterol. There was also an increase in levels of

HDL. High consumption of green tea led to decrease in aspartate aminotransferase, ferritin and alanine transferase. The authors therefore concluded that consumption of green tea has the advantage of protecting against cardiovascular diseases and liver disorders.

“Childhood trauma and risk for chronic fatigue syndrome association with neuroendocrine dysfunction” is authored by Christine Heim, Urs M. Nater, Elizabeth Maloney, Roumiana Boneva, James F. Jones and William C. Reeves and published in 2009 in the Archives of General Psychiatry Journal volume 66, number 1 from page 7280. Heim et al. (2009) sought to confirm that there is an association between childhood trauma and predisposition to chronic fatigue syndrome (CFS). Moreover, the authors of this study sought to find out whether neuroendocrine dysfunction, common in CFS, is connected with childhood trauma. The main health condition that Heim and colleagues (2009) sought to study was chronic fatigue syndrome. The authors of this study then sought to study how CFS is related with two other conditions: childhood trauma and neuroendocrine dysfunction.

To evaluate the relationship between CFS, childhood trauma and neuroendocrine dysfunction, the researchers investigated various forms of childhood trauma including physical trauma and neglect, sexual abuse, as well as emotional abuse and neglect. Factors that were studied to identify psychopathology were anxiety, depression and posttraumatic disorder. Neuroendocrine dysfunction was understood by studying the response of salivary cortisol upon awakening. The study was conducted among adults who resided in Georgia, USA. 113 CFS patients as well as 124 persons who were free of CFS (control subjects) were selected from among 19,381 adults.

This study used an observational design. This is because the study took a casecontrol approach and assessed the participants retrospectively. CFS individuals were identified through review of medical history as well as physical and biochemical analysis of samples from subjects. Childhood trauma was assessed using a questionnaire, neuroendocrine dysfunction was determined using laboratory assays of salivary cortisol whereas psychopathology assessment was measured using an assessment scale. Heim et al. (2009) identified that CFS patients had a higher record of childhood trauma compared to control subjects. Psychopathological symptoms (e.g. depression) were higher among CFS individuals that in control subjects. The risk of developing chronic fatigue syndrome increased six times if one had been exposed to childhood trauma with this risk being more pronounced in persons who had been sexually or emotionally abused as well as those who had experienced emotional neglect. The higher the level of exposure to childhood trauma, the higher the risk of CFS; and in cases where posttraumatic stress disorder coexisted with childhood trauma, the risk of CFS was even more pronounced. Concentrations of salivary cortisol reduced upon awakening in CFS patients who had experienced childhood trauma but not in CFS patients who had not been exposed to childhood trauma.

The authors of this study came up with two main conclusions. Firstly, it was confirmed that childhood trauma risks individuals to development of CFS. Secondly, Heim et al. (2009) confirmed that neuroendocrine dysfunction, which is common in CFS cases, is related to childhood trauma.