Advanced Biology Final Project
This study is the second attempt to monitor the health of students at Oyster River High School. The first study, which was completed at the end of 2001, looked at many general factors that have potential influence on student health. This study picked up some of the loose strings from earlier on as well as narrowed its focus to the specific effects of stress on health.
Some things in the first study worked well; overall conclusions of student health over the given period showed definite fluctuations, indicating large outbreaks of illness at certain points. Other things did not go so well; data was not collected frequently nor tabulated accurately. Much of the data taken was not used, either because it could not be quantified or because there was too little of it to draw any definite comparisons. Due to new methods of collecting and tabulating data, accuracy of information in this second study was kept very high.
Before the project could begin it was important to define stress in relation to our research. This is an often ambiguous and confused concept. The definition of stress for this study is as follows: stress is an internal process that occurs when a person is faced with a demand that is perceived to exceed the resources available to effectively respond to it. Furthermore failure to effectively deal with the demand has important undesirable consequences. In other words, stress is experienced when there is an awareness of a substantial imbalance between demand and capability, under conditions where failure to meet the demand is perceived to have unwanted consequences.
The purpose of this project is two-fold:
1. To design an interactive database entry application that allows easy input and management of data in a large-scale study.
A windows-based application was used to help with management of the data collected from students via questionnaires. The format for this application was based directly on the questionnaires that were given to students. A detailed description of these questionnaires can be found under "Project Design and Methodology." Because the application follows the visual layout of the questionnaires, using the application to input data is very user-friendly. Data from the application is stored in pre-defined Microsoft Excel files. Using this method allowed us to easily generate graphs and analyze the collected results.
2. To demonstrate the effect of stress on the immune system
As an observation from the first study conducted at ORHS, the health of students tended to decline dramatically in correlation with periods of intense study directly preceding vacations. One might speculate that as a typical student spends long periods in school without breaks, his immune system is negatively affected by loss of sleep and increased stress levels. By comparing the health of individuals with high stress to others with low stress, this study examined these factors on a school-wide scale.
When the symptoms from the original study were graphed over the three-month interval from which information was collected, there emerged definite trends among the data. Data tended to cluster into three groups – cold, flu, and fatigue-related systems. Although certain symptoms can often be traced to multiple ailments, in general they tend to correspond to specific diseases. Frequent coughing, for example, is generally caused by throat irritation resulting from the common cold. However, it can also indicate lung diseases such as bronchitis and asthma, and could be caused simply by an individual's allergies.
The group that plotted temperature with student health determined a direct correlation between student health and average daily temperature. Though temperature itself does not contribute to a decline in student health, it often confines students indoors, where the combination of low humidity and poor air circulation provides ideal conditions for viruses to spread. Students are also likely to exercise less in the winter – a factor that may inhibit the proper function of their immune systems.
In continuing the disease study, we decided to concentrate on stress, which is commonly thought to be a factor responsible for the decline of health in an individual. In this study we have defined health as a balance between the physical, mental and emotional states of a person. Our questionnaires reflected this by asking students to rate each of these factors daily. We have used these values to evaluate an "average health rating" for each student.
In prehistoric times, the physical changes in response to stress were an essential adaptation for meeting natural threats. Even in the modern world, the stress response can be an asset for raising levels of performance during critical events such as a sports activity, an important meeting, or in situations of actual danger or crisis. If stress becomes persistent and low-level, however, all parts of the body's stress apparatus (the brain, heart, lungs, vessels, and muscles) become chronically over- or under-activated. This may produce physical or psychological damage over time.
In regards to physical health, stress is also known to decrease the efficiency of the immune system; many stressors have been found to lower the number of cells in the blood that fight infection. When the immune system is weakened, humans become more susceptible to illnesses such as the common cold, flu, as well as more serious illnesses. Chronic stress appears to blunt the immune response and increase the risk for infections. Once any person catches a cold or flu, stress can exacerbate symptoms.
In regards to mental health, stress has been shown to have a significant effect on the brain, particularly on memory. The typical victim of severe stress suffers loss of concentration at work, at school, and at home and may become inefficient and accident-prone. Severe stress may even break down the blood-brain barrier, a physiological mechanism that helps protect the brain from toxins, bacteria, and other potentially harmful substances that may be carried in blood. A 1999 study looked at the effect of chronic stress on learning in middle school children. It was found that the physiologic responses to stress could clearly inhibit learning. The study also found that training in stress and anger management led to significant improvements in the children's emotional balance, focus, and relationships.
In regards to emotional health, severe stress is associated with the onset of depression or anxiety. It has been hypothesized that people genetically predisposed to depression also may have a tendency to become involved in high-stress situations. Certainly, stress diminishes the quality of life by reducing feelings of pleasure and accomplishment, and relationships are often threatened.
Typical stressful situations include financial difficulties, health problems, home instability, lack of free time, job security, dieting, etc. In this project we have focused on the situations that are most pertinent to Oyster River students. In the data analysis of the last study, for example, it was noted that students felt considerably better after breaks than they did before. This could be attributed to several factors, and we will try to determine the cause with the help of our new questionnaires and data analysis methods. The updated questionnaire will address habits in the sleep, exercise, and diet patterns of subjects. In analyzing the data, we will make note of special events that occur in the school – for example, testing periods like sophomore testing and finals. We will also identify any vacations or long weekends.
When our bodies experience stress they prepare to combat, prevent, and heal injuries. In the brain, hypothalamus triggers the pituitary gland to release ACTH, which in turn gives off two types of chemicals. The first type is catecholamines, which exist as epinephrine or adrenaline. These chemicals have the effect of arousing the body. This chain of events makes our heart rate increase, and causes us to feel more energetic and alert. If the body experiences stress in the form of an injury, the second chemical, corticosteriods, resists the negative effects of the stress.
According to Ceuesta College, there are five quick ways to detect stress. First, it is possible to check for muscle tension by checking for tension or pain in the face, shoulders, and back. Breathing should also be checked for any rapid increases. Hand temperature can be checked by moving and holding one’s hand to one’s neck. If the temperature of the hand is noticeably cooler than the neck, then the body could be experiencing stress. A third indicator is perspiration; this is an involuntary stress response caused by the secretion of certain stress hormones. Rapid pulse is another indicator; pulse rates higher than 75 beats per minute may indicate that the body is responding to a stressor. It is also possible to check for rapid, shallow breathing. People who are tense often tighten their stomach muscles and breathe through their chests. We have carefully considered these factors and applied them to this study at ORHS.
PROJECT DESIGN AND METHODOLOGY:
There were approximately 100 students participating in the study. Of these, 65 students provided full and accurate information. There were two types of questionnaires given to students (both attached). The first is the "one-time" questionnaire that determined the health habits of students. There were 11 data points on this questionnaire. The second survey given to students was a packet that contained a series of short, identical questionnaires, one of which was to be filled out every school day. There were 10 data points on the daily questionnaire.
All students were assigned unique ID numbers that were used to keep track of their individual input over time. Both the teacher and Dan and I had copies of assigned ID numbers for each student, to make sure that ID numbers were not forgotten. An example of one such ID-name sheet is attached. The ID numbers were also used to correlate results between the daily and one-time questionnaires. An additional sheet is attached entitled "ID Assignments and Information" which describes the specific ID numbers given to various classes as well as other related information. Teachers were also given an information sheet ("Information on the Study for Teachers") which explained some common concerns pertaining the study. This sheet is also attached.
Data was collected daily from 5 classrooms, representing all four grade-levels. Data was generally analyzed by graphing multiple data types against one another – for example, an individual’s health vs. the number of hours he spent sleeping during a week, or doing homework. This data was also analyzed against others and against time.
Based on the scope of the study described, there were approximately 25,000 data points that were entered into the database. The created application has the ability to open an instance of an excel spreadsheet, as well as use the Excel graph functions by programming against the Excel object model.
The most logical method of working with such large volumes of data was to input data into preformatted tables in Excel (.xls) files. The structure of the cells/columns in the tables these sections referenced was directly based on the design of the questionnaires. As mentioned earlier the user interface of the application was also designed based of the questionnaires. Thus there are two basic sections to the user interface of the application. The first deals with data input for the "one time" questionnaire and the second deals with the "daily" questionnaire. For data analyzation; graphs of different data correlations were linked to the tables, so that the graphs are automatically modified as data is entered. The application also manages all error handling to ensure a high standard of inputted data. A "screen shot" of the application as well as a print outs of all the code used and a CD containing the Visual Basic project files is included with this project evaluation.
As discussed earlier, students were given an average health rating that was based on their emotional, physical, and mental health. Each day students had the opportunity to rate themselves on a 1-4 scale in each of these categories. The 1 value was used to specify the best health and 4 used to specify the worst health. Thus it should be noted that health levels approaching 1.0 on the graph are the best health levels. We are quite confident in the validity and accuracy of the data because of the relatively large numbers of responding students. For example it can be noted that on the graph discussing average test numbers per day the students responded that there were an average of a little over 3 tests the day before April vacation, and nearly none the day of return. Such a cycle is a common practice among teachers.
The first two graphs found in this packet show the total health of students over the one and a half-month period the study was conducted. The fist graph (labeled 1) shows each of the 3 health sectors separately. The second graph (labeled 2) shows an "average trend line" that will be used to refer to student health. This is the average of all three of the health levels that are collectively referred to as "average student health" this is labeled simply as "average" and is found in red on the graphs.
As can be observed from this second graph student health fluctuated between 1.4 and 1.9 in the duration of the study. These values were also the end points of the graphs. Students entered the study feeling their worst, and left feeling their best. Other quick points of interest show that students felt noticeably better following the "early release day" on may 9th, however their health generally remained unchanged following the April break (April 23-27)
There was a relatively large fluctuation in the number of hours that students spent working throughout the week. (Time spent working, as described in our questionnaire, included both time spent on homework and time spent working jobs.) While the average time worked by a student stayed at a relatively constant 2.5 hours until mid-May, it became quite sporadic after that. On May 17 the average student spent an all-time low of 1.3 hours working, followed by 2.1 hours the next day (a Friday, not surprisingly). Yet, the next Monday this figure jumped to an incredible 3.9 hours per student.
Interestingly, there was no correlation between these sporadic work periods and students' health, but with the exception of these dates the graph plotting the number of hours worked vs. health showed a fairly strong correlation. It could be suggested from this that the health of people is indeed negatively affected by overworking.
Graph 4 shows perhaps some of the most conclusive data from the study. This graph compares the number of hours of sleep students accumulated in comparison to their average health levels. It was hypothesized that as hours of sleep increase, health should also increase. Again because better health is represented by lower values, the hypothesis would show up as an inverse relationship between the two lines. Such a trend can be clearly seen especially in the first part of the graph. Over the period of time 4/14/01 to 5/10/01 the graphs mirror each other, sometimes with a slight delay between action and re-action. Following the 10th of May the relationship can still be seen, however it is not quite as apparent.
From the background reading we had learned that the tensions of unresolved stress frequently cause insomnia, generally keeping the stressed person awake or causing awakening in the middle of the night or early morning. Thus having more stress, and less sleep could decrease a person's health. Such a situation appears to be demonstrated by our test subjects and this graph. Sleep or lack thereof seemed to affect mental health the most. This is shown in graph 5. Mental health fluctuated the most out of the 3 health levels described in the study. It is hypothesized that lack of sleep would cause one to be drowsy and un-alert thus earning a low mental health rating.
Of the 65 students surveyed on the initial questionnaire, 19% responded with a “1”, 38% with a “2”, 31% with a “3”, and the remaining 12% with a “4”. These four groups of students were then compared in the categories of physical, mental, emotional, and overall (averaged) health. There was generally little variation between the health of those who responded with 2’s or 3’s, but the graphs that compared the “1” respondents with the “4” respondents turned out to be very conclusive.
The difference in health between high-stress and low stress was perhaps most noticeable in their physical health (graph 6); regarding this criteria, the relation between students with low and high stress was actually inversely proportional. Low-stress students recorded their best health on the days that high-stress students were feeling their worst. On four days, in fact, every one of the low-stress students reported perfect health (“1” out of 4). High-stress students, however, recorded as bad as an average 2.5 on one of these four days.
On other interesting thing about this graph was that there were a high average number of tests (graph 10) given by teachers on those days that the greatest difference in health occurred. This may suggest that high-stress students allowed the pressure of upcoming tests to take a toll on their health.
The difference between high-stress and low-stress student health was least noticeable regarding mental health (graph 7); on some days, all students in both categories gave themselves 1’s for mental health. Despite this consideration, there were still generally substantial differences between these two types of students. On the first day on which the survey was distributed, low-stress students averaged a 1.5, while high-stress students averaged 3.5.
Emotional health (graph 8) showed the same types of correlations observed in the physical and emotional graphs. Again, often all of the low-stress students reported perfect health on several days, while there were only three such days for high-stress students.
Throughout the project analysis we evaluated many factors that could potentially be stressors and effect health levels. The discussion covers some of the more interesting results that were found. Because stress can be caused by a variety of factors it would be very difficult if not impossible to map a direct relationship between one particular stressor and the health level of a person. In this study of high school students, several areas showed promise. We found relationships between sleep levels and overall health, particularly mental health. The hours a student worked also correlated strongly with their overall health levels.
The most conclusive results were found when comparing students who had indicated low and high stress levels in the "one-time" questionnaire. Overall students who specified low stress levels had vastly better health than students with high stress levels, in all three of the determined health categories.
“Searching For The Biological Pathways Between Stress And Health.” http://annualreviews.org/ 1997 http://publhealth.annualreviews.org/cgi/content/full/18/1/437
This re-published report from the department of Health Care and Epidemiology at the University of British Columbia takes a biological view at the links between stress and health. The report set criteria to evaluate potential physiological markers of chronic stress. Five areas were reviewed in detail; these include glycosylated proteins, the immune system, homeostasis, peripheral benzodiazepine receptors, and the waist-hip ratio.
“Health Report - Effects of Stress on the Immune System.” Australian Radio National 04/27/98 http://www.abc.net.au/rn/talks/8.30/helthrpt/stories/s10844.htm
Research from the U.S. is showing considerable effects of stress on the immune system - from how well the flu vaccine produces immunity right down to how long it takes a wound to heal. The report also classifies characteristics that determine the vulnerability of an individual to be affected by stress.
“Regular Exercise May Protect Against Negative Effects Of Stress On Immune System.” The University Of Colorado at Boulder. 11/12/1998.
This University of Colorado At Boulder study suggests that choosing to exercise regularly in moderation may help guard against the negative effects of stress on the body's immune system. The study, based on experiments conducted with rats, concludes that people who exercise regularly are less likely to get sick after stressful situations than people who do not.
“Effects of Stress on the Immune System.” Radio National: The Health Report. 04/27/1998.
This interview with Dr. Ronald Glaser (from the Ohio State University College of Medicine) discusses the many experiments that he and his wife have conducted to research and demonstrate the effect of various stress factors on the immune system. In one experiment, they injected a group of medical students with the hepatitis B vaccine. Blood samples of the students over a period indicated that antibodies and T-cells of students who showed more stress and anxiety responded much less significantly than in “unstressed” students.
Blakeslee, Thomas R. Emotions and the Immune System. 2/25/2000.
Going beyond physical factors that are stress contributors (lack of sleep, exercise habits, etc.) this source references a number of studies that demonstrated the tendency of individuals undergoing emotional trauma to be more susceptible to illnesses than healthy individuals. One massive study in Finland examined the health records of 96,000 widowed people and found that their probability of dying was actually doubled in the week after losing their mate.
Boris Masis Daniel Noronha
Phone: 868-3067 Phone: 749-6056