psychological therapies (note if someone close dies for example this can cause depression
and taking anti-depressant drugs doesn’t stop you from missing them it will not bring
them back). As the basic biological causes is known using certain drugs as an
intervention is common and can be very effective, there are different groups of drugs that
can be used these include Monoamine Oxidase Inhibitors, Tricyclics and new
antidepressants like Prozac. However the course of treatment depends on the outcome of
an original evaluation of the patient by a therapist, as mentioned before there is a variety
of antidepressant medications and psychotherapies that can be used to treat depressive
disorders. It all depends on how severe the depression is people with mild forms respond
well with psychotherapies alone, people with moderate to server depression benefit from
just antidepressants, however most respond best to a combination of the two treatments.
By combining both treatments they get the “best of both worlds”, by taking the
antidepressants they gain relatively quick symptom relief and by having psychotherapy
treatment they learn more effective ways to deal with life’s problems which include
depression. Again depending upon the patient’s diagnosis and severity of symptoms, the
therapist may prescribe antidepressant medication and/or one of the following forms of
psychotherapy; specific approaches, cognitive-behavioural therapy, interpersonal
psychotherapy, behavioural therapies and short-term dynamic and psychoanalytic
therapies. The use of drugs for treating depression has been subject to a great deal of
research and a review by Spadone, C 2002 which looked at the different research papers
involving the use of antidepressants, found that continued treatment with an
antidepressant can help treat depression and can also reduce the risk of depressive relapse
noted during long term follow up (between 18 months and 5 years) by at least 50%. A
study performed by Furukawa et al 2002 found that a combination of antidepressants
and a drug known as Benzodiazephine, it was found that patients prescribed with the
combination therapy were less likely to drop out from the treatment than those prescribed
just antidepressants alone. Although there is evidence indicating the benefit of combined
drug therapy and the treatment of depression, these potential benefits must be balanced
against the potential harm associated with the combination including drug dependency so
further research must be done to completely justify the findings. However a study
performed by Terry et al 2005 found that long term psychotherapy in combination with
antidepressants increases compliance and response rates in people with depression.
So it is known that depression can be treated with a number of medical procedures and
advice, but if the mental causes of depression were looked at again is there other ways to
treat depressive disorders? The studies performed by Judd et al 1996 and Mojtabai et al
(2004) showed that one problem individuals have that suffer from depressive disorders is
lack of physical activity so what effects does exercise have on an individuals mental
well being? Exercise has been proposed as an alternative to more traditional approaches
as mentioned above for treating depression (Hales et al 1987) but is this an effective way
for treating depression? There seems much evidence to support the idea that physical
activity has positive effects on depression, however the main problem that the present
research has is that it all mainly involves people who are not “classed” clinically
depressed, so how do we class people clinically depressed? Well if someone goes to the
doctors saying they are depressed the doctor will examine them and if they prescribe
some sort of intervention like time off work, prescribe drugs, or tell to you to go and see a
counsellor then you could be classed as clinically depressed but you have to be careful
because there is a very fine line between being clinically depressed and not. So when looking at whether exercise has a positive effect on depression you have to look at existing research which uses one of the following ways of categorising clinical depression; firstly the most widely used is the Beck Depression Inventory (BDI) this is backed up by a search I performed on “Pubmed” using the terms “BDI, depression” and results showed 1258 items that involved the use of the BDI method. BDI is 21 item self-report rating inventory measuring characteristic attitudes and symptoms of depression (Beck et al., 1961), scoring 16 or above classes the patient with clinical depression. There are also two other methods that can be used this are the; Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) or the International classification of diseases (ICD-10) and also the Research Diagnostic Criteria. Studies in clinically depressed populations have included both hospitalized and ambulatory patients, one study of hospitalized clinically depressed patients found significant reductions in depression among patients who were prescribed an aerobic exercise program but not in a control group who participated in occupational therapy (Martinsen et al 1985). A further study randomly assigned patients to 8 weeks of walking and jogging, recreational therapy, or a waiting list, depression scores decreased only in the walking and jogging group. However the severity of the patient’s depression has to be questioned in these studies if they were really clinically depressed then they would not perform the exercise prescription given to them because they could not be bothered to exercise so there is definitely question
marks on the validity of these tests. Morgan et al (1994) looked at fitness levels of psychiatric patients suffering from depression and non-hospitalized controls, what was found was that the psychiatric patients had lower levels of fitness when compared to the fitness levels of the non-hospitalized controls also it was found that patients who had a short (up to 61 days!) stay in hospital had higher levels of muscular endurance on admission than those who stayed longer (at least one year) even though they had similar initial levels of depression. however these findings come under some criticism people who suffer from clinical depression do not come depressed over night so if they are suffering from depression then its more than likely that they are not participating in regular exercise resulting in there fitness levels to be lower, also the more physically fit you are to begin with the less time you will stay in hospital, also a short stay of 61 days seems to be long so therefore this is questionable. Does lack of exercise cause depression or is it depression that causes lack of exercise? A study looked at the relationship between level of physical activity and risk of subsequent depression was examined using three waves of data from Alameda county study. Among subjects who were not depressed at baseline was those who reported a low activity were at significantly greater risk for depression at the 1974 follow-up than were those who reported high levels of activity at baseline. Associations between 1965-1974 changes in activity level and depression in the 1983 follow – up suggest that the risk of depression can be altered by changes in exercise habits. These results provide stronger evidence for an activity – depression link than do previous studies, and they argue for the inclusion of exercise programs as part of community mental health programs, as well as
for further studies that focus on the relation between life-style and mental health ( Camacho et al 1991). Another study looked at 10,201 male Harvard alumni, low levels of activity reported during initial interviews (in 1962 or 1966) were inversely related to self-reported physical-diagnosed depression in 1988. The relative risk of depression was 27% lower for men who reported playing 3 or more hours of sports each week than for those who reported playing no sports (Paffenbarger et al 1994). The Harvard alumni study, presents limited evidence for a dose-response association between levels of physical activity and depressive symptoms. While relatively few studies have produced concrete evidence that exercise has positive effects on depression, there are now a large number of studies that support the efficacy of exercise in reducing symptoms of depression. Further which the early research in this area suffered from a variety of methodological limitations (small samples, lack of random assignment, and lack of control groups), current researchers have addressed these design issues, and presently there are multiple studies that have utilized experimental designs or employed a randomized clinical trial approach. Meta-analysis provides one means of summarizing this growing body of primary research and identifying variables that may moderate the effect of exercise on depression. There have been several of these meta-analyses, McDonald and Hodgdon (1994) show that exercise does have an anti-depressant effect (however they did not use clinically depressed subjects!), Calfas and Taylor (1994) also had similar findings with healthy and risk adolescents although the number of studies involved was small. However in 1998 a meta analysis was performed by Craft and Landers which only was concerned with clinically depressed subjects in 30 studies
showed a difference in levels of depression following exercise in moderate to severe depression, so there was some sort of relationship going on but you have to be careful because there is relatively little other studies that back up these findings.
As there is some kind of relationship between exercise and depression (although the evidence is fairly weak), has exercise actually got an antidepressant affect? There have been some credible physiological and psychological mechanisms that have described why exercise might have this kind of affect. The thermogenic hypothesis suggests that a rise in core body temperature following exercise is responsible for the reduction in symptoms of depression. It has been explained that increases in temperature of specific brain regions, such as the brain stem can lead to an overall feeling of relaxation and reduction in muscular tension. However current research has focused on exercise and levels of anxiety rather than exercise and depression (although it has been proposed to have the same affect). (DeVries, HA, 1981). Another hypothesis is known as the endorphin hypothesis which is another theory as to how exercise affects the body, however this certain theory has not been extensively researched so there is relatively little scientific support, except in the fact that extended exercise has been proven to increase the
secretion endorphin (Moore, M. 1982), but to date it has not been proven to whether or not this secretion has an affect on the control of depression. The final physiological theory and the most researched is known as the monoamine hypothesis which is based on the theory that exercise increases the brains aminergic synaptic transmission (Ransford, C,P 1982). Basically the monoamines in the brain such as serotonin and dopamine have an improved transmission rate when exercising occurs, so if you look back at the biology
of depression then you can see that any increase in neurotransmitters such as serotonin and dopamine is beneficial to the depressed patient. As the relationship between exercise and depression continues to grow, more and more theories are being put forward to why exercise improves depression; there have been the physiological theories mentioned above but also the psychological theories to why there could be a relationship, basically there two main psychological theories, the distraction hypothesis and the self efficacy hypothesis. The distraction theory is about the idea that diversion from painful stimuli leads to an improved state after exercise. This statement has been backed up by the experiment Bahrke and Morgan (1978) performed, it was found that distractions from the stress of daily life through exercise caused a beneficial decline in anxiety and depression. The self efficacy hypothesis works on the idea that one must first have the confidence that he or she can perform a certain behavior, it is thought that when a depressed individual simply becomes motivated enough to perform the act of exercise his or her self-esteem is raised and in turn, depression lessens. However Hill (1965) broke it down into 8 different sections he looked at the strength of the association between exercise and depression it was found that the relationship was quite good but when compared to something like exercise and coronary heart disease then the relationship was no where near as strong (maybe because this is more easier to deal with?), he then looked at the consistency does the putative relationship often occur and the answer was yes, specificity how tight is the relationship between exercise and depression, well we know that the area is poorly researched also how many of the variables surrounding depression are controlled? So is it really exercise that is the causing affect?, does inactivity precede
the onset of depression?, not very well sitting around doing nothing will cause depression whatever, is there a certain amount of exercise needed to be performed (dose response)?, again not very well researched there are big individual differences because a lot of people do not find exercise has any intrinsic cheerfulness, is it possible that biological mechanisms could explain the effect of exercise on depression?, possibly (serotonin, endorphins levels etc), coherence would this mechanism fit with other known mechanisms yes probably, and finally scientific evidence, well we know that this area is very poorly researched, there is some but not enough and not enough high quality evidence there are a lot of studies but not enough evidence.
Basically there is something going on involving this area of exercise and treatment of clinical depression, but so far there is relatively very little high quality evidence that can back up this notion that exercise is good way of treating depression, also much of the research performed has some methodological flaws that can hinder the area, for example many of the studies have not used control groups or random assignments, also as depression can be such a serious illness many of the subjects were completing other methods of treatment which makes it difficult to distinguish which of the treatments is
having the affect. Also many of the studies use relatively small sample sizes which is understandable when considering the nature of the topic so it becomes difficult to generalize the findings, so bigger sample sizes are needed. Also better work is needed on the relationship between the drug treatments and exercise. So there is an extensive gap in the literature that needs to be filled before we can strongly say that exercise is associated with a decrease in clinically depression in patients.
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