Mental Health Effects Of Exercise Health And Social Care Essay

Objectives: To determine the mental health effects of exercise for people with anxiety disorder, affective and mood disorder, and substances use disorder.

Search Strategy: Clinical trials on anxiety disorder, affective and mood disorder, and substances use disorder (August 2010) were searched based on Cochraine, MEDLINE, PsycINFO, PsycheArticles, Sport Discuss, and PubMed database. References from relevant papers were also inspected.

Selection Criteria: All randomized controlled trials comparing any intervention where physical activity or exercise was considered to be the main or active ingredient with standard care or other treatments for people with anxiety disorder, affective and mood disorder, and substances use disorder.

Data Collection & Analysis: Citations and abstract were inspected and the quality is assessed, and the data were extracted.

Main result:

Ten randomized clinical trials met the inclusion criteria. Trials assessed the effects of exercise on physical and mental health for affective/mood and anxiety disorder, also the consumption change on illicit drugs and alcohol. Overall number leaving the trials were <50%. Most trials use exercise as adjunct treatment to standard care and found significant (p<0.05) effect of exercise towards improve mental state and addictive behavior. Exercise were found to improve physical fitness (VO2 max = 0.48 mlO2/min). There is no significant effect of exercise activity and intensity in anxiety disorder but significant for depression and substance use disorder (DASS Cohen’s d = 0.82, Depression: d= 0.57, Anxiety d= 0.92, Stress d= 0.76; PDA >60%). Exercise effect is higher than standard care alone or adjunct treatment with meditation. Exercise dose differs for underlying fitness level, physical wellbeing, and age. Green environment act as catalyst while smoking behavior block the fitness outcome.

BACKGROUND

There are about 450 million people suffered from mental and behavioral disorders worldwide. One person in four will develop one or more of these disorders during their lifetime [1]. Mental disorders contribute to almost 11% of 1996 disease burden worldwide and it is predicted that it will increase up to 15% in 2020 [2]. By looking at local context, almost half of Australian population experience mental illness at some point of their lifetime [3], which contribute 13.3% of the total country burden of disease and injury in 2003 [4].

A good mental health enable individual to handle day-to-day events and obstacles, work on their goals, and function effectively in society. Minor disturbances in mental health could with delay early intervention will not only a suffered to the individual but also a burden to their families and society considerably. The economic and personal costs of mental illness are also the major concerned in social and public health. Exercise was believed to enhance individual’s ability to cope with and manage their mental disorder apart from its well documented physical health benefit. Improved quality of life is particularly important for individuals with severe and enduring mental health problems as exercise may alleviate depression, low self-esteem and social withdrawal.

 Mental disorder is usually determined through clinical diagnoses using the ICD10 or DSM-IV criteria. In Australia, anxiety disorder, affective and mood disorder and substances abuse are the main mental disorder in this country [3] thus will be used in this review.

Description of the condition

Anxiety Disorder

Anxiety disorders are a group of illnesses characterized by persistent feelings of high anxiety, extreme discomfort and tension which will significantly interferes with their daily life. Its often come out of the blue and presented with intense physical symptoms such as breathlessness, palpitations, sweating, trembling, feelings of choking, nausea, abdominal distress, dizziness, pins and needles, feelings of losing control and/or feelings of impending doom[4]. Anxiety disorders also affect the way a person thinks, feels, and behaves. There is different number of anxiety disorders which include panic disorder, agoraphobia, social phobia, generalized anxiety disorder, obsessive-compulsive disorder, and post-traumatic stress disorder, which most often begin in early adulthood and common among women than men [5, 17]. It is reported that lifetime prevalence of total anxiety disorder was 10.6% – 16.6% [23].

Affective Disorder

Affective disorder characterized by dramatic changes or extremes of mood which include manic or depressive episodes, and often combinations of the two. They may or may not have psychotic symptoms such as delusions, hallucinations, or other loss of contact with reality [9]. This disorder could be categorized into depression, dysthymia, mania, hypomania, and bipolar affective disorder [5]. For lifetime prevalence, the corresponding pooled incidence rates were 6.7 per 100, 3.6 per 100, and 0.9 per 100 for respective major depressive disorder (MDD) dysthymia disorder and bipolar I disorder categories [16].

Substance use disorder

Substance use disorder refers to mental and behavioral disorder resulting from psychoactive substance use such as alcohol, opoids, others stimulants, hallucinogens, tobacco and volatile disorders [5]. The focus of this paper will look at the study on alcohol and illicit drugs. In the short term, the individual may perceive these effects as quite desirable however, prolonged and heavy usage may result in physical harm, dependency, and withdrawal problems and long term psychological damage or social harm. This will leads to intoxication, harmful use, dependence, and psychotic disorders [5]. Harmful use is diagnosed when damage has been caused to physical and mental health. Dependence syndrome involve strong desire to take substance and difficulty in control the use, physical withdrawal, tolerance, neglect of alternative pleasure and interest, and persistent use despite harm to self and others. Point prevalence of alcohol use disorder has been estimated to be around 1.7% globally, which higher rate among men 2.8% to women 0.5% [18]. While, the burden attributable to illicit drugs was estimated at 0.4% of total disease burden, and economic cost of this harmful drugs dependents and use in the United State has been estimated to be USD98 billion [22].

Exercise and mental health

There is no single mechanism has yet been found to adequately explain the diverse range of mental health effects possible through physical activity participation. The plausible mechanisms for psychological change through physical activity and exercise fall into one of three broad perspectives as explained by Mutrie (2003) where there is biochemical changes such as increased levels of neurotransmitters; physiological changes such as improved thermo-genesis, muscle and cardiovascular function and, suggested psychological changes such as social support, sense of autonomy, improved perceptions of competence, enhanced body image, self-efficacy and distraction.

Important of review

There is a growing recognition that physical activity can enhance mental health (Faulkner 2005). Regardless by this fact, there is still limited evidence to suggest the effects of exercise on anxiety disorder, affective and mood disorder, and substances abuse reported in the population characterized by these mental illnesses. The purpose of this review is to focus specifically on methodologically rigorous trials in updating current consensus concerning the potential role of exercise in improving the mental health of individuals with anxiety disorder, affective and mood disorder, and substances use disorder.

OBJECTIVES

To determine the mental health effects of exercise programmes for people with anxiety disorder, affective and mood disorder, and substances use disorder, and factors that enhance the effect.

METHODS

Types of participants

Clinically diagnosed adult (aged 17 and above) with diagnosed anxiety disorder, affective and mood disorder, and substances abuse using any criteria, with any length of illness and in any treatment setting.

Types of interventions

Physical activity or exercise will be the main or active elements intervention studied in this review. As a result of most clinical subjects is under treatment, intervention in conjunction with others will be considered as well. Only interventions which address mental health outcome of exercise, its dosage, and factors attribute to effectiveness will be included.

Others exercise study that potentially discussed the outcome of enhancing physical exercise intervention on mental health status will also will be included for prospective review.

Types of outcome measures

Outcomes were groups according to assessments of mental and physical health, and were grouped by different disorders, factors attribute to effectiveness, and dose exposure outcome. The primary outcome will be mental state score.

Search methods for identification of studies

Search is restricted to English literature will be used as more time is needed for paper translation.

Electronic searches

The MEDLINE, PsychInfo, PsychArticles, PubMed, Cochrane, SportDiscuss, SAGE, Springerlink, and JSTOR articles and journal databases (August 2010) were searched using the phrase : [(physical* and (therap* or intervention)) within the same field of title, abstract or index term fields) or ((fitness* or sport* or gym* or exercis* or * danc*) in title, abstract and index fields Reference) or (*exercise* or danc* or physical act* in interventions field in Study)] and also different phrases for disorder studied is added in term, reference and study field: anxiety disorder (panic disorder*or agoraphobi*or social phobi* or generalized anxiety disorde* or obsessive-compulsive disorde*or post-traumatic stress disorde*), mood or affective disorder (depressio*or dysthymi*or mani*or hypomani*or bipolar affective disorde*), and substance use disorder (alcoho*or cocain*or heroi*or ampletamin* or illicit dru*).

Data collection and analysis

In the selection process, abstracts of research papers were independently assessed by the searches for relevance. When abstract was unclear and disagreements occurred, the full report is required and the assessment process repeated. With resolved disagreement, data is extracted from each study and even from unpublished source for the purpose of this review.

Studies are then independently assessed for its methodological quality base on sequence generation; allocation concealment; blinding; incomplete outcome data; selective reporting of the results; and any other biases identified.

The standard Risk Ratio and Odd ratios at 95% confidence interval (CI) will be used as interpretation of treatment effect. As a result of continuous data outcome in mental health trials are often not normally distributed, criteria for inclusion is used where the standard deviations and means for the endpoint measures on rating scales is obtained and the standard deviation (SD), when multiplied by 2 had to be less than the mean [19].

Even though some degree of loss to follow up data must lose credibility [19], all trial in the main analysis will be included all. Only study with outcome of more than 50% participation will be interpreted.

RESULT

Results of the search

There are about 264 electronics reports inspected and of these, 254 studies were excluded on the basis of their abstracts. Ten randomized controlled trials (Carta 2008; Jerome 2008; Oeland 2010; Doyne 1987; Kenzor 2008; Murphy 1986; Sinyor 1982; Merom 2007; Ng 2007; and Brown 2010) were included in this review. Additional 6 studies (Mackay 2009; Jokela 2010; van Hauvelen 2006; Perrino 2009; Brown 2005; and Tart 2010) were included for prospective view on exercise effectiveness factors that could be used for implementation of study.

Included studies

We included ten randomized controlled trials (Carta 2008; Jerome 2008; Oeland 2010; Doyne 1987; Kenzor 2008; Murphy 1986; Sinyor 1982; Merom 2007; Ng 2007; and Brown 2010). All studies have been published since 1982 which illustrates growing attention to the role of exercise as a form of adjunct therapy for the focused mental illnesses. One study (Merom 2007) investigated the effects of an exercise programme on anxiety disorder where brisk walking exercise and others exercises were implemented. The 8 -10 weeks program lengths, with exercise dose of >30 minutes duration, done five times per week have shown a remarkable decrease of anxiety among patients in the intervention group.

Compare with others mental illness studies; there are numerous studies on affective and mood disorder. Reviewed studies shows that exercise does work to reduce depression and anxiety in bipolar patients with just one hour per week of simple group brisk walk exercise for 8 months lengths (Carta 2008); and for major depression patient, the positive outcome were observed after 150 minutes per week group walking for 8 week length program. Greater total time exposure will give better significant outcome for bipolar patient (Ng, 2007) and the severity of affective/mood psychiatric problem does not influence the exercise outcome (Jerome, 2008). Oeland et al (2010) have demonstrate that, increased in physical activity will tremendously leads towards better body physiology changes among these patient. Their depression level were found to have further decrease with high level intensity exercise compare to low density exercise at equivalence dose (4 times per week with 60 minutes duration) of exposure (Doyne 1987).

The main outcome measured for Drugs and Alcohol use disorder is the percent day abstinence (PDA). Structured group exercise were found leads towards better PDA outcome as adjunct therapy for drugs addicts and alcoholic patients (Murphy 1986; Sinyor 1982; Brown 2010) at the minimum of 8 weeks intervention (Murphy, 1986) to 12 months intervention(Sinyor 1982). The effective dose reported in these studies is 20-70 minutes exercise routine for the least once a week. Unstructured exercise has demonstrated lower outcome in Kendzor (2008) and Sinyor (1982) studies, verified by their respective intervention group and control group outcome.

1. Methods: All trials were randomized. The duration of the trials ranged between 8 weeks (Murphy 1986) and 24 months (Ng 2007).

2. Participants: All trials included people diagnosed with anxiety disorders, affective or mood disorders, and alcohol or drugs use disorder using DSM-IV criteria (Carta 2008; Jerome 2008; Oeland 2010; Doyne 1987; Kenzor 2008; Murphy 1986; Sinyor 1982; Merom 2007; Ng 2007; and Brown 2010). Only one study does not use in- or outpatients (Murphy 2007). Participants ranged in age from 18 to 80 years.

3. Setting: Three studies were conducted in community centre (Kendzor 2008; Murphy 1986; Sinyor 1982), one offered in the university (Doyne 1987), and the rest is offered in and outpatient services.

4. Study Size: The smallest sample size is 16 participants (Brown 2010) and the largest number of participants in sample is 620 people (Kendzor 2008).

5. Interventions: All study using exercise as their main activity used to measured the outcome. The experimental conditions identified in each of the included studies differed in exercise duration and intensity. The exercise activity intensity are from a simple walking to high intensity supervised structured aerobic exercise. Most selected studies implement consistent duration of exercise 20-60 minutes five times per day for the least 8 weeks. Only well structured supervised intervention implements increase intensity (Sinyor 1982; Brown 2010). All exercise programmes were in addition to participant’s usual care except intervention in Murphy, Pagano and Marlat (1986) study.

6. Control interventions: Standard care: Participants continued with their usual treatment in Carta 2008, and addition with Group Cognitive behavior therapy and just education benefit of exercise for Merom 2007, Oeland 2010, Doyne 1987, Kendzor 2008, Sinyor 1982 and Brown 2010. There are two control groups in Murphy, Pagano & Mariat (1986) study which one group in meditation intervention while the others were not in either exercise or meditation. These participants were university student not with any treatment for excessive alcohol intake. Only Ng 2007 does not implement control in their intervention.

7. Outcomes:

Depression Anxiety Stress Scale (DASS-21) is a 21 item self report questionnaire designed to measure the severity of a range of symptoms common to both Depression and Anxiety. Each item is scored from 0 (did not apply to me at all over the last week) to 3 (applied to me very much or most of the time over the past week). Merom 2007 and Ng 2007 used this scale.

World Health Organization Quality of Life BREF Version (WHOQOL-BREF) is scale to assesses physical health, psychological, social relations and the environment on a five-point scale where 1 = poor QofL and 5 = good QofL. Carta 2008 and Oeland 2010 use this scale.

The Clinical Global Impression – Severity scale (CGI-S) is a 7-point scale that requires the clinician to rate the severity of the patient’s illness at the time of assessment, relative to the clinician’s past experience with patients who have the same diagnosis. Considering total clinical experience, a patient is assessed on severity of mental illness at the time of rating 1=normal, not at all ill; 2, borderline mentally ill; 3, mildly ill; 4, moderately ill; 5, markedly ill; 6, severely ill; or 7, extremely ill. Ng 2007 used this scale.

The Clinical Global Impression – Improvement scale (CGI-I) is a 7 point scale that requires the clinician to assess how much the patient’s illness has improved or worsened relative to a baseline state at the beginning of the intervention. Rated as: 1, very much improved; 2, much improved; 3, minimally improved; 4, no change; 5, minimally worse; 6, much worse; or 7, very much worse. Ng 2007 used this scale.

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a screening battery designed to measure attention and processing speed, expressive language, visual-spatial and constructional abilities, and immediate and delayed memory. Jerome 2008 used this measurement for to records schizophrenic patient activity.

Symptoms Checklist-90 (SCL-90) is used as a screening measure of general psychiatric symptomatology. It includes dimensions measuring somatization, obsessive-compulsive, depression, anxiety, phobic anxiety, hostility, interpersonal sensitivity, paranoid ideation, and psychoticism. This was used by Jerome 2008

Center for Epidemiologic Studies depressive scale (CES-D) is a short self-report scale designed to measure depressive symptomatology in the general population. The items of the scale are symptoms associated with depression which have been used in previously validated longer scales. It was found to have very high internal consistency and adequate test- retest repeatability. Validity was established by patterns of correlations with other self-report measures, by correlations with clinical ratings of depression, and by relationships with other variables which support its construct validity. This was used by Jerome 2008.

Beck Depression Inventory (BDI) is a 21-question multiple-choice self-report inventory, used for measuring the severity of depression from a psychodynamic perspective. In its questionnaire is designed for individuals aged 13 and over and composed of items relating to symptoms of depression such as hopelessness and irritability, cognitions such as guilt or feelings of being punished, as well as physical symptoms such as fatigue, weight loss, and lack of interest in sex. Used by Doyne 1987 and Kendzor 2008

Figure1: Methodological quality summary: review authors’ judgments about each methodological quality item for each included study.

Adequate Sequence Generation

Allocation Concealment

Blinding?

Incomplete Outcome data addressed

Free of Selective Reporting

Free of Others Bias

Merom et al 2007

+

+

+

?

+

–

Carta et al 2008

+

+

+

+

+

–

Ng et al 2007

+

?

?

–

+

–

Jerome et al 2008

+

+

+

–

+

–

Oeland et al 2010

+

+

+

+

+

+

Doyne et al 1987

+

+

+

+

+

–

Kendzor et al 2008

+

+

?

?

–

–

Murphy et al 1986

+

+

+

+

+

–

Sinyor et al 1982

+

+

+

–

+

–

Brown et al 2010

+

+

?

–

+

–

Risk of bias in included studies

Allocation: All study reported as randomized.

Blinding: None of the studies were double-blinded. The reported results may exaggerate estimates of treatment effect and None of the studies reported any test of blinding

Incomplete outcome data: Most of the studies have withdrawal from the sample population as the highest reported were in Sinyor (1982) study which around 60% remains in the study, which were due to self withdrawal from being participant after undergone first phase of treatment.

Selective reporting: Most study report the mean and standard deviation.

Others source of bias: most of the study have tendency of selection bias, measurement bias and error due to effect of confounding especially effect of group therapy and regular undergone treatment.

DISCUSSION

Ten studies were included in this review. Overall, these studies showed that exercise therapy can have an impact on mental health outcomes like mental state and general functioning with no adverse effects.

There are various studies looking at the impact of exercise towards anxiety in non-clinical samples using DASS and SCL-90 questions tools, which were excluded for reviews apart from the reason of its non-clinical trial study design. Compare to usual treatment alone and GCBT, prolonged and frequent exercise conducted in group for at least 8 weeks were significantly effective in reduce anxiety, depression and stress among patients diagnosed with generalized anxiety disorder, panic disorder, and social phobia. Similar effect was observed for bipolar disorder and major depression in addition to their usual treatment, regardless of the psychiatric condition severity and exercise intensity (Jerome 2008).

Clinical trials have shown high day abstinence from drugs and alcohol best occurs in well structured, high intensity group exercise among alcoholic and drugs addict, in addition to their usual treatment for the problem. Kendzor 2008 study has demonstrated there was no effect of individual low density physical activity towards reducing the heavy drinking habit.

We could conclude that, the minimum effective dose for exercise to mental status is 40-60 minutes session, repeated 3-5 times per week for continuous 8 weeks duration. This dose works for low endurance brisk walking exercise with a proper warming up session. Increases in exercise intensity will give better physical fitness, and ideal weight management. Type of exercise, its intensity, and dose is modified base on underlying fitness level and age (Jerome 2008; Jokela 2010; van Hauvelen 2006; Perrino 2009).

Others factors that could affect exercise effectiveness is the exercise environment. Mackay & Neill 2009 study shows that there is significant relationship between anxiety changes and green environment. Exercise intensity works for depression (Brown 2005; Jerome 2005) and substance use disorder (Sinyor 1982; Brown 2010) but not for anxiety (Mackay & Neill 2009). It is found that smoking behavior will delay exercise fitness effect (Tart 2010).

AUTHOR’S CONCLUSION

Implication of practice

People with mental illness

The results of this review indicate that there are various benefits of exercise to individuals with anxiety disorder, mood and affective disorder, and substance use disorder, which can improve components of mental health by participating in structured group exercise. Limited number of studies on proper intensity and dose of exercise towards the improvement of mental health for the different population group and underlying psychiatric problems has cause difficulties for medical practitioner to come out with clear guidance to the patient. Physician, physiotherapist, professional physical trainers, and health educator should be consulted for better support and advice towards implementing exercise as treatment intervention. It is clear from this study that, exercise works as adjunct therapy for identified psychological problems and high intensity exercise work for substance abuser and depression patient. The best effect of exercise is that it conducted in group and being supervised. Patient with anxiety does responds to high intensity exercise but the effect is not much different compare to low intensity exercise. Current guidelines for lifestyle activity and exercise appear do not really work for the justified mental disorders. Therefore, accumulating 40-60 minutes of proper physical activity on most or all days of the week is a good guideline. This should be continued for minimum of 8 weeks for a better mental status outcome. Cessation of smoking will further ensure better health benefit.

For physician, health educator, physiotherapist and professional physical trainers

Regular exercise is known for its physical, mental, and social benefits. It is a multidimensional approach that requires physician, health educator, physiotherapist and professional physical trainers to ensure patients to become and staying active for its physical and psychological benefit. Proper information guidelines to patients are essential in the long run. Health practitioners should also be equipped with this latest information and as well emphasize on the safety of intervention to avoid negative effect of exercise especially muscle injury if not properly done. Side effect of medication and structural barrier for intervention (socio economic status, infrastructure) as well as underlying medical condition should also be considered before recommend this intervention to the patients. In others word, exercise intervention is personalized to suit individual situation.

For policy

Structural barrier may limit patient participation into exercise intervention in mental disorder treatment. It is shown from the studies that patients with mental health have better chance to improve their morbidity when adhere into exercise intervention as adjunct treatment for their underlying psychological problems. Proper guidelines for health practitioners and patients are required for better communication to deliver the information for both. Multidisciplinary approach should be emphasized in this practices which could profound positive impact on patients health and wellbeing. More time is required to deliver and explained this message to patient as the program is personalized to fit individual underlying social and physical wellbeing. Policymakers should consider the implementation of this multidisciplinary programmes approach within their respective treatment facilities. They should also consider to provide better exercise facilities in the community thus as well promotes green environment and the establishment of well structured community exercise group program for a long term benefit. There is chances that continuous exercise program could be used as prevention of acquired mental health problems due to life-style changes. More evidence on this is required and with such evidence support, cost benefit or cost effective analysis of preventive exercise intervention in mental health could be established. In long-standing, this could be helpful in reducing pharmaceutical cost for mental health in a country.

Implication for research

General

There are various established measurement used in reporting mental health outcome thus cause difficulties to compare the study results. It is recommended that in research practice for mental health outcome, the measurement should be standardized.

Specific

It is important in future for us to have a clear define duration, frequency and intensity of exercise program for each mental health disorder; considering the underlying medical and physiological wellbeing of individual. Study on the changes of fitness level due to the intervention is progressively in practices, and in any future research it should be reported in the record. Mental health is a complex discipline where there is no clear cut point of disease and always presented with a comorbid condition of either other mental disorder or chronic diseases. This should as well to be considered in future research especially in intervention study. It is also a challenge in the research of this area to ensure the finding is free from cofounding effect of biological and social diversity in the complex global society. In the end, with the establishment of complete study in mental health area could contributes a better theoretical background to explain the mechanism of this diversification. This will help as well towards low cost of treatment in mental health disorder in the future.

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