Original article

Journal of Stress Physiology & Biochemistry, Vol. 7 No. 3 2011, pp. 132-142 ISSN 1997-0838 Original Text Copyright 2011 by Yavari, Mashinchi Abbasi, Vahidi, Najafipoor and Garooci ORIGINAL ARTICLE
Effect of Exercise on Psychological Well-being in T2DM
Yavari Abbas1*, Naimeh Mashinchi Abbasi2, Reza Vahidi3,
Farzad Najafipoor4, Mirtaghi Garooci Farshi5
1 Physiology Student Department of Physical Education, National Public Health Management Center (NPMC), Tabriz University of Medical Sciences, Tabriz, Iran. 2 Psychology Student of Tabriz University, Tabriz, Iran;3 Assistant Professor of Healthcare Service Management, National Public Health Management Center (NPMC), Tabriz University of Medical Sciences, Tabriz, Iran 4 Endocrine Research Center, Emam Reza Hospital, Tabriz University of Medical Sciences, 5 Faculty of Psychology, Tabriz University, Tabriz. Iran Telefax: 00984113362081 Tel.: 00989366205275 Background: Type 2 diabetic patients (T2DM) experience health problems including psychiatric and
psychological complications that influence their general health. Since exercise has an additional effect on psychological improvement, we aimed to establish the role of exercise as improvement of psychological problems. Methods: 80 subjects with T2DM were assigned to take exercise for 90 minutes per session, 3 times a week for a period of 4 months. They answered the GHQ-12 questionnaire before and after the study project. Results: Questionnaires were scored by Likert model and entered the statistical analysis. Our findings
demonstrate a significant decrease in the mean GHQ-12 scores. [13.39 ± 5.89 to 8.52 ± 5.12 (p < 0.001)]. Factor analysis by Graetz's three-factor model suggests that factor I (anxiety and depression) associates with more improvement than the other factors.
Conclusion: Exercise improves psychological distress inT2DM and results in improved well-being.
Key words: T2DM, exercise, psychological well-being, GHQ-12, mental health JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
Type 2 diabetes, physical activity & mental health. ORIGINAL ARTICLE
Effect of Exercise on Psychological Well-being in T2DM
Yavari Abbas1*, Naimeh Mashinchi Abbasi2, Reza Vahidi3,
Farzad Najafipoor4, Mirtaghi Garooci Farshi5
1 Physiology Student Department of Physical Education, National Public Health Management Center (NPMC), Tabriz University of Medical Sciences, Tabriz, Iran. 2 Psychology Student of Tabriz University, Tabriz, Iran;3 Assistant Professor of Healthcare Service Management, National Public Health Management Center (NPMC), Tabriz University of Medical Sciences, Tabriz, Iran 4 Endocrine Research Center, Emam Reza Hospital, Tabriz University of Medical Sciences, 5 Faculty of Psychology, Tabriz University, Tabriz. Iran Telefax: 00984113362081 Tel.: 00989366205275 Background: Type 2 diabetic patients (T2DM) experience health problems including psychiatric and
psychological complications that influence their general health. Since exercise has an additional effect on psychological improvement, we aimed to establish the role of exercise as improvement of psychological problems. Methods: 80 subjects with T2DM were assigned to take exercise for 90 minutes per session, 3 times a week for a period of 4 months. They answered the GHQ-12 questionnaire before and after the study project. Results: Questionnaires were scored by Likert model and entered the statistical analysis. Our findings
demonstrate a significant decrease in the mean GHQ-12 scores. [13.39 ± 5.89 to 8.52 ± 5.12 (p < 0.001)]. Factor analysis by Graetz's three-factor model suggests that factor I (anxiety and depression) associates with more improvement than the other factors.
Conclusion: Exercise improves psychological distress inT2DM and results in improved well-being.
Key words: T2DM, exercise, psychological well-being, GHQ-12, mental health Type 2 diabetes Mellitus (T2DM) is a chronic ulcers, gangrene, and erectile impotence (Albright, disorder, which is characterized by hyperglycemia and glycosuria. High concentration of blood glucose Complications of chronic disorders such as diabetes may damage quality of life (Singh & macrovascular events in the heart and blood vessels Bradley, 2006). Furthermore, compared to the as well as microvascular complications including general population, the prevalence of psychological retinopathy, nephropathy, and neuropathy, which disorders such as depression and anxiety are higher can finally lead to blindness, kidney failure, foot among diabetic patients. The negative impacts of JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
emotional problems of the quality of life include impairment. ADA notes that emotional well-being is poor medical outcomes such as decreased adherence part of diabetes management (ADA, 2009). to medication, impaired self-care behaviors or According to US Department of Health and Human glycemic control, risk of cardiovascular Services, regular physical activity as a non- complications, increased rate of mortality, and high pharmacological intervention leads to multiple costs (Koopmans et al, 2009; Pouwer, 2009, p.670; physiological and psychological benefits that can improve glycemic control, overall health, and Several studies have shown that the quality of quality of life (Hayes et al, 2007, p. 37) life in diabetic patients is decreased as compared to Salmon (as cited in Zacker, 2004) states the healthy persons because their daily life can involve many restrictions, which may affect their mood, Exercise has long been recognized as an essential mental health, physical, and social function (Schram component of diabetes management. It appears to foster psychological well-being through the Ali and Barnard (as cited in Schram et al., 2009) expressed that "Individuals with diabetes have a 1) antidepressant effects, 2) anxiolytic effects, two-fold increased risk for depression, affecting and 3) increased resilience to stress. (p.142) approximately one in every five diabetes patients". Several theories have been supposed about the Depression is a leading cause of disability, work mechanisms of which exercise improve mental place absenteeism, lost productivity (Egede, 2005). health. One theory involves the production of Anxiety and diabetes- specific distress (for endorphins. These natural opiates are chemically example not accepting diabetes, worries about similar to morphine and have "pain-relief" effect. complications, concerns about food, feeling of guilt Exercise leads to a β-endorphin surge into the blood or shame, and distressing social interactions are also stream to provide post-exercise mood elevations. In common (Pouwer, 2009, p. 666). Self-confidence, animal studies, it has been found that exercise family life, and even general perceptions of health, increases levels of serotonin, dopamine, and and pain are negatively impacted by diabetes norepinephrine, which are associated with elevated (Nizami et al, 2005; Singh & Bradley, 2006).
mood. Recently, enhanced activities in the brain Physical inactivity could be a behavioral factor lobes and the hippocampus as well as increased linking depression and poor T2DM outcomes levels of "brain-derived neurotrophic factor (BDNF)" have been purposed. BDNF is thought to improve mood (Koehl et al, 2008). On the other In order to reduce the risk of late complications hand, exercise ameliorates many of the known of diabetes, permanent changes in lifestyle and vascular risk factors by positive effects on blood lifelong multipharmacological treatment are needed. pressure, LDL cholesterol, HDL cholesterol, aid in the loss of weight and visceral fat. The results psychological and social situation as part of the are the better glycemic control and improved quality medical management of diabetes. It also offers screening for psychological problems such as depression, anxiety, eating disorders, and cognitive According to Greist (as cited in Zacker, 2004), "the first research on the link between exercise and JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
Type 2 diabetes, physical activity & mental health. emotional health was begun in the late 1970s, with However, the GHQ-12 has been used for the an investigation made into running and depression". assessment of many other conditions in diabetic During the last few years, an increasing interest has been observed towards the impact of diabetes on patient's well-being because they must deal with Participants
their disease every day. Therefore, several validated Our study included 80 patients with type II measures have been used to assess the satisfaction of diabetes by the age of 34-70 years, which were patients with the treatment programming and their registered through hospitals of Tabriz University of quality of life. These measures, which are performed Medical Sciences. They were selected according to by using different questionnaires, have demonstrated certain criteria, such as diagnosed type II diabetes that improved glycemic control could improve the for more than one year; HbA1c≥6.5, taking oral patient's well-being status (Milenkovic et al, 2004). hypoglycemic agents without insulin therapy, The General Health Questionnaire-12 (GHQ-12), age≤70 years, and having no sever diabetic a self-assessing and screening instrument, and a measure of current mental health is one of the best cerebrovascular incidents. Baseline characteristics psychological well-being measures to detect and their changes are shown in Table 1.
psychiatric disorders in the general population and Instrument
within community or non-psychiatric clinical The GHQ-12 that has been adapted to many settings such as primary care or general medical cultures and languages was used in our study. It has outpatients. It was developed by Goldberg in 1970s, been used over the world and its numerous versions and was originally developed as a 60-item exist in different number of languages (i.e. Persian instrument but altered as versions like GHQ-30, language). It has been studied within various populations and has been validated in different This questionnaire assesses the respondent's nations (Makikangas et al, 2006; Montazeri et al, current state and asks whether it differs from his or 2003, Discussion section, para.1; Ozdemir & her usual state (Nizami et al, 2005). This self- Rezaki, 2007; Sanchez-Lopez & Dresch, 2008; Tait administered questionnaire focuses on two major areas- the inability to carry out normal functions and Each item of the GHQ-12 is rated on a four-point the appearance of new and distressing psychological scale and there are four scoring methods including: Likert method (a total score ranging from 0 to The GHQ-12 questionnaire has been known as a 36), Modified Likert scoring (that yields a total valid instrument in primary care settings beside the score from 0 to 24), GHQ method or bimodal other instruments such as GHQ-20, STAI, PSS, method, and C-GHQ method (both methods give a CHADS, WHO-QOL… (Nizami et al, 2005; Surwit total score 0 to 12) (Montazeri et al, 2003, Background section, para.1; Hankins, 2008, In the present study, we have evaluated the effect Background section, para. 5). In all methods, higher of exercise training on psychological well-being and scores indicate worse conditions (Gao et al, 2004; general health in T2DM patients by using the GHQ- Hankins, 2008, Discussion section, para.1; Sanchez- 12 questionnaire. We found no similar studies in literature, which have previously been performed. JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
Table 1. Baseline characteristics and after intervention changes.
44.77/55.22
P< 0.0001* The values that are not made bold present M ± SD While the longer versions of GHQ are normally three times a week in 90 minutes per session for a considered multidimensional, the GHQ-12 is period of 4 months under the supervision of sometimes regarded as a unidimensional measuring professional trainers. All types of exercise training of psychological health. However, several authors progressed gradually in intensity and duration at 60 have revealed at least two factors (Vanheule & % to 75 % of maximum heart rate and from 15 to 60 The proposed 3-factor model by Graetz is one of The aerobic exercise was performed using the commonly used methods, which was used in this treadmill, fixed bicycle, and eleptical ergometers study. Several studies have found that the Graetz's and the resistance training was performed by weight 3-factor model gives goodness-of-fit than the others machines. Furthermore, the combined exercise (Gao et al, 2008). Its validity and reliability have training included both the aerobic plus resistance been found in Persian version by Montazeri et al Before the interview and doing the trainings, all Procedure
patients were informed about the study design. They After a two-week run-in phase of exercise test, were received a questionnaire both before and after 80 subjects were randomly divided into different types of aerobic, non-aerobic, and combination During the study, 13 subjects were dropped out training groups. Training programs were performed due to adverse events, changing the therapy method JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
Type 2 diabetes, physical activity & mental health. or inadequate number of training sessions, and condition and the most negative mood state. Then finally 67 subjects entered the analysis process. the statistical analysis was performed using SPSS Statistical analysis:
Statistical analysis was done using SPSS. (16.0). Descriptive statistics suggests a mean GHQ-12 The results were evaluated statistically significant score of 13.39±5.89 (p<0.001) for the pre- by a two-tailed p value< 0.05. Furthermore, the data intervention state of participants and a mean score of are shown as mean ± standard deviation.
8.52±5.12 (p<0.001) for their post-intervention mood state. The mean difference was -4.86±3.96. In the present study, it was observed that women The participants answered the questionnaire in had mean scores of 14.05±5.75 and 9.54±5.54 two times, before and after the program. Due to the respectively before and after the exercise program. short form of the questionnaire, our subjects spent a The order of these scores for men was 12.56±6.06 Each item has four answer choices and we Furthermore, it was revealed that the p-value of scored the questionnaire using a 4-point Likert-type the difference between both genders was not scale from 0 to 3 that seems to produce a wider, statistically meaningful, however both pre-test and smoother, and more acceptable distribution of scores post-test scores for the men were less than the for a parametric analysis (Sanchez-Lopez & Dresch, women were (Table 2). In this study, the calculated 2008). This method generates a total score ranging value of Cronbach's alpha coefficient was 0.88.
from 0 to 36 with high scores show worse health Table 2: Gender Differences in Mean Scores
For factor analysis, we used the current 3-factor We evaluated the mean scores of each factorial dimension before and after the correlation of paired - Anxiety and depression (factor I, 4 items), samples. Of total 36 scores, related scores of the - Social dysfunction (factor II, 6 items) and; three factors are 12, 18, and 6 respectively. In this - Loss of confidence (factor III, 2 items).
way, the generated data in the present study is JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
Table 3: Data Based on Graetz 3-Factor Model of Factor Analysis
Comparing the other two dimensions, factor I glycemic control through increased insulin points were more affected by this intervention and sensitivity and improved glucose tolerance, changed its average score was significantly decreased at the lipid profile, and improved cardiovascular risk second questionnaire. However, we observed the factors. Psychological alterations include adherence lowest change in the mean score to the third factor. better to medication or diet regimens as well as The gender-related differential data in these factors changed lifestyle. These alterations will cause a revealed a similar order of reductions in mean scores reduction in the long-term complications of diabetes, for women, whereas the men showed the highest delayed progression of existing problems, finally difference in factor III and the second factor elevated mood, and enhanced quality of life demonstrated the lowest change in mean score.
(Albright, 2000; Hayes et al, 2007).
DISCUSSION
Depression in T2DM is associated with impaired effectiveness of exercise on the improved quality of diabetes self-care behaviors (Pouwer, 2009, p.670). life among T2DM patients that their meaningful Even depression may be a barrier to exercise reduced mean scores after the intervention initiation (Vickers et al, 2006). Physical activity confirmed this opinion. Therefore, we used the affords significant acute and chronic benefits for Persian version of the GHQ-12, for the assessment patients with type 2 diabetes. The chronic benefits of exercise effects on quality of life in these patients.
are more numerous than acute effects, emphasizing Although other questionnaires have been used to the need for regular exercise for these patients. evaluate the effect of exercise on type 2 diabetic patients' well-being, using literature search we found Regular physical exercise as an alternative no previously published studies that have used the treatment for stress motivates people to adopt better 12-item GHQ for this aim. Our results confirm the findings of researches that have used other Exercise as different types (aerobic, resistance, questionnaires as instruments for assessing. For or combined form) acts as a therapeutic tool to example, Kucukurslan et al (2009) obtained ameliorate the emotional problems of diabetic improvement in the SF-36 mental component scores after an exercise program including resistance mechanisms. Regular physical activity improves training and home-based walking in diabetic JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
Type 2 diabetes, physical activity & mental health. patients. In another study that SF-36 and WBQ-12 We observed no difference between genders in questionnaires were used for measuring mental the p-value of mean scores; however, male patients health, it was shown that the aerobic, resistance obtained lower scores in both times of answering the exercise or both have significant effect on well- questionnaire. This suggests that compared to the being status, while, resistance exercise was better women, men have lower problems and this pattern is than aerobic or no exercise for improving physical similar to the general population; that is women are more likely than men to have a high GHQ-12 score (Ozdemir & Rezaki, 2007; Purdon & Eren, 1995, Our results confirm the findings of previous researchers such as Surwit et al (2002) indicating that "stress management can improve glycemic However it is noteworthy that based on the control", they also support the data obtained by available evidence different models of GHQ-12 Albright (2000) found that "exercise can play a role dimensional analysis may show several factors in reducing stress". Furthermore, the results of the across various samples or among different versions present study are in line with the data suggested by and since our aim was not the evaluation of Zacker (2004), Arora, Shenoy, and Sandhu (2009), confirmatory factor analysis, so we chose the current who used the questionnaire of Bradley & Lewis and model of Graetz for the interpretation of our showed that general well-being was improved in type 2 diabetes after 8-week supervised exercise Factor analysis in this research revealed that the training. In addition, they are the same as the study highest improvement was obtained in the anxiety- of Praet and van Loon (2007) that have focused on depression factor that has been recognized as a the benefits of various types of exercise to improve common co-occurrence diabetic complication. All of the psychological problems and general well-being the patients showed less improvement in the in diabetes or Martyn-Nemeth, Vitale, and Cowger confidence factor. After adjustment of the triple (2010), who demonstrated an improvement in factors, they were compared with each other and psychological parameters by a culturally focused meaningful mean differences were observed between "FI-FIII" and "FII-FIII". Where as the Besides, our study is consistent with the study of difference of the mean changes between "FI-FII" El-Rufaie with coauthors who revealed the presence was statistically meaningless. Therefore, it suggests of psychiatric disorders among type 2 diabetic that comparing with the other factors; the confidence patients by using the GHQ-12; however, their aim dimension has shown the least changes.
was not examining the link between psychological The order of changes in women was similar to morbidity and exercise (El-Rafaie et al, 1999).
overall changes (i.e. FI > FII > FIII), whereas the changes of those factors in the male group had coefficient was 0.88, similar to the obtained result another trend (i.e. FIII > FI> FII). In other words, by Montazeri with coauthors (0.87), which was the first confirmatory study of general population in JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 7 No. 3 2011
In the present study, although we did not focus In conclusion, our findings demonstrate that on social, education, and economic classes, we exercise program improves psychological distress observed the high prevalence of the first factor including anxiety and depression in type 2 diabetic (anxiety-depression) in women. This could be patients and results in the improved quality of life, contributed to their occupational state, because most well-being, and finally better glycemic control in of them were housekeeper. This parameter plus these patients. Thus, exercise could be considered as illiteracy or low grade of education level in this a justifiable public-health approach and group not only can result in worse psychological interventions such as life style changes using symptoms of diabetes, but also lead to their exercise and diet will have important roles in long- unawareness about the disease, denial reactions, and lasting management of disease. However, it is better the most limited social communication.
As expected, after the study design, the exercise- ACKNOWLEDGMENTS
adherence was significantly increased in women and This research was supported by a grant from the considerable number of them as well as the men National Public-Health Management Center continued their exercise programs. Furthermore, (NPMC), and with a co-operation of Endocrinology there was not a mean score of the GHQ-12 for the & Metabolism Unit of Sina hospital (Tabriz identification of depression and the other aspects of well-being through Likert scoring in Iranian REFRENCES
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