Gestational diabetes is one of the most common complications of pregnancy (Spaight et al, 2016). The prevalence of gestational diabetes in developed and developing countries is increasing (Donovan et al, 2016). It has been reported to occur in 1–14% of pregnancies globally (Schwarz et al, 2015) and 3.4% of pregnancies in Iran (Jafari-Shobeiri et al, 2015). Gestational diabetes results in adverse outcomes in pregnancy and childbirth, including development of type 2 diabetes, gestational hypertension, and increased risk of childbirth and congenital anomalies due to impairments in blood glucose control (Shang and Lin, 2014; Ekhtiari et al, 2016).
Knowledge of the risks of gestational diabetes can increase women's fear, anxiety and depression, and women who have gestational diabetes mellitus have been shown to worry more than other women (Byrn and Penckofer, 2015). Despite the fact that diabetes has a strong link with stress and tension, physical and mental stress also leads the body to diabetes (Çakir et al, 2014; Kaviani et al, 2014). The effect of daily stress on diabetes control is less recognised. Endocrinologists have found that stress and psychoactive stimuli cause hyperglycaemic conditions and increase blood pressure in women with diabetes (Zare et al, 2013; Khani et al, 2017). Decreasing stress in people with diabetes is therefore important (Seidi et al, 2016).
Relaxation is one of many complementary treatments and is harmless during pregnancy. It includes mental imagery, music therapy and massage (Rahimi et al, 2014). Relaxation has an effect on the sympathetic system, which can increase calm and reduce mental stress in pregnant women (Limsanon and Kalayasiri, 2015; Shojaie et al, 2017). It can increase the secretion of endorphin hormones, reduce the secretion of adrenaline hormones, reduce cortisol levels, and reduce heart rate and blood pressure among pregnant women (Rahimi et al, 2014). There are several methods for relaxation including mind-body techniques, which are led by three factors: respiratory training, progressive relaxation and guided imagery. These aim to improve mental, physical and patient's abilities. Given the effect of relaxation on decreasing depression, anxiety and stress, this method can be used to improve women's mental health during pregnancy (Seyed Ahmadi Nejad et al, 2015; Howland et al, 2017; Unger et al, 2017).
Women with gestational diabetes are considered to be high-risk, and their care is important. There are few studies on the effects of mind-body relaxation techniques on fasting blood glucose, systolic and diastolic blood pressure. Therefore, this study was conducted with the aim of investigating the effect of relaxation on fasting blood glucose and blood pressure in women with gestational diabetes mellitus.
Methods
This was a quasi-experimental study with two groups with the aim of examining the effect of relaxation on fasting blood glucose and hypertension in women with gestational diabetes mellitus.
Study participants
Participants included 80 women with gestational diabetes mellitus who were referred to the antenatal clinic at Imam Khomeini Hospita, Tehran. Women were divided into two groups, each with 40 participants. After confirmation of the researcher's skills in relation to relaxation by a senior midwifery practitioner, subjects were recruited using a convenience sampling method. Participants were screened using the depression, anxiety and stress scales (DASS) and were selected based on the inclusion and exclusion criteria shown in Table 1. During the study, five women in the control group and two women in the intervention group were excluded from the study due to the need for insulin injections. Two participants were excluded from the study before the fifth week. They could attend intervention sessions but were not included in the sample size. These participants were replaced with new ones.
| Inclusion criteria | Exclusion criteria |
|---|---|
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The researcher explained the purpose of the study and asked particpants to sign the written consent form during face-to-face interviews. To prevent contamination between samples, the control group was recruited first.
Intervention
The intervention group was taught mind-body relaxation techniques for 10 weeks. Groups of 1–4 participants were taughts at weekly 45-minute sessions using a role-playing technique and educational pamphlet. At the beginning of sessions 1–2, the researcher laid on the bed in a lateral position and performed respiratory techniques and exercise. Participants were asked to do the exercises in the presence of researcher and then at home twice a day with the help of educational CDs. Performance of the techniques at home was recorded in the appropriate checklist: the first checklist was used to record relaxation exercises at home, while the second was for weekly checkups, questions related to exercise, relaxation problems, dietary observation, and a reminder of the next visit.
At the end of each week, the researcher followed up with participants in the intervention group by telephone to emphasised the importance of performing the exercises regularly. The educational content of each session covered important and common issues in pregnancy, the mechanism and causes of diabetes, the nature of stress and its impact on the body, stressors in pregnancy, and vaginal birth. The researcher provided an overview of the educational materials provided and the exercises performed in the previous session. In addition, exercise checklists were collected, questions were answered, and the appropriateness of conducting exercises was monitored.
The control group received routine education in clinic, with information on disease, self-care, diet, and exercises for pregnancy. It must be noted that the participants in control group also had high-risk pregnancies and for this reason, they had more frequent antenatal sessions than low-risk pregnancies. During the study period, they were also visited once every 10–14 days but did not receive a phone call. At the end of the study, the educational pamphlets were given to the control group.
Data collection
Fasting blood glucose, systolic blood pressure and diastolic blood pressure were measured in both groups before the start of the study and immediately after the experimental group had finished their last session. A third checklist was used by the researcher to record systolic and diastolic blood pressure and fasting blood glucose before and after the study.
Data gather ing tools included a mercury sphygmomanometer; scales and a meter rule to measure weight and height, respectively; a demographic data questionnaire; the DASS instrument for measuring anxiety and depression and the three checklists.
Demographic data were collected by a questionnaire is including questions on personal and medical data. The DASS questionnaire was designed by Lovibond and Lovibond (1995) and included 21 questions on depression (7 questions), anxiety (7 questions) and stress (7 questions). Questions were scored on the Likert scale from 0 (low) to 3 (very high), with a higher score indicating the worse condition. Women with moderate and severe stress levels were not included in the study for homogeneity of samples. Validity and reliability of this instrument were confirmed by Henry and Crawford (2005). The scale also was validated for the Iranian population with coefficients of 0.72, 0.84, and 0.87 for anxiety, depression and stress, respectively (Shafaie et al, 2018).
The questionnaires were given to 10 faculty members, and necessary amendments were incorporated into the questionnaires after collecting their comments. The booklet of relaxation techniques that was provided to the intervention group was prepared after reading books and articles and consultations with experts in the field of relaxation. For content validity, the booklet was provided to 10 faculty members. For face validity, it was given to 5 women, who reviewed and corrected it in terms of ease of comprehension.
Data analysis
Data were analysed using SPSS version 21. Descriptive (mean, percentage and standard deviation) and inferential statistics (Chi-square (c2) test, Fisher's exact test, paired-t test) were used for data analysis and P<0.05 was considered statistically significant.
Results
In this study, 80 women undergoing dietary treatment were divided into the groups of 40 and were compared before and after the study. The groups were homogenous in terms of education, family history of diabetes, place of residence, employment and income adequacy (P>0.05). The results of the independent t-test showed that the two groups had no statistically significant differences in terms of age, number of pregnancies, number of living children, number of abortions, gestational age, weight, height, mean systolic and diastolic blood pressure and fasting blood glucose. Therefore, the groups were homogenous in terms of midwifery and demographic characteristics (P>0.05), systolic blood pressure (P=0.558), diastolic blood pressure (P=0.712) and fasting blood glucose (P=0.484) before the study.
No statistically significant difference between the mean fasting blood glucose score before and after the study was observed in the control group (P=0.051). Fasting blood sugar in the control group showed no changes before and after the study period, but in the intervention group, this difference was statistically significant and reduced (P<0.001) (Table 2).
There was a statistically significant difference between the mean systolic blood pressure before and after the study in both groups (P<0.001)—this was increased in the group control and reduced in the intervention group. There was also a statistically significant reduction in the mean diastolic blood pressure before and after the study in the control group (P=0.02). There was a small reduction in the intervention group, although this was not statistically significant (P=0.461) (Table 3).
| Intervention group Mean ± SD | Control group Mean ± SD | P value† | |
|---|---|---|---|
| Systolic blood pressure | |||
| Before intervention | 109.7 ± 9.604 | 111.1 ± 11.237 | 0.558* |
| After intervention | 101.0 ± 8.181 | 117.8 ± 10.675 | <0/001* |
| P value | <0/001* | <0/001* | |
| Diastolic blood pressure | |||
| Before intervention | 69.2 ± 8.664 | 68.3 ± 12.163 | 0.712* |
| After intervention | 68.2 ± 5.723 | 65.6 ± 9.883 | 0.151* |
| P value | 0.461* | 0.020* | |
t-paired and independent t-test.
Statistically significant at P<0.05
The independent t-test showed that systolic blood pressure and fasting blood glucose were significantly different between the groups (P<0.001). The intervention group showed lower mean scores in systolic blood pressure, but the mean score of diastolic blood pressure did not show any significant difference after the study in both groups (P=0.151).
Discussion
Fasting blood glucose levels
The mean post-study fasting blood glucose was 99.60 mg/dl (5.53 mmol/l) in the control group and 94.10mg/dl (5.22mmol/l) in the intervention group. Changes in fasting blood glucose levels in the control and intervention groups were +1.05 and -4.08, respectively. This means that participants in the control group saw an increase in fasting blood glucose levels after 10 weeks. In the intervention group, the relaxation practices, educational pamphlets and phone call follow-ups contributed to significant decrease in fasting blood glucose levels. At the second measurement (10 weeks after the first), there was a significant difference in fasting blood glucose levels between the control (5.53 ± 0.21) and the intervention groups (5.22 ± 0.28) (P<0.001).
This confirms findings in the study by Kaviani et al (2014) in Shiraz. In another study, Asaadi et al (2013) compared the effectiveness of muscle relaxation education on reducing anger and blood glucose in patients with type 1 and type 2 diabetes, and found that the mean blood glucose in both groups was significantly decreased. A study by Seidi et al (2016) on the effectiveness of bioavailability feedback on depression, anxiety and blood glucose in patients with type 1 diabetes showed that relaxation reduced anxiety and blood glucose, but had no effect on their depression. Stress and anxiety can increase the long-term survival of hormones such as cortisol, epinephrine, norepinephrine, glucagon, growth hormone, prolactin and leptin by activating the hypothalamus-pituitary-adrenal axis, resulting in an increase in blood glucose (Zare et al, 2013; Mahajan, 2014). The physiological effect of relaxation in reducing the activity of the sympathetic nervous system and consequently, reducing plasma cortisol, improves blood glucose level (Seidi et al, 2016).
Systolic blood pressure
The mean score of systolic blood pressure before and after the intervention in the groups was statistically significant (P<0.001), indicating a reduction of systolic blood pressure in the intervention group. During pregnancy, the circulation system undergoes significant physiological adaptations, whereby the arterial blood pressure decreases and reaches its lowest level in the 24-26 week period and then increases. During the study, the systolic blood pressure was expected to rise due to the increase of gestational age. This was observed in the control group (mean +6.76 mmHg), but in the intervention group it decreased.
Previous studies have reported the effect of stress and relaxtion on blood pressure in pregnancy (Kaviani et al, 2014; Khani et al, 2014) also reported the effect of relaxation on the reduction of systolic blood pressure, while a review study by Chauhan and Sharma (2017) on the effect of advanced muscle relaxation exercises on blood pressure also showed a positive and beneficial effect of exercise on the reduction of blood pressure. Similarly, in a study by BasiriMoghadam et al (2014) on the effect of the Jacobson relaxation technique on blood pressure and dialysis adequacy in patients undergoing haemodialysis, relaxation reduced blood pressure and increased dialysis adequacy. Azimian et al (2017) studied the effect of relaxation and mental imagery on hypertension in pregnancy and found a significant reduction in systolic and diastolic blood pressure. Relaxation exercises increase the secretion of endorphins and decrease the secretion of adrenaline hormone, cortisol levels, and heart rate and blood pressure in pregnant women (Rahimi et al, 2014). These exercises can also reduce blood pressure and pulse by muscle relaxation, reducing vascular resistance and sympathetic activity, and controlling breathing. However, in a study by Fink (2012) on the effect of relaxation and mental imagery on the cardiovascular function of pregnant women, no change in systolic blood pressure was observed. In explaining this contradiction, Fink et al (2012) used a quick relaxation exercises in each session, which differed from the technique used in this study.
Diastolic blood pressure
The mean diastolic blood pressure after the intervention in both groups was not statistically significant (P=0.151), indicating that by performing relaxation techniques, diastolic blood pressure showed limited reduction in the control group (-2.76 mmHg) and in the intervention group (-1 mmHg). In the first half of pregnancy, diastolic pressure is reduced due to the dilation of the peripheral vasculatures, which returns to normal during the third trimester. No changes were reported in diastolic blood pressure in the control and intervention groups in studies by Fink et al (2012) or Kaviani et al (2014). Similarly, Jafarnejad et al (2016) found that respiratory control exercises for gestational hypertension showed a greater reduction in systolic pressure than diastolic pressure. In a further study, Abedi Amiri et al (2018) examined the effect of 6 weeks of pranayama breathing exercises on serum cortisol levels and blood pressure in pregnant women in the third trimester of pregnancy. Serum cortisol levels and diastolic blood pressure were found to be reduced, but systolic blood pressure did not show statistically significant changes. This contradiction may be due to different ways of relaxation, and the time and duration of the intervention.
Conclusion
This study has reported the positive effect of relaxation exercises on the reduction of fasting blood glucose levels and systolic blood pressure in women with gestational diabetes. Considering the impact of gestational diabetes on maternal and fetal health, and as there is less emphasis on investigating women's mental health, a comprehensive relaxation exercise programme can be devised to reduce the risks of gestational diabetes by reducing stress.
Limitations
The particular life habits, cultural backgrounds, interests, and motivations of the samples may have impacted the implementation of the intervention, which were factors beyond the researcher's control.