www.jainworld.com                PREKSHA         By Swami  Darmanand ji

 

RESEARCH STUDY OF REVERSAL OF CORONARY HEART DISEASE THROUGH PREKSHA MEDITATION WITH REFRENCE TO -

CORONARY ATHEROSCLEROTIC REVERSAL POTENTIAL OF YOGA LIFE STYLE INTERVENTION

S.C.Manchanda MD. R. Narang MD, K.S. Reddy MD, U Sachdeva MD,  D. Prabhakaran MD, S. Dharmananda BA, M. Rajani MD, R.L. Bijalani MD.

Abstract

Background: It is not clear if lifestyle modification has any role in control of symptoms, progression of coronary lesions and prognosis in patients with advanced obstructive coronary artery disease.

Methods: In the prospective, randomised, controlled trial, 42 men with angiographically proven coronary obstructive disease were randomized to control (n=21) and yoga intervention group (n=21) and were followed for 1 year. The yoga lifestyle programme was a user friendly program consisting of strict control of risk factors, diet control (15% calories from fat, mostly mono-and polyunsaturated 65% from carbohydrate, mostly complex, 20% from proteins, high fiber (> 50 g/day) and antioxidants), moderate aerobic physical exercise, health rejuvenating exercises, breathing and relaxation exercises, stress management, meditation and reflection on moral values. The patients were taught various yogic exercises at yoga centre which they later practiced everyday at home. The control group was managed by conventional methods, i.e. risk factors control and AHA step I diet.

Results: At the end of 1 year, the yoga groups showed significant improvement in number of anginal episodes, improved exercise capacity and decrease in body weight, and total and LDL cholesterol and serum triglyceride levels as compared to controls. Coronary angiography repeated at 1 year showed that significantly more lesions regressed (20% versus 2% and less lesion progressed (5% versus 37%) in the yoga group (chi-square = 24.9; P<0.0001). Revascularisation procedures (coronary angioplasty or bypass surgery) were much less frequent in the yoga group (1 versus 8 patients; relative risk 5.45; P=0.01) The compliance of the total programme was excellent and no side effects were observed.

Conclusions: Yoga lifestyle intervention is beneficial in improving the symptoms and exercise capacity, lowering weight and serum lipid levels. It also retards the progression of coronary atherosclerosis in-patients with severe coronary artery diseases and reduces revasularisation procedures.

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Introductions

A number of studies have documented that a change in lifestyle (chiefly consisting of dietary modifications, physical exercises and stress relaxation techniques) results in reduction of cardiac events in patients with coronary artery disease (CAD). However, there is a paucity of studies to determine whether lifestyle modification can result in regression of the coronary atherosclerotic plaques. Ornish et al observed a regression of coronary aterosclerotic obstruction by strict lifestyle intervention. However the coronary stenoses were mild (40% and 43% diameter stenosis in treatment and control groups. Respectively) and the diet prescribed in their study was also very stringent. With only 5mg of cholesterol allowed per day. It is likely that such strict control of diet may not be practical for most patients.

 

The present study was designed to assess the effects of strict but "user friendly" intervention using yoga lifestyle methods (with strict control of risk factors) on the angioraphic severity of atherosclerotic obstructions in patients with advanced CAD (>70% luminal diameter stenosis in at least 1 vessel). The effects on symptoms, exercise capacity serum lipids and cardiovascular events were also analyzed.

Aims & objectives

The objective of this study was to determine whether a user-friendly yogic lifestyle intervention program (including yogic exercises, dietary management, moderate aerobic exercise and stress management) with control of other risk factors can reverse the atherosclerotic obstructions in patients known to have coronary artery disease.

Material and Methods

Forty-two male patients (mean age 51.0 + 9.5 range 32-72 years) with angiographically proven CAD were included in this prospective, randomized, controlled trial. At baseline detailed clinical assessment, serum lipid profile, treadmill exercise testing using modified Bruce protocol and coronary arteriography were performed.

Patients in the control group (n=21) were managed on conventional medical therapy (with control of risk factors, AHA step 1 diet, moderate aerobic exertion), while those in the yoga group (n=21) were advised strict lifestyle modifications and yogic exercises as detailed below. The medications for angina were continued. No patient was receiving lipid-lowering drugs. The patients were

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followed for 1 year with regular assessments. At the end of 1 year, the patients

again underwent detailed clinical assessment, serum lipid profile, treadmill exercise test and repeat coronary arteriography. Coronary arteriography was analyzed quantitatively using the caliper method. All arteriograms were analyzed by two independent blinded observers. For coronary angiography the effect on individual lesions was compared in the 2 groups. Ethical clearance was obtained from the institutional ethics committee and all patients gave informed consent to take part in the study.

 The baseline characteristics of the patient population are detailed in table 1. Most patients were in NYHA functional class II(52% patients) or class III                 (41% patients). The patients in both groups had elevated mean total and low-density lipoprotein cholesterol. The study was conducted before the results of major trials of statins in coronary artery disease were published and none of the patients were on lipid lowering therapy. All patients had at least 1 mm ST segment depression during exercise testing. Coronary arteriography showed majority (81%) of patients to be have triple vessel disease.

Yoga lifestyle intervention program

After inclusion in the yoga group, patients, alongwith their spouses, spent 4 days at a yoga residential centre, where they underwent training in various yogic lifestyle techniques. The yogic lifestyle intervention program consisted of:

        Yogic lifestyle methods

1.      Health rejuvenating exercises: a set of movements for improving the general tone of the body and to improve coordination.

2.      Relaxation exercise (Kayotsarg): a method of complete relaxation to prepare the body and mind for meditation.

3.      Breathing exercises (Pranayama)

4.      Yogic postures for stretch relaxation (Asanas)

5.      Preksha meditation (Preksha means seeing deeply within)

6.      Reflection on moral values (Anuvrat and Anupreksha)

 

        Stress management (relaxation, breathing exercises and Preksha meditation)

        Dietary control.

        Moderate aerobic exercises.

 

Patients visited the yoga centre every fortnight for monitoring and evaluation. The compliance as reported by patients themselves and by spouse, was recorded. In addition, the patients were followed every month in cardiac clinic of the hospital for clinical examination and investigations.

Dietary Control

Patient were advised take a low fat (mostly poly-or monounsaturated,

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providing15%of calories), low cholesterol (<50 mg/d), high carbohydrate (mostly complex, providing 65% of calories) diet. Patients were also encouraged to have high soluble fiber diets (>50gm/d) consisting of vegetable and fruits, oat bran, soybeans, gram and other beans, They were also prescribed 15gm psyllium husk (almost entirely fiber) daily. In addition, the diet advised was rich in antioxidants (carrots for beta-carotene, fruits, for vitamin C, nuts like almonds and walnuts for vitamin E and flavonoids from onions, coloured fruits and vegetables). Illustrative recipes and menus with known nutritional values were provided to avoid monotony.

The compliance of patients was assessed in a quantitative manner using a standard questionnaire and the score could range from 0 to 100.

Statistical Analysis       

All data are presented a mean � SD unless stated otherwise. The results at the end of 1year were compared with those at the baseline. The changes in the yoga group were compared with those in the control group. The P values were calculated using student's t-test for paired data. Chi-square analysis using Yate's correction was performed wherever appropriate.

Results

Both groups were similar at baseline with respect to mean age, weight, serum lipid profile, and mean lesion severity (Table1). However, patients in yoga group had significantly more.

TABLE 1. Baseline characterics of yoga and control groups

Parameter

Yoga group

Control group

P values(Yoga Vs Control

Age (years)

51�9

52�10

Ns

Hypertensive

43%

38%

Ns

Diabetic

29%

24%

Ns

Smokers

19%

24%

Ns

Previous MI

33%

29%

Ns

Previous CABG

10%

5%

Ns

NYHA functional class

2.62�0.67

2.33�0.58

Ns

Anginal episodes/Wk

6.71�2.95

4.10�2.14

0.002

Weight

72.1�12.5

72.81�9.84

Ns

Total Cholesterol

257�43.6

236.86�40

Ns

LDL Cholesterol

156�32.7

145�30.5

Ns

HDL Cholesterol

40.81�6.25

38.81�4.34

Ns

Triglycerides

193�58.1

169�47.13

Ns

LDL/HDL ratio

3.84�0.89

3.78�0.87

Ns

Exercise Duration

349�147

430�19.29

0.056

**Double Product achieved (*10 )

23.62�2.66

24.13�2.41

Ns

ST segment depression during exercise test

2.62�0.62

2.23�0.53

0.044

Mean Lesion Severity

62.4�14.5

59.7�17.7

Ns

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Ns = Not Significant

* All patients were men

** Product of heart rate and systolic blood pressure

Table II Parameters at baseline and at 1 year in the yoga and control groups.

 

Parameter

Yoga group

Control group

 P values*

 

Baseline

After

1 years

Change at 1 year

% Change

P (before   VS after)

Baseline

After 1 year

Change at

 1 year

% change

P(before vs after)

Change at 1 year

NYHA functional class

2.62�0.67

1.43�0.6

-119�51

-46�15%

<0.0001

2.33�0.53

2.86�0.75

0.52�0.75

29�37%

0.004

.0001

Anginal

6.71 � 2.95

2.14�2.65

-4.57�2.36

-73.2�2.27%

<0.0001

4.10�2.14

5.38�2.29

1.29�2.15

47�67%

0.01

.0001

Episodes/wk

 

 

 

 

 

 

 

 

 

 

 

Weight

72.1�12.5

66.5�8.3

-5.62�7.2

-6.8�8.2%

0.0019

72.81� 9.84

72.4�9.65

-0.38�3.35

0�5%

0.61

0.0005

Total Cholesterol

257�43.6

203�33.9

-54.14�36

-20.2�6.12%

<0.0001

236.86�40

236�35.1

-1.29�17.5

0�8%

0.74

.0001

LDL Cholesterol

156�32.7

118�29.8

-38.1�33

-23.2�17%

0.00004

145�30.5

142�27.17

-3.29�16.83

-2�12%

0.38

0.0002

HDL Cholesterol

40.81�6.25

41.29�4.47

0.48�5.6

2.8�14.9%

0.70

38.81�4.34

39.8�5.99

0.95�4.41

3�12%

0.33

0.76

Triglycerides

193�53.1

148�49.9

-45.7�66

-20.1�26%

0.005

169�47.13

174�51.06

4.76�27.33

3�17%

0.43

0.003

LDL/HDL ratio

3.84 �0.89

2.81�0.66

-1.03�0.99

-24.3�22%

0.0001

3.78�0.87

3.66�1

-0.11�0.53

4�13%

0.33

0.0008

Exercise Duration

3.49�147

413�132

63.8�73.7

28.0�44.7%

0.0008

430�119.29

374�150.86

-56.67�117

-17�23%

0.055

0.0007

Double Product Achieved(*10)

23.62�2.66

23.79�2.75

0.17�2.08

1.0�8.5

0.71

24.13�2.41

236�2.79

-57�148

-3�5%

0.12

0.14

ST segment Depression during exercise test

2.62�0.62

1.80�0.82

0.82�0.59

-32.0�25%

0.0001

2.23�0.53

2.67�0.56

044�0.62

27�49%

0.008

.0001

Mean lesion Severity

62.4�14.5

60.9�16

-1.5�9.7

-1.5�17%

0.23

59.7�17.7

68.4�16

8.7�12.9

26.5�80%

<0001

<0.0001

* Yoga vs control group

anginal episodes per week (6.7�3 vs 41�2.1) On treadmill testing also. These patients could exercise for shorter duration (349�147 vs 430�119 seconds P=0.056) and had more ST segment depression (2.6�0.6 vs 2.2�0.05 mm P=0.04)

The compliance score varied from 50 to 95% (mean 79.5�14.5%) Sixty seven percent patients had a compliance score of 80% ore more. The results on various outcome variables are summarized in Table II.

 Clinical Profile

Patients in the yoga group showed an improvement in the NYHA functional class while patients in the control group showed an overall worsening (p<0.0001). The number of episodes of angina per week reduced by 73% in the yoga group. While they increased by 47% in the control group (Table II).

The body weight showed a small but statistically significant decrease (7% P= 0.002) in the yoga group while the control group which did not show any significant alteration. The lipid profile showed significant reduction in the level of total and LDL cholesterol as well as triglycerides in the yoga group (about 20% reduction in each of these table II) while these parameters showed no significant change in the control group. Though there these was no beneficial effect on the HDL levels. The atherogenic ratio (total/HDL cholesterol) reduced significantly in the yoga group.

Stress test

There was an improvement in the exercise duration and a reduction in the degree of ST segment depression occurring during the stress test in the yoga group. On the other hand patients in the control group showed a reduction in the exercise duration and an increase in the ST segment depression occurring during exercise (P=0.0007 and 0.0001 respectively).

Coronary Angiography

Coronary arteriography was repeated at 1 year in all patients. A total of 120 lesions were analyzed (61 in the yoga group and 59 in the control group) At baseline there was no significant difference in the mean severity of lesions in the two groups (62.4% vs 59.7% diameter stenosis). At 1 year there was progression of coronary stenosis in the control group (mean worsening of 9+13% diameter stenosis) whereas the yoga group showed no significant change. This difference was highly significant (P< 0.0001).

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The change in the lesion severity was classified into regression ( 10% absolute reduction in diameter stenosis) no significant change (< 10% change in diameter stenosis) or progression (> 10% absolute increase in diameter stenosis) In the  yoga group, 3 lesion showed progression 46 lesion showed no change while 12 lesion showed regression. In the control group 22 lesions showed progression 36 showed no change while 1 showed regression (Fig.1). This difference was highly significant  (chi-square 24.5. P< 0.0001).

Revascularisation procedures

Coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA) were markedly reduced in the yoga group as compared to controls. Only one patient in the yoga group needed revascularisation (PTCA) as against 8 in the control group (2 PTCA and 6 CABG) (relative risk 5.45: P=0.01).

Discussion

There are number of reports of a favourable effect of risk factor modification in patients with coronary artery disease (secondary prophylaxis) Ornish et al (1983) reported the short-term effects of stress management and dietary changes in patients with coronary artery diseases. In this study of 46 patients (23 of whom received this intervention), there was 44% mean increase exercise duration, 55% mean increase in total work performed and improved regional wall motion during peak exercise. These changes occurred at a mean of only 24 days of intervention. There was a remarkable 91% reduction in the frequency of anginal episodes. The mean reduction in plasma cholesterol levels was 21%.

Subsequently in the lifestyle Heart Trial ornishet al (1990) studied the effect of comprehensive lifestyle changes (low fat vegetarian diet, stress management training moderate exercise and stopping smoking) on the severity of CAD determined by quantitative coronary arteriography. After 1 year of follow up analysis of 195 lesions in 48 patients (28 in the active group) shoed that the average diameter stenosis regressed in the active group (from 40+17% to 37.8 +16.5%) while it progressed in the control group (from 42.1�15.5% to 46.1�18.5) overall 82% of active group patients had an average change towards regression. It was concluded that comprehensive lifestyle changes can produce regression of obstructive coronary artery disease after only one year, without the use of lipid -lowering agents. Gould et al (1992) from the same group subsequently showed that complex shape changes and stenoses moudling characteristics occur over a period of time. Such changes result in an overall regression of the severity of lesions with improved stenosis flow reserve with intensive lifestyle modifications, while these changes result in overall progression of stenosis severity and worsening flow reserve in the control group.

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In a recent study. Gould al (1995) showed that such risk factor modification also results in a decrease in the size and severity perfusion abnormalities on rest dipyridamole position emission topography (PET) reflecting an improvement in the integrated flow capacity of the entire coronary arterial circulation. The size and severity of abnormalities increased in the control group over 5 year study period.

Studies from Heidelbey have also demonstrated the benefical effects of comperehensive lifestyle changes (including diet and physical exercise) on the coronary anatomy in-patients with CAD. Lipid lowering agent were not prescribed. After 1 year, the intervention group showed progression in 23% and regression in 32% patients, compared with 48% and 17% respectively in the control group (P<0.05). The benefit persisted at 6 years of follow-up (P<. 0001). A multivariate analysis identified only physical work capacity as independently contributing to angiographic changes.

Effects of comprehensive program of risk reduction involving both changes in lifestyle and medication were evaluated in the Stanford Coronary
Risk Intervention Project (SCRIP) 15. Again the risk reduction group showed a 47% reduced progression of coronary artery segments as compared with the usual care group (P<. 02).

The results of our study are consistent with those of the above mentioned studies. Yoga lifestyle intervention was found to have several beneficial effect in-patients with coronary artery disease, even when the disease was advanced. It markedly improved symptoms of angina and the exercise capacity of these individuals. It also reduced the body weight & favorably attired the lipid level.  It also reduced total and low density lipid cholesterol as well as serum triglyceride levels, though the HDL cholesterol was not significantly affected Coronary angiography showed retardation of progression of the disease as well as regression of significantly more lesions as compared to the control treatment. The revasculanzation procedures were significantly less in the yoga lifestyle group, though the numbers were small. This may be related to " stabilization" of the atheromatous plaques similar to that thought to occur following statin therapy.

The main advantage of our program was that it was much more "user friendly" than the interventions used in previous studies such as those by Ornish and Gould. The dietary modification in our study was also more liberal as 15% of energy from fats and 50 mg of cholesterol per day were allowed as compared with 10% energy from fats and only 5 mg of cholesterol per day in the study by Ornish et al. The patients included in our study also had significantly more severe disease (81% had triple vessel disease). Many of these patients had earlier declined to undergo revascularisation procedures. Moreover ours is perhaps the only study which assessed the effects of yoga lifestyle intervention on the angiographic severity in-patients with advanced CAD.

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 Limitations of the study

We recognize several limitation of this study

1.      Relatively small number of patients have been studied. Though the result are encouraging the need to be replicated in larger number of patients.

2.      The patients in the yoga group had more rigorous follow-up though the control group was also followed regularly.

3.      By nature of the interventions involved the study could not be blinded and hence a placebo effect of yoga intervention cannot be excluded. However the coronary angiograms were interpreted by blinded observers.

4.      The compliance of diet and yoga exercises was monitored from the reports of patients themselves and was not directly observed by the investigators. However the spouses of the patients in yoga were also involved and they also monitored te compliance of patients.

5.      The luminal diameter stenosis was measured quantitatively by caliper method and not by automatic edge detection techniques using dedicated software systems. However, the caliper method has been used widely in angiographic studies.

6.      The differential effects of yogic exercise dietary control and aerobic exercises were not assessed. We considered yoga lifestyle modification program as a composite intervention incorporating all the above mentioned components.

 However despite above limitations, outcome variables in the two groups are significantly different and are likely to be clinically important.

Conclusions

The study shows that yoga lifestyle intervention program is possible to carry out in-patients with advanced coronary artery disease with a high degree of compliance. It has favorable effect on angina, body weight, lipid levels, exercise stress testing with retardation of progression of coronary obstruction as compared with control group. Yoga lifestyle appears to stabilize the                      atherosclerotic plaques thus decreasing the need for revascularisation procedures. Hence, yoga lifestyle is a feasible and cost-effective intervention in-patients with advanced coronary artery disease.

 Acknowledgement

We are grateful to Swami Dharmanada for imparting the yoga training to the participants of this study and for supervising their progress. The study was supported in part by a grant from the Council of Yoga and Naturopathy, Ministry of Health, Government of India.

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APPENDIX

Outline of yogic exercises that formed part of yoga lifestyle modification program.

A.     Health Rejuvenating Exercise: These exercises are aimed mainly at improving the general tone and flexibility of various parts of body. These were also performed during warming up and to prepare for the next step, i.e. the asanas.

B.     Asanas: These are the yogic postures and exercises mainly aimed at stretch relaxation. A number of asanas were taught including Surya namaskar, Tadasana, padshasta asana, Vajrasana, Shasank asana, ardha-matsyendrasana, Paschimottantasana, Bhujangasana, Dhanush ban asana, Shalabhasana, Uttanpadasana, Merudandasana, Pawan Muktasana, Sarwangasana, Matsyasana, Ardhamatsyasana and Pranayam.The detaisl of these asanas can be found in any book on yogic exercise.

C.    Kayotsarga: A method of complete relaxation and preparation of body and mind for meditation. The literal meaning of Kayotsarga is to drop the body. In practice it is the conscious suspension of all movements of the body. As a result the muscle relax and the person becomes as restful as in sleep.

D.    Preksha Dhyan: Preksha means perception and Dhyan means concentration. Preksha Dhyan is performed in the sitting position and person first relaxes the body using Kayotsarga. He then concentrates on the breath and gradually and consciously reduces the rate of breathing from 15-17/ minute to 10-12/ minute. With practice, the rate may be reduced even to 4-6/ minute. By concentrating on the breath, the mental activity is controlled and the mind is prevented from being distracted.

E.     Anuvrat and Anupreksha: Anupreksha means contemplation or reflection or thoughtful consideration. Anuvrat is concerned with moral values, which would include consideration for others, unity of mankind, communal harmony, non-violence, limitation of acquisition and consumption, integrity in behavior and purity of means.

 

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