TO STUDY AND CORRELATE THE EFFECT OF INTEGRATED APPROACH OF YOGA THERAPY ON FREQUENCY DOMAIN PARAMETERS AND POINCARE PLOT OF HEART RATE VARIABILITY AMONG PREDIABETICS

wasa nonlinear and geometricmethod to assess thenonlineardynamics of heart rate variability. 8 It is a plotin which each R-R interval was denoted as a function of the previous R-R interval where the values of each pair of subsequent R-R intervals representa point in the plot.Poincaré plots hadevaluated in a qualitative way using their visual pattern whereby the shape of the plot is categorized into functional classes that had a prognostic value incardiovascular disease and can be evaluated quantitatively through the computation of the Standard deviationindexes of the plot. 9 Hence Poincare plot analysis may be a better way to monitor the nonlineardynamic variationof autonomic functionafter the integrated approach of yogatherapy. 10 Genesis of HRV also involves the nonlinear phenomena, which are determined by complex interactions of hemodynamic, electrophysiological, and humoral variables, as well as by autonomic and central nervous regulations. Hence, the analysis of the nonlinear dynamics ofheart rate variabilitywould enable a better physiological interpretation of the variation in heart rate. 8 Poincare plot of RR intervals was animportantvisual tool, which wascapable ofanalyzingan entire RR time series derivedin one frame, and a quantitative technique which gives information onshort and long-termHRV. 11 Howeverstudies on the nonlinear component of HRV after the integrated approach of yoga therapywerenot well documented.Therefore, in this study, an attempt has been made to assessthe nonlinear dynamics of HRV byusing a Poincare plotafter an integrated approach of yoga therapyand comparing it with thatof the linear parameters. Using Poincare plot analysis may be a better way to assess dynamic changes of autonomic functions during meditation. sympathetic tone, and a more oval, fan-shaped configuration resulting from increased SD1/SD2 ratio represents decreased sympathetic tone. 5-7 In this study after six months of integrated approach of yoga therapy in Poincaré plots variables SD1 increases, the SD2 decreases, and SD1/SD2 ratio increases with a concurrent change of shape that wasat baseline shape was the narrower torpedo-like shapeand after six months of integrated approach of yoga therapyfan shape.Results of the present study are in concurrence to studies done by Karmakar CK et al 10 , Guzik P et al 11 .Inthis present study results ofcorrelation between spectral and Poincaré analysisshows LF/HFhas a positive correlation with the SD2/SD1 ratio. HF was positively correlated with SD1 &HF, SD2&LF results were similar with previous studies done by Bootsma M et al 19 , Silke B et al 20 , CarrascoS et al 21 Poincaré plot may identifyabnormalities that werenot easily detectable withfrequency domain measures. 20 Poincaré plot analysis of R-R intervals provides prognostic information in various cardiovascular diseases. The Poincaré plots which use the unfiltered data have theadvantage of being able to identify beat-to-beat cycles and patterns in the data. It has the advantage of being able to identify beat-to-beat cycles and patterns in the data. 11 Moreover, the Poincaré plot may be better in the use of dynamic analysis than spectral analysis. 21

Conventionally, there werelinear and nonlinear dynamics for assessment ofheart rate variability In linear dynamicstime and frequencydomain analysis in time domain using the various statistical measures and inthe frequency domain analysis using the spectral analysis by Fast Fourier transformation. However, time and frequency domain methods have got some technical limitationsand in some cases, these methods are insensitive and more susceptible to interference by ectopic rhythm. 6 In nonlinear dynamics, heart rate variability was assessed by Poincare plot and histogram.The analysis of Poincare plotsof RR intervals was an emerging method of nonlinear dynamics applied in HRV analysis. 7 The Poincare plot analysis wasa nonlinear and geometricmethod to assess thenonlineardynamics of heart rate variability. 8 It is a plotin which each R-R interval was denoted as a function of the previous R-R interval where the values of each pair of subsequent R-R intervals representa point in the plot.Poincaré plots hadevaluated in a qualitative way using their visual pattern whereby the shape of the plot is categorized into functional classes that had a prognostic value incardiovascular disease and can be evaluated quantitatively through the computation of the Standard deviationindexes of the plot. 9 Hence Poincare plot analysis may be a better way to monitor the nonlineardynamic variationof autonomic functionafter the integrated approach of yogatherapy. 10 Genesis of HRV also involves the nonlinear phenomena, which are determined by complex interactions of hemodynamic, electrophysiological, and humoral variables, as well as by autonomic and central nervous regulations. Hence, the analysis of the nonlinear dynamics ofheart rate variabilitywould enable a better physiological interpretation of the variation in heart rate. 8 Poincare plot of RR intervals was animportantvisual tool, which wascapable ofanalyzingan entire RR time series derivedin one frame, and a quantitative technique which gives information onshort and long-termHRV. 11 Howeverstudies on the nonlinear component of HRV after the integrated approach of yoga therapywerenot well documented.Therefore, in this study, an attempt has been made to assessthe nonlinear dynamics of HRV byusing a Poincare plotafter an integrated approach of yoga therapyand comparing it with thatof the linear parameters. Using Poincare plot analysis may be a better way to assess dynamic changes of autonomic functions during meditation.

Methods:-
The purpose of this study was to assess specifically the nonlinear dynamics of HRV using Poincare plotafter the integrated approach of yoga therapy and compare it with that of the frequency domainparameters ofHRV assessed by linear measures. The study was designed as across-sectional pilot study,conducted in a research yoga labat the department of physiology, RUHS College of Medical Sciences & Associated Hospitals., Jaipur.
The sample size wascalculated by using theformula z2pq/d2 where p & q were taken as .08 and .92 to get thesample size with 5% precisionand 10% non-response rate thesample size was 250 with a 95% confidence interval. 3 Subjects were divided into Group A and Group B. Group Awas control and Group B was a study group that engaged in an integrated approach of yoga therapy Participantsincludedhave Fasting bloodglucose level of110 to 125 mg/dL and Glycated hemoglobin 5.7 to 6.4 ( ADA criteria) 1 andno history of cardiovascular disease nohistory ofmedications. subjects whohave Fasting blood glucoseless than 100mg/dland greater than 126 mg/dl,Liver disease, renal dysfunction alcoholicindividuals, interstitial fibrotic disease, spinal injury, retinopathy & nephropathythose being treated with anti-inflammatory medication were excluded.
The Integrated Approachof Yoga Therapyincluded Prayer, Omkar recitation, yoga asanas, pranayama),Shavasana,Counselling, and dietary intervention. In dietary intervention, each participantreceived a diet plan from a qualified dietician as per dietary guidelines for Asian Indians. 12 In brief, guidelinesthe recommended nutrient composition for daily diet included50%-60% carbohydrates, less than 30% total fat, less than 10% saturated fat, 10%-15% monounsaturated fat, 5%-8% polyunsaturated fat, less than 200-300 mg cholesterol, 10%-15% protein, 25-40g dietary fiber, andless than 5g salt. subjects were instructed to record their daily food intake in a diary.Asanas and posture that included sukhasana, bhujangasana, suryanamaskar pashimottanasana,tadasana,padmasana,trikonasana,ardhmatsyendrasana,nsarvangasana,pawanmuktasana,vajrasana,d hanurasana,shavasana.Yoga asanas were supervised and demonstrated by certified yoga instructor .Yoga sessions were approximately 45 minutes six days per week for six months. To facilitate home practice, participants were given video clips of the yoga asanasrecorded under the direction ofthecertified yoga instructor,compliance of subjectswas checked bydailymessages on WhatsApp and weekly telephonic conversions withsubjects and familymembers. The evaluation wasdone baseline and after six months of integrated approach of yoga therapy. then after three andsixmonths of post-intervention. Afterobtaining ethical clearance fromthe institutional ethics committee. Participant information sheet andwritten informedconsent form were obtained.A detailed history was taken and a detailed general physical examination was conducted. Anthropometric measurements were taken andbaseline ECG was recorded for 5 minutes.

Analysis of heart rate variability-
The electrodes were placed on the pressure pad of the Finger Pulse Transducer. The HRV analysisin the frequency domain reflects the speed variation in heart rate. Further, this methodalso gives information about different frequency components of the N-N intervals and their power, or variance. ECG signals were recorded by a digital physiograph (AD instruments). The signals were filtered digitally and processed to extract QRS peaks which determine the R-R intervals. These QRS peaks were automatically detected and were reviewed visually for R-wave determination and ectopic beats. Areas of ECG in which identification of beats was poor or ectopic beats were present were excluded. The time and frequency domain indices were computed from 5-minute segments .

Frequency domain analysis:
Frequency domain analysis was done by power spectral analysis using fast Fourier transformation. The frequencydomain indices included low frequency (LF; 0.04-0.15 Hz), high frequency (HF; 0.15-0.4 Hz), e ratio of LF to HF (LF-HF ratio). 5 Nonlinear dynamics: assessed by Poincaré plot which is a graphicalrepresentationin which each R-R interval of tachogram is plotted against the previous R-R interval.It is a two-dimensional graphic representation of the correlation between consecutive RR intervals, in which each interval is plotted against the following interval and its analysis can be done qualitatively, by assessing the shape formed by its attractor, which shows the degree of complexity of RR intervals, or in a quantitative way. The quantitative analysis is done by fitting an ellipse to the shape formed by the plot and measuring the dispersion along the major and minor axis of the ellipse. 13,14 There are two standard descriptors of the Poincare plot namely: Standard deviation 1: The length of the transverse line is defined as the SD1 of the plot data in a perpendicular direction.It is the standard deviation (SD) of the instantaneous (short-term) beat-to-beat R-R interval variability (minor axis of the ellipse or SD1).
Standard deviation 2:The length of the longitudinal line is defined as the SD2 of the plot data.It is the SD of the long-term R-R interval variability (major axis of the ellipse or SD2). 13,14 Furthermore, additional parameters were computed which included:Area of the ellipse (S):It is given as the amount of area covered by the ellipse.It is calculated by doing the product of π, SD1, and SD2.It represents total HRV. 14 A normal configuration of the plot was defined as a fan of comet shape. Abnormal forms were a random pattern characterized by asymmetrical RR-interval clusters; a torpedo-shaped pattern with narrow configuration that lacked RR-interval dispersion .14 Statistical Analysis: Mean and standard deviations are calculated for each parameter. The appropriate tool for comparing the change in the level of a variable is the student's paired t-testfor Intragroup comparison before applying this test the Smirnov-Kolmogorov test is conducted to confirm the normality of each parameter. For all the variables normality is confirmed. The level of significance is taken at 5%. Tables are constructed to show the mean and standard deviation for the various parameters. Inference of significance is drawn on the value of p. Apart from comparing the various parameters of the data concerning before and after the integrated approach of yoga therapy, the comparison is made concerning a control group. There are 125 people in this group. To show that initially, the two groups are on the same platform for each parameter, the student's unpaired t-test is conducted for Intergroup comparison. If the value of p is more than 5%, for any parameter, that shows there is no significant difference between the two groups Results:-   Table 2 depicts that baseline parameter like body mass index, waist-hip ratio,blood pressure systolic and diastolic and pulse rate before and after the integrated approach of yoga therapy and results were aboutp-value significant.  In the control group, pre and post results were not significant whereas study group there was a significant reduction in, LF and (LF/HF ratio), SD2, and a significant increase in HF and SD1after six months of integrated approach of yoga therapy.    Results show there is a strong correlation b/w LF and SD2,HF and SD1, and LF/HF ratio and SD2/SD1.

Discussion:-
Studies on linear andnonlinear components ofheart rate variabilityare not well documented. Hence, in this study, an attempt has been made to assess and correlatelinearcomponents that were frequency domainand nonlinearcomponentlike poine care plot after the integrated approach of yoga therapy.
Thefrequency-domain parameters like the High-frequency component (HF) reflect parasympathetic activity, theLow-frequency component ( LF) reflects the sympathetic modulation, and LF/HF ratio indicates sympathovagal balance. 5 In thisstudy it was observed that in the spectral analysis, after the integrated approach of yoga therapy, which is show parasympathetic activity is stimulated after the integrated approach of yoga therapywith concomitant sympathetic withdrawal the outcome of the study has been found similar tostudies undertaken by Meshram  The Poincaré plot is a geometrical representation that allowstheidentification of the presence of non-linear HRV components. 8 In the Poincaré plots, the SD1 width reflects the parasympathetic activity; and the SD2 length reflects the sympathetic modulation. 10 The shape of the Poincaré plot can be used to visually evaluate the sympathovagalbalance. An elongated, torpedo-like shape with decreased SD1/SD2 ratio is denotesincreased sympathetic tone, and a more oval, fan-shaped configuration resulting from increased SD1/SD2 ratio represents decreased sympathetic tone. [5][6][7] In this study after six months of integrated approach of yoga therapy in Poincaré plots variables SD1 increases, the SD2 decreases, and SD1/SD2 ratio increases with a concurrent change of shape that wasat baseline shape was the narrower torpedo-like shapeand after six months of integrated approach of yoga therapyfan shape.Results of the present study are in concurrence to studies done by Karmakar 20 Poincaré plot analysis of R-R intervals provides prognostic information in various cardiovascular diseases. The Poincaré plots which use the unfiltered data have theadvantage of being able to identify beat-to-beat cycles and patterns in the data. It has the advantage of being able to identify beat-to-beat cycles and patterns in the data. 11 Moreover, the Poincaré plot may be better in the use of dynamic analysis than spectral analysis. 21 Hence, we assessedthat the findings of the nonlinear dynamics of HRV are corroborative with linear dynamics. It was able to summarize an entire RR time series derived from an ECG in one frame, and a quantitative technique, which gives information onshort and long-term HRV. 22 The advantage of nonlinear analysis wasthatnot require any preprocessing ofdata, which is needed in linear analysis. 24 Nonlinear methods such as the Poincaré plot, entropy analysis,detrended fluctuation analysis (DFA) & heart ratecomplexity analysis were newly developed tools used for identifying nonlinear patterns within electrocardiogram. 23 Limitationsof the study-Studies should be conducted in larger sample sizes and analysis bylogistic regression and multicentricto further establish the predictive and investigative importance of Poincare plot analysisand its predictive role in the assessment of cardiovascularrisks.

Conclusion:-
In the control group, pre and post results were not significant whereas study group there was a significant reduction in (LF/HF Ratio) after six months of integrated approach of yoga intervention. HF power spectrum showed an increasing trend inthe short-term practice of yoga. The decrease in LF/HF ratio in this study was likely to be predominated by sympathetic withdrawal and increasing parasympathetic activity. This study depicts the effect of the long-term practice of yoga can help in shifting the autonomic nervous system towards parasympathetic dominance.The Poincaré plot is visually more discernible to detect this autonomic change, showing the potential to evaluate the dynamic change associated withthe integrated approach of yoga therapy. For better dynamic monitoringthe Poincaré plot provides a qualitatively and quantitativelyvisual measure of sympathovagal activity.