Reduction of PTSD in South African University Students Using Transcendental Meditation Practice

Abstract

A study was conducted on South African college students using the Transcendental Meditation technique to reduce posttraumatic stress disorder. Students meeting the criteria for possible posttraumatic stress disorder were included. Thirty-four students at the experimental university in South Africa clinically diagnosed with posttraumatic stress disorder were instructed in and practiced the Transcendental Meditation technique twice daily compared to 34 diagnosed posttraumatic stress disorder comparison students at the comparison university. The multivariate effect was significant for both the posttraumatic stress disorder symptomatology and depression. Results were significantly associated with regularity of practice. The study replicates recent findings and offers an alternative educational treatment for higher education.

Keywords

PTSD post-traumatic stress disorder mental health education university school psychology psychiatry meditation Transcendental Meditation trauma stress violence sexual abuse war

Introduction

The need

Several studies have suggested that adolescents and children in South Africa are exposed to relatively high levels of traumatic experiences, particularly witnessing or experiencing violence of a criminal or domestic nature, associated in turn with estimates of posttraumatic stress disorder (PTSD) ranging from 8% to 38% (Ensink, Robertson, Zissis, & Leger, 1997; Peltzer, 1999; Seedat, van Nood, Vythilingum, Stein, & Kaminer, 2000; Suliman, Kaminer, Seedat, & Stein, 2005). Similarly, a large majority of South African mothers reported lifetime trauma exposure, and this group had a 20% chance of PTSD in their lifetime (Koen et al., 2017). These lifetime rates were 24% in a Zulu-speaking group within South Africa and rose when language was taken more fully into account (Madigoe, Burns, Zhang, & Subramaney, 2017). South Africa is noted for a high level of sexual assault (Wyatt et al., 2017), with PTSD and depression as consequents. This research agues for a way, potentially widespread, to alleviate PTS and depressive symptoms without assuming a network of counselors.

Transcendental Meditation

This study examined the effect of a specific meditation procedure, the Transcendental Meditation® (TM®) program, in reducing symptoms of PTSD among students beginning their postsecondary education in South Africa. The TM® technique is described as an easily learned procedure that enables the mind to settle to a state of inner calm traditionally described as “pure consciousness” (Maharishi Mahesh Yogi, 1967/2011). This practice is learned over four consecutive days (about 90 minutes per day) in a course that is standardized internationally. This procedure has been shown to elicit a unique state of restful alertness reflected both in basic autonomic and biochemical measures of the physiology (Walton et al., 2002) as well as electroencephalographic and magnetoencephalographic measures of brain activity (Travis & Arenander, 2006; Travis et al., 2010; Yamamoto, Kitamura, Yamada, Nakashima, & Kuroda, 2006).

Note that the physiological and biochemical effect of the TM technique are in the opposite direction of the effects of acute stress, indicating deactivation of the hypothalamic–pituitary–adrenal axis. For example, a randomized clinical trial found a lower basal level of plasma cortisol after four months in a group assigned to learn TM compared to those taking a stress education course (MacLean et al., 1997). Also, this study reported lower cortisol response to stress longitudinally as an effect of learning the TM technique (MacLean et al., 1997). In this study, the cortisol response to stress, in contrast to the chronic response characteristic of PTSD in which there is greater cortisol reactivity but inefficient return to baseline, was a large immediate cortisol response to laboratory stress after learning the TM technique, after which time cortisol quickly returned to a lower than normal baseline, so that the overall average cortisol level was significantly lower (MacLean et al., 1997).

This experience has been found to alleviate substantially the physiological and psychological effects of stress. For example, a meta-analysis of randomized controlled trials found effect sizes between −.43 and −.50 in comparison to active alternative treatments (Orme-Johnson & Barnes, 2014). The TM program has been found to be similarly effective in comparison to other active programs in reducing recidivism among a maximum-security population upon release, a population subjected to great stress (Alexander, Rainforth, Frank, Grant, von Stade, & Walton, 2008; Bleick & Abrams, 1987; Rainforth, Alexander, & Cavanaugh, 2008). The predicted influence of this restful alertness state of mind and body in relieving severe stress forms the theoretical foundation of this study.

TM and PTSD

Among Vietnam war veterans, a small randomized clinical trial indicated that TM significantly reduced posttraumatic stress (PTS) symptoms, as well as anxiety, depression, emotional numbness, family problems, physiological stress reactivity, insomnia, and alcohol use after three months, in contrast to a psychotherapy control group (Brooks & Scarano, 1985). Rosenthal, Grosswald, Ross, and Rosenthal (2011), in a small-sample case study, also found reductions in PTS symptoms, depression, and anxiety among veterans of the Iraq war who began the practice. A recent longitudinal study found that among military veterans diagnosed either with PTSD or with anxiety disorder not otherwise specified, those who learned TM displayed stabilized, decreased, or cessation of medication compared to matched controls, significantly so at one and three months, and significantly reduced severity of psychological symptoms after one month (Barnes, Monto, Willliams, & Rigg, 2016). Thus, PTS symptoms and the comorbid symptom of depression warrant further study.

Congolese refugees in Uganda also reported clinically significant reduction of PTS symptoms (to nonsymptomatic levels, as defined below) 30 and 135 days after learning the TM technique in contrast to matched controls who showed no change (Rees, Travis, Shapiro, & Chant, 2013). When the control students began the practice, they showed a highly significant decline in symptoms as early as 10 days after instruction (Rees, Travis, Shapiro, & Chant, 2014) and approached the nonsymptomatic level by 30 days.

The study reported here extends this research for the first time to a youthful but underserved population of higher education students. It tests the hypothesis that regular practice of the TM technique by students clinically diagnosed with PTSD, in contrast to comparison students, would lead to a significant reduction in PTS symptoms, and in depression, within a relatively short time frame that would be maintained or even continued over time.

Method

Prior to the primary study itself, a pilot study was performed to assess whether effects of the TM technique on PTS symptoms would be measurable in a sample of South African students who learned the technique as part of their postsecondary education at the experimental institution in Johannesburg, South Africa. (All students there learn the TM technique as part of their curriculum.) This research may be understood as evaluating the existing curriculum of the experimental institution in Johannesburg, which precluded the possibility of random assignment to groups as well as precluding the use of another sample of that institution’s students as controls. This study and the original pilot study received institutional review board approval from that institution.

The single-sample pilot study indicated a reduction of PTS symptoms and motivated the primary study reported here, on a subsequent class of incoming students at the experimental institution, as well as a comparison group of new students from the comparison institution. The pilot data indicated that a sample size of 15 per group would provide customarily adequate statistical power in this study. This study utilized a clinician confirmation of PTSD diagnosis according to Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) criteria, measurement of depression comorbidity, and measurement of regularity of meditation practice. Because this research, in its pilot phase, was begun in early 2013 before DSM-5 was published, DSM-IV criteria were maintained throughout, despite an update of the PTSD Checklist—Civilian (PCL-C; Weathers et al., 2013).

Participants

The first-year class at the experimental institution participated in the study, as well as participants in business and communications classes at the comparison institution. Volunteers comprised 178 potential experimental students, and 352 potential comparison students. All participants signed an informed consent form. One hundred sixteen potential experimental students, 45 males and 71 females, met the minimal PCL-C score (44 and above) for inclusion to the treatment group (McDonald & Calhoun, 2010; Weathers, Litz, Huska, & Keane, 1994.) Sixty-one volunteers, 18 males and 43 females, who met the PCL-C criterion, were potential comparison group members and were given the option to learn the TM technique after the study. Three students took advantage of this offer after the study was over. The two institutions draw on students who are demographically comparable. All potential participants with a PCL-C score of 44 and above were then evaluated by a trained clinician using the criteria of DSM-IV for diagnosis, with a separate clinician for each institution. Thirty-four participants from each of the two institutions met both the criteria for inclusion of a PCL-C score above 44 and a clinician’s diagnosis according to DSM-IV.

Instruments

PTSD Checklist—Civilian

The PCL-C (Weathers et al., 1994) and a trauma history questionnaire (described below) were used to screen for clinician diagnosis of PTSD. The sum of symptom scores was the primary PCL-C metric used in the study. Internal consistency of the PCL has been reported as .94 or above (Cronbach’s alpha), with test–retest reliability reported as ranging from .96 at two to three days and .88 at one week (Ruggiero, Del Ben, Scotti, & Rabalais, 2003). McDonald and Calhoun (2010) note that, although acceptable, heterogeneity of samples and research methods yield heterogeneity of specificity, sensitivity, and other operating characteristics. PCL-C scores below 34 are considered nonsymptomatic (Weathers et al., 1994).

An alternative scoring approach for the PCL-C, in addition to the sum of symptom scores, is to apply the DSM-IV criteria to the individual items. That is, because the PCL-C questionnaire was designed to mirror the DSM-IV diagnostic criteria for PTSD, the questionnaire could be used to classify the students into those who may potentially meet the diagnostic criteria for PTSD and those who are unlikely to do so, according to the criteria given by Weathers, Litz, Herman, Huska, and Keane (1993). This is useful, as described below, as an alternative outcome criterion in the absence of a posttest clinician evaluation.

A simple trauma history questionnaire asked participants to report the number and approximate date of trauma in five major areas, including natural disasters, severe accidents, sexual and criminal victimization, and combat experiences. This test was used to determine that those with initial PCL-C scores over 44 also had a traumatic event associated with the high score, and this information was given to the clinical diagnostician for evaluation.

Beck Depression Inventory

In addition, the Beck Depression Inventory (BDI), a 21-item self-report measure widely used to assess depression in both clinical and normal populations, was included because depression is a substantial component of PTSD. The version used was IA, which has a coefficient alpha of .86 and one-week test–retest reliability ranging from .74 (Leigh & Tolbert, 2001) to .93 (Beck, Steer, & Brown, 1996).

Procedure

All participants from both the institutions were administered baseline measures, consisting of the BDI, PCL-C, and a brief trauma history inventory. Participants completed all questionnaires at one sitting in a large group at the experimental institution and by individual appointment at the comparison institution.

Potential participants who met the screening criteria were then interviewed by a licensed South African clinician to determine if the diagnosis of PTSD was warranted according to the criteria specified in DSM-IV. Those who received a PTSD diagnosis were participants in either the treatment or comparison groups of the study.

The students at the experimental institution then learned the TM technique, which was a part of their curriculum. Instruction in the TM technique is standardized worldwide, taught personally by certified instructors over four consecutive days (approximately 90 minutes per day), and instruction of all the participants in the study used this standard procedure. Participants were instructed to meditate at home (or at college on Monday–Friday) for 15 to 20 minutes twice daily, with weekly follow-up meetings with the instructors to remind students of correct practice and answer questions. The TM technique group then meditated together twice daily in a group on weekdays at the experimental institution and on their own on the weekend. Attendance at the group meditation sessions was recorded, and the number of weekend meditations was reported on a weekly basis.

The PCL-C was administered to both the treatment and comparison groups at 15, 60, and 105 days after pretest. The BDI was administered to both groups at 60 and 105 days posttreatment and to the experimental group alone at 15 days after pretest.

Results

Statistical analysis

Data were analyzed by multivariate analysis of covariance (MANCOVA). Although the alternate possibility was the use of repeated measures analysis of variance (ANOVA), the covariance matrix of the repeated measures was strongly inconsistent with the assumption of sphericity (χ²(9) = 213.48, p < .001 for PCL-C; χ²(5) = 115.62, p < .001 for BDI), indicating violation of a major assumption underlying the use of repeated measures ANOVA. It should be noted that the Doornik-Hansen test indicated that there was deviation from multivariate normality, a requirement for MANOVA (for the PCL-C, χ²(8) = 22.21, p < .01 among the experimental students and χ²(8) = 24.52, p < .01 among the comparison students; and for the BDI, χ2(6) = 16.87, p = .01 among the experimental students and χ²(6) = 23.19, p < .001 among the comparison students). However, MANOVA procedures are robust to violations of the assumption of multivariate normality, although sensitive to outliers. There were no observations (outliers) near 3.5 standard deviations from the mean in either group. Therefore, MANCOVA was determined to be more suitable as a statistical approach to the data than repeated measures ANOVA; in the case of MANCOVA, the covariance matrix was not assumed to conform to a particular structure. The analysis method therefore was MANCOVA where scores at sessions 2, 3, and 4 are considered dependent variables and session 1 (pretest or baseline) served as a covariate.

PCL-C scores

There was a significant difference on PCL-C score between the experimental and comparison groups at pretest with the comparison group having higher PCL-C symptomatology, F(1, 66) = 4.85, p = .031, η2 = .07, confirming the importance of the PCL-C baseline covariate in the MANCOVA. In terms of age and gender, there was no significant difference between the two samples (age: experimental M = 20.6 (SD = 2.75), comparison M = 21.1 (SD = 1.55), t(65) = 1.00, n.s., with age missing for one experimental student; gender: experimental group 27 women, 7 men, comparison group 21 women, 13 men, χ²(1) = 2.55, p = .11).

The multivariate test for the difference between the two groups over all the posttreatment time periods was highly significant, Wilks’ lambda = 0.36, F(3, 63) = 36.76, p < .0001, η² = .64. Of all the possible factors that could have affected the change in PCL-C scores over the 105-day period, group membership accounted for 64% of the variance.

The effect of TM practice was rapid (see Table 1). After 15 days of practice, the experimental group reported a mean of 39.1 on the PCL-C compared to a mean of 54.1 for the comparison group, F(1, 65) = 37.2, p < .0001, η² = .36, d = −1.48. After 60 days, the difference between the two groups was also significant, F(1, 65) = 50.5, p< .0001, η² = .44, d = −1.72. Likewise, the difference between the two groups in self-reported symptoms was still greater at 105 days, F(1, 65) = 113.0, p < .0001, η² = .63, d = −2.58, at which point the mean PCL-C score of the experimental group had reduced to a level considered nonsymptomatic (see Table 1).

Table 1.

	Condition	Baseline	15 Days	60 Days	105 Days
Test	Condition	Mean (SD)	Mean (SD)	Mean (SD)	Mean (SD)
PCL-C
TM (n=34)		53.3* (7.1)	39.1** (9.9)	36.2** (11.5)	32.0** (10.5)
Comparison (n=34)		57.0 (6.9)	54.1 (8.5)	55.9 (9.4)	56.9 (7.7)
BDI
TM (n=33)		19.9 (7.1)	9.5 (5.8)	9.2** (7.9)	7.4** (6.2)
Comparison (n=34)		16.9 (6.9)		16.3 (6.3)	17.3 (6.0)

Change in mean PCL-C score and BDI score by condition. PCL-C: Posttraumatic Stress Disorder Checklist—Civilian; TM: Transcendental Meditation; BDI: Beck Depression Inventory.

*p < .05; **p <.0001, TM group versus comparison group.

Due to cost constraints, there was no clinician diagnosis for PTSD at the 105-day assessment. However, as described in the “Methods” section, there was a dichotomous PCL-C measure of likelihood of clinical PTSD that was based on a minimum PCL-C score plus categorical assessment of PCL-C responses. A binary logistical regression analysis for the effect of TM practice 105 days after instruction on PTSD PCL-C diagnosis at using this assessment method was also highly significant, χ²(64) = 31.4, p < .0001, d = −1.85, with 7 likely PTSD and 27 unlikely for the experimental group and 30 likely and 4 unlikely for the comparison group.

BDI scores

Data for the BDI were similarly analyzed by means of a MANCOVA with BDI scores over the two common posttreatment times (60 and 105 days) as the predicted variables, and with treatment as the experimental factor and baseline BDI as covariate. There was one less experimental group participant in the BDI testing. The TM and comparison groups did not differ significantly in BDI score at baseline. The multivariate test for the difference between the two groups over all the posttreatment time periods was highly significant, Wilks’ lambda =.31, F(2, 62) = 70.5, p< .0001, η² = .69. BDI scores were significantly reduced for the TM students at both 60 and 105 days relative to comparison students, as listed in Table 1, F(1, 64) = 46.3, p < .0001, η² = .42, d = −1.66 and F(1,64) = 137.3, p < .0001, η² = .68, d = − 2.86, respectively.

Table 1 also notes the BDI score of the experimental group at 15 days after instruction in TM. For the TM group, mean BDI score dropped approximately in half in 15 days, from 19.9 to 9.5, a drop from high mild depression to normal levels. As can be seen from Table 1, the substantial decrease in depression for the TM group at 15 days was maintained at 60 and 105 days, while the control group was unchanged from baseline.

Depression and PTSD association

Pearson correlations were computed for the BDI and PCL at each testing time and these correlations grew significantly stronger over time, from r(160) = .26, p < .001 to r(99) = .54, p < .0001, to r(136) = .62, p < .0001, to r(134) = .69, p < .0001, respectively. Correlations for the treatment group alone were similar, suggesting that depression and PTSD were highly related and decreased together through the practice of the TM technique.

Missing data

Two students who completed baseline testing failed to complete subsequent testing because they dropped out of school. Statistical analyses were performed using the last scores available for all subsequent test administrations, assuming no subsequent change over time. The results of analyses were unchanged compared to those reported earlier that utilized only those students for whom complete data were available.

Regularity of TM practice

As predicted, regular TM practice was related to a greater reduction in PTSD symptoms. The TM technique treatment group (MI) meditated in a group twice daily on weekdays and attendance was recorded. These students reported the number of times they meditated alone on weekends. In general, the experimental students were consistent, regular meditators with a group average of 10.26 meditations per week (SD = 1.66) out of a total of 14 possible. Data on regularity were added as a covariate in the MANCOVA model to analyze both PCL and BDI data for those participants formally diagnosed with PTSD by a clinician; more frequent meditation practice was significantly related to the amount of reduction of stress responses as measured by the PCL-C with a multivariate Wilks’ lambda = 0.77, F(3, 29) = 2.9, p = .05, η²= .23. The between-student effects indicated that regular meditation was especially effective during the first 15 days of practice, F(1, 31) = 7.82, p = .009, η² = .20. The actual number of meditations was negatively correlated, r(36) = −.44, p < .007 with the PCL-C score after 15 days of TM practice, which was the predicted direction of the association. Average weekly practice of TM was also negatively correlated with depression at 105 days, r(34) = −.37, p = .03.

Discussion

Regular practice of the TM technique among experimental students was associated with significant and lasting reduction of PTSD symptoms and depression, with large effect sizes, and with the effect evident within 15 days. As predicted, regularity of meditation practice was directly related to the strength of the effect in the first 15 days, leading to a clearer inference that it was the TM practice per se that was responsible for the relief of PTSD symptoms.

Limitations

Several potential threats to validity were addressed and remedied. First, at pretest, the comparison group students had significantly higher PCL-C scores. This was accounted for statistically by covarying the pretest scores for both groups in the MANCOVA analysis. Second, two different clinicians diagnosed PTSD, one at each institution; but potential differences in clinician application of criteria should largely have been encompassed by the use of the pretest covariate.

The unusually large effect sizes need some explanation of the situational factors at the experimental institution that may have enhanced the study. There were no other self-development aspects of the experimental institution’s curriculum other than those that were studied here. Yet, one major factor is that an effort was made to ensure the regularity of practice of TM through twice-daily monitored group meditation. This strongly encouraged regularity of practice, supported that regularity with group interaction, and allowed relatively accurate measurement of regularity. The potential role of this strong regularity in contributing to the large effect sizes is consistent with the finding reported above that among treatment students, regularity of practice was related to degree of PTS symptom reduction. The similar results among Congolese refugees (Rees et al., 2013, 2014), and corresponding large effect sizes, suggest that the treatment schedule employed in this study as well as the Rees et al. (2013, 2014) studies might be taken as a guideline for best practice in such PTSD interventions.

However, it could be argued that the regular meditation checkup and daily group meditation created a placebo effect. The comparison group controlled for repeated testing, but did not control for the motivation of the participants. It could be argued that the experimental group decrease in PLC-C and BDI scores was due to this motivation effect rather than the experimental treatment. This is unlikely given that the effect of TM practice was maintained and strengthened after 105 days. That is, it is unlikely that PTSD symptoms would be affected by motivation, when they are usually resistant to treatment, but to be sure, an alternative method given equal treatment time will be necessary.

Another obvious limitation is the lack of randomization to the comparison group, which is necessitated by the fact that learning TM is a part of the experimental institution’s curriculum. In addition, the fact just noted that situational factors were controlled to optimize the regularity of TM could be taken as restricting the external validity of the findings to the experimental institution rather than to any educational or treatment center.

The study reported here was specific to a clinically diagnosed PTSD sample. Unlike the milder response to trauma that usually resolves spontaneously over time, clinical PTSD usually requires professional help. As noted earlier, South Africa has a high PTSD rate and insufficient opportunities for psychological treatment (Ensink et al., 1997; Peltzer, 1999; Seedat et al., 2000; Suliman et al., 2005). The college students with PTSD who practiced the TM technique daily (experimental group) had a highly significant reduction in stress symptoms within 15 days and were at PTSD nonsymptomatic levels by 105 days. Comorbid depressive symptoms also resolved for the TM technique group, falling into the normal range within 15 days of practice. Participants in the comparison group were essentially unchanged in both PTS and depression levels from the baseline measures. Neither group received any other treatment.

The effect sizes reported in this study are promisingly very large for diagnosed higher education students meditating regularly in a group and should be replicable under similar conditions. Large-scale randomized controlled trial studies are warranted to assess the effectiveness of the TM technique in such populations, as well as in older populations and those with complex PTSD and ongoing trauma, using clinician diagnosis of PTSD before and after the TM practice intervention as well as an alternative treatment.

The high incidence of PTSD among South African adolescents (Suliman et al., 2005) and the greater likelihood of multiple traumatic events leading to the development of more complex PTSD (Karam et al., 2014) suggest that late adolescence could be a critical time for intervention to improve both the individual and societal mental health. Where the number of professional mental health providers is insufficient, the TM technique may be especially valuable. This study showed rapid and highly significant reduction of symptoms maintained over time, with nonsymptomatic average scores within 3.5 months of TM technique instruction. The TM technique can be taught cost-effectively to large groups of higher education students in a systematic manner, and the results of this study suggest that group practice, easily arranged for educational institutions, can lead to high rates of compliance, thus effectiveness. This may be particularly relevant in countries where those of higher education age are subjected to multiple sources of stress.

Footnotes

Article Notes

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