High blood pressure and associated symptoms were reduced by massage therapy

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1 RESEARCH High blood pressure and associated symptoms were reduced by massage therapy... M. Hernandez-Reif,T. Field, J. Krasnegor, H. Theakston, Z. Hossain, I. Burman Abstract High blood pressure is associated with elevated anxiety, stress and stress hormones, hostility, depression and catecholamines. Massage therapy and progressive muscle relaxation were evaluated as treatments for reducing blood pressure and these associated symptoms. Adults who had been diagnosed as hypertensive received ten 30 min massage sessions over ve weeks or they were given progressive muscle relaxation instructions (control group). Sitting diastolic blood pressure decreased after the rst and last massage therapy sessions and reclining diastolic blood pressure decreased from the rst to the last day of the study. Although both groups reported less anxiety, only the massage therapy group reported less depression and hostility and showed decreased urinary and salivary stress hormone levels (cortisol). Massage therapy may be e ective in reducing diastolic blood pressure and symptoms associated with hypertension. Maria Hernandez-Reif PhD, Ti any Field PhD, Josh Krasnegor BA, Z. Hossain, HillaryTheakston BA, I. Burman LMT Research Institute, Universityof Miami School of Medicine and Nova Southeastern University, Florida, USA Correspondence to: Ti any Field, Touch Research Institutes, Nova Southeastern University, 330 College Avenue, Fort Lauderdale, FL 3334, USA. Tel.: ; Fax: Received: March 999 Revised: April 999 Accepted: May Journal of Bodywork and Movement Therapies (000) 4(), 3^38 # 000 Harcourt Publishers Ltd Introduction Hypertension, or high blood pressure, is a common health risk that can lead to heart disease, stroke, disability and death (France & Ditto 997). Blood pressure generally increases with age and is a ected by gender, cigarette smoking, obesity, diabetes, job stress, family history and other environmental and sociocultural factors (France & Ditto 997, Wright et al. 99). Patients with hypertension show greater anxiety, stress and depression (Walter et al. 995, Piccirilo et al. 998, Everson et al. 998), more anger and hostility, and more marked cardiovascular reactions to situational stressors (Ditto & France 990, Manuck). Cortisol (stress hormone) and catecholamine release (e.g. excess epinephrine); () have been shown to occur as acute responses to stress; () are typically associated with anxiety; (3) are positively correlated with blood pressure; and (4) have been shown to underlie myocardial damage and sudden cardiac death (Morse et al. 99, McCubbin, Walton et al. 995). Hostile and 3 JOURNALOFBODYWORKANDMOVEMENTTHERAPIES JANUARY 000

2 Hernandez-Reif et al. aggressive hypertensives, for example, show elevated plasma epinephrine (Netter & Neuhauser 99). In genetically inbred hypertensive rats, norepinephrine and dopamine uptake levels were enhanced compared to controls (Chivet et al. 984, Hendley & Fan 99). Thus, the reduction of catecholamines (i.e. norepinephrine, epinephrine and dopamine) and cortisol (stress hormone) should be an important goal in the treatment of hypertension. Recognizing that blood pressure is determined by multiple factors (catecholamine and cortisol levels, individual, interpersonal and environmental causes), complementary approaches may be needed to evaluate, prevent and treat hypertension (Sidorenko). Non-drug treatments, if e ective, can be less expensive and can avoid potential side-e ects (Khramelashvili 986) such as those associated with anti-hypertension drugs (Aagaard 98). Some e ective non-drug preventive measures and treatments include exercise and reduction of body weight and dietary salt. Other non-drug treatments, such as psychological methods, including relaxation therapy and biofeedback have yielded mixed ndings (Darison et al. 99, McGrady et al. 99, Jacob et al. 99). For example, some studies have suggested that biofeedback and relaxation therapy were more e ective than drug treatment (e.g. hydrochlorothiazide) for reducing stress, anxiety and blood pressure (Sothers & Anker 989, Blanchard 990). Other studies have revealed that relaxation therapy is only e ective for highly motivated patients with favorable family and socioeconomic support (Sothers & Ankers 989, Blanchard 990). Massage therapy has been shown to e ectively reduce anxiety and depression and lower stress hormones including catecholamines (norepinephrine, epinephrine) for di erent age groups and conditions (Field et al. 99, Ironson et al. 996, Field et al. 996). In cardiovascular studies massage therapy has only been used as an adjunct to other forms of therapy. In one study, it was assessed in conjunction with psychotherapy, physical therapy, acupuncture and drug therapy (Demidenko et al. 988), making it di cult to determine whether massage therapy alone would have reduced blood pressure and other symptoms. Moreover, catecholamines and cortisol were not assayed in that study. The present study assessed massage therapy versus progressive muscle relaxation e ects on adults with hypertension. Massage therapy was expected to: () reduce anxiety, depression, and hostility scores; () decrease salivary and urinary cortisol and catecholamine levels (norepinephrine and epinephrine); and (3) lower diastolic blood pressure. Positive e ects were also expected for the progressive muscle relaxation group, although to a lesser degree than for the massage therapy group. Method Table Demographic information and medication type intake by group Participants Thirty adults ( women and 9 men) with at least a 6 month long medical diagnosis of hypertension participated in this study (M age ˆ 5.6 years, S.D. ˆ 8.8 years). Data for ve additional subjects (two from the massage therapy group) were rejected due to non compliance with the treatment protocol. The participants were from middle socioeconomic status (Mˆ.3 on the Hollingshead index), and the ethnicity of the sample was distributed 60% Caucasian, 7% Hispanic and 3% African American. The criterion for inclusion in the study was a medical diagnosis of high blood pressure for at least 6 months duration. Individuals were excluded from participating if they had other medical conditions (e.g. diabetes or psychiatric disorders (e.g. bipolar). Participants reported that their high blood pressure was controlled and that they were highly compliant with their medication intake: and t- tests revealed no di erences between the groups on age, race, and medication type (e.g. beta-blocker vs calcium channel blocker) (Table ). Group Variable Massage Control x t-test P ˆ Age Race Caucasian 0 8 Hispanics 4 4 African Americans 3 Sex Male 6 8 Female 9 7 Medication type Beta blocker 5 6 Calcium channel blocker 6 5 Anticoagulant 3 ACE inhibitor 3

3 Massage therapy Procedures As participants entered the study, they were randomly assigned to a massage therapy (nˆ5) or progressive muscle relaxation (nˆ5) group and were asked to continue their drug and nutritional regimen. Random assignment was determined by the experimenter who drew a number out of a box corresponding to massage () or relaxation (). Participants were informed that the therapies were expected to promote relaxation and reduce stress and therefore talking was discouraged during sessions. Participants who were assigned to the progressive muscle relaxation group were informed that they would receive complementary massage therapy at the end of the study. Massage therapy Participants assigned to this group received 30 min therapy sessions twice a week for ve consecutive weeks during the afternoon or early evening. The massages were conducted by di erent massage therapists assigned on a rotating basis to distribute their abilities across the subject pool and to prevent the potential confound of attachment to a particular therapist. The massage began with the subject in the supine position and progressed in the following sequence: Head/neck (a) Holding the neck with both hands, gentle pressing and stretching to lengthen the spine. (b) With the at of the hand, stroking one side and then the other side of the neck from head to shoulder. (c) Using the ngertips, small circular stroking to the jaw and cheekbone area. (d) Pressing down on the shoulders with the palms of the hand and pressing mid shoulder trigger points. Arms (a) Pulling of the arm down toward the feet and through its natural range of motion, up and over the head and out to the side. (b) Squeezing motions to the hand and using the thumbs, stroking the palm of the hand. (c) Long stroking from the hand up and over the shoulder. (d) Round stroking encircling the shoulder. (e) Squeezing the Hoku points (the eshy part of the webbing that lies between the thumb and the fore nger). Torso (a) Holding the ribs on both sides, gently rocking the ribcage side to side. (b) Placing one hand on the abdomen and the other hand on the forehead and rocking. Legs (a) Holding the ankles, keeping the legs together, pulling straight downward, and then towards the left and then the right side. (b) Squeezing the foot, pressing into the soles of the foot and using friction movements with the thumbs on the top of the foot following the spaces between the bones. (c) Long stroking from the foot to the hip. With the participant in a prone position (a) Lifting leg, bending the foot at the ankle and stretch the back of the calf. (b) Stroking and squeezing up the calf from the ankle to the knee. (c) With the knee bent, rubbing the muscles on the thigh (d) Long stroking from the heel up and over the hips. Back (a) With the heel of the hands on the sides of the spine, pressing into the lower back and stretching the skin towards the sides of the body. (b) Firm stroking from the hip to up and over the shoulders and over the arms (c) Grasping and squeezing the tops of the shoulders. (d) With the edges of both hands on either side of the spine, giving friction to the back from the neck to the hip. (e) Squeezing the back of the neck. (f ) Pressing on the hips with the heel of the hands. (g) From the shoulders down the entire back, long gliding strokes to the feet. (h) With one hand on the lower back and the other on the upper back, slow rocking motions. Progressive muscle relaxation Participants assigned to this group performed 30 min sessions consisting of progressive muscle relaxation exercises twice a week for ve consecutive weeks. Participants were instructed by di erent therapists and researchers on how to perform the sessions and to only perform the sessions on their assigned days (e.g. every Tuesday and Friday afternoon or early evening) to ensure that frequency and session lengths were comparable to the time schedule of the massage therapy group. The relaxation session began with the subject in the supine position. The participant was instructed to breathe deeply for several minutes 33

4 Hernandez-Reif et al. and relax placing the hands alongside the body. Then the participant was asked to follow the verbal instructions consisting of tightening and relaxing di erent muscles of the body in a feet to head progression similar to that progression used in massage therapy. The muscle groups that were exercised were the () feet, () calves, (3) thighs, (4) hands, (5) arms, (6) back and (7) face. Assessments Pre/post treatment assessments (immediate e ects) These assessments were made before and after the sessions on the rst and last days of the 5 week study during our o ce hours. State anxiety inventory (STAI) This is a 0 item inventory on how the subject feels at the moment. Characteristic items include `I feel nervous', `I feel anxious', `I am worried'. The STAI scores increase in response to stress. Research has demonstrated that the STAI has adequate concurrent validity and adequate internal consistency, rˆ0.83, (Spielberger 970, 97). Salivary samples These were collected and assayed for cortisol levels as a measure of stress. The samples were obtained at the beginning of the massage therapy or progressive muscle relaxation session and 0 min after the end of the session on the rst and last days of the study. Due to the 0 min lagtime in cortisol changes, saliva samples always re ect responses to stimulation occurring 0 min prior to sampling (O'Connors & Corrigan 987). Subjects were asked to place a cotton dental swab dipped in sugar-free lemonade crystals along their gumline for 30 s. The swab was then placed in a syringe and the plunger was depressed to express the saliva into a microcentrifuge tube. Lower cortisol levels were expected following the massage sessions based on previous massage therapy studies (Sother & Anchor 989, Ironson et al. 996). Physiological measures Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded using a digital blood pressure monitor (Lumiscope Digitronic). To reduce bias, a second observer veri ed the recordings for approximately onethird of the sample. The digital readings were recorded in the clinic room where the massage therapy or progressive muscle relaxation session occurred. To control for variations in blood pressure, three readings were taken with the participant in a seated position 5 min before and then again three readings 5 min after the therapy. Three readings were also taken with the participant in a reclining position one minute before and three other readings one min after therapy to control for uctuating blood pressure readings. The data were reduced by averaging across the three readings for each assessment (sitting or reclining) period pre and post treatment. First day/last day assessments (longer-term e ects) The following measures were collected before the rst and last day's massage therapy or relaxation session. The Center for Epidemiological Studies Depression Scale (CES-D) This is a 0 item scale that rates depressive symptoms (e.g. `I felt lonely over the past week') on a four-point scale (`rarely or none of the time (0)', `some of the time ()', `occasionally ()', and `most or all the time (3)'). The items included in the scale represent the major symptoms of depression as identi ed by clinical judgment, frequency of use in other questionnaires for depression and factor analytic studies. Each item has a possible value of 0±3; thus the total score has a range of 0±60. The CES-D has very high internal consistency (alpha ˆ 0.86) and test±retest reliability. In addition, reliability and validity for this scale have been acceptable across a variety of demographic characteristics including age, education and ethnic groups (Radlo 977, Radlo 99, Radlo 978). The Symptom Checklist-90 Revised (SCL-90-R) This is a self-report symptom inventory. Only those subscales used for assessing psychological symptoms for depression, anxiety and hostility were administered. Subjects responded to how distressed they felt over the past week on items re ecting depression (e.g. `crying easily'), anxiety (e.g. `heart pounding or racing') and hostility (e.g. `shouting or throwing things'). The questions are rated on a 5-point scale of distress ranging from 0 (`not-at-all distressed') to 4 (`extremely distressed'). This inventory has high reliability measures for internal consistency (M coe cient ˆ 0.84), test±retest (M coe cient ˆ 0.84) and acceptable construct validity (Derogatis). The urinary catecholamines and cortisol These were assayed from samples provided on the rst and last days of the 5 week study. The samples were 34

5 Massage therapy frozen and later assayed by highpressure liquid chromatography with the elcetrochemical detection (HPLC-ECD) technique for cortisol and catecholamines (norepinephrine, epinephrine and dopamine). Brie y, catecholamines are extracted from a 5 ml aliquot of urine using a Biorex 70 column. The extract is injected onto a reverse phase C8, 5 u column. Catecholamines are identi ed by their characteristic elution patterns and quanti ed by using the arearatio method with an internal standard, on a preprogrammed computerized data module. Decreased cortisol and catecholamine levels were expected for the massage therapy group by the end of the 5 week sessions based on earlier massage therapy studies (Field 99, 996) Results Repeated measures multivariate analyses of variance (MANOVAs), analyses of variance (ANOVAs) and Bonferroni t-tests were conducted with pre and post therapy sessions and rst and last days of the study as the repeated measures. Immediate e ects pre-post treatment measures The MANOVA on the short-term measures (STAI, Salivary cortisol and blood pressure) produced a group by days by session interaction e ect, F(3,4) ˆ 4.3, P State Trait Anxiety Inventory (STAI) The ANOVA on the STAI revealed a signi cant e ect of days, F (,8)ˆ 4.55, P50.05, and sessions, F(,8) ˆ 56.8, P50.00, suggesting that anxiety levels were lower for both the massage therapy and relaxation group after the rst and the last day's session (see Table ). Saliva A group by days by session interaction e ect, F (,3) ˆ 5.5, P50.05, revealed a reduction in cortisol only for the massage therapy group after the rst and last massage session on the rst and last days of the study (Table ). Blood pressure No signi cant interaction e ects were obtained for systolic blood pressure. The ANOVA on diastolic blood pressure, however, revealed a group by session interaction e ect for sitting, F (,0) ˆ 5.63, P50.05 and a group by session by day interaction e ect for reclining blood pressure, F (,0) ˆ 3.6, P Subsequent t-tests showed for the massage therapy group a decline () in sitting diastolic blood pressure after the rst and last day's massage and () in reclining blood pressure from the rst to the last day pretreatment (Table ). Table Means (and standard deviationsin parantheses) for massage group and relaxation groups for pre/post session and rst last daysmeasures Massage group Relaxation group First day Last day First day Last day Variables Pre Post Pre Post Pre Post Pre Post Short term measures STAI (anxiety) 36. (.0) a (7.5) b 3.3 (.6) a (8.9) b 39.7 (8.5) a 8.7 (9.3) b 34.7 (5.9) a (3.) b Saliva cortisol.6 (0.6) a. (0.5) b.9 (.) a. (0.6) b. (0.6) b. (0.5) b. (.3) b.4 (.5) b Blood pressure Systolic reclining 35 (5) a 34 (7) a 33 (6) a 3 (4) a 33 () a 3 (3) a 33 (4) a 3 (8) a sitting 40 (9) a 36 () a 4 (9) a 33 (9) b 36 (5) a 34 () a 36 (8) a 38 (0) a Diastolic reclining 83 (9) a 8 (9) a 78 (9) b 8 (7) a 8 (8) a 85 (9) a 84 () a 85 () a sitting 89 (8) a 8 (9) b 85 (6) a 8 (7) b 88 (7) a 88 (6) a 86 (4) a 88 () a Long-term measures First day Last day First day Last day Depression (CES-D) 7.8 (.5) a 8.3 (7.0) b 7. (3.5) a.8 (5.8) c SCL-90R Depression 6.4 (0.) a 5.0 (6.8) b 5. (.0) a.0 (5.4) a Anxiety 5. (4.5) a.3 (.) b 5.4 (5.) a 4.0 (.4) a Hostility 3.5 (.9) a. (0.8) b 3.8 (4.7) a 3. (.) a Di erent letter subscript denotes statistically di erent means within groups for pre/post measures (short-term) or rst/last day measures (longterm). A superscript denoted on a pre measure indicates signi cantly di erent means for rst day pre versus last day pre value. P 0.05, P 0.0, 3 P ˆ 0.005, 4 P ˆ

6 Hernandez-Reif et al. Long-term e ects rst^last day measures The MANOVA on the longer-term measures (CES-D, SCL-90-R) revealed a group by days interaction e ect, E (4,0) ˆ 4.5, P CES-D The ANOVA on the depression score yielded a signi cant e ect of days, F (,8) ˆ 8.3, P50.0, suggesting that depression scores were lower for both the massage therapy and relaxation group by the end of the study. However, an analysis of the change score (i.e. Last day's CES-D score minus baseline CES-D) revealed that depression scores were signi cantly lower for participants receiving massage therapy than for those conducting relaxation sessions t() ˆ.8, P50.0 (Table ). SCL-90-R A signi cant group by days interaction e ect, F (3,) ˆ 3.90, P50.05, and subsequent t-tests revealed a reduction in depression, t (4) ˆ 4.6, P50.0, anxiety, t (4) ˆ 3.6, P 5 0.0, and hostility, t (4) ˆ.3, P50.05, only for the massage therapy group (Table ). Urinary catecholamines and cortisol Scatterplots revealed that the data were not normally distributed. Thus, non-parametric methods were applied. Wilcoxon Matched Pairs Signed Ranks Tests revealed a decrease in urinary cortisol (Z ˆ.3, P50.05) for the massage therapy group (Table 3). Discussion For the massage therapy group, sitting diastolic and systolic blood pressure decreased after the rst and last sessions and reclining diastolic blood pressure declined from the rst to the last day of the 5 week Table 3 Means for massage and relaxation groups.wilcoxon Sign RankTest and p-values for urinary cortisol and catecholamine Massage study. Both the massage therapy and relaxation therapy groups reported less anxiety and depression on two psychometric measures (STAI and CES-D). However, stress hormones (both salivary and urinary cortisol) decreased only for the massage therapy group. Moreover, an additional psychometric measure (SCL-90-R) revealed lower depression, anxiety and hostility scores only for the massage therapy group. The improved psychological state might have contributed to the observed decrease in diastolic blood pressure for the massage therapy group or vice-versa, perhaps via the reduced cortisol production. A decrease in stress hormone production might be the mechanism underlying the observed reduction in diastolic blood pressure in that acute response to stress has been correlated with myocardial damage and even cardiac death (McCubbin, Morse 99). The positive ndings for the massage therapy group might also be the result of increased parasympathetic activity. Vagal tone (an index of parasympathetic activity) has been noted to increase following massage therapy (Sca di 996). That the progressive muscle relaxation group did not show reduced stress hormones or improved scores on the additional psychometric measure (SCL-90-R) contradicts their report of reduced anxiety (STAI) and depression (CES-D) following progressive muscle relaxation. Perhaps the SCL- Relaxation Measure First/Last z= p5 First/Last z= p5 Cortisol 5/ /0.35 NS Norepinephrine 37/47.96 NS 34/ NS Epinephrine 7/ NS 8/7. NS Dopamine 94/84.00 NS 37/ NS 90-R assessment is more sensitive in tapping more hostile depression or anxiety. Moreover, that cortisol stress levels and diastolic blood pressure did not decrease suggests that progressive muscle relaxation may not be e ective for reducing hypertension or associated symptoms. The results are consistent with another study showing that relaxation therapy was not superior to the control condition for medicated hypertension patients (Davison 99), perhaps because relaxation therapy requires compliance and exertion. In contrast, because massage therapy requires no exertion and little if any participation, it might be more e ective in ameliorating symptoms associated with hypertension. An alternative hypothesis might be that the improved scores for the massage therapy group were the result of the additional attention they received from the therapist. Except for the rst and last day's session, which was conducted by a therapist, the relaxation group conducted their sessions at home. Future research might examine if relaxation sessions directed by therapists, as opposed to participants, e ectively reduce symptoms associated with high blood pressure. Why urinary catecholamine levels did not decrease is unclear. Although immediate reduction in stress hormones was evident with massage therapy, decreases in catecholamine production for 36

7 Massage therapy individuals with hypertension symptoms might require longer or more frequent treatments. Or perhaps the participants were not highly stressed as initial levels were only slightly above normal. Future research might examine massage therapy e ects for individuals with hypertension who are highly stressed. Perhaps daily or weekly blood pressure readings, longer-term monitoring of stress hormone production and stress symptoms might help our understanding of the potential e ects of massage therapy as a complementary treatment for hypertension. Longer-term followup might also help determine whether the results re ected shortterm e ects or whether the results would have persisted beyond the treatment sessions. If massage therapy can e ectively reduce symptoms associated with hypertension, then it might reduce life-threatening complications, such as the risk of stroke or heart attack. 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