Practice-based randomized controlled-comparison clinical trial of chiropractic adjustments and brief massage treatment at sites of subluxation in subjects with essential hypertension: a pilot study.

Plaugher G, Long CR, Alcantara J, Silveus AD, Wood H, Lotun K, Menke JM, Meeker WC, Rowe SH. Practice-based randomized controlled-comparison clinical trial of chiropractic adjustments and brief massage treatment at sites of subluxation in subjects with essential hypertension: a pilot study. J Manipulative Physiol Ther. 2002;25:221-239

Abstract:

Objective: The primary purpose of this pilot study is to determine the feasibility of conducting a randomized clinical trial in the private practice setting that will examine short and long-term effects of chiropractic adjustments in the care of subjects with essential hypertension compared to a brief soft tissue massage, and an non-treatment control group.

Design: Randomized controlled-comparison trial using three parallel groups. After an initial one-week (three visits) baseline subjects were randomized into either chiropractic adjustments, brief massage or non-treatment control groups. Treatment/control visits were over a two-month period with follow-up visits at two-weeks, one month and two months. Evaluations were obtained in a blinded fashion with a random-zero sphygmomanometer. Examiner reliability of the BP evaluations was determined prior to the initiation of the trial. The intra-examiner ICC coefficients were >.92.

Setting: Private practice outpatient chiropractic clinic.

Patients: Twenty-three subjects between the ages of 24 and 50 years, with systolic and/or diastrlic essential hypertension.

Interventions: Two-months of full spine chiropractic care (i.e., Gonstead) consisting primarily of specific-contact, short lever arm adjustments delivered at motion segments exhibiting signs of subluxation. The massage group had a brief effleurage procedure delivered at localized regions of the spine thought to be exhibiting signs of subluxation. The nontreatment control group rested along for a period of approximately five-minutes in an adjustment room.

Main Outcome Measures: Cost per enrolled subject, as well as systolic and diastolic blood pressure measured with a random-zero sphygmomanometer and patient reported health status (SF-36). Blood pressure evaluations were obtained at each clinic visit and at follow-up evaluations. Pilot study outcome measures also included an assessment of cooperation of subjects to randomization procedures and drop-out rates, recruitment effectiveness, analysis of temporal stability of blood pressures at the beginning of care, and the effects of inclusion/exclusion criteria on the subject pool.

Results: There were 86 subjects screened and 30 were eligible and enrolled, yielding a cost of $161.00 per enrolled subject. One subject was later determined ineligible and six others dropped out. The average age of the remaining 23 subjects was 39 years and 65% were female; in the chiropractic and massage therapy groups, all subjects were classified as either overweight or obese; in the control group there were only two classified as such. SF-36 profiles for the groups were similar to that of a normal population. The mean change in diastolic blood pressure was –4 (95% confidence interval (CI): - 8.6, 0.5) in the chiropractic care group, 0.5 (95% CI: -3.5, 4.5) in the brief massage treatment group, and –4.9 (95% CI: - 9.7, -0.1) in the no treatment control group. At the end of the study period, this change was –6.3 (95% CI: 13.1, 0.4), -1.0 (95% CI: -7.5, 15.6), -7.2 (95% CI: -13.3, -1.1) in the three study groups. The mean improvements in the chiropractic care and no treatment control groups remained consistent over the follow-up period.

Conclusions: This pilot study elucidated several procedural issues that should be addressed before undertaking a full scale clinical trial on the effects of chiropractic adjustments in patients with essential hypertension. A multidisciplinary approach to recruitment may need to be used in any future efforts due to the limited subject pool of patients who have hypertensive disease but are not taking medications for its control. A one-week run-in period may be necessary prior to randomization, in order to exclude subjects who may only be exhibiting white coat hypertension. In addition, measures need to be used to assure comparable groups regarding prognostic variables such as weight. Studies such as these demonstrate the feasibility of conducting a full-scale three-group randomized clinical trial in the private practice setting.