Two hundred ten participants (140 men, mean age (SD) of 67.9 (9.6), range 44–89 years) were randomized. Participants generally had mild to moderately severe PD, reflected by a median modified HY stage (IQR) of 2.5 (2-3) and mean (SD) disease duration of 6.7 (5.6) years. Activity limitations, as measured by the Unified Parkinson's Disease Rating Scale (UPDRS) Part II activities of daily living, were also mild (mean (SD); 11.6 (5.9)). One hundred sixteen participants (55%) reported having falls over the previous 12 months, of whom 74 (64%) were repeat fallers. Freezing of gait was reported by more than half of the participants. Arthritis was the most commonly reported health condition, present in 92 (44%) of the sample, and 48 (23%) participants had a history of cancer or heart disease. The majority of participants were taking levodopa preparations or a combination of PD medications, with 19 on no PD-pharmacotherapy. One hundred fourteen (54%) participants were prescribed four or more medications, with 89 (42%) taking psychotropic medication.
3.2. Delivery of Interventions
The interventions were undertaken in four different outpatient centers located in different regions of Melbourne. Across the three years of the RCT, 8 physical therapists delivered the MST, 10 physical therapists delivered the PST and 6 occupational therapists or social workers delivered the LS program. Therapist professional experience varied markedly from new graduate (<1 year) to highly experienced (>30 years).
The safety of the interventions was assessed in three ways and is reported in . Structured weekly screening during the intervention phase identified new soreness lasting longer than 48 hours in 28 individuals (PST n = 18; MST n = 10). Seven individuals reported more than one episode of soreness (PST n = 6; MST n = 1). Typical reports included a transient increase of preexisting low back, hip or knee pain related to osteoarthritis, resolved by a modified program or over-the-counter medication. Fewer than one quarter of these participants attended a health service practitioner because of new soreness. No new soreness was reported to persist beyond the intervention phase and require intervention.
Safety during the intervention phase.
Secondly, three incidents occurred during the actual intervention sessions. Two MST participants reported single episodes of dizziness with subsequent medical assessment that were resolved without intervention or sequelae. A single participant from the PST group fell during the therapy session, with no reported injury. None of these incidents resulted in any ongoing consequence.
The third safety evaluation examined falls in 203 participants during the intervention phase. Fifty-eight people fell during this phase: (PST n = 10, MST n = 24, LS n = 24). Falls frequency varied markedly; 32 people fell once or twice; 19 fell between 3 to 9 times; 7 fell 10 or more times. The median time to the first fall during the intervention phase was 14 days in the PST group and 9 days in the MST and LS groups. The time to first fall did not differ significantly between groups; Log rank test (Mantel Cox), Chi square = 2.08, df = 2, P = 0.353.
Three aspects of retention of participants were considered related to attendance at the three posttherapy assessments and the return of Falls Calendars. The study protocol had allowed for a drop-out rate of 15% when determining the required sample size. Seven participants, six in the LS group and one in the MST group, withdrew prior to the intervention phase after being randomized to a group. Reasons for withdrawal included poor health (LS n = 2), a preference for the exercise group (LS n = 1), unable or no longer wanting to attend (LS n = 2, MST n = 1), and deceased (LS n = 1). Eight participants withdrew from the study during or after the intervention phase and did not return Falls Calendars during the 12 months follow-up phase. Six of these withdrew from the LS program, two due to health reasons, one as they did not want to continue (unspecified reason), one because he felt the group was “depressing”, and two as they were not exercising or receiving falls education. One participant withdrew from PST for health reasons, and one participant from the MST group died of unrelated causes. One hundred ninety-six (93%) of the participants completed the T2 assessment at the end of the 8-week intervention phase (PST n = 69; MST n = 68; LS/control n = 59; see ).
Assessments attended across the course of the trial.
Retention throughout the full trial period was high. One hundred ninety-five participants (93%) returned one or more Falls Calendars during the 12-month follow-up period (PST n = 69, MST n = 67, LS n = 59). One hundred eighty-four participants (88%) provided falls data for the entire 12 months (PST n = 65, MST n = 65, LS n = 54). In the final evaluation of retention, 775 assessments of possible 840 (210 × 4 occasions) were completed (92%). Participation at the final T4 assessment as a percentage of the total number randomized showed 93% of people in the PST group were reassessed, 91% of MST and 79% of participants in the LS program.
Eight participants were randomized, but did not attend any therapy sessions (PST n = 0, MST n = 2, LS n = 6). Adherence data are reported for the participants who attended at least one intervention session (PST n = 70, MST n = 67, LS n = 65). Ninety percent of the PST participants attended between 6 and 8 sessions, with 3 participants (4%) attending fewer than 5 sessions. Ninety-three percent of the MST participants attended 6–8 sessions, with 2 participants (3%) attending fewer than 5 sessions. Seventy-eight percent of the LS participants attended between 6 and 8 sessions, with six participants (9%) attending fewer than 5 sessions. Participant attendance (as defined by attendance at ≥6 sessions or 75%) did not differ across the three groups (independent samples Kruskal-Wallis, P = .435). The PST group attended 82.5% of available sessions, the MST group 90.5%, and the LS group 80.7%.
3.6.1. Progressive Strength Training Group
A review of the therapy records indicated that 89% of the participants were able to complete all seven suggested exercises within the 2-hour session. The remaining 11% were able to complete six exercises. Increasing the number of repetitions and/or sets was the most common form of progression, with 97% of participants (68 of 70) progressing in this manner. Eighty percent (56 of 70) of the participants used the vest with weights during the appropriate exercises. Of these, only 5 participants (9%) did not increase the weights across the course of the intervention. Both the step platform and Thera-band (to resist trunk extension/rotation) were used by all participants. Thera-band resistance was increased for 57% of participants.
3.6.2. Movement Strategy Training Group
A review of the available therapy records (n = 64, missing data = 3) indicated that over 86% (55/64) of the participants were able to routinely complete six or all seven activities within the 2-hour period. Increasing the number of repetitions and sets was the most common form of program progression, in conjunction with increasing the difficulty of the task. Progression of the task was highly variable according to each individual's task performance. For example, standing and reaching to an object in front of the participant may have progressed to moving the object further away, standing and placing an object down on the ground or up on a high shelf, to moving a heavier or more cumbersome object. Similarly, walking a straight line with long steps might have progressed to walking with a secondary motor task, with a secondary cognitive activity, to an obstacle course; standing up from a chair may have progressed by altering the height or compliance of the chair, or to standing up with an object in hand or standing up and walking off.