Effects of Wild Blueberry Ingestion on Motor Performance of People With Parkinson's Disease

The purpose of this study involved investigating the effects of daily ingested wild blueberry drink (22.5 g wild blueberry powder added to pineapple juice) for 8 weeks on movement of people diagnosed with Parkinson's disease. Specifically, the investigators questioned:

• Do the movements of people with Parkinson's disease improve after ingesting the blueberry drink once a day for 8 weeks?
• Do the movements of people with Parkinson's disease after ingesting the blueberry drink show benefits compared to people with Parkinson's ingesting a placebo drink? The investigators hypothesized that supplementation with wild blueberry powder will result in favorable improvements in movements in people with Parkinson's disease that exceed placebo supplementation.

Drinks After meeting entry criteria, people were randomized to receive 22.5 g of wild blueberry powder (equivalent to 1 cup of wild blueberries) or control/placebo added to 170 g of pineapple juice with about four ice cubes and consumed as one drink per day. Participants received at least seven individual powder packets sealed in a baggy along with at least eight 6 oz cans of 100% Dole pineapple juice for each week of the intervention (the investigators included extra in anticipation of rescheduling or mishandling). Most people used their own blender for mixing the drink; however, a few used the shaker bottles with stainless steel wire whisk. Participants returned empty packets, as confirmation of ingestion, during lab visits.

Freeze-dried wild blueberry powder included quick frozen and dehydrated wild blueberries to reduce the moisture content to approximately 2-4%. Placebo matched nutritional properties minus the polyphenols. The Wild Blueberry Association of North America provided BB and placebo powder.

Three pre-screening visits allowed us to ensure participants met study criteria and to start pre-intervention assessments. During visit 1/week -3, the investigators obtained consent, surveyed inclusion/exclusion criteria, measured height and weight, assessed cognition (Mini Mental State Exam), obtained a list of concomitant medication, and completed the taste test to ensure participants agreed to consume either the Placebo and BB drinks for 8 weeks. During visit 2/week -2 and after a 12 hour OFF PD medication (24 hour for dosing once daily) and food withdrawal, participants saw a movement disorder neurologist to complete a physical and neural examination including non-dilated fundoscopic evaluation, obtain vitals, obtain medical history and concomitant medication, assess Hoehn and Yahr stage of PD, and assess motor symptom severity via the Unified Parkinson's Disease Rating Scale (UPDRS-III). Predetermined laboratory assessments at this visit included pregnancy test (if applicable), urinalysis, fasting glucose, and insulin, CHEM 15, and a CBC panel. Visit 3/week -1 involved collection of weight, blood pressure, heart rate, temperature, pulse oxygen, updated medication list, a weekly Food Frequency Questionnaire (FFQ) to determine how many berries, grapes, cherries, juices, or wine people consumed in the previous week, UPDRS-III, and functional assessments to expose participants to objective and clinical measures of standing balance, gait, and physical function used for pre and post intervention while on their normal medication schedule. The investigators explained and provided instructions on how to complete nutritional assessments involving a 3-day food record which included details about all food consumption for 3 non-consecutive days (time, location, what, and how much consumed) and a Diet History Questionnaire II requesting what, how often, and how much they ate of different foods over the last year. Researchers instructed participants how to wear a waist-mounted activity monitor for seven days and provided verbal and written instructions to record the start time and type of each activity in an activity diary. The investigators called participants three times during the next seven days to help ensure adherence. The investigators also encouraged participants to call investigators with questions/concerns.

Week 0 involved pre-testing not completed at the physician visit with similar procedures and content to week -1. Assessments included weight, blood pressure, heart rate, temperature, pulse oxygen, updated medication list, a weekly FFQ, UPDRS-III, and functional assessments. The investigators reviewed the nutritional assessments and activity diary for accuracy, updating incomplete items, and retrieved the activity monitor. Each newly randomized participant received powder packets (BB or Placebo), pineapple juice, instructions on how to mix their drink, and adverse events diary, in which people reported the time of drink consumption and whether any adverse events occurred that day. Again, the investigators called participants three times each week through study completion to help ensure they consumed the drink and completed adverse events log and encouraged them to call investigators with questions/concerns.

During weeks 1-6, the investigators recorded weight, blood pressure, heart rate, temperature, pulse oxygen, a weekly FFQ, and reviewed the presence of adverse events, if any. Participants brought back empty packets as evidence of ingestion. Collections occurred weekly for most participants, allowing them to pick up more powder and juice for the next week. For those living farther away or with conflicts, the investigators collected as much data as possible over the phone and ensured the investigators sent home enough powder and juice until their next visit.

One week before the final visit in addition recording weight, blood pressure, heart rate, temperature, pulse oxygen, a weekly FFQ, and reviewing the presence of adverse events, the investigators reviewed and provided instructions on how to complete the 3-day food record and activity diary and how to wear the activity monitor. This occurred around week 7-8.

For the last visits (week 8 ± 1 week), the investigators repeated the visit to the neurologist after the food and PD medication (OFF) withdrawal (visit 2) and without the possible pregnancy test. During a separate visit because of the ON medication requirement, the investigators collected weight, blood pressure, heart rate, temperature, pulse oxygen, updated medication list, a weekly FFQ, UPDRS-III, and functional assessments for post-testing. The investigators reviewed the 3-day food record and activity diary for accuracy and updated incomplete items. The investigators also received the activity monitor and downloaded the data.