Jace Schell, R. Hal Scofield, James R. Barrett, Biji T. Kurien, Nancy Betts, Timothy J. Lyons, Yan Daniel Zhao, and Arpita Basu
Nutrients 2017, 9, 949; doi:10.3390/nu9090949.
JACO Editorial Reviewer: Scott D. Banks, DC, MS
Published: December 2017
Journal of the Academy of Chiropractic Orthopedists
December 2017, Volume 14, Issue 4
The original article copyright belongs to the original publisher. This review is available from: http://www.dcorthoacademy.com
© 2017 Banks and the Academy of Chiropractic Orthopedists. This is an Open Access article which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Osteoarthritis (OA), the most common form of arthritis, is a significant public health burden in U.S. adults. Among its many risk factors, obesity is a key player, causing inflammation, pain, impaired joint function, and reduced quality of life. Dietary polyphenols and other bioactive compounds in berries, curcumin, and tea have shown effects in ameliorating pain and inflammation in OA, but few clinical studies have been reported. The purpose of the present study was to examine the effects of dietary strawberries on pain, markers of inflammation, and quality of life indicators in obese adults with OA of the knee. In a randomized, double-blind cross-over trial, adults with radiographic evidence of knee OA (n = 17; body mass index (BMI): (mean SD) 39.1 + 1.5; age (years): 57 + 7) were randomized to a reconstituted freeze-dried strawberry beverage (50 g/day) or control beverage daily, each for 12 weeks, separated by a 2-week washout phase (total duration, 26 weeks). Blood draws and assessments of pain and quality of life indicators were conducted using the Visual Analog Scale for Pain (VAS Pain), Measures of Intermittent and Constant Osteoarthritis Pain (ICOAP), and Health Assessment Questionnaire-Disability Index (HAQ-DI) questionnaires, which were completed at baseline and at weeks 12, 14, and 26 of the study. Among the serum biomarkers of inflammation and cartilage degradation, interleukin (IL)-6, IL-1, and matrix metalloproteinase (MMP)-3 were significantly decreased after strawberry vs. control treatment (all p < 0.05). Strawberry supplementation also significantly reduced constant, intermittent, and total pain as evaluated by the ICOAP questionnaire as well as the HAQ-DI scores (all p < 0.05). No effects of treatment were noted on serum C-reactive protein (CRP), nitrite, glucose, and lipid profiles. Dietary strawberries may have significant analgesic and anti-inflammatory effects in obese adults with established knee OA.
JACO Editorial Summary:
- The morbidity rates with drug treatments for chronic osteoarthritic pain have driven interest in natural therapies noted for the far superior safety profile. Some of the more studied include plant phenols such as derived from turmeric, ginger and other food items.
- Clinical benefit has been previously been demonstrated in metabolic syndrome with phenolics from berries such as strawberries. As metabolic syndrome and osteoarthritis share a major driving mechanism, inflammation, it was sought to measure their impact on both inflammatory and clinical features in osteoarthritic patients.
- Inflammatory biomarkers (IL-6, IL1b), tissue degeneration markers (matrix metalloproteinase (MMP)-3) and clinical outcome markers (ICOAP questionnaire and HAQ-DI scores) significantly improved after 12 weeks of active supplementation confirming the original hypothesis.
- No adverse effects were seen although the study population was only 17 subjects. Some adverse effects would be anticipated over the 12 weeks of observation in this study with NSAIDs.
- The applicability of the data to broader populations is difficult as the study population was significantly obese. As obesity is highly associated with a background pro-inflammatory state could be argued that the clinical effect may be greater in a non-obese population.
- Although similar outcomes have been shown with many phenolic food sources, very little is known about their comparative efficacy to guide current clinical application beyond clinician experience. Some study has found synergistic combinations of phenolic food sources to produce better outcomes that monotherapies and this should also be considered.
The study supports the idea of the use of plant phenolics such as strawberries are a beneficial option perhaps better suited to long-term use as is needed in osteoarthritis. They may be particularly helpful in the management of patients who have already had adverse effects with drug therapies.