Blueberries Improve Pain, Gait Performance, and Inflammation in Individuals with Symptomatic Knee Osteoarthritis.

Nutrients. 2019;11(2)
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Osteoarthritis (OA) is the most common joint disorder in the world. Inflammation is one of the major drivers of the progression of OA, which typically involves progressive loss of the structure and function of joint cartilage. Polyphenols, which are compounds found in plant foods such as spices, tea, dark chocolate and dark-coloured berries, have been studied for their anti-inflammatory properties. Blueberries are high in dietary polyphenols, so researchers proposed that the regular consumption of blueberries may help improve OA. The purpose of this randomised, double-blind trial was to examine the effect of freeze-dried whole blueberries on pain, inflammation and walking ability in people with knee OA. A group of adults aged 45 to 79 with knee OA, consumed either 40g freeze-dried blueberry powder or maltodextrin powder (placebo) daily for four months. Blood draws and assessment of pain and walking were conducted at baseline, two months, and four months. Pain, stiffness, and difficulty to perform daily activities improved significantly in the blueberry treatment group, with no change in the placebo group. Some measures of walking ability improved in the blueberry group. No statistically significant changes were observed in blood levels of inflammatory markers in either of the groups. However, an increasing trend for interleukin (IL)-13 concentration and a decreasing trend in monocyte chemoattractant protein-1 (MCP-1) concentration were seen in the blueberry group. The findings of this study suggest that daily incorporation of whole blueberries may reduce pain, stiffness, and difficulty to perform daily activities, while improving walking ability, and would therefore improve quality of life in individuals with knee OA.

Abstract

Osteoarthritis (OA) is the most common joint disorder in the world and is the most frequent cause of walking related disability among older adults in the US, which brings a significant economic burden and reduces quality of life. The initiation and development of OA typically involves degeneration or progressive loss of the structure and function of articular cartilage. Inflammation is one of the major drives of the progression of OA. Dietary polyphenols have been studied for their anti-inflammatory properties and potential anabolic effects on the cartilage cells. Blueberries are widely consumed and are high in dietary polyphenols, therefore regular consumption of blueberries may help improve OA. The purpose of the present study was to examine the effect of freeze dried whole blueberries on pain, gait performance, and inflammation in individuals with symptomatic knee OA. In a randomized, double-blind trial, adults age 45 to 79 with symptomatic knee OA, were randomized to either consume 40 g freeze-dried blueberry powder (n = 33) or placebo powder (n = 30) daily for four months. Blood draws and assessment of pain and gait were conducted at baseline, two months, and four months. Western Ontario McMaster Osteoarthritis Index (WOMAC) questionnaires were used to assess pain and GAITRite® electronic walkway was used to evaluate gait spatiotemporal parameters. WOMAC total score and sub-groups, including pain, stiffness, and difficulty to perform daily activities decreased significantly in the blueberry treatment group (p < 0.05), but improvement of WOMAC total score and difficulty to perform daily activities were not observed in the placebo group. Normal walking pace single support percentage for both limbs increased (p = or < 0.007), while double support percentage for both limbs decreased in the blueberry treatment group (p = or < 0.003). No significant changes were observed in plasma concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-10, IL-13, matrix metalloproteinases (MMP)-3, MMP-13, and monocyte chemoattractant protein-1 (MCP-1) in both treatment groups. However, an increasing trend for IL-13 concentration and a decreasing trend in MCP-1 concentration were noted in the blueberry group. The findings of this study suggest that daily incorporation of whole blueberries may reduce pain, stiffness, and difficulty to perform daily activities, while improving gait performance, and would therefore improve quality of life in individuals with symptomatic knee OA.

Lifestyle medicine

Fundamental Clinical Imbalances : Immune and inflammation
Patient Centred Factors : Mediators/Inflammation
Environmental Inputs : Nutrients
Personal Lifestyle Factors : Nutrition
Functional Laboratory Testing : Blood

Methodological quality

Jadad score : 3
Allocation concealment : No

Metadata

Nutrition Evidence keywords : Osteoarthritis ; Joint health ; Phytochemicals ; Phytonutrients ; Berries