Quality of life and safety of a dietary intervention with French maritime pine bark extract (Pycnogenol®) in women with osteoporotic bone loss: a randomized, placebo-controlled double-blind study-Part II

INTRODUCTION: In the pre-therapeutic stage of osteopenia or clinically stable osteoporosis dietary supplements are frequently used, but often evidence for benefits and risks is sparse. The French maritime pine bark extract Pycnogenol® has anti-inflammatory and antioxidative effects. Although beneficial impact on various health conditions has been recorded, no data regarding the impact on quality of life and safety of Pycnogenol® supplementation in osteopenia and stable osteoporosis is available yet. METHODS: In a randomized, double-blind, placebo-controlled clinical trial, 67 women received Pycnogenol® (100 mg twice daily; n = 33) or placebo (n = 34) for 3 months, after which all participants took Pycnogenol® for additional 3 months in an active-treatment extension phase. The quality of life was assessed by two validated questionnaires and biochemical safety indicators, including blood count, liver and kidney function, markers of inflammation and mineral metabolism were analyzed. RESULTS: During the randomized placebo-controlled phase, the SF-36v2 bodily pain score improved in the Pycnogenol® group while remaining unchanged under placebo. This effect persisted after adjustment for baseline values (p = 0.0106). A comparable difference was observed for vitality (p = 0.0282). The total QUALEFFO-41 score did not differ between the groups. In the QUALEFFO-41 pain domain, scores were lower after 6 months in the group treated continuously with Pycnogenol® than in the group switched from placebo (p = 0.0231). During the intake of Pycnogenol®, the activities of the liver enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT) remained stable, while a minor decrease in gamma glutamyl transferase (GGT) was significant (p = 0.0141) in the switched-over group. No significant changes were observed regarding blood count, kidney function (glomerular filtration rate GFR; blood urea) and inflammation (C-reactive protein; CRP). Serum phosphate concentrations declined under Pycnogenol® within the reference range, reaching statistical significance after 6 months during the extension phase (p = 0.0039). CONCLUSION: Dietary supplementation with Pycnogenol® maintained physiological blood count, markers of liver and kidney function, thus supporting the favorable safety of the plant extract. Additionally, participants receiving Pycnogenol® experienced significant improvements in pain-related and vitality-related quality of life during the randomized placebo-controlled phase. CLINICAL TRIAL REGISTRATION: https://drks.de/search/de/trial/DRKS00026630, identifier DRKS00026630.