RCT: Vitamin K2 Reduces Nocturnal Leg Cramps in Older Adults
28 Oct, 2024 | 18:59h | UTCBackground Nocturnal leg cramps (NLCs) affect 50% to 60% of adults, causing significant discomfort, sleep disturbances, and reduced quality of life. Current treatments lack robust evidence for efficacy and safety, with quinine no longer recommended due to severe adverse effects. Vitamin K2 has shown promise in reducing muscle cramps in dialysis patients, suggesting potential benefits for managing NLCs.
Objective To evaluate whether vitamin K2 supplementation reduces the frequency, duration, and severity of nocturnal leg cramps in older adults compared with placebo.
Methods In this multicenter, double-blind, placebo-controlled randomized clinical trial conducted in China from September 2022 to December 2023, 199 community-dwelling individuals aged 65 years or older with at least two episodes of NLCs over a two-week screening period were enrolled. Participants were randomly assigned in a 1:1 ratio to receive daily oral vitamin K2 (menaquinone-7, 180 μg) or placebo for eight weeks. The primary outcome was the mean number of NLCs per week. Secondary outcomes included cramp duration and severity, measured on a 1 to 10 analog scale.
Results Of the 199 participants (mean age 72.3 ± 5.5 years; 54.3% female), 103 received vitamin K2 and 96 received placebo. Baseline weekly cramp frequency was similar between groups (vitamin K2: 2.60 ± 0.81; placebo: 2.71 ± 0.80). Over eight weeks, the vitamin K2 group experienced a significant reduction in mean weekly cramps to 0.96 ± 1.41, while the placebo group increased to 3.63 ± 2.20 (between-group difference: −2.67; 95% CI, −2.86 to −2.49; P < .001). The vitamin K2 group also showed greater reductions in cramp severity (mean decrease of 2.55 ± 2.12 points vs 1.24 ± 1.16 points in placebo) and duration (mean decrease of 0.90 ± 0.88 minutes vs 0.32 ± 0.78 minutes in placebo). No adverse events related to vitamin K2 were reported.
Conclusions Vitamin K2 supplementation significantly reduced the frequency, severity, and duration of nocturnal leg cramps in older adults, demonstrating both efficacy and safety.
Implications for Practice Vitamin K2 may offer an effective and safe therapeutic option for managing NLCs in older individuals, addressing a significant unmet clinical need in primary care.
Study Strengths and Limitations Strengths include the randomized, double-blind design and focus on an older population; limitations involve the relatively mild symptoms of participants and lack of assessment of quality of life or sleep improvements.
Future Research Further studies should assess the impact of vitamin K2 on sleep quality and quality of life in patients with more severe NLCs and explore the underlying mechanisms of its muscle-relaxing effects.