A randomized, double blind, placebo-controlled, prospective clinical study to demonstrate clinical efficacy of a fixed valerian hops extract combination (Ze 91019) in patients suffering from non-organic sleep disorder.
Level 2 - randomized trial
Individual randomized, double-blind, placebo-controlled clinical trial.
PubMed 17486686 · doi:10.1002/ptr.2167
What was done
In a 4-week, randomized, double-blind, placebo-controlled trial, researchers evaluated patients with non-organic insomnia (ICD-10 F51.0–51.2) who had a baseline sleep latency of at least 30 minutes. Participants received placebo, 500 mg valerian extract alone (Ze 911), or a fixed combination extract (Ze 91019) containing 500 mg valerian extract and 120 mg hops extract. Sleep parameters were objectively measured at home using a portable recording system (QUISI), with reduction in sleep latency (SL2) as the primary outcome.
What was found
The abstract reports that the fixed valerian-hops extract combination was significantly superior to placebo in reducing sleep latency, whereas the single valerian extract failed to show superiority over placebo. No numerical values, effect sizes, or p-values are reported in the abstract.
Why it matters
This trial suggests that combining hops extract with valerian improves objective sleep latency in non-organic insomnia, whereas valerian extract alone was not effective compared to placebo.
Limits
The abstract omits the sample size, numerical data, confidence intervals, and p-values. Long-term efficacy beyond 4 weeks, safety outcomes, and subjective sleep quality metrics are not reported.
Cited by
- supports Valerian root reduces anxiety and is more effective for sleep when combined with hops.