Nattokinase for cardiovascular risk, gut bacteria, sleep, and thinking in people with metabolic syndrome and sleep apnea

Effects of Nattokinase on Cardiovascular Disease Risk Factors, Gut Microbiota, Sleeping and Cognitive Function in Patients With Risk of Metabolic Syndrome Along With Sleeping Disorder.

This trial will test whether taking nattokinase daily helps lower heart disease risk markers, change gut bacteria, improve sleep, and support thinking in adults with metabolic syndrome risk and mild-to-moderate sleep apnea.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 80 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Taipei Medical University (other)
• Locations: 1 site (Taipei)
• Trial ID: NCT07229521 on ClinicalTrials.gov

What this trial studies

This is a randomized, double-blind, placebo-controlled crossover trial enrolling 70–80 adults at risk for metabolic syndrome who have mild-to-moderate sleep apnea (AHI 5–30). Participants will take either nattokinase (two capsules daily, 3000 FU per capsule) or matching placebo for 12 weeks, undergo a 2-week washout, then cross over to the other arm for a second 12-week period. Investigators will collect clinical and laboratory measures of cardiovascular risk, stool samples to analyze gut microbiota, sleep measures (PSG or HSAT and sleep questionnaires), and brief cognitive tests before and after each treatment period. The crossover, within-subject design aims to reduce variability and compare each participant’s response to nattokinase versus placebo.

Who should consider this trial

Good fit: Adults over 18 with at least two metabolic-syndrome risk criteria and mild-to-moderate sleep apnea (AHI 5–30) who do not have major psychiatric illness or other primary sleep disorders are ideal candidates.

Not a fit: People with BMI over 30, severe sleep apnea (AHI >30), significant chronic liver disease, other primary sleep disorders, or major mental illness are unlikely to qualify or receive benefit from this protocol.

Why it matters

Potential benefit: If successful, nattokinase could meaningfully reduce clotting-related cardiovascular risk markers, improve sleep quality, favorably alter gut microbiota, and help preserve age-related cognitive function in this patient group.

How similar studies have performed: Nattokinase has documented fibrinolytic (thrombolytic) effects in prior research, but its effects on gut microbiota, sleep quality, and cognition in humans remain largely untested.

Eligibility criteria

Inclusion Criteria:

1. Over 18 years old
2. Meet the criteria of MetS: meet at least two of the following four items will be recognized as at risk of metabolic syndrome:

   1. Abdominal obesity: Male≧90cm (35 inches); Female≧80cm (31inches)
   2. High blood pressure: Systolic blood pressure≧120mmHg or diastolic blood pressure≧80mmHg
   3. High fasting blood glucose: Fasting blood glucose≧100mg/dL
   4. Dyslipidemia: High fasting triglycerides (≧150mg/dL) or low high-density lipoprotein cholesterol (HDL-C) (\<40mg/dL for male, \<50mg/dL for female)
3. The Apnea Hypopnea Index (AHI) was diagnosed by overnight multi-channel sleep physiology examination (Polysomnography, PSG) or Home Sleep Apnea Test (HSAT) to be between 5 and 30, indicating mild or moderate sleep apnea.
4. No major mental illness or obvious symptoms of anxiety or depression
5. No combination with other primary sleep diseases

Exclusion Criteria:

1. Body mass index (BMI) \>30 kg/m\^2
2. Chronic diseases: abnormal liver and kidney function, abnormal gastrointestinal function, cardiovascular disease, high blood pressure, diabetes mellitus, and hyperlipidemia, etc.
3. Participants requiring medication for conditions not specified in exclusion criterion (2), who are unable to maintain a stable treatment regimen throughout the trial
4. Malignant tumors
5. Pregnancy or breastfeeding
6. Person expected to perform the surgery.
7. Those who have participated in other clinical trials in the past 28 days.
8. May be allergic to the ingredients in the test materials, or take drugs or dietary supplements that may affect the test results

Where this trial is running

Taipei

• Taipei Medical University — Taipei, Taiwan (RECRUITING)

Study contacts

• Study coordinator: Suh-Ching Yang

Conditions: Metabolic Syndrome, Sleeping Disorders