Hypertension, Prehypertension
Conditions
Brief summary
This randomized placebo-controlled study evaluates the efficacy of Nigella sativa (Nisatol®) supplementation in women with borderline blood pressure values or a non-dipper blood pressure phenotype. The study aims to assess the effects of supplementation on blood pressure and resting heart rate in women presenting high-normal blood pressure values (≥130/85 mmHg) and/or a nocturnal non-dipper blood pressure pattern. Participants will be randomly assigned to receive either Nigella sativa (Nisatol®) or placebo for 12 weeks. After the treatment phase, a washout period will be followed by a dietary intervention phase combined with alternate treatment according to the study design. Cardiological and nutritional assessments will be performed at predefined time points.
Detailed description
Hypertension represents one of the main risk factors for cardiovascular diseases, which remain the leading cause of mortality worldwide. In women, cardiovascular risk is often underestimated, resulting in lower adherence to preventive screening and frequent presentation at more advanced stages of cardiovascular disease. Many women present borderline blood pressure values or altered circadian blood pressure patterns, such as the non-dipper phenotype. These conditions may be associated with increased cardiovascular risk and may significantly affect quality of life, particularly in women experiencing climacteric symptoms. Nigella sativa (black cumin seed) has attracted increasing interest as a nutraceutical strategy for improving cardiovascular and metabolic health. Preliminary evidence suggests that supplementation with Nigella sativa may have beneficial effects on blood pressure, lipid profile, and heart rate. This randomized controlled trial will evaluate the efficacy of Nigella sativa (Nisatol®) supplementation compared with placebo in women with borderline blood pressure values and/or a non-dipper blood pressure phenotype. Participants will be randomly assigned to either the intervention group receiving Nisatol® or a control group receiving placebo using formulations that are visually indistinguishable. The initial treatment phase will last 12 weeks. After this phase, treatment will be discontinued and participants will undergo a washout period. Following the washout period, participants will begin a dietary intervention based on a standardized Mediterranean diet combined with the alternate treatment according to the study design. Participants will be evaluated at predefined time points (baseline, 4 weeks, 12 weeks, and final evaluation) to monitor blood pressure, resting heart rate, adherence to treatment, and potential adverse events. Additional assessments will include lipid profile, fasting blood glucose, body composition parameters, gut microbiota analysis, urinary metabolite analysis, and quality-of-life evaluation using validated questionnaires. The results of this study are expected to provide additional evidence regarding the potential role of Nigella sativa supplementation as a nutraceutical strategy for improving cardiovascular parameters and metabolic health in women with borderline blood pressure values.
Interventions
DIETARY_SUPPLEMENTNigella sativa (Nisatol®)
Standardized Nigella sativa extract (Nisatol®) administered orally 2 capsules per day (one capsule in the morning and one in the evening) for 12 weeks.
OTHERPlacebo
Placebo capsules identical in appearance to the Nigella sativa (Nisatol®) 2 capsules per day administered for 12 weeks.
Sponsors
Liaquat University of Medical & Health Sciences
University of Rome Tor Vergata
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Masking description
This study is double-blind. Participants, care providers, investigators, and outcome assessors will be unaware of the treatment allocation. Nisatol® capsules and placebo capsules will be identical in appearance, packaging, and labeling to maintain blinding.
Intervention model description
Participants will be randomly assigned to receive either Nigella sativa extract (Nisatol®) or placebo for the duration of the intervention. The study follows a parallel-group design in which participants remain in their assigned group throughout the study period.
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Female participants * High-normal blood pressure values (≥130/85 mmHg) or mild hypertension (140/90 mmHg) with low cardiovascular risk and no current indication for pharmacological therapy * Presence of a non-dipper blood pressure phenotype on 24-hour ambulatory blood pressure monitoring * Absence of antihypertensive pharmacological treatment
Exclusion criteria
* History of cardiovascular disease * Diabetes mellitus * Severe chronic diseases * Use of medications affecting blood pressure or heart rate * Known allergy to Nigella sativa or fennel
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in systolic blood pressure (mmHg) | Baseline to Week 12 | Assessment of the change in systolic blood pressure measured in mmHg between baseline and Week 12 in women with high-normal systolic blood pressure values (≥130 mmHg) and/or a nocturnal non-dipper hypertension phenotype. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in diastolic blood pressure (mmHg) | Baseline to Week 12 | Assessment of the change in diastolic blood pressure measured in mmHg between baseline and Week 12 in women with high-normal diastolic blood pressure values (≥85 mmHg) and/or a nocturnal non-dipper hypertension phenotype. |
| Change in resting heart rate (beats per minute) | Baseline to Week 12 | Assessment of the change in resting heart rate measured in beats per minute (bpm) between baseline and Week 12 in women presenting climacteric symptoms and/or resting heart rate above 80 bpm. |
| Change in total cholesterol (mg/dL) | Baseline to Week 12 | Assessment of the change in total cholesterol concentration measured in mg/dL between baseline and Week 12 |
| Change in LDL cholesterol (mg/dL) | Baseline to Week 12 | Assessment of the change in low-density lipoprotein (LDL) cholesterol concentration measured in mg/dL between baseline and Week 12. |
| Change in HDL cholesterol (mg/dL) | Baseline to Week 12 | Assessment of the change in high-density lipoprotein (HDL) cholesterol concentration measured in mg/dL between baseline and Week 12. |
| Change in triglycerides (mg/dL) | Baseline to Week 12 | Assessment of the change in triglyceride concentration measured in mg/dL between baseline and Week 12. |
| Change in fasting blood glucose (mg/dL) | Baseline to Week 12 | To assess the effect of Nigella sativa supplementation on fasting blood glucose levels. |
| Change in urinary metabolite concentrations | Baseline to Week 12 | To evaluate the effect of Nigella sativa supplementation on urinary metabolites. |
| Change in gut microbiota composition assessed by 16S rRNA sequencing | Baseline to Week 12 | To evaluate the effect of Nigella sativa supplementation on gut microbiota composition. |
| Change in quality of life assessed by validated questionnaire (SF-36) | Baseline to Week 12 | To analyze the impact of the intervention on quality of life using validated questionnaires, with stratification according to menopausal status. |
| Change in body weight (kg) | Baseline to Week 12 | Assessment of the change in body weight measured in kilograms between baseline and Week 12. |
| Change in body fat percentage (%) | Baseline to Week 12 | Assessment of the change in body fat percentage between baseline and Week 12. |
| Change in basal metabolic rate (kcal/day) | Baseline to Week 12 | Assessment of the change in basal metabolic rate measured in kilocalories per day between baseline and Week 12. |
Countries
Italy
Outcome results
None listed