Sistematični pregled in metaanaliza vpliva vitamina C na krvni tlak

Horvat, Tjaša (avtor), Mravljak, Janez (mentor)

Hipertenzija oziroma visok krvni tlak spada med srčno-žilne bolezni, ki so eden glavnih vzrokov umrljivosti po svetu. Na njen razvoj vpliva več dejavnikov; med drugim tudi oksidativni stres, saj povzroča motnje v celični signalizaciji ter strukturne in funkcionalne spremembe v ožilju, ledvicah in živčnem sistemu. Poleg tega spodbuja sistemsko vnetje in aktivacijo imunskih celic, kar vse skupaj vpliva na zvišanje krvnega tlaka. Zaradi naraščajočega števila raziskav, ki kažejo, da bi lahko bil oksidativni stres eden od dejavnikov pri razvoju hipertenzije, se je pojavila možnost, da bi lahko na uravnavanje krvnega tlaka vplivali tudi antioksidanti, med katere spada vitamin C. Da ugotovimo, ali vitamin C vpliva na znižanje krvnega tlaka, smo izvedli sistematičen pregled literature, v katerega smo vključili 435 raziskav iz podatkovnih baz PubMed, Google Scholar in Web of Science. Za sistematični pregled je bilo ustreznih 19 raziskav, ki so obravnavale vpliv vitamina C na sistolični in diastolični krvni tlak. Vse raziskave smo najprej ocenili po kakovosti, izpisali osnovne podatke ter jih povzeli v preglednici. Izmed vključenih raziskav v sistematični pregled jih je 12 imelo ustrezne podatke za izvedbo metaanalize. Statistično smo ovrednotili vpliva vitamina C na sistoličen in diastoličen krvni tlak tako pri mešani populaciji kot tudi pri hipertenzivnih in normotenzivnih osebah. Skupno smo izvedli šest metaanaliz, vendar v nobeni nismo zaznali statistično značilne razlike med eksperimentalno in kontrolno skupino. Najbolj obetavni rezultati so se pokazali pri metaanalizi vpliva vitamina C na sistolični krvni tlak pri hipertenzivnih posameznikih, kjer so bile vrednosti p zelo nizke, kar nakazuje na potencialni učinek, vendar je bilo število vključenih raziskav zelo majhno. Med petimi raziskavami, ki jih nismo vključili v metaanalizo, smo izvedli vsebinsko primerjavo. Te raziskave so bile skladne v ugotovitvi, da ima vitamin C vpliv na znižanje sistoličnega krvnega tlaka – vse so pokazale statistično značilno razliko med eksperimentalno in kontrolno skupino, vpliv na diastolični krvni tlak pa je bil potrjen le v treh raziskavah. Čeprav rezultati sistematičnega pregleda in metaanalize nakazujejo potencialni vpliv vitamina C na krvni tlak, so ugotovitve premalo zanesljive in med seboj neenotne, zato je na tem področju potrebno večje število raziskav s standardiziranimi metodami, ki bodo zagotovile večjo primerljivost rezultatov.

• Jezik: Slovenski jezik
• Ključne besede: Vitamin C, hipertenzija, sistematičen pregled literature, metaanaliza
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: FFA - Fakulteta za farmacijo
• Leto izida: 2025
• PID: 20.500.12556/RUL-175955
• COBISS.SI-ID: 258099203
• Datum objave v RUL: 14.11.2025

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Systematic review and meta-analysis of vitamin C effect on blood pressure

Izvleček

Hypertension, or high blood pressure, is classified among cardiovascular diseases, which are one of the leading causes of mortality worldwide. Its development is influenced by several factors, among them oxidative stress, which disrupts cellular signalling and causes structural and functional changes in blood vessels, kidneys, and the nervous system. In addition, it promotes systemic inflammation and activation of immune cells, all of which contribute to elevated blood pressure. Due to the increasing number of studies suggesting that oxidative stress may be one of the factors in the development of hypertension, the possibility has emerged that blood pressure regulation could also be influenced by antioxidants, including vitamin C. To determine whether vitamin C affects the reduction of blood pressure, we conducted a systematic literature review that included 435 studies from the PubMed, Google Scholar, and Web of Science databases. Nineteen studies were eligible for systematic review, as they examined the effect of vitamin C on systolic and diastolic blood pressure. All studies were first evaluated for quality, and basic data were extracted and summarized in a table. Of the studies included in the systematic review, 12 provided sufficient data for a meta-analysis. We statistically evaluated the effect of vitamin C on systolic and diastolic blood pressure both in the general population and separately in hypertensive and normotensive individuals. In total, six meta-analyses were performed; however, none demonstrated a statistically significant difference between the experimental and control groups. The most promising results were observed in the meta-analysis assessing the effect of vitamin C on systolic blood pressure in hypertensive individuals, where p-values were very low, suggesting a potential effect, although the number of included studies was very small. For the five studies not included in the meta-analysis, a qualitative comparison was performed. These studies consistently indicated that vitamin C lowers systolic blood pressure — all reported a statistically significant difference between the experimental and control groups — while an effect on diastolic blood pressure was confirmed in only three studies. Although the results of the systematic review and meta-analysis suggest a potential effect of vitamin C on blood pressure, the findings are insufficiently reliable and inconsistent. Therefore, a larger number of studies using standardized methodologies will be required in this field to ensure greater comparability of results.

• Ključne besede: Vitamin C, hypertension, systematic literature review, meta-analysis