Cimet za šećernu bolest
Abstract
Background
Diabetes mellitus is a chronic metabolic disorder that is associated with an increased risk of cardiovascular disease, retinopathy, nephropathy, neuropathy, sexual dysfunction and periodontal disease. Improvements in glycaemic control may help to reduce the risk of these complications. Several animal studies show that cinnamon may be effective in improving glycaemic control. While these effects have been explored in humans also, findings from these studies have not yet been systematically reviewed.
Objectives
To evaluate the effects of cinnamon in patients with diabetes mellitus.
Search methods
Pertinent randomised controlled trials were identified through AARP Ageline, AMED, AMI, BioMed Central gateway, CAM on PubMed, CINAHL, Dissertations Abstracts International, EMBASE, Health Source Nursing/Academic edition, International Pharmaceutical Abstracts, MEDLINE, Natural medicines comprehensive database, The Cochrane Library and TRIP database. Clinical trial registers and the reference lists of included trials were searched also (all up to January 2012). Content experts and manufacturers of cinnamon extracts were also contacted.
Selection criteria
All randomised controlled trials comparing the effects of orally administered monopreparations of cinnamon (Cinnamomum spp.) to placebo, active medication or no treatment in persons with either type 1 or type 2 diabetes mellitus.
Data collection and analysis
Two review authors independently selected trials, assessed risk of bias and trial quality, and extracted data. We contacted study authors for missing information.
Main results
Ten prospective, parallel‐group design, randomised controlled trials, involving a total of 577 participants with type 1 and type 2 diabetes mellitus, were identified. Risk of bias was high or unclear in all but two trials, which were assessed as having moderate risk of bias. Risk of bias in some domains was high in 50% of trials. Oral monopreparations of cinnamon (predominantly Cinnamomum cassia) were administered at a mean dose of 2 g daily, for a period ranging from 4 to 16 weeks. The effect of cinnamon on fasting blood glucose level was inconclusive. No statistically significant difference in glycosylated haemoglobin A1c (HbA1c), serum insulin or postprandial glucose was found between cinnamon and control groups. There were insufficient data to pool results for insulin sensitivity. No trials reported health‐related quality of life, morbidity, mortality or costs. Adverse reactions to oral cinnamon were infrequent and generally mild in nature.
Authors' conclusions
There is insufficient evidence to support the use of cinnamon for type 1 or type 2 diabetes mellitus. Further trials, which address the issues of allocation concealment and blinding, are now required. The inclusion of other important endpoints, such as health‐related quality of life, diabetes complications and costs, is also needed.
PICO
Plain language summary
Cimet za šećernu bolest
Šećerna bolest (lat. diabetes mellitus) je dugotrajna (kronična) bolest metabolizma. Oboljeli od dijabetesa imaju veći rizik od obolijevanja od srčano‐žilnih bolesti (uključujući srčani udar, moždani udar i perifernu bolest krvnih žila kao što je akutna ili kronična ishemija nogu koja uzrokuje intenzivnu bol prilikom čak i kratkog hodanja). Dijabetičari imaju veći rizik od očnih bolesti, zatajenja bubrega, oštećenja živaca i poremećaja seksualne funkcije, u usporedbi s općom populacijom. Poboljšanja regulacija šećera (glukoze) u krvi može pomoći u smanjenju rizika od tih komplikacija.
U brojnim istraživanjima provedenima na životinjama pokazalo se da kora drva cimetovca može poboljšati krvnu razinu šećera, iako učinak cimeta na šećer u krvi ljudi nije jasan. Stoga je napravljen Cochrane sustavni pregled da bi se utvrdilo imaju li ekstrakti cimeta kakav učinak na šećer u krvi ljudi i druge ishode. Autori su pronašli 10 randomiziranih kontroliranih pokusa u koje je bilo uključeno 577 ispitanika oboljelih od šećerne bolesti. Cimet su dobivali u obliku tableta ili kapsula, srednje doze 3 g dnevno, kroz 4‐16 tjedana. Studije općenito nisu bile dobro provedene i bile su loše kvalitete.
Autori sustavnog pregleda su analizom kliničkih pokusa o cimetu za liječenje dijabetičara utvrdili da cimet nije bolji od placeba, drugog aktivnog lijeka ili nikakvog liječenja za smanjenje razine glukoze u krvnoj plazmi i glikoziliranog hemoglobina A1c (HbA1c), koji predstavlja dugoročnu mjeru kontrole glukoze. Nijedno od pronađenih istraživanja nije analiziralo kvalitetu života vezanu za zdravlje, pobol, smrt od bilo kojeg uzroka ili troškove. Nuspojave na liječenje cimetom bile su općenito blage i rijetke.
Potrebna su daljnja istraživanja na temu dugoročnih koristi i rizika korištenja cimeta za liječenje šećerne bolesti. Buduće studije trebale bi imati rigorozan metodološki ustroj, kvalitetan prikaz metoda istraživanja i uzeti u obzir važne ishode kao što su kvaliteta života i komplikacije dijabetesa kao ključne informacije koje su nam potrebne.
