Aldosteron u metaboličkom sindromu

doctoral thesis

• Author: Ivan Pećin; MBZ: 340272
• Mentor: Željko Reiner (mentor)
• Committee member: nije dostupno (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; Zagreb
• Defense date and country: 2015-03-16, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences
• Universal decimal classification (UDC): 61 - Medical sciences

Abstract

Učestalost metaboličkog sindroma (MS) danas je u porastu u većini razvijenih zemalja. Brojne studije potvrđuju da je ukupni kardiovaskularni (KV) rizik povećan u osoba s MS iako ima i suprotnih rezultata. Neovisno o tome koji čimbenici sačinjavaju MS, u tih osoba prisutno je više poremećaja i čimbenika koji neovisno utječu na morbiditet i mortalitet. Do povećane učestalosti MS dolazi zbog stresa i povećane aktivnosti simpatikusa, prekomjernog unosa kalorija i premalo kretanja, te sve veće učestalosti visceralne pretilosti. Abdominalno masno tkivo nije samo mjesto pohrane energije nego i aktivan organ u kojem se sintetizira i luči čitav niz hormona i citokina koji pospješuju i ubrzavaju aterosklerozu, utječu na povećanje arterijskog tlaka, potiču upalu i izravno oštećuju ciljne organe. Dokazano je da se u visceralnim adipocitima sintetiziraju komponente renin-angiotenzin-aldosteronskog sustava. S druge strane, zadnjih desetljeća opažen je porast učestalosti primarnog aldosteronizma što se dijelom može objasniti boljom dijagnostikom, ali nije isključen niti izravan utjecaj slobodnih masnih kiselina na koru nadbubrežne žlijezde zbog sve češćeg MS. Uloga aldosterona u MS predmet je brojnih istraživanja. Zanimljivo, u bolesnika s primarnim hiperadosteronizmom uočena je veća učestalost metaboličkih poremećaja, a dokazano je da aldosteron pogoršava inzulinsku rezistenciju. Aldosteron nije povišen u svih bolesnika s MS što može ukazivati kako se mehanizam metaboličkog poremećaja, a time i kardiovaskularni rizik u tih bolesnika razlikuje. Cilj ovog istraživanja bio je odrediti prevalenciju MS u ruralnom kontinentalnom području Hrvatske i analizirati postoji li u bolesnika s MS razlika u čimbenicima kardiovaskularnog rizika i bubrežnog oštećenja ovisno o vrijednostima aldosterona.
Koristeći tri etablirane i najviše korištene definicije metaboličkog sindroma (NCEP-ATPIII, IDF i WHO) prevalencija metaboličkog sindroma u svih 1118 ispitanika uključenih u izradu ove disertacije iznosila 44.0%, 48.6% odnosno 20.3%. Premda ne postoji mnogo podataka o prevalenciji metaboličkog sindroma iz susjednih zemalja, trend sve veće prevalencije u svijetu je alarmantan. Koristeći u daljnjoj analizi NCEP-ATP III kriterije za definiranje metaboličkog sindroma nisu nađene značajne razlike u životnoj dobi između osoba koje su imale metabolički sindrom i skupine bez metaboličkog sindroma. MS je bio češći u osoba ženskog spola. Muškarci su kao najčešću komponentu MS imali hiperglikemiju i arterijsku hipertenziju, dok su žene češće imale patološki povećane vrijednosti opsega struka. Ispitanici s MS imaju češće kroničnu bubrežnu bolest te oštećenje ciljnih organa iskazano albuminurijom. Dnevni unos kuhinjske soli gotovo je dvostruko viši nego što je preporučeno (u obje ispitivane skupine). Nisu nađene statistički značajne razlike između serumske vrijednosti aldosterona u ispitanika s metaboličkim sindromom te u onih bez metaboličkog sindroma (prilagođeno za dob, spol i natriuriju; p=0.101).

Abstract (english)

The incidence of metabolic syndrome is now growing in most developed countries. Numerous studies confirm that the overall cardiovascular risk is increased in patients with MS. However, other authors have given conflicting results and failed to find connection between MS and CV risk. The metabolic syndrome is caused by stress and increased sympathetic activity, excessive intake of calories and lack of physical activity causing increased incidence of visceral obesity. Abdominal (visceral) fat is not only energy storage but also an active organ which synthesizes and secretes a number of hormones and cytokines that stimulate and accelerate atherosclerosis, affecting blood pressure, promote inflammation causing target organ damage. It has been shown that visceral adipocytes can synthesize components of the renin-angiotensin-aldosterone system. On the other hand, in last decade the increased prevalence of primary aldosteronism has been spotted. This can be explained by better diagnosis, but has not ruled out any direct effect of free fatty acids on the cortex of the adrenal gland. The role of aldosterone in MS is subject of numerous investigations. Interestingly, in patients with primary adosteronism a higher incidence of metabolic disorders was found, and evidence that aldosterone aggravates insulin resistance. Serum aldosterone was not elevated in all patients with MS which may indicate that the mechanisms of metabolic disorders, and therefore cardiovascular risk, in these patients are different. The aim of this study is to determine the prevalence of MS in a rural, inland Croatian territory and to analyze whether in patients with metabolic syndrome values of aldosterone influence the differences in cardiovascular risk factors and kidney damage.
Using most common 3 definitions of MS we found prevalence as follows: (NCEP-ATPIII, IDF and WHO) 44.0%, 48.6% and 20.3% respectively. The prevalence of metabolic syndrome in rural population is higher than expected. Recent data from neighbouring countries are sparse but still alarming. In further evaluation we used NCEP-ATPIII criteria in defining MS. We failed to find significant differences between compared groups according to age distribution. MS was more prevalent in females, and they had waist circumference value as the most prominent pathologic finding in defining MS. Males had hyperglycaemia and arterial hypertension. Examinees with MS had more often CKD and target organ damage according to higher prevalence of albuminuria. Salt consumption is two times higher than recommended. We failed to find significant differences in serum aldosterone concentrations between the two examined groups.

• Keywords: medicina
• Keywords (english): medicine
• Language: croatian
• URN:NBN: urn:nbn:hr:105:718691
• Study programme: Title: Biomedicine and Health Sciences; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstva (doktor/doktorica znanosti, područje biomedicine i zdravstva)
• Type of resource: Text
• Extent: 114 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-05-05 07:28:54