Abstract | Cilj istraživanja: Odrediti moždanu vazoreaktivnost u prednjoj i stražnjoj moždanoj cirkulaciji pomoću metode voljnog zadržavanja daha kod bolesnika s kroničnom opstruktivnom plućnom bolesti (KOPB) prema stupnju opstrukcije dišnog puta i moguću povezanost s totalnim antioksidativnim statusom (TAS) u plazmi. Nacrt studije: Presječno opservacijsko istraživanju u kojem je ispitanicima učinjena spirometrija, transkranijski dopler (TCD) i biokemijska analiza. KOPB ispitanici su podijeljeni prema forsiranom ekspiracijskom volumenu u prvoj sekundi (FEV1). Ispitanici i metode: Komparirano je 90 stabilnih KOPB ispitanika, bez prethodne cerebrovaskularne bolesti i 30 dobno- i spolno-usklađenih zdravih dobrovoljaca (srednja dob 67±7,9, 87 muškaraca). Koristeći TCD i indeks zadržavanja daha (BHI), analizirane su početne srednje brzine strujanja krvi (SBSK, m/s), srednji BHI (BHIm) u srednjoj cerebralnoj (ACM) i bazilarnoj arteriji (AB). Analiziran TAS u plazmi. Određena je statistička značajnost 0,05. Rezultati: KOPB ispitanici imali su nižu SBSK u ACM i AB te značajno niži BHImACM i BHImAB u odnosu na kontrole (0,8 i 0,7 odnosno 1,24 i 1,07; P<0,001). S težinom opstrukcije dišnog puta nađeno je značajno smanjenje BHImACM i BHImAB u blagoj (0,94 i 0,83), umjerenoj (0,8 i 0,7) i teškoj KOPB (0,7 i 0,6); P<0,001. Za sve ispitanike nađena je značajna pozitivna korelacija između FEV1 i BHImACM (Rho = 0,761, P<0,001) te između FEV1 i BHImAB (Rho = 0,409, P<0,001). TAS (mmol/L) bio je značajno viši u KOPB u odnosu na kontrole (1,68 [1,55 – 1,80] odnosno 1,59 [1,54 – 1,68]; P=0,03). U KOPB skupinama, nije bio značajne korelacije između FEV1 i TAS. U KOPB pušača, TAS je bio veći u teških pušača nego blagih, granične značajnosti. Samo u blagoj KOPB značajna je negativna korelacija između TAS i BHImAB (Rho = -0,445, P=0,01). Zaključak: KOPB ispitanici imaju oštećenu moždanu vazoreaktivnost u prednjoj i stražnjoj moždanoj cirkulaciji, koja se pogoršava s težinom bolesti. Moždana vazoreaktivnost prikladan je marker za identificiranje osjetljivih KOPB bolesnika s visokim rizikom razvoja cerebrovaskularne bolesti. TAS je značajno viši u KOPB ispitanika u odnosu na kontrole, ali ne ovisi o težini bolesti. Rezultati ne dopuštaju zaključak da je smanjena moždana vazoreaktivnost povezana sa sistemskim promjenama u antioksidativnom statusu bolesnika. Potrebne su prospektivne studije radi daljnje evaluacije. |
Abstract (english) | Objectives: The aim of the study was to quantify cerebrovascular vasoreactivity in anterior and posterior cerebral circulation with the voluntary breath holding method in chronic obstructive pulmonary disease (COPD) patients, according to airflow obstruction severity and possible relationship with total antioxidant status (TAS) in plasma. Study Design: This was a cross-sectional observational study in which the participants were instrumented with spirometry, transcranial doppler sonography (TCD) and biochemical analysis. COPD participants were divided according to forced expiratory volume in one second (FEV1). Participants and Methods: In the study 90 stable COPD patients without previous cerebrovascular disease were compared with 30 age- and sex- matched healthy volunteers (mean age 67±7.9, 87 males). The baseline mean flow velocities (MFV, m/s), mean BHI (BHIm) of middle cerebral artery (MCA) and basilar artery (BA) were analysed by means of using TCD and breath holding index (BHI). TAS was analysed in plasma. The level of statistical significance was set at 0.05. Results: COPD patients had lower baseline MFV of both MCA and BA and significantly lower BHIm MCA and BHIm BA than controls (0.8 and 0.7 versus 1.24 and 1.07, respectively; P<0.001). With the severity of airflow obstruction, there were significant declines of BHIm MCA and BHImBA in mild (0.94 and 0.83), moderate (0.8 and 0.7) and severe COPD (0.7 and 0.6), respectively (P<0.001). For all participants, a significant and positive correlation was found between forced expiratory volume in one second (FEV1) and BHImMCA (Rho= 0.761, P<0.001) and between FEV1 and BHImBA (Rho= 0.409, P<0.001). TAS was significant higher in COPD than controls (1.68 [1.55 − 1.80] versus 1.59 [1.54 − 1.68], respectively; P=0.03). In COPD groups, there was no significant correlation between FEV1 and TAS. In COPD smokers, TAS was higher in heavy smokers than light ones, but with boundary significance. Only in mild COPD group a significant negative correlation was found between TAS and BHImAB (Rho= -0,445, P=0,01). Conclusions: COPD patients have impaired cerebral vasoreactivity in anterior and posterior cerebral circulation, which increases with the airflow obstruction severity. Cerebral vasoreactivity is an appropriate marker to identify vulnerable COPD subjects at high risk to develop cerebrovascular disease. TAS was significant higher in stable COPD than controls, but there was no significant correlation between TAS and the airway obstruction severity. The results do not allow conclusions that decreased cerebral vasoreactivity is associated with systemic changes in antioxidant status of patients. Prospective studies are needed for further evaluation. |