Nikolaos D. Karakousis

Dr. Nikolaos D. Karakousis

University of Thessaly, Larissa, Greece
orcid
Dr. - Internal Medicine Physician, Teaching Assistant

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 September 2020 in Liver International
Verified
Journal Article
Open access
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Nikolaos D. KarakousisNikolaos D. Karakousis
Nikolaos D. Karakousis
APAlkistis Papatheodoridi
Alkistis Papatheodoridi
ACAntonios Chatzigeorgiou
Antonios Chatzigeorgiou
George PapatheodoridisGeorge Papatheodoridis
George Papatheodoridis
Chronic hepatitis B is mainly responsible for the morbidity and mortality from hepatitis B virus (HBV)‐related complications, including hepatocellular carcinoma (HCC) and decompensated cirrhosis. Hepatocellular carcinoma remains the main challenge in the management of not only undiagnosed and/or untreated but also diagnosed and treated patients with chronic HBV infection, as its incidence decreases but is not eliminated even after many years of effective anti‐HBV therapy. The exact mechanisms used by HBV to cause malignant transformation remain uncertain, although much of the available data are in favour of a pathogenetic role of HBx protein. Senescence is a cellular state, in which cells lose their ability to proliferate. This biological mechanism may function in a dual mode, namely being both cancer‐protective as a result of reduced cellular proliferation, but also cancer‐enhancing as a result of modulation of the tissular microenvironment by immune cells during persistent accumulation of senescent cells. Protein X of HBV protein exhibits many similarities in terms of the implemented mechanisms of action and pathways related to the biological process of cellular senescence. Concurrently, insufficient clearance of both senescent and precancerous hepatocytes combined with inadequate immune surveillance as a result of immunosenescence caused by chronic HBV infection may lead to hepatocarcinogenesis. Thus, the effect of HBV seems to be critical as a connecting link between cellular senescence and development of HCC. An ongoing research is underway towards identifying and validating markers of hepatocyte senescence, which could improve the landscape for evaluation of chronic liver disease, thereby providing valuable information in terms of HBV‐related carcinogenesis.

1 September 2020 in Journal of Frailty, Sarcopenia and Falls
Verified
Journal Article
Open access
NKNikolaos Kostakopoulos
Nikolaos Kostakopoulos
Nikolaos D. KarakousisNikolaos D. Karakousis
Nikolaos D. Karakousis
Major urologic oncology procedures such as radical cystectomy (RC), radical prostatectomy (RP), radical nephroureterectomy (RNU) and radical or partial nephrectomy are the gold standard operations for the treatment of urological malignancies not suitable to be dealt with using minimal invasive procedures such as transurethral resection or other conservative approaches. However, these surgical procedures carry significant risk of complications, especially in elderly and frail patients. The purpose of this review is to highlight the use of a wide variety of preoperative frailty and health status indexes and calculators. Recent data from large population based studies confirm that these calculators can assist physicians and urologists to predict the postoperative morbidity of patients undergoing major operations. Moreover, these frailty calculators can help urologists choose the most suitable and safe treatment for every individual patient. However, the absence of widely accepted specific urologic oncology calculators to predict the association between frailty and postoperative complications emphasizes the necessity for the use of a combination of calculators.

1 March 2022 in Journal of Frailty, Sarcopenia and Falls
Verified
Journal Article
Open access
EPElisavet E. Pyrgioti
Elisavet E. Pyrgioti
Nikolaos D. KarakousisNikolaos D. Karakousis
Nikolaos D. Karakousis
Vitamin B12, widely known as cobalamin, is a water-soluble vitamin crucial for human metabolism. It is synthesized only by prokaryotic organisms and since humans do not have the ability to synthesize it, they rely on its exogenous dietary intake. After its consumption, vitamin B12 undergoes a complicated procedure of absorption and assimilation and it is essential for cellular function, especially for nervous system, red blood cell production and DNA synthesis. Deficiency of vitamin B12 is considered as an important public health issue worldwide, while it is common in the elderly. Deficiency of this vitamin, as well as high levels, indicate a risk factor for morbidity with various clinical manifestations. Frailty is an age-related syndrome, which affects the elderly and is characterized by decreased function in many physiological systems, accompanied by vulnerability to stressors. A narrative non-systematic mini review of the literature was conducted and highlighted that vitamin B12 levels may have an impact on frailty and vice versa. As shown in several studies, vitamin B12 levels may be related to sarcopenia, cognitive and musculoskeletal disorders, neurological or psychiatric symptoms, which are closely linked to frailty. Furthermore, it is suggested that the extensions of frailty may affect the bioavailability of vitamin B12.

28 January 2025 in Clinical Transplantation
Verified
Journal Article
Open access
GMGeorge E. Markakis
George E. Markakis
JLJennifer C. Lai
Jennifer C. Lai
Nikolaos D. KarakousisNikolaos D. Karakousis
Nikolaos D. Karakousis
George PapatheodoridisGeorge Papatheodoridis
George Papatheodoridis
TPTheodora Psaltopoulou
Theodora Psaltopoulou
EVANGELOS CHOLOGKITASEVANGELOS CHOLOGKITAS
EVANGELOS CHOLOGKITAS
Introduction: This systematic review/meta‐analysis evaluated the impact of sarcopenia in patients with cirrhosis before liver transplantation (LT) on outcomes after LT.Methods: A systematic search was conducted in six medical databases until February 2022. The primary outcome was overall mortality after LT, while several secondary outcomes including liver graft survival and rejection, the need for transfusions, the length of the intensive care unit (ICU) and hospital stay, and surgical complications were evaluated. Sub‐group analyses and meta‐regression analyses were also performed.Results: Fifty‐three studies were evaluated in the systematic review, of which 30, including 5875 patients, were included in the meta‐analysis. All studies included were cohort studies of good/high quality on the Newcastle‐Ottawa scale (NOS), while in our analysis no publication bias was found, although there was substantial heterogeneity between the studies. Muscle mass was assessed using skeletal muscle index (SMI) in 14 studies, psoas muscle area (PMA) in seven studies, and psoas muscle index (PMI) in four studies. The prevalence of pre‐LT sarcopenia ranged from 14.7% to 88.3%. Pre‐LT sarcopenia was significantly associated with post‐LT mortality (Relative Risk [RR] = 1.84, 95% CI:1.41,2.39), as well as with a high risk of infections post‐LT, surgical complications, fresh frozen plasma (FFP) transfusions, and ICU length of stay (LOS).Conclusions: Pre‐LT sarcopenia in patients with cirrhosis is a strong risk factor for clinically meaningful adverse outcomes after LT. Assessment may help identify patients at the highest risk for poor outcomes who may benefit from targeted interventions.

1 March 2021 in Journal of Frailty, Sarcopenia and Falls
Verified
Journal Article
Open access
NKNikolaos Kostakopoulos
Nikolaos Kostakopoulos
Nikolaos D. KarakousisNikolaos D. Karakousis
Nikolaos D. Karakousis
DMDimitrios Moschotzopoulos
Dimitrios Moschotzopoulos
This review summarizes the current literature on the correlation between frailty and urinary tract infections (UTIs), as well as the potential causes and measures that can be taken to prevent and treat these frailty associated UTIs (FaUTIs). A narrative review of the literature was carried out using the keywords and other associated terms (catheter associated UTIs and frailty, causes of UTIs, prevention of UTIs in the frail, treatment of UTIs in the frail). As it is shown in the literature, many risk factors that are associated with frailty such as dehydration, reduced mobility and cognitive impairment, as well as other anatomical or functional abnormalities can make frail patients prone to UTIs that are also more difficult to treat. Early correction of these risk factors (for example avoiding long term catheters, increasing hydration, treating lower urinary tract obstruction or incontinence), can prevent UTIs and improve the quality of life of frail patients. Prompt and individualized antimicrobial treatment of UTIs in the frail population can result in decreasing mortality rates but also minimize unnecessary antimicrobial drug use.

5 July 2022 in The International Journal of Lower Extremity Wounds
Verified
Journal Article
Closed access
Nikolaos D. KarakousisNikolaos D. Karakousis
Nikolaos D. Karakousis
EPElisavet E. Pyrgioti
Elisavet E. Pyrgioti
PGPetros N. Georgakopoulos
Petros N. Georgakopoulos
Nikolaos PapanasNikolaos Papanas
Nikolaos Papanas
The aim of this narrative mini review was to investigate the potential association of the diabetic foot (DF) with sarcopenia and frailty. Data is still limited, but it appears that DF patients may be more prone to frailty. In addition, patients with DF and sarcopenia exhibit more frequently foot ulcers and amputations, as well as increased mortality rates post-operatively. Further studies are now needed to see how these realizations may be used in clinical practice, aiming to improve DF outcomes.