Mehmet Akif Karan
Istanbul University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Mehmet Akif Karan.
The Aging Male | 2010
Gulistan Bahat; Bulent Saka; Fatih Tufan; S. Akin; Süleyman Sivrikaya; Nurullah Yucel; Nilgun Erten; Mehmet Akif Karan
The prevalence of sarcopenia differs between different populations, ages, gender and between settings such as the community and nursing homes. Studies on the association of sarcopenia with functional status revealed conflicting results whereas its association with nutritional status is well documented. We aimed at investigating the prevalence of sarcopenia and its association with functional and nutritional status among male residents in a nursing home in Turkey. Fat free mass (FFM) was detected by bioelectric impedance analysis. Functional status was evaluated with Katz activities of daily living (ADL) and Lawton Instrumental activities of daily living (IADL). Nutritional assessment was performed by Mini Nutritional Assessment Test (MNA®). One hundred fifty-seven male residents composed the study cohort. Mean age was 73.1 ± 6.7 years. The prevalence of sarcopenia was 85.4%. No significant correlation was found between sarcopenia and ADL or IADL. There was a weak but significant correlation between IADL score and FFM (r = 0.18; p = 0.02). Sarcopenic residents had lower MNA score than non-sarcopenic residents (18.1 ± 3.2 vs. 21.8 ± 0.8, p = 0.02). FFM was significantly lower in the residents with malnutrition compared to well-nourished residents (26.8 ± 1 kg/body surface area vs. 28.1 ± 1.8 kg/body surface area, p < 0.05). In conclusion, the prevalence of sarcopenia was very high among male nursing home residents in Turkey. Sarcopenia was associated with low nutritional status but not with functional status.
Archives of Gerontology and Geriatrics | 2012
Gulistan Bahat; Fatih Tufan; Bulent Saka; S. Akin; H. Ozkaya; Nurullah Yucel; Nilgun Erten; Mehmet Akif Karan
BMI is commonly used indicator of malnutrition and 18.5-24.9 kg/m(2) is generally regarded optimal. However, there is an ongoing debate on ideal range for elderly. BMI cut-off values vary also between ethnic groups. We aimed to investigate relationships between BMI, functional status and malnutrition in elderly living in a nursing home in Turkey. BMIs of 254 residents were calculated. Chronic diseases and currently used drugs were noted. Functional status was evaluated with Katz-activities-of-daily-living (ADL) and Lawton-instrumental-activities-of-daily-living (IADL). Nutritional assessment was performed by Mini-Nutritional-Assessment (MNA) test. Mean age was 75.2 ± 8.2 years. Subjects were classified into 4 groups as BMI <18.5, 18.5-24.9, 25-29.9, and ≥ 30.0 kg/m(2). ADL scores and IADL scores were higher in higher BMI groups. There were no differences in terms of age-number of chronic diseases. Even in BMI ≥ 35 kg/m(2) residents, ADL was significantly higher than 25-34.9 kg/m(2) residents. BMI was significantly correlated with ADL and IADL scores. In Groups 3 and 4, there were 22.2% and 9.1% residents without normal nutrition, respectively. Better functional status was associated with higher BMI values even in BMIs ≥ 30 kg/m(2). In elderly, relative high rates of undernutrition may be present in BMIs regarded as overweight or obese.
Aging Clinical and Experimental Research | 2010
Gulistan Bahat; Bulent Saka; Nilgun Erten; Ugur Ozbek; Ender Coskunpinar; Safinaz Yildiz; Turker Sahinkaya; Mehmet Akif Karan
Background and aims: Sarcopenia is defined as a reduction in skeletal muscle mass, strength, and endurance observed with advancing age. Although Vitamin D receptor (VDR) polymorphism is reported to be associated with muscle mass and strength, evidence for this is limited and conflicting. In this study, we examined the association between the polymorphisms of VDR gene BsmI, TaqI and FokI and muscular mass and strength in elderly men. Methods: This is a cross-sectional study conducted in a university hospital. One hundred and twenty men over 65 years of age participated, all participants were active men living independently in Istanbul, who were followed as outpatients in geriatric polyclinics. Most common diagnoses were hypertension, hyperlipidemia, and mild to moderate osteoarthritis. Morbid obese patients were not included in the study. Genomic DNA was extracted from peripheral blood, and VDR genotypes were determined by the polymerase chain reaction. The peak torque of the knee flexors and extensors was measured on a Cybex 350 dynamometer. Body muscle mass was calculated by using bioelectric impedance analysis. Results: The extensor strength of the knee was higher in BB homozygotic men than in the Bb/bb group. No significant association was found with TaqI and FokI haplotypes. There was no significant association between muscle mass and strength, or between muscle mass and VDR genotype. Conclusion: Our data suggest that VDR gene BsmI polymorphism is associated with muscular strength in elderly men.
International Journal of Clinical Practice | 2005
Nilgun Erten; Bulent Saka; Y. K. Caliskan; Sevgi Kalayoglu Besisik; Mehmet Akif Karan; Cemil Tascioglu
A 73‐year‐old woman was presented with altered mental status and disorientation. She was diabetic and hypertensive, and she had experienced an ischemic cerebrovascular accident 3 years ago. Physical examination revealed the findings of chronic obstructive pulmonary disease, cor pulmonale and congestive heart failure. Hepatomegaly, splenomegaly and ascites were found and might be associated with postsinusoidal portal hypertension secondary to congestive heart failure. Laboratory tests showed uremia, lymphocytosis and thrombocytopenia. Neurologic findings were related with uremia and hypoxia. Multiple pathologic lymphadenopathies were seen in abdominal ultrasonography and thoracic computed tomography. Bone marrow histology indicated chronic lymphocytic leukaemia (CLL). The reason for acute renal failure was leukaemic infiltration of the kidneys due to CLL that was shown with renal biopsy. Blood urea nitrogen (BUN) and serum creatinine responded well to cyclophosphamide and methyl prednisolone treatment. In CLL, direct renal involvement is frequently seen in autopsy studies especially in advanced disease, however, renal failure due to leukaemic infiltration is extremely rare.
The Aging Male | 2014
Gulistan Bahat; Asli Tufan; H. Ozkaya; Fatih Tufan; Timur Selcuk Akpinar; S. Akin; Zumrut Bahat; Zuleyha Kaya; Esen Kiyan; Nilgun Erten; Mehmet Akif Karan
Abstract Adverse-outcomes related to sarcopenia are mostly mentioned as physical disability. As the other skeletal muscles, respiratory muscles may also be affected by sarcopenia. Respiratory muscle strength is known to affect pulmonary functions. Therefore, we aimed to investigate the relations between extremity muscle strength, respiratory muscle strengths and spirometric measures in a group of male nursing home residents. Among a total of 104 male residents, residents with obstructive measures were excluded and final study population was composed of 62 residents. Mean age was 70.5 ± 6.7 years, body mass index: 27.7 ± 5.3 kg/m2 and dominant hand grip strength: 29.7 ± 6.5 kg. Hand grip strength was positively correlated with maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) (r = 0.35, p < 0.01 and r = 0.26, p < 0.05, respectively). In regression analysis, the only factor related to MIP was hand grip strength; among spirometric measures only parameter significantly related to grip strength was peak cough flow (PCF). The association of PCF with grip strength disappeared when MIP alone or “MIP and MEP” were included in the regression analysis. In the latter case, PCF was significantly associated only with MIP. We found peripheric muscle strength be associated with MIP and PCF but not with MEP or any other spirometric parameters. The relation between peripheral muscle strength and PCF was mediated by MIP. Our findings suggest that sarcopenia may affect inspiratory muscle strength earlier or more than the expiratory muscle strength. Sarcopenia may cause decrease in PCF in the elderly, which may stand for some common adverse respiratory complications.
International Journal of Clinical Practice | 2005
Nilgun Erten; Bulent Saka; Gulistan Bahat Ozturk; Mehmet Akif Karan; Cemil Tascioglu; M. Dilmener; Abdulkadir Kaysi
Fever of unknown origin (FUO) is defined as the body temperature higher than 38.3 °C on several occasions and lasting longer than 3 weeks, with the aetiology remaining uncertain after 1 week of investigation. In this study, we reviewed 57 patients with FUO hospitalised in our inpatient department between 1998 and 2003. The median age of the patients was 44 years (17–84), and 26 were males (46%), while 31 were females (54%). In 24 patients (42%), infectious diseases such as tuberculosis (12 patients) and brucellosis (5 patients) were found under the aetiology of FUO. Inflammatory rheumatic diseases were the second most common cause of FUO (17 patients, 30%), while malignancies were found in 10 patients (18%). In six patients (10%), aetiology could not be identified. In conclusion, infectious diseases especially tuberculosis and brucellosis are the leading causes of FUO in our country.
Geriatrics & Gerontology International | 2017
Gulistan Bahat; Ilker Bay; Asli Tufan; Fatih Tufan; C. Kilic; Mehmet Akif Karan
To date, there is no study comparing the Beers 2012 and Screening Tool of Older Persons Prescriptions (STOPP) version 2 criteria, nor reporting a comparison of the prevalence of potentially inappropriate Prescribing (PIM) with STOPP version 2. We aimed to evaluate the prescriptions of patients admitted to a geriatric outpatient clinic with these tools, and to document the factors related to PIM use.
Revista De Nutricao-brazilian Journal of Nutrition | 2011
Bulent Saka; Gulistan Bahat Ozturk; Sami Uzun; Nilgun Erten; Sema Genc; Mehmet Akif Karan; Cemil Tascioglu; Abdulkadir Kaysi
OBJETIVO: Falha no reconhecimento e acompanhamento do estado nutricional e a razao mais importante da desnutricao em pacientes hospitalizados. Este estudo objetivou avaliar o estado nutricional dos pacientes e comparar os resultados com os niveis sericos de pre-albumina. METODOS: Foram incluidos 97 pacientes no estudo, internados consecutivamente. O risco de desnutricao foi avaliado de acordo com dados antropometricos e com a Avaliacao Subjetiva Global e Triagem de Risco Nutricional 2002. Os estados nutricionais dos pacientes foram comparados com suas idades, sexo, indice de massa corporal, historico medico, perda de peso e analises bioquimicas, incluindo pre-albumina e tempo de permanencia hospitalar. RESULTADOS: De acordo com o Triagem de Risco Nutricional 2002, 57% dos pacientes estavam desnutridos ou em risco de desnutricao, apresentando boa correlacao com o Avaliacao Subjetiva Global (p<0,001, r=0,700). A analise multivariada mostrou correlacoes positivas entre desnutricao e idade, perda de peso, malignidade e proteina reativa-C (p=0,046, p=0,001, p=0,04 e p=0,002). Um escore ³3 no Triagem de Risco Nutricional 2002 foi associado a internacao prolongada (p<0,001). Houve correlacao entre pre-albumina serica e o estado nutricional, independente do numero de doencas cronicas e biomarcadores de inflamacao (p=0,01). A sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e valor diagnostico da pre-albumina na avaliacao do risco de desnutricao foram de 94%, 32%, 0,67, 0,78 e 69, respectivamente. Apos sete dias de suporte nutricional, o risco de desnutricao caiu em 12% (p<0,001) e os niveis sericos de pre-albumina aumentaram em 20% (p=0,003). CONCLUSAO: Ao inves de refletir o estado nutricional global do paciente, niveis sericos baixos de sericos de pre-albumina podem ser vistos como um sinal de maior risco de desnutricao, exigindo uma avaliacao nutricional mais extensa. A analise serica de pre-albumina pode ser usada para o monitoramento de pacientes recebendo suporte nutricional.
The Aging Male | 2013
Gulistan Bahat; Fatih Tufan; Zumrut Bahat; Yucel Aydin; Asli Tufan; Timur Selcuk Akpinar; Nilgun Erten; Mehmet Akif Karan
Abstract Functionality, comorbidities, polypharmacy, nutritional status and sarcopenia affect the prognosis of elderly excessively. These parameters are influenced by the population, living settings and age. We aimed to study these parameters in Turkish community-dwelling male elderly. We studied 274 male elderly ≥60 years of age admitted to our Geriatrics outpatient clinics. Mean age was 74.4 ± 7.1 years; 47.4% of the subjects were ≥75 years, 24.1% were ≥80 years. Mean activities-of-daily-living (ADL) and instrumental ADL (IADL) scores were 9.4 and 11.1, respectively. Patients with at least one-dependence at ADL–IADL were 22.6%–47.2%, and more than half-dependence at ADL–IADL were 2.8%–17.9%, respectively. Mean number of comorbidities were 2.6. Most common diagnosis was hypertension with 65%; mean number of drugs were 4.5; 55.3% were using ≥4 chronic drugs. Prevalences of malnutrition were 3.7%–6.9%, malnutrition risk were 23.5%–26.7% by the Mini Nutritional Assessment Test - Long Form and Short Form, respectively. Calf circumference was measured <31 cm in 10.5%. Our findings suggest that Turkish community-dwelling male elderly may have greater prevalences of functional dependence, sarcopenia but lower rates of malnutrition and similar rates of polypharmacy compared with the western developing countries and developed countries. This study emphasized the geographical differences in and/or between the individual countries highlighting the need for studies both country- and world-wide.
Acta Histochemica | 2015
H. Kübra Elçioğlu; Levent Kabasakal; Fatih Tufan; Ömer H. Elçioğlu; Seyhun Solakoglu; Tuğba Kotil; Mehmet Akif Karan
Tumor necrosis factor-alpha (TNF-α) upregulation enhances amyloid β (Aβ) induced neurotoxicity in Alzheimers disease (AD). Intracerebroventricular streptozotocin (STZ) administration causes pathological changes and cognitive deficits similar to those seen in AD by causing impairment of brain glucose and energy metabolism. Recent reports indicate a protective role of Thalidomide, Etanercept, and Infliximab, all of which have anti-TNF-α activity, against cognitive and neuropathological changes in experimental and clinical studies. We aimed to investigate the protective effects of Thalidomide, Etanercept, and Infliximab in a rat model of intracerebroventricular STZ-induced dementia. Sprague-Dawley rats (250-300g) were separated to sham (n=6) and STZ (n=24) groups. The STZ group was divided into four groups (STZ, STZ-thalidomide, STZ-etanercept, and STZ-infliximab). Morriss water maze (MWM) and passive avoidance (PA) tests were performed. At the end of the third week, brain tissues were obtained. Histopathological analysis, immunohistochemistry, and electron microscopic examinations were done. The improvement performance of the STZ group was significantly reduced in the MWM test (p<0.001). Compared with the STZ, STZ-thalidomide, STZ-etanercept, and STZ-infliximab groups had significantly better performance (p<0.001, <0.05 and <0.05, respectively) in the MWM test. STZ administration caused a significant decrease in the mean escape latency in PA reflex (p<0.001). Thalidomide, Etanercept, and Infliximab were associated with better PA reflexes compared to the STZ group (p<0.001 for all). Morphological and immunohistochemical results showed increased neurodegenerative changes compared to sham group. Our findings are in line with the findings reported in the literature and encourage further studies with TNF-α antagonists, in particular Thalidomide.