Okan Dikker

Dr. Okan Dikker

orcid

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

View All Publications
31 August 2023 in Children
Verified
Journal Article
Open access
PDF file
ODOkan Dikker
Okan Dikker
AAAyşe Aktaş
Ayşe Aktaş
MŞMustafa Şahin
Mustafa Şahin
MDMurat Doğan
Murat Doğan
HDHüseyi̇n Dağ
Hüseyi̇n Dağ
Background: Studies have shown that serum uric acid levels and uric acid-related ratios, such as uric acid-to-albumin ratio (UAR), uric acid-to-creatinine ratio (UCR), uric acid-to-high-density lipoprotein cholesterol (HDL cholesterol) ratio (UHR), and uric acid-to-lymphocyte ratio (ULR), are associated with various diseases and their complications, and that these ratios can be used as biomarkers. In the current study, we aimed to investigate uric acid levels in obese adolescents and the relationship of uric acid-related ratios with insulin resistance and obesity for the first time in the literature. Methods: A total of 100 adolescents (60 obese and 40 healthy) aged 10–17 years were retrospectively included. Participants were assigned to two groups: the obese group and the healthy control group. Obesity was defined as a body mass index (BMI) >the 95th percentile for age and gender. Demographic and laboratory data (serum glucose, urea, creatinine, uric acid, albumin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), C-reactive protein (CRP), total cholesterol, triglyceride, HDL cholesterol, thyroid-stimulating hormone (TSH), free T4 (fT4), insulin levels, and complete blood count) were obtained from the laboratory information management system. A homeostatic model of assessment for insulin resistance (HOMA-IR), low-density lipoprotein cholesterol (LDL cholesterol), and uric acid-related ratios were calculated. Results: Uric acid, UAR, UCR, and UHR levels of obese adolescents were significantly higher than the healthy group (p < 0.05). We found that HOMA-IR was positively correlated with uric acid, UAR, and UHR. No correlation was found between BMI and uric acid or uric acid-related ratios. We did not find any difference between the two groups in terms of ULR levels, and we did not find any correlation between BMI and HOMA-IR. Conclusion: High levels of serum uric acid, UAR, UCR, and UHR were associated with obesity. Furthermore, we found that uric acid, UAR, and UHR were positively correlated with insulin resistance.

29 March 2023 in Children
Verified
Journal Article
Open access
PDF file
HDHüseyi̇n Dağ
Hüseyi̇n Dağ
FIFatih İncirkuş
Fatih İncirkuş
ODOkan Dikker
Okan Dikker
Background: The atherogenic index of plasma (AIP) is the base-10 logarithmic conversion of the triglyceride to high-density lipoprotein cholesterol ratio [AIP = log10 (triglyceride/HDL cholesterol)]. Some studies have found a link between low serum vitamin D levels, AIP, and fatty liver. This study was conducted to evaluate the relationship between AIP levels, fatty liver, and vitamin D levels in obese adolescents aged 10–17 years. Methods: This study included 136 adolescents, including 83 obese and 53 healthy controls, in the age range of 10–17 years. Thirty-nine of the obese adolescents had fatty livers. Those with ultrasonography grades 2 or 3 of fat were in the fatty liver group. The AIP value was calculated as the logarithmic conversion of the ratio (triglyceride/HDL cholesterol) at the base of 10. Vitamin D and other laboratory tests were analyzed biochemically. Statistical evaluations were made with the SPSS program. Results: The AIP, body mass index (BMI), homeostatic model assessment for insulin resistance (HOMA-IR), and insulin averages of obese adolescents with fatty liver were significantly higher than those of obese adolescents without fatty liver and the healthy control group (p < 0.05). Again, the mean AIP of obese patients without fatty liver was pointedly higher than that of the healthy control group (p < 0.05). There was a positive, moderate relationship between AIP and BMI, AIP and HOMA-IR, and AIP and insulin levels (p < 0.05), whereas there was a negative, moderate (37.3%) relationship between AIP and vitamin D (p = 0.019). Conclusion: AIP levels were higher in obese adolescents, and this increase was higher in obese adolescents with fatty liver in this study. Moreover, we detected a negative correlation between AIP and vitamin D levels and a positive correlation with BMI, insulin resistance, and insulin levels. Based on our data, we concluded that AIP can be a useful predictor of fatty liver in obese adolescents.

11 November 2021 in Iberoamerican Journal of Medicine
Verified
Journal Article
Closed access
PDF file
ETEmine Türkkan
Emine Türkkan
NDNevin Çetin Dağ
Nevin Çetin Dağ
ÇAÇiğdem Arabacı
Çiğdem Arabacı
ODOkan Dikker
Okan Dikker
HDHüseyi̇n Dağ
Hüseyi̇n Dağ
Introduction: Obesity is a gradually more important multifactorial disease in both children and adults. Obese children and adolescents are at higher risk of becoming obese in adulthood, which is associated with an increased risk of mortality and morbidity. There is subclinical systemic inflammation in obesity. The study aimed to evaluate the hematological parameters as an indicator of inflammation in obese adolescents and to show the relationship of monocyte/HDL-cholesterol ratio, having a lipid component, with other inflammatory hematological parameters. Materials and methods: We retrospectively reviewed the medical files of 60 patients, 30 obese and 30 healthy controls, aged between 11 and 16 years, who applied to the pediatric outpatient clinic. Laboratory tests, hematological parameters, gender, age, and BMI were compared between the groups. Correlations between monocyte/HDL-cholesterol ratio and other laboratory parameters in the obese group were examined. Results: BMI, Alanine aminotransferase (ALT), C-reactive protein (CRP), triglyceride, insulin, and HOMA-IR levels of the obese adolescent group were statistically significantly higher than the control group (p0.05). There was no statistically significant relationship between monocyte/HDL-cholesterol and other inflammatory hematological rates (p>0.05). There was a positive, moderate (48.6%), and statistically significant relationship between monocyte/HDL-cholesterol and MLR (p<0.05). Conclusions: In our study, the NLR, PLR, MLR, and monocyte/HDL-cholesterol values of the obese adolescent group were similar to the control group. There was correlation between monocyte/HDL-cholesterol and monocyte/lymphocyte values. There was no correlation between other rates. Our data do not support the utility of inflammatory hematological rates as a biomarker in adolescent obesity. However, we believe that our study can shed light on other studies to be conducted.

8 November 2017 in Experimental and Clinical Endocrinology & Diabetes
Verified
Journal Article
Closed access
PDF file
ODOkan Dikker
Okan Dikker
SBSeldag Bekpinar
Seldag Bekpinar
GOGul Ozdemirler
Gul Ozdemirler
MUMujdat Uysal
Mujdat Uysal
MVMuberra Vardar
Muberra Vardar
BHBerrin Huner
Berrin Huner
Introduction Crosstalk between bone and adipose tissues is implicated in several pathologic conditions related to bone metabolism. Omentin-1, a 34-kD protein, is released from omental adipose tissue. A few studies indicated the effect of omentin-1 on bone health and bone mineral density (BMD) and the interaction of omentin-1 with vitamin D. Therefore, this study aimed to investigate the relationship between omentin-1, vitamin D, and BMD in postmenopausal women with osteoporosis compared with non-osteoporotic counterparts. Materials and methods Forty postmenopausal women with osteoporosis (OP), 40 counterparts without OP, and 30 premenopausal women were enrolled. Dual-energy X-ray Absorptiometry results, body mass index, and some demographic and biochemical data were recorded. Vitamin D (25-hydroxyvitamin D3) levels were measured using liquid chromatography-tandem mass spectrometry. Serum omentin-1 was determined using an enzyme-linked immunosorbent assay. Results Omentin-1 levels tended to increase in both postmenopausal women groups compared with the control group, but this increase was significant only in women with osteoporosis. Vitamin D levels were not different between the groups. When women were categorized according to vitamin D levels, women with normal vitamin D levels had significantly higher omentin-1 levels. A positive correlation was found between omentin-1 and vitamin D levels in all groups (r=0.197, p=0.041, n=110). Conclusion The tendency to an increase in omentin-1 levels in postmenopausal women with osteoporosis may be due to a physiologic compensation against bone loss after menopause. The linear relationship between omentin-1 and vitamin D suggests that adipose tissue is one of the target tissues for the vitamin D effect.

1 January 2020 in Cytokine
Verified
Journal Article
Closed access
ODOkan Dikker
Okan Dikker
NDNevin Çetin Dağ
Nevin Çetin Dağ
MŞMustafa Şahin
Mustafa Şahin
ETEmine Türkkan
Emine Türkkan
HDHüseyin Dağ
Hüseyin Dağ

1 March 2020 in The Journal of Pediatric Research
Verified
Journal Article
Closed access
HDHüseyi̇n Dağ
Hüseyi̇n Dağ
MKMelike Özberk Koç
Melike Özberk Koç
ODOkan Dikker
Okan Dikker
HDHasan Dursun
Hasan Dursun