Continuous Time Markov Chains for Analysis of Non Alcoholic Fatty liver Disease Evolution

Abstract In the present paper, the deleterious effects of obesity, type 2diabetes and insulin resistance, systolic and diastolic hypertension on the rate of progression of fibrosis in non-alcoholic fatty liver disease (NAFLD) patients are illustrated using a new approach utilizing the Poisson regression to model the transition rate matrix. The observed counts in the transition counts matrix are used as response variables and the covariates are the risk factors for fatty liver. Then the estimated counts from running the Poisson regression are used to estimate the transition rates using the continuous time Markov chains (CTMC) followed by exponentiation of the estimated rate matrix to obtain the transition probability matrix at specific time points. Using a hypothetical data of 150 participants followed up every year for a total of 28 years recording their demographic characteristics and their timeline of follow up are demonstrated. The findings revealed that insulin resistance expressed by MOMA-IR 2 has the most deleterious effects among other factors for increasing the rate of forward progression of patients from state 1 to state 2 as well as from state 2 to state 3 and from state 3 to state 4. The higher the level of HOMA-IR is, the more rapid the rate of progression is.

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Prognostic Factors for Evolution of Non Alcoholic Fatty Liver Disease Patients Utilizing Poisson Regression and Continuous Time Markov Chains

10.21203/rs.3.rs-1167621/v2 ◽

2021 ◽

Author(s):

Iman Mohamed Attia Abd-Elkhalik abo-elreesh

Keyword(s):

Insulin Resistance ◽

Fatty Liver ◽

Continuous Time ◽

Poisson Regression ◽

Fatty Liver Disease ◽

Rate Matrix ◽

Alcoholic Fatty Liver ◽

Continuous Time Markov Chains ◽

Rate Of Progression ◽

Alcoholic Fatty Liver Disease

Abstract In the present paper, the deleterious effects of obesity, type 2diabetes and insulin resistance, systolic and diastolic hypertension on the rate of progression of fibrosis in non-alcoholic fatty liver disease (NAFLD) patients are illustrated using a new approach utilizing the Poisson regression to model the transition rate matrix. The observed counts in the transition counts matrix are used as response variables and the covariates are the risk factors for fatty liver. Then the estimated counts from running the Poisson regression are used to estimate the transition rates using the continuous time Markov chains (CTMC) followed by exponentiation of the estimated rate matrix to obtain the transition probability matrix at specific time points. Using a hypothetical data of 150 participants followed up every year for a total of 28 years recording their demographic characteristics and their timeline of follow up are demonstrated. The findings revealed that insulin resistance expressed by MOMA-IR 2 has the most deleterious effects among other factors for increasing the rate of forward progression of patients from state 1 to state 2 as well as from state 2 to state 3 and from state 3 to state 4. The higher the level of HOMA-IR is, the more rapid the rate of progression is.

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Vitamin D levels are not associated with non-alcoholic fatty liver disease severity in a Brazilian population

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000667 ◽

2020 ◽

pp. 1-8

Author(s):

Jeniffer Danielle M. Dutra ◽

Quelson Coelho Lisboa ◽

Silvia Marinho Ferolla ◽

Carolina Martinelli M. L. Carvalho ◽

Camila Costa M. Mendes ◽

...

Keyword(s):

Vitamin D ◽

Liver Disease ◽

Fatty Liver ◽

Disease Severity ◽

Fatty Liver Disease ◽

Hypovitaminosis D ◽

Alcoholic Fatty Liver ◽

Vitamin D Levels ◽

The Mean ◽

Alcoholic Fatty Liver Disease

Abstract. Some epidemiological evidence suggests an inverse correlation between non-alcoholic fatty liver disease (NAFLD) frequency and vitamin D levels. Likewise, a beneficial effect of vitamin D on diabetes mellitus (DM) and insulin resistance has been observed, but this is an unsolved issue. Thus, we aimed to investigate the prevalence of hypovitaminosis D in a NAFLD Brazilian population and its association with disease severity and presence of comorbidities. In a cross-sectional study, the clinical, biochemical and histological parameters of 139 NAFLD patients were evaluated according to two different cut-off points of serum 25-hydroxyvitamin D levels (20 ng/mL and 30 ng/mL). The mean age of the population was 56 ± 16 years, most patients were female (83%), 72% had hypertension, 88% dyslipidemia, 46% DM, 98% central obesity, and 82% metabolic syndrome. Serum vitamin D levels were < 30 ng/mL in 78% of the patients, and < 20 ng/mL in 35%. The mean vitamin D level was 24.3 ± 6.8 ng/mL. The comparison between the clinical, biochemical and histological characteristics of the patients according to the levels of vitamin D showed no significant difference. Most patients with NAFLD had hypovitaminosis D, but low vitamin D levels were not related to disease severity and the presence of comorbidities.

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Non-Alcoholic Fatty Liver Disease in Overweight Children and its Relationship with Retinol Serum Levels

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.78.1.27 ◽

2008 ◽

Vol 78 (1) ◽

pp. 27-32 ◽

Cited By ~ 15

Author(s):

Suano de Souza ◽

Silverio Amancio ◽

Saccardo Sarni ◽

Sacchi Pitta ◽

Fernandes ◽

...

Keyword(s):

Insulin Resistance ◽

Liver Disease ◽

Fatty Liver ◽

Lipid Profile ◽

Fatty Liver Disease ◽

Thiobarbituric Acid ◽

Serum Levels ◽

Control Group ◽

Alcoholic Fatty Liver ◽

Alcoholic Fatty Liver Disease

Objectives: To evaluate the frequency of non-alcoholic fatty liver disease, the retinol serum levels, lipid profile, and insulin resistance in overweight/obese children. To relate these biochemical variables with the risk of this disease in the population studied. Methods: The study was cross-sectional and prospective, with 46 overweight/obese school children (28 female, 18 male; mean age 8.6 years). The control group consisted of 45 children, paired by age and gender. Hepatic steatosis, evaluated by ultrasound, was classified as normal, mild, moderate, or severe. Also evaluated were serum retinol levels; thiobarbituric acid reactive substances; lipid profile; and fasting glucose and serum insulin levels, used for the calculation of the Homeostasis Model Assessment. Results: Hepatic ultrasound alterations were found in 56.5% and 48,9% of the overweight/obese and control group children, respectively. Presence of obesity was associated with high levels of triglycerides (OR = 4.6; P = 0.002). In the studied children, the risk of steatosis was related to a trend to a higher percentage of retinol inadequacy (OR = 2.8; p = 0.051); there was no association with thiobarbituric acid reactive substances, lipid profile, or insulin resistance. Conclusions: The high frequency of non-alcoholic fatty liver disease in both groups, evaluated by hepatic ultrasound, in low-socioeconomic level children, independent of nutritional condition and without significant association with insulin resistance, emphasizes that especially in developing countries, other risk factors such as micronutrient deficiencies (e.g. vitamin A) are involved.

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