Investigation On The Adherence To Life Style Interventions For Patients With Nonalcoholic Fatty Liver Disease

Aim Nonalcoholic fatty liver disease(NAFLD) is the most common chronic liver disease in western countries, which accounting for twenty percent in general population and seventy to eighty percent among obese population. Life style interventions are important in NAFLD treatment, including increasing physical exercise and controlling diets. Although patients with NAFLD benefit a lot from life style intervention, the adherence to these interventions is undesirable. Cytokeratin-18(CK-18) is a kind of intermediate filament protein. Some studies suggested that serological level of CK-18 M30 could differentiate NASH from hepatic steatosis for it was associated with apoptosis. As a result, we aimed at evaluating NALFD patients’ adherence to life style interventions by developing Exercise and Dietary Adherence Scale(EDAS). In addition, we would further explore the relation between life style interventions and the changes in CK-18 M30 and between the changes and patients’ adherence.Methods This study was divided into two phases. In the first phase, we developed EDAS and evaluate the scale. In the second phase, included patients were provided of life style interventions and EDAS at baseline. Then the patients were followed up six months and were taken blood samples at each interview to test CK-18 M30 level.Results The self-development EDAS included thirty-three items in six dimensions, including Know and Care(including seven items), Beliefs(including four items), Dietary Self Control(including seven items), Physical Exercise Self Control(including five items), Dietary Control Restrictions(including three items) and Increasing Physical Exercise Restrictions(including seven items). The total score was 165, the higher the score, the better the adherence. Every item performed significant difference between the twenty-seven percent patients with the highest scores and thetwenty-seven percent patients with the lowest scores.(P<0.05) The retest reliability was 0.82 for one week intervals.(P<0.05) The internal consistency reliability of six dimensions were 0.739, 0.747, 0.771, 0.813, 0.791, 0.776 and 0.874, respectively. The Cronbach’s α coefficient was 0.874 for the total scale. The related coefficients between the dimensions in EDAS were from 0.050(between Know and Care and Increasing Physical Exercise Restrictions) to 0.624(Dietary Control Restrictions and Increasing Physical Exercise Restrictions), which did not suggest strong relations between dimensions. It was suggested that the total scores were associated with walk steps per day and decreasing calories intake per day when choosing the latter two indicators as criterions, with Pearson correlation coefficients 0.37 and 0.50 respectively. In addition, walk steps per day presented significant relations between Beliefs(r=0.29, P=0.020), Physical Exercise Self Control(r=0.40, P=0.001), Increasing Physical Exercise Restrictions(r=0.33, P=0.007). Decreasing calories intake per day were significant related to Beliefs(r=0.34, P=0.006), Dietary Self Control(r=0.64, P<0.001) and Dietary Control Restrictions(r=0.56, P<0.001). We extracted six common factors by confirmatory factor analysis, which explained 66.2% of the total variance. According to each factor loading level high to low, the six common factors could be explained by Dietary Control Restrictions, Know and Care, Beliefs, Dietary Self Control, Increasing Physical Exercise Restrictions and Physical Exercise Self Control. Then we extracted two common factors when reducing dimensions again, which explained 64.7% of the total variance. We denominated the first one as external conditions and the other one as internal motivations. In addition, the area under receiver operating curve(AUROC) were 0.613, 0.580,0.733,0.816 and 0.834 for the diagnosis of walk steps≥3000, ≥5000, ≥8000 and ≥10000 per day by EDAS, and the optimal cut-off points were 97.0, 99.0, 109.0, 109.0 and 113.0 respectively. Likewise, the AUROC were 0.646, 0.666, 0.774, 0.798 and 0.911 for the diagnosis of decreasing calories intake ≥50 kcal, ≥100 kcal, ≥200 kcal and ≥500 kcal per day, and the optimal cut-off points were102.0, 107.0, 108.0, 108.0 and 116.0 respectively. The changes of CK-18 M30 between the baseline and the sixth month ofinterview were significant associated with Dietary Self Control(rs=0.368, P=0.014), EDAS(rs=0.310, P=0.040), decreasing calories intake per day(rs=0.419, P=0.005) and weight loss in six months(rs=0.352, P=0.019).Conclusions EDAS presented preferable internal consistency reliability, retest reliability, content validity, construction validity and criterion validity. In clinical practice, patients who reached 116 scores of EDAS should be regarded to have good adherence to life style interventions, so dietary and exercise advice could be given first. For patients with soces between 97 and 115, which should be classified into fair adherence group, emphasis on life style interventions for them was more important. And drugs for hepatic inflammation were appropriate sometimes. At last, those who had scores of EDAS less than 97 should be considered to be poor adherent to life style interventions. As a result, drugs for hepatic inflammation as soon as possible were necessary. The changes of CK-18 M30 indicated that patients with stronger dietary self control presented more improvement in hepatic inflammation. Therefore, physicians should attach more importance on dietary control and closely observe weight changes when the liver functions were obvious abnormal. For patients with obvious hepatic inflammation and poor adherence to dietary control(EDAS scores less than 102), stronger drugs for liver injuries as early as possible were necessary.