This is a descriptive cross-sectional study conducted to evaluate the nutritional status and total antioxidant/oxidant capacity of individuals diagnosed with osteoarthritis.

The aim of this study is to determine the nutritional status of individuals diagnosed with osteoarthritis, to evaluate dietary total antioxidant/oxidant capacity and serum total antioxidant/oxidant capacity, and to examine the relationship of total antioxidant capacity with anthropometric measurements and nutritional status.

The study will include adult individuals diagnosed with osteoarthritis who applied to the Physical Therapy and Rehabilitation polyclinics of Ankara City Hospital. After the individuals fill out the questionnaire containing information about their socio-demographic characteristics, nutritional habits and physical activity levels, the researchers will take the food consumption records and the frequency of food consumption with a 24-hour reminder method. The total antioxidant amount of the diet will be determined from the food consumption records of the individuals. In addition to these, anthropometric measurements of individuals such as height, body weight and waist circumference will also be taken by the researchers.

In the study, routine biochemical parameter will be recorded from patient files and serum total antioxidant/oxidant capacity values will be examined.

The sample calculation was made using the Vanderbilt University Sample Calculation Tool, benefiting from the antioxidant capacity researches previously done in individuals with osteoarthritis in the literature. Assuming a standard deviation of ±20 in the study, the minimum sample size to be taken with 80% power and 5% error was determined as at least 47 people (case group) and 30 people (control group). In terms of the correct interpretation of the research results, the individuals in the case and control groups were similar in terms of age, gender and BMI in the selection of the sample (p≥0.05).

In the study, descriptive statistics (mean, lower value, upper value, standard deviation, standard deviation, mean) for data such as anthropometric measurements, daily consumption of food groups, energy and nutrient intakes, food consumption amounts and the rate of meeting the needs of energy and nutrients (%), number of meals. median) was calculated. The conformity of the variables to the normal distribution was examined using the Shapiro-Wilk test. Student's t test was used for the comparison of normally distributed variables in the groups (osteoarthritis diagnosis-control group), and the Mann-Whitney-U test was used for the comparison of non-normally distributed variables. In the comparison of more than two measurements, the Friedman test was used in cases where the normal distribution was not suitable. Correlations between numerical data were evaluated with the Pearson correlation test. The analyzes of the study were made in the SPSS 22.0 statistical package program and the statistical significance level was accepted as p<0.05.

Inclusion Criteria:

• Being between the ages of 18-65,
• Being followed up with a diagnosis of knee-osteoarthritis by doctor

Exclusion Criteria:

• Individuals under 18 and over 65 years of age,
• Individuals with acute or chronic inflammatory diseases,
• Individuals with chronic diseases,
• Individuals who consume alcohol,
• Smokers,
• Individuals who have not taken additional vitamin and mineral supplements in the last 6 months,
• Individualswho are not volunteer to participate in the study

Outpatient clinic patients