Effect of Probiotics "Psychobiotics" on Depression and Metabolic Syndrome in Saudi Arabia

Primary Outcomes (7)

• Psychological Assessment (depression1)

  • Depression will be diagnosed clinically using the validated Arabic translated Patient Health Questionary 9 (PHQ-9) in Saudi population to assess the severity of depression as a self-report scale for patients in both groups. The minimum score is 0 while the maximum score is 27; the higher the score the more severe the depression is. Scores 0-4 means no depression; scores 5-9 means mild depression; scores 10-14 means moderate depression; score 15-19 means moderately severe, and 20-27 means severe depression.

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).

• Psychological Assessment (depression2)

  • Hamilton Depression Rating Scale (HDRS) will be also used as a clinician-rated scale to evaluate the severity of depression symptoms. The most commonly used versions in are either a 17- or a 21-item scale, but this study uses the 21-item scale. The scoring of the severity of the depressive symptoms is based on 17 items. It is scored between 0 (not present) and 4 (severe) points using either a three-point or a five-point scale and summed up to obtain the total score. Scores 0-7 represent the absence or remission of depression; scores between 8-16 represent mild depression; scores between 17-23 represent moderate depression, and scores equal to 24 and above represent severe depression.

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).

• Psychological Assessment (Anxiety)

  • Generalized Anxiety Disorder-7 (GAD-7) scale will be added to assess anxiety. Each of the 7 items is scored from 0 to 3, the GAD-7 scale score ranges from 0 to 21; the higher the score the more severe the anxiety is. Scores 0-4 means no anxiety; scores 5-9 means mild anxiety; scores 10-14 means moderate anxiety; score 15-21 means severe anxiety.

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).

• Anthropometric Measurements

  Height and weight will be combined to calculate the body mass index (BMI). BMI will be measured through dividing individual's weight in kilograms by height in square meter. Lower than 18.5 means underweight; 18.5 to lower than or equal 25 means normal weight; 25.0 to lower than or equal 30 means overweight; 30.0 or above means obese (Centers for Disease Control and Prevention (CDC), 2020).

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).

• Metabolic Syndrome Components (Waist circumference)

  Central obesity will be measured through waist circumference (WC) by placing non-stretchable meter around the waist above the bone of the hip equally; the tape should be tightened lightly without pressure on skin (Whitney \& Rolfes, 2020). WC for men is ≥ 94 centimeters while for women ≥ 80 centimeters (Alberti, Zimmet, \& Shaw, 2006).

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).

• Metabolic Syndrome Components (Medical Assessments/ Laboratory Tests)

  Blood samples will be collected out on venous blood after fasting for 12 h. Blood samples in each visit will be collected in 3 tubes and the value will be 3 ml in each tube. i. Fasting Plasma Glucose: pre-diabetic is more than 100 mg/dl to 125 mg/dl (Alberti, Zimmet, \& Shaw, 2006). ii. Hemoglobin A1C (HgA1C): pre-diabetic HbA1c is between 5.7 - 6.5% (Alberti, Zimmet, \& Shaw, 2006). iii. Triglycerides: more than 150 mg/dl (Alberti, Zimmet, \& Shaw, 2006). iv. High Density Lipoprotein-Cholesterol: less than 40 mg/dl in men and less than 50 mg/dl in women (Alberti, Zimmet, \& Shaw, 2006).

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).

• Metabolic Syndrome Components (Medical Assessments/ Blood Pressure)

  • Blood pressure for both groups will be measured three times sequentially at 1-min interval using the standardized method, the average between the three readings will be used as study variable (if more than 130 mmHg systolic BP/or more than 85 mmHg diastolic BP).

  at baseline, after the end of the 12th week of the intervention, and after 4 weeks post-intervention follow-up (end visit).