NUTRITION IN HEALTH AND DISEASE
LECTURE 1: INTRODUCTION AND INSTRUCTIONS ASSIGMENT 1
Basic concepts / physiology:
- (Patho)physiology GI tract
- Body composition
- Nutritional requirements (energy/protein)
Specific situations:
- Development/Treatment of (chronic) disease
- Malnutrition
- EN, TPN, Refeeding
- Sports
Clinical nutrition: nutritional care for individual patients or patient groups.
Public health nutrition: health control and prevention of disease.
Course objectives:
1. To reason the role of nutrition and optimal protein and energy requirements and the consequences of
malnutrition in different populations, including early life, disease and sports.
2. To critically evaluate (clinical) studies on the influence of dietary patterns and specific nutrients on the
development of (chronic) diseases and the influence of (chronic) diseases on nutritional status, with
regard to research design, patient selection, methods and selected outcomes.
3. To be able to perform and interpret measurements to determine body composition and to value the
validity and suitability of different methods in scientific research and clinical practice and to be able to
pitch this for an audience of peers and teachers.
4. To be able to design a scientific research proposal for a clinical study, considering the rules and
(ethical) regulations of clinical (nutrition) research and applying the above mentioned knowledge.
Body composition:
- Nutritional treatment is mainly focused on maintaining FFM
- Techniques have assumptions and limitations
- Vary measurement conditions (water)
- Bodpod and BIA
,LECTURE 2: RULES AND REGULATIONS
The preparation phase of clinical research from A-Z with extra attention to rules, regulations and ethics.
Where do you start when you would like to start a (clinical nutrition) research project?
RESEARCH QUESTION
Background:
- Known:
o Broad context
o Clinical / social relevance
o What is already known about this topic
- Unknown:
o Scientific relevance: GAP
o Research question
o Hypothesis
o Study design, which will lead to your research proposal
Keep in mind that every research has a budget:
- Salary
- Equipment
- Laboratory costs
- Education
- Office equipment
- Travel costs of participants
You can apply for a grant via health insurance companies or medical nutrition industry.
What to do before you can start?
- Write protocol
- Present protocol to departments involved
- Prepare protocol and other files for Scientific Research Committee
- Prepare protocol and other files for Medical Research Ethical Committee (MREC / METC)
- Prepare logistics
Work out the research question using PICO
- P: population
- I: intervention
- C: comparison
- O: outcome
Select your study population by using inclusion and exclusion criteria.
You can describe your chosen study design by using a flowchart.
Sample size calculation:
,Why do we use this calculation?
- If n is too small, there will be a false negative conclusion
- If n is too large:
o Intervention effective: too many subjects have missed out on this intervention
o Intervention ineffective: too many subjects have been exposed to this ineffective intervention
What information de we need for the sample size calculation?
- Desired power of the study: 80% is accepting a chance of 20% of failing to detect an effect that is
indeed present in the population.
o How certain do you want to be of preventing a type 2 error?
o False negative
- Desired significance level: 5% is accepting a chance of 0.05 to detect an effect in your study that is not
present in the whole population.
o How certain do you want to be of preventing a type 1 error?
o False positive
- Desired test direction: one or two sided?
o 2-sided: treatment A better than treatment B // treatment B better than treatment A
- Clinically relevant (or expected) difference: from literature.
o Which difference or which effect are you trying to find?
- Expected variance / standard deviation: from pilot data or literature.
o How much variation is expected in subjects belonging to the same study group?
- Attrition rate: expected drop-out / withdrawal from previous studies. If 10% drop-out is expected,
divide the number needed by 0.9.
o Anticipate on the number of included subjects who will not be available for the study
analysis.
Type 1 error (alpha): the probability of false rejecting H0
Type 2 error (beta): the probability of false accepting H0
Differences in means:
- Difference in body weight change between groups
- Difference in survival time between groups
Difference in proportions:
- Difference in proportions (%) with a certain weight loss between groups
- Difference in proportions (%) 1 year survival between groups
Ethical and practical considerations:
- It is NOT always ethical to have a control group
- You can NOT call a patient to ask if he/she wants to participate
- You need to arrange an insurance
WMO: Wet Medisch-wetenschappelijk Onderzoek met mensen.
Research is subject to the WMO if the following criteria are met:
, 1. It concerns medical scientific research
2. Participants are subject to procedures or are required to follow rules of behavior
• Infringement of the physical and/or psychological integrity of the subject
• Subject himself/herself must be physically involved in in the research
WMO or NOT-WMO?
Time line of the study approval is approximately 6 months:
- First committee: department
- Second committee: committee of scientific research
- Third committee: MREC
What to do next?
- Make an investigator site file with all important research documents
- Make Case Report Forms (CRF) for writing down the data
- Set up a database
- Make arrangements with the involved deparmtents on the measurements planned
- Paperwok
- Training of staff
- Etc…
Kick Off meeting:
- Goal: to know tasks and responsibilities for every person involved.
- How: discuss every step in the way from recruitment of a patient until the last visit.
Function of the monitoring board:
- Check of the progress of the study
- Quality check in random test of recruited patients:
o Informed consent
o In- and exclusion of criteria
o Source data verification
o Protocol violations
o Check of serious adverse events
- Goal: guarding safety of patients and quality of research
Declaration of Helsinki:
- Good Clinical Practice (GCP)
- Goals GCP and Declaration of Helsinki:
o Protection of humans (ethical principles, protection of personal information, safety
procedures, etc.)
o Standard for quality of research
Why do we have all these rules, laws, directives? Why do we need monitoring?
- Unethical medical experiments in minorities
- Fraude – falsification
LECTURE 1: INTRODUCTION AND INSTRUCTIONS ASSIGMENT 1
Basic concepts / physiology:
- (Patho)physiology GI tract
- Body composition
- Nutritional requirements (energy/protein)
Specific situations:
- Development/Treatment of (chronic) disease
- Malnutrition
- EN, TPN, Refeeding
- Sports
Clinical nutrition: nutritional care for individual patients or patient groups.
Public health nutrition: health control and prevention of disease.
Course objectives:
1. To reason the role of nutrition and optimal protein and energy requirements and the consequences of
malnutrition in different populations, including early life, disease and sports.
2. To critically evaluate (clinical) studies on the influence of dietary patterns and specific nutrients on the
development of (chronic) diseases and the influence of (chronic) diseases on nutritional status, with
regard to research design, patient selection, methods and selected outcomes.
3. To be able to perform and interpret measurements to determine body composition and to value the
validity and suitability of different methods in scientific research and clinical practice and to be able to
pitch this for an audience of peers and teachers.
4. To be able to design a scientific research proposal for a clinical study, considering the rules and
(ethical) regulations of clinical (nutrition) research and applying the above mentioned knowledge.
Body composition:
- Nutritional treatment is mainly focused on maintaining FFM
- Techniques have assumptions and limitations
- Vary measurement conditions (water)
- Bodpod and BIA
,LECTURE 2: RULES AND REGULATIONS
The preparation phase of clinical research from A-Z with extra attention to rules, regulations and ethics.
Where do you start when you would like to start a (clinical nutrition) research project?
RESEARCH QUESTION
Background:
- Known:
o Broad context
o Clinical / social relevance
o What is already known about this topic
- Unknown:
o Scientific relevance: GAP
o Research question
o Hypothesis
o Study design, which will lead to your research proposal
Keep in mind that every research has a budget:
- Salary
- Equipment
- Laboratory costs
- Education
- Office equipment
- Travel costs of participants
You can apply for a grant via health insurance companies or medical nutrition industry.
What to do before you can start?
- Write protocol
- Present protocol to departments involved
- Prepare protocol and other files for Scientific Research Committee
- Prepare protocol and other files for Medical Research Ethical Committee (MREC / METC)
- Prepare logistics
Work out the research question using PICO
- P: population
- I: intervention
- C: comparison
- O: outcome
Select your study population by using inclusion and exclusion criteria.
You can describe your chosen study design by using a flowchart.
Sample size calculation:
,Why do we use this calculation?
- If n is too small, there will be a false negative conclusion
- If n is too large:
o Intervention effective: too many subjects have missed out on this intervention
o Intervention ineffective: too many subjects have been exposed to this ineffective intervention
What information de we need for the sample size calculation?
- Desired power of the study: 80% is accepting a chance of 20% of failing to detect an effect that is
indeed present in the population.
o How certain do you want to be of preventing a type 2 error?
o False negative
- Desired significance level: 5% is accepting a chance of 0.05 to detect an effect in your study that is not
present in the whole population.
o How certain do you want to be of preventing a type 1 error?
o False positive
- Desired test direction: one or two sided?
o 2-sided: treatment A better than treatment B // treatment B better than treatment A
- Clinically relevant (or expected) difference: from literature.
o Which difference or which effect are you trying to find?
- Expected variance / standard deviation: from pilot data or literature.
o How much variation is expected in subjects belonging to the same study group?
- Attrition rate: expected drop-out / withdrawal from previous studies. If 10% drop-out is expected,
divide the number needed by 0.9.
o Anticipate on the number of included subjects who will not be available for the study
analysis.
Type 1 error (alpha): the probability of false rejecting H0
Type 2 error (beta): the probability of false accepting H0
Differences in means:
- Difference in body weight change between groups
- Difference in survival time between groups
Difference in proportions:
- Difference in proportions (%) with a certain weight loss between groups
- Difference in proportions (%) 1 year survival between groups
Ethical and practical considerations:
- It is NOT always ethical to have a control group
- You can NOT call a patient to ask if he/she wants to participate
- You need to arrange an insurance
WMO: Wet Medisch-wetenschappelijk Onderzoek met mensen.
Research is subject to the WMO if the following criteria are met:
, 1. It concerns medical scientific research
2. Participants are subject to procedures or are required to follow rules of behavior
• Infringement of the physical and/or psychological integrity of the subject
• Subject himself/herself must be physically involved in in the research
WMO or NOT-WMO?
Time line of the study approval is approximately 6 months:
- First committee: department
- Second committee: committee of scientific research
- Third committee: MREC
What to do next?
- Make an investigator site file with all important research documents
- Make Case Report Forms (CRF) for writing down the data
- Set up a database
- Make arrangements with the involved deparmtents on the measurements planned
- Paperwok
- Training of staff
- Etc…
Kick Off meeting:
- Goal: to know tasks and responsibilities for every person involved.
- How: discuss every step in the way from recruitment of a patient until the last visit.
Function of the monitoring board:
- Check of the progress of the study
- Quality check in random test of recruited patients:
o Informed consent
o In- and exclusion of criteria
o Source data verification
o Protocol violations
o Check of serious adverse events
- Goal: guarding safety of patients and quality of research
Declaration of Helsinki:
- Good Clinical Practice (GCP)
- Goals GCP and Declaration of Helsinki:
o Protection of humans (ethical principles, protection of personal information, safety
procedures, etc.)
o Standard for quality of research
Why do we have all these rules, laws, directives? Why do we need monitoring?
- Unethical medical experiments in minorities
- Fraude – falsification
