Nutritional Assessment 3 PDF

Nutritional Assessment Part 3 NUTR 344 – WINTER 2024 Biochemical Assessment Biochemical Assessment Measurement of nutritional markers in blood, urine and other fluids and tissues Detects subclinical nutrient deficiencies Examine:  Visceral and somatic proteins  Hematological assessment  L...

Nutritional Assessment Part 3 NUTR 344 – WINTER 2024 Biochemical Assessment Biochemical Assessment Measurement of nutritional markers in blood, urine and other fluids and tissues Detects subclinical nutrient deficiencies Examine:  Visceral and somatic proteins  Hematological assessment  Lipid profile  Micronutrient assessment  Immunocompetence assessment Affected by: nutritional status, If hb is low: can be for a lot of reason, medication, illness/physiological state need to make assessment of the whole health to know it Clinical Laboratory Values and SI Units SI: “le système international d’unités” Uniform system of reporting lab values Facilitates interchanging information between disciplines SI Units– Base units Base unit SI symbol meter m Mass gram - kilogram g - kg Time second s Amount of substance mole mol Thermodynamic temperature Kelvin K Electric current ampere A Luminous intensity candela cd Length SI unit style specifications Wrong Right Use lowercase Kg Kcal kg kcal or Cal Symbols are not followed by period m. m Do not pluralize kgs kg 100 meters 100 m 60kg 60 kg Add a zero before decimal .01 0.01 Decimals are preferred to fractions 3/4 0.75 1,000,000 1 000 000 Symbols preferred Leave a space between value and unit Use spaces to separate long numbers Some useful conversions Serum concentration Old way Conversion factor SI unit Albumin 3.5-5.0 g/dL 10 35-50 g/L Glucose 70-110 mg/dL 0.05551 3.9-6.1 mmol/L Iron 60-180 µg/dL 0.1791 11-32 µmol/L need to know these 2 1. Protein Status Assessment Visceral protein status is reflected by serum proteins, red blood cells (RBC), white blood cells (WBC) malnutrition Body will start losing protein if malnutrition over long term, if during one day, will be supply by other storages (fat, CHO) ↓ organ mass and substrate supply most synthesized in liver less protein turnover bc don’t have material required ↓ synthesis of serum proteins 1.1 Serum proteins need to know proportionally which ones are the most abundant and less one (but not the specific numbers) Serum proteins can give you information abt nutritional status, but not specific to it by influenced by a lot of stuff Low sensitivity and specificity for nutritional status, influenced by: Low protein intake Altered metabolism and synthesis Inflammation Hydration Medications Pregnancy Exercise bc blood volume goes up Serum proteins – half life Albumin (most abundant): T ½ 17-21 days Transferrin: T ½ 8-10 days Prealbumin or transthyretin (TTR): T ½ 2-3 days Retinol Binding Protein (RBP): T ½ 10-12 hours  See Table 3.11 in Nelms don’t need to know the table how long does it take for the protein to become half shorter half life: more rapid turnover of that protein —> better marker of a particular change that is taking place Ex: Albumin: takes 3 weeks to see a change in albumin levels —> not a good biomarker to see effect of a tx Need to know the half life of these proteins Serum proteins - Interpretation Function High during… Low during… Albumin Maintains osmotic pressure Transport of large insoluble molecules, drugs, Ca, Zn Dehydration, corticosteroids Low protein intake, malabsorption, inflammation, nephrotic syndrome, trauma, surgery, edema, cirrhosis, overhydration, acute illness, aging Transferrin Iron transport Fe deficiency, pregnancy Inflammation, infection, acute illness, PEM Transthyretin (TTR) Transport of T3 and T4 thyroid Renal failure, hormone Complex with RBP Hodgkins disease Retinol-binding Protein (RBP) vit A Retinol transport from liver to periphery Complex with TTR Renal failure bc less synthesis of it Liver diseases, PEM, inflammation, hyperthyroidism Vitamin A deficiency, zinc deficiency, liver diseases, inflammation, hyperthyroidism Acute-Phase Serum Proteins Albumin, transferrin, TTR and RBP are negative acute-phase proteins: levels decrease by >25% during inflammation, illness or metabolic stress C-reactive protein (CRP) is a positive acute-phase protein ◦ Used to detect mild or acute inflammation ◦ Normal <1, mild chronic 1-5, acute >5 mg/L ◦ Not a nutritional marker but very useful to interpret other serum proteins if high, knows that it’s probably bc inflammation Cutoffs for serum protein deficits only need to memorize normal values Mild deficit Moderate deficit Severe deficit Albumin (g/L) 30-35 24-29.9 <24 Transferrin (g/L) 1.5-2.0 1.0-1.5 <1.0 0.10-0.15 0.05-0.10 <0.05 TTR (g/L) 1.2 Somatic Protein Status Nitrogen balance: reflects total protein retention or losses (but not mass) balance of protein when you compare intake of nitrogen/prot and loss of nitrogen/prot BUT NOT MASS Urinary creatinine excretion: reflects skeletal muscle mass Tell status right now, but not abt in and out Immunocompetence: Total Lymphocyte Count (TLC)  influenced by infection, trauma, diseases, medications, … Nitrogen Balance Balance (anabolism=catabolism): normal, healthy adult Positive (anabolism>catabolism) ◦ Pregnancy, growth, recovery from illness, athletic training Negative (anabolism<catabolism) ◦ Starvation, trauma, surgery, inadequate protein intake, poor quality protein intake Nitrogen Balance N Balance = intake - excretion N Balance (g/day) = (pro intake g/6.25) - (UUN g + 4) 1 g nitrogen = 6.25 g protein (N comprises 16% of proteins) Total 24-h Urinary Urea N (mmol) = (UUN mmol/L)(24h-urine volume L)  Conversion factor: 1 mmol UUN = 0.028 g UUN Factor 4 is g of protein losses from N excretion via skin and feces Nitrogen Balance - Application N Balance (g/day) = (pro intake g/ 6.25) - (UUN g + 4) Patient intake of 62.5 g protein/day and excretion of 200 mmol/L UUN, in 2.0 L of urine UUN (g) = (200 mmol/L x 0.028 g/L) x 2 L = 11.2 g N balance = 62.5/6.25 - (11.2 + 4) = - 5.2 g  negative balance: current intake is insufficient to maintain N balance If +: not harmful in itself, maybe it’s a good thing —> not necessarily a bad thing -1 and +2: don’t need to worry abt it If lower than -1: need to worry abt it Nitrogen Balance: Limitations Time consuming: 24 h (ideally 3 x 24h) Prone to errors:  Protein intake: estimated vs. measured  Missed or incomplete urine collections  Does not account for losses due to diarrhea, vomiting, wound leaks,… Errors always favor a more positive balance (overestimation of intake + underestimation of losses) Urinary Creatinine Excretion Excretion is proportional to skeletal muscle mass bc meat is muscle  with exercise, meat intake, menstruation, infection, fever, trauma  with renal failure and age the taller someone is, the more muscle mass they are going to have Normal excretion (Table 3.10, Nelms): If someone has less lean body mass, creatinine excretion will be less bc less muscle Women: 18 mg/kg IBW: e.g. 50.9 kg female excretes 916 mg/24 h Men: 23 mg/kg IBW: e.g. 77 kg male excretes 1771 mg/24 h don’t have to know these Creatinine Height Index Creatinine Height Index CHI = observed 24h creatinine excreted (mg)/ expected 24h creatinine excretion (mg) (table 3.10 in Nelms) Interpretation :  60-80% mild depletion  40-59% moderate  <40% severe Limitations:  Rely on complete 24h urine collections: errors if you eat a lot of meat, will look like you have a - nitrogen balance but not necessarily the  Meat-free diet prior to testing case bc maybe you are just excreting the extra nitrogen that you don’t need from the meat Mini-Application #2 Some available laboratory results of Mr. G.: Serum concentrations: Albumin 37 g/L Transferrin 3.0 g/L weight loss diarrhea might be anemic might be dehydrated: less plasma volume, that’s why albumin may look higher than it actually is need to rehydrate Mr. G and test the albumin again need to look at electrolytes level Prealbumin 0.14 g/L Do these data correspond to a protein deficiency diagnosis? What other possibilities could explain these findings? 2. Hematological Assessment Complete blood count (CBC): erythrocytes (number, size, shape, color) to diagnose anemia(s) Anemia:  Reduction in the quantity of hemoglobin or in the number of RBC in the blood  Leads to a decreased oxygen carrying capacity Classification: - Color • Hypochromic (pale color) • Normochromic • Hyperchromic (darker color) - Size • Microcytic (small cells) • Normocytic • Macrocytic (large cells) Anemias May be due to deficiencies of: - Iron (microcytic, hypochromic) - Folate (macrocytic, megaloblastic) - Vitamin B12 (macrocytic, megaloblastic) - Other micronutrients (Vitamin C, E) - Anemia of chronic diseases (normocytic, normochromic)  See Chapter 19 for more reading and review Laboratory Tests for Anemia: General • Hemoglobin (g/L, deficit <120 women; <140 men) - Total amount in RBC -  during PEM, hemorrhage and other anemias • Hematocrit (%, deficit <37 women; <40 men) - % of RBC in total blood volume -  during dehydration -  during hemorrhage and water overload • RBC count (x1012/L, deficit <4.2 women; <4.5 men) Laboratory Tests for Anemia: General • Mean Corpuscular Volume (MCV) - RBC size: microcytic (<76) vs. macrocytic (>100 µm3) - MCV = [Hct / RBC] X 10 • Mean Corpuscular Hemoglobin (MCH) - Hb concentration in RBC (in pg/cell): hypochromic (<21) vs. hyperchromic (>38) • MCHC = Hb/Hct Iron Status Assessment • Storage Iron - Liver, bone marrow, spleen - Ferritin • Transport Iron - Transferrin saturation • Essential Iron – RBC, myoglobin, enzymes Order of depletion during iron deficiency Lab Tests for Anemia: Iron Deficiency • Serum Ferritin (deficit <20 µg/L) - Low in early deficiency state - Reflects depletion of iron stores • Serum Iron (deficit <0.65 mg/L) - Low in early deficiency state - Reflects iron bound to transferrin • Total Iron Binding Capacity, TIBC (deficit >4.5 mg/L; N=2.4-4.5 mg/L) - Measures the saturation ability for transferrin, high in deficiency - Needed to calculate transferrin saturation Lab Tests for Anemia: Iron Deficiency • Transferrin Saturation (deficit <30%) - Progressively decreases with diminished transport iron - [S. iron / TIBC] X 100% • Erythrocyte Protoporphyrin (>3 mg/L) - Increases in later deficiency state with limited Hb production Lab Tests for Anemia: Folate Deficiency • Serum Folate (N= 4.5-45 nmol/L) - Low in progressing deficiency state • RBC Folate - Low in later deficiency state • Folate deficiency: low serum and RBC folate + megaloblastic, macrocytic RBC (+ normal B12) Lab Tests for Anemia: Vitamin B12 Deficiency • Serum B12 (N=120-500 pmol/L) - Low in progressing deficiency state Megaloblastic, macrocytic RBC + serum total cobalamin have normal folate level and this biomarker is Biomarker: ↑ methylmalonic acid (early) ifhigh and low cobalamin —> probably B12 - Biomarker of B12 and folate deficiency: ↑homocysteine deficiency —> takes a lot of time to have deficiency bc have a big store in liver Increasing depletion of body iron Iron Stores RBC Iron Serum Ferritin Normal Fe depletion Fe deficiency anemia Increasing depletion of body iron Transferrin Saturation Free Erythrocyte Protoporphyrin Hemoglobin concentration Normal Fe depletion Fe deficiency anemia Iron requirements: DRIs • Men (>19 y): 8 mg/day • Pre-menopausal women: 18 mg/day • Post menopausal (>50 y): 8 mg/day • Pregnancy (19-50 y): 27 mg/day • Lactation (19-50 y): 9 mg/day infant relies on iron stores from birth Food Sources of Iron: Heme iron Excellent Sources (>3.5 mg) Good Sources (>2.1 mg) Sources (0.7 mg) Clams, oysters, liver Beef cooked, blood pudding, turkey (dark meat ) Chicken, ham, lamb, pork, veal, halibut, haddock, perch, salmon, shrimp Food Sources of Iron: Non-heme iron Excellent Sources (>3.5 mg) Cooked legumes, seeds, fortified cereals, tofu Good Sources (>2.1 mg) Sources (>0.7 mg) Canned legumes, enriched egg noodles, dried apricots Nuts, sunflower seeds, cooked pasta, bread, bran muffin, cooked oatmeal, wheat germ Risk Factors for Poor Iron Status • Diet low in meat, fish, poultry • Diet low in vitamin C • Diet low in fortified foods (infants) • Frequent consumption of tea and coffee w/meals (tannins and polyphenols) • Frequent consumption of iron inhibitors w/meals (phytates, oxalates) • Regular ASA use (aspirin) bc acute blood loss • Menorrhagia (excessive menstrual losses) • 3 or more annual blood donations • Pregnancy, multiple gestations, parity >3 Iron Supplementation • Ferrous sulfate (200 mg TID X 6 months) not heme iron • 3 X better absorption with ferrous than other forms • Liquid or tablet form • Expect a rise in hemoglobin of 1 g/L per week • To maximize absorption - Take on an empty stomach with liquid • Food decreases absorption by 1/3 - BUT careful of side effects (take before/with snack) Routine admission lab measurements Other lab tests often due when someone is admitted in hospital Vitamin and mineral assessment Most common: - Vitamin D: serum 25(OH)D Folate Vitamin B12 Thiamine (alcoholism) liver function kenny function See Appendix E for ranges and description liver function when cell dies, release of LDH Mini-Application #3 Given the following data assess Mr. G.’s hematological status: - Hb: 145 g/L (N=140-180 g/L) - ferritin: 9.3 μg/L (N= 30 μg/L) really low - folate: 5.3 nmol/L (N=4.5 45 nmol/L) - B12: 280 pmol/L (N=120-500 pmol/L) - MCV: 80 um3 (N=76-100) - MCHC: 0.32 (N=0.32-0.36) bordeline - Transferrin saturation: 27% (N= >30%) a bit low on the low side – RBC: 4.8 x 1012/L (N=4.6-6.2 x 1012/L) okay, but depleted iron store —> first step of iron deficiency  What, if anything, would you recommend to Mr. G? bc Hb good prescribe diet with iron rich foods, don’t prescribe supplements yet Clinical Assessment  Nelms Table 3.13 and Appendices F and G Includes patient’s medical, social, and psychological history Physical examination for clinical signs and symptoms of nutritional deficiencies through visual inspection and palpation Patient History diarrhea • Primary and secondary diagnosis primary: doing test to know the diagnosis • Past medical history • Weight history • Factors affecting nutrient intake (body systems) • Social history (religion, socioeconomic, shopping, cooking, family) of food don’t need to know these signs want to catch it bc malnutrition signs bc it means that they already have a big deficiency Physical Signs of Malnutrition Malnutrition Possible deficiency in: Hair: shiny, not easily pluckable, normal Dry, dull, alopecia, brittle, early graying Protein, energy, zinc, copper, EFA Face: uniform, not swollen Fullness, puffy, Protein, energy Eyes: bright, clear, shiny, moist membranes Dryness, pallor, corneal vascularization Normal cheeks drawn in Vit A, iron, B vitamins Physical Signs of Malnutrition Normal Malnutrition Possible deficiency in: Lips: pink, moist, smooth Angular stomatitis, cheilosis Niacin, riboflavin, iron, B6 Tongue: pink, moist, smooth, taste buds Magenta, painful, edema, smooth, taste changes, glossitis B vitamins, zinc, vit A, iron Gums and teeth Bleeding receding gums, gingivitis, gums are pink, stomatitis, caries teeth white and shiny Vit C, folate, B12, protein, energy, fluoride Physical Signs of Malnutrition Normal Malnutrition Possible deficiency in: Skin: smooth, no rashes or swelling Dryness, scaliness, delayed wound healing, Vit A, zinc, EFA, protein, vit C, biotin Nails: pink, firm Spoon nails, egg shell nails Iron, chromium, vit A Musculoskeletal: good tone, normal movement Wasting, weakness, Bone pain Protein, energy, thiamin, calcium, vit D Physical Signs of Malnutrition Normal Malnutrition Possible deficiency in: Neurological: Psychologically stable, normal reflexes Sensory loss, confusion Depressed reflexes, dementia, tetany thiamin, B6 niacin, B12, protein Abdomen: symmetrical, flat Distention, flatus Protein, energy, lactose intolerance calcium, magnesium Environmental assessment Similar to patient’s social history: Socio-economic status, food security/access to food Education, food and nutrition literacy Ability/time to cook Working schedule, traveling Allergies, intolerances, restrictions Cognitive function … Functional Assessment – Handgrip strength  Muscle strength correlates with muscle mass  Predicts malnutrition in many patient populations  Handgrip strength measured with a dynamometer  Repeated 3 times on dominant hand take the average of the 3 times  Should be ≥23 kg women, ≥35 kg men  ≥ 20.4 kg women, ≥ 33.1 kg men over 65 years (Tessier AJ et al. J Cachexia Sarc Muscle 2019) Functional assessment – other tests Gait speed Chair stand speed to walk a little distance easiness to get up and down from a chair Activities of daily living (ADL) (Table 3.14) able to go to the bathroom, cook, etc. more components than activities of daily living Instrumental activities of daily living (IADL) can you take care of children, other ppl, etc. Self-reported perception of activities will tell you I have difficulty doing this or that