Hypertension Part 1 Flashcards
1
Q
What are the major forms of CVD?
A
- HTN
- Atherosclerosis
- Ischemic Heart
- Peripheral Vascular Disease
- Heart Failure
2
Q
What are the trends in prevalence of reported HTN?
A
- 28%
- increasing for both from 2011
- pretty much the same for men and women and seems to go up for men
3
Q
What is the reported prevalence in 2014 of HTN?
A
there are more women than men
4
Q
What is the percentage of ppl who are unaware of HTN?
A
18%
5
Q
What is the percentage of ppl who are aware and not treated of HTN?
A
4%
6
Q
What is the percentage of ppl who are treated by medication and not controlled of HTN?
A
65%
7
Q
What is the percentage of ppl who are treated by medication and not controlled of HTN?
A
14%
8
Q
The lifetime risk for developing HTN among adults age 55-65 years with normal blood pressure is ___
A
90%
9
Q
What is the epidemiology of HTN?
A
- 1 in 3 adults Americans have
10
Q
Which ethnicity is more prone to have HTN?
A
African Americans
11
Q
What is blood pressure?
A
cardiac output x peripheral resistance
12
Q
What is cardiac output?
A
2 phases:
- contraction (systolic)
- resting (diastolic)
stroke volume x heart rate
13
Q
What is resistance?
A
(length of vessel x viscosity of the blood)/radiusˆ4
** even a small change in radium will greatly affect the resistance and thus the blood pressure
14
Q
How is mean arterial blood pressure determined?
A
determines by cardiac output and total peripheral resistance
15
Q
What are the 4 factors that regulate bp?
A
- sympathetic nervous system
- RAAS
- Renal function
- Hormones involved: epinephrine, ADH, angiotensin II
16
Q
HTN can cause…
A
hemorrhage stroke Left ventricular hypertrophy CHD CHF Renal failure Proteinuria Peripheral vascular disease Retinopathy
17
Q
What is the device used to measure BP?
A
Sphyngomanometer
18
Q
What is systolic blood pressure?
A
max. pressure the heart exerts while beating
19
Q
What is diastolic BP?
A
amount of pressure in the arteries between beats
20
Q
What type of HTN is benign?
A
family history of higher BP than normal –> not harmful
21
Q
What type of HTN is malignant?
A
occurring for other reasons (disease, diet, lifestyle)
22
Q
What is the primary cause of HTN?
A
- unknown etiology
- influenced by dietary and behavioral factors
23
Q
What is the secondary cause of HTN?
A
- occurs secondary to a condition such as renal, endocrine or neurological disorders.
24
Q
What is the nickname of HTN?
A
silent killer
25
What is the etiology of HTN?
the exact etiology is not known but very likely of mixture of a lot of risk factors. Largely influenced bu diet, exercise, stress and smoking...
26
What is a normal BP level?
SBP --> 90-119
| DBP --> 60-79
27
What is considered pre-HTN?
SBP --> 120-139
| DBP --> 80-89
28
What is considered Stage I HTN?
SBP --> 140-159
| DBP --> 90-99
29
What is considered Stage II HTN?
SBP --> 160-179
| DBP --> 100-109
30
What is considered Stage III HTN?
SBP --> >180
| DBP --> >110
31
What are non-modifiable risk factors for HTN?
- age >60
- men, premenopausal women, ethnicity (African American, Russian, Finns)
- Family history of CVD: women <65, men <55
32
What are modifiable risk factors of HTN?
- smoking
- sendentary lifestyle
- abdominal obesity, insulin resistance
- excess sodium intake
- poor diet quality
- stress
33
How does excessive secretion of vasopressin and angiotensin II affect BP?
increases vasoconstriction and fluid retention
34
How does smoking affect BP?
interferes with NO (nitric oxide) --> impairs endothelial vasodilation
35
How does renal disease affect BP?
reduced blood flow causes more angiotensin II secretion which leads to vasoconstriction and Na, Cl, and water retention --> increased blood volume
36
How do adrenal disorders affect BP?
- Adrenal disorders that increase secretion fo epinephrine and norepinephrine --> vasoconstriction --> increased cardiac output
- hyperinsulinemia is associated: mechanisms unclear
37
What is the risk of HTN of a person that has no risk factors and SBP 140-159 and DBP 90-99?
low
38
What is the risk of HTN of a person that has 1-2 risk factors and SBP 140-159 and DBP 90-99?
medium
39
What is the risk of HTN of a person that has more than 3 risk factors and SBP 140-159 and DBP 90-99?
high
40
What is the risk of HTN of a person that has no risk factors and SBP 160-179 and DBP 100-109?
medium
41
What is the risk of HTN of a person that has 1-2 risk factors and SBP 160-179 and DBP 100-109?
medium
42
What is the risk of HTN of a person that has more than 3 risk factors and SBP 160-179 and DBP 100-109?
high
43
What is the risk of HTN of a person that has no risk factors and SBP >180 and DBP >110?
high
44
What is the risk of HTN of a person that has 1-2 risk factors and SBP >180 and DBP >110?
very high
45
What is the risk of HTN of a person that has more than 3 risk factors and SBP >180 and DBP >110?
very high
46
What are the 2 blood pressure measurement methods? Which one is preferred?
oscillometric (electronic) --> preferred
| auscultatory (mercury)
47
How to treat HTN?
- reduce risk of CD and renal disease
- lower BP to clinically appropriate level
- weight reduction
- physical activity
- nutrition therapy
- pharmacological interventions
48
What are the pharmacological interventions that can be used to treat HTN?
- loop diuretics
- thiazides
- carbonic anhydrase inhibitors
- potassium sparing diuretics
49
What are the causes of HTN associated with obesity?
- insulin resistance/hyperinsulinemia
- overactivity of sympathetic nervous system
- alterations in RAAS
- Leptin mediates sympathetic activity, this function is preserved with leptin resistance
50
How does weight loss affect HTN by numbers?
5-20mmHg reduction per 10kg weight loss
51
What are the weight recommendations for HTN?
- BMI <25kg/m2
| - waist circumference <102cm men, <88cm women
52
What are the weight loss approaches for HTN?
- diet education and instruction
- increase P.A.
- behaviour modification
** weight loss be more difficult if patient using B-blockers
53
What is the name of the study that has been done on sodium and HTN?
The INTERSALT Study (1982-85)
54
What is the effect of sodium intake on HTN by numbers?
For every increase of 100mmol/Na/d --> increase in 3-6/0-3 mmHg SBP/DBP
55
What is salt sensitivity?
Salt sensitivity is a measure of how your blood pressure responds to salt intake. People are either salt-sensitive or salt-resistant. Those who are sensitive to salt are more likely to have high blood pressure than those who are resistant to salt.
56
What are the factors involved in heterogenous responses to Na reduction?
- familial/genetic factors
- age
- severity of HTN
- degree of restriction
- RAAS (low renin) --> genetic defect
- Sympathetic response (high NE response)
- duration of trials
- largely influenced by K --> increased K intake = decreased Na sensitivity
57
What is the AI for Na
14-50 --> 1500 mg/d
51-70 --> 1300 mg/d
71 + --> 1200 mg/d
58
What is the UL for salt
2300 mg/d
59
What are the recommendations of the 2014 Canadian HTN Education Program (CHEP)?
To decrease BP, consider reducing Na intake towards 2,000mg (5g of salt, 87 mmol of Na)
60
How much sodium does 1/2 tsp of salt have?
1,150 mg
61
What is hidden sodium?
77% from processed foods --> manufacturing and restaurants
62
What is conscious sodium?
11% added at the table and in cooking
63
What should we look for on labels in terms of sodium content?
- buy unsalted and lower sodium foods whenever possible --> "sodium-free", "low-sodium", "reduced sodium", "no added salt"
- check the serving size and note the amount of sodium -> chose the foods with less than 120mg sodium per serving or have a %DV of 5% or less.
64
What are the 3 categories of sodium controlled diets? Explain each
3000mg Na
- Eliminate high Na processed foods and beverages (fast foods, salad dressings, smoked meats, koshers meats, canned foods)
- up to 0.25 tsp salt permitted during cooking or added at table
2000mg Na
- eliminate processed and prepated foods and beverages high in Na. Limit milk and milk products to 2 cups/d
- no salt in preparation of foods or added at the table
1000mg Na
- same as above. Omit canned, frozen, deli foods, cheeses, margarines
- limit regular bread to 2 servings/d
65
What is the relationship between K and BP?
- inverse relationship
| - decreased prevalence of HTN with higher K intake
66
What are the mechanisms that K decrease BP?
- Natriuresis
- suppressed renin
- attenuates vascular contraction --> vasodilation
- may reduce sympathetic activity and angiotensin
67
What is the DRI for K?
4700 mg/d
68
What is the effect of potassium intake on HTN by numbers?
+ 50mmol (2000mg) --> - 3.4/-1.9 mmHg BP
69
What should the dietary intake of K be in order to decrease the risk of stroke mortality?
>60mmol (2300mg)
70
What are the recommendations of K supplementations for treatment of HTN?
- for normotensive ppl obtaining 60 mmol of dietary K per day, K supplementation is not recommended as a means of preventing high BP
- K supp. above DV of 60 mmol/d is not recommended as a treatment for HTN
- K should come from the diet
- K supplements may be useful with diuretics - induced hypokalemia treatment
71
What is the relationship between sodium and potassium?
- we always excrete the excess
- the higher sodium intake in the diet the more K will be lost even in higher K concentrations in blood
- high sodium diet will favour high potassium excretion
72
What are the risk factors for hypokalemia?
- Pt. using R-A-A inhibitors
- Pt. receiving other drugs causing hyperkalemia
- Chronic kidney disease
- Baseline serum (K > 4.5 mmol/L)
- DO NOT ADVISE INCREASED INTAKE OR SUPPLEMENTS.
73
How is Calcium related to BP?
inversely related
74
What are the potential mechanisms of increased calcium intake on BP?
- increased Na excretion
- increased sensitivity to NO --> vasodilation
- decreased production of superoxide molecules and prostanoids (vasoconstrictors)
75
What are the recommendations for calcium?
- for normotensive ppl Ca supplementation above RDA is not recommended as a means of preventing high BP
- Ca supplementation above RDA is not recommended as a treatment for HTN
- Using CFG and consuming 2-3 servings of milk products daily is sufficient
76
How is Magnesium related to BP?
- inverse relationship between Mg and BP
- potential mechanisms relate to the role of Mg in vascular structure and functionL regulates vascular reactivity and contractility
77
What are the recommendations for magnesium?
- increased dietary intake to reach DRI (men 420mg/d, women 320mg/d)
- supplement above DRIs not recommended
78
How is alcohol related to BP?
- dose response relationship between alcohol intake over 2 drinks/d and increased BP
- alcohol has an immediate vasovagal effect (decreases BP) but followed by elevated BP in the next 10-15h
79
What are the potential mechanisms of alcohol intake on BP?
- stimulation of sympathetic NS
- stimulation of cortisol secretion
- increased Ca uptake by cell membranes
- moderate consumption does not raise BP and has a cardioprotective effect
80
What are the recommendations for alcohol?
- limit to 2 drinks/day
- beer 360ml
- wine 150ml
- spirits 45ml
