Part2: lifestyle medicine & CVD risk reduction

• Why is lifestyle modification so important:

  • reduces the need for pharmacological intervention
  • reduces the need for combination therapy
  • beneficial in terms if reducing overall cardiovascular risk
• Effects of Dietary Fatty Acids on Lipoproteins:

  • increase in saturated fatty acids:
  • increase in LDL
  • increase in HDL
  • TC:HDL is stable/unchanged
  • industrial produced trans fatty acids
  • increase in LDL
  • decrease in HDL
  • TC:HDL is severely increased
  • monounsaturated fatty acids
  • decrease in LDL
  • increase in HDL
  • TC:HDL is decreased
  • polyunsaturated fatty acids
  • decrease in LDL
  • increase in HDL
  • TC:HDL is severely decreased
• (IP) Trans Fatty Acids

  • derived from the production of partially hydrogenated MUFA/PUFA
  • intermediated melting point between solid (ie saturated fat) and oil at room temperature
  • food manufacturing industry (baking and frying)
  • attractive alternative to saturated fat as:
  • less costly
  • taste enhancing
  • extend product shelf life
• IPTFA and CHD

  • first found to be associated with an increase CHD risk in the landmark Nurses Health study in the early 1990S
  • a subsequent meta-analysis of four prospective cohort studies (including the NHS) involving nearly 140,000 subjects confirmed this finding
  • in developed countries, the average intake of TFA stands at about 2 to 4% of total energy intake
  • a 2% increase in energy intake from IPTFA was associated with a 23% increase in the incidence of CHD
• key point:

  • dietary fatty acid stratergy:
  • diet low in saturated fatty acids: less than 10% in total caloric intake (replace with polyunsaturated fatty acids > monounsaturated fatty acids) (both are good but PUFA are better)
  • avoid IPTFA
  • leads to decrease in LDLs by 10 to 15%
• Fat substitution:

  • bad fats
  • saturated
  • increase in total and LDL cholesterol
  • trans fats
  • behaves like saturated fat
  • good fats
  • monosaturated
  • decrease in triglycerides
  • increase in good cholesterol
  • polyunsaturated
  • helps decrease total and LDL cholesterol
• • adding other LDL lowering lifestyle modifications
  • such as increase in calorie expenditure and decrease in calorie intake
  • can decrease LDL by 20 to 25%
• Other dietary related:

  • dietary fibre: 20 to 25 grams per day -> decrease in LDL by around 5 to 10%
  • dietary cholesterol: little evidence to support a major association between dietary cholesterol and coronary heart disease risk in the general population with the caveat that it may have a detrimental effect in hyperresponders (Djousse, 2009)
• Physical activity & dyslipidaemia:

  • for LDL lowering as a part of weight loss:
  • 250 to 300 minutes of moderate intensity aerobic activity over the week
  • ideally 3 to 4 times resistance exercise per week
• Weight loss:

  • for every 10 kg loss in weight, you see
  • ~ 5 to 10% decrease in total cholesterol
  • significant decrease in LDL
  • HDL cholesterol increase in stable state (~ 0.007 mmol/l HDL increase for every 1 kg lost)
  • significant decrease in triglycerides
• Lipoprotein change with exercise:

  • the change in lipoproteins is more to do with HDL's and triglycerides
  • exercise causes an increase in HDL's, the more intense the exercise, the bigger the increase in HDL's

  
• Lipoprotein change with exercise:

  • the change in lipoproteins is more to do with HDL's and triglycerides
  • exercise causes a decrease in triglycerides
  • even low dose moderate intensity causes a large decrease in triglycerides

  
• Lipoprotein change with exercise:

  • regular aerobic exercise causes increase in HDL by 3 to 10% (up to 0,16 mmol/L) - most consistent response is increase in HDL by ~5%, vigorous achieves more than less intense exercise
  • decrease in triglycerides by about 11% (up to 0.34 mmol/L)
  • decrease in LDL are less consistent by may promote formation of "healthier" LDL particles
  • exercise training also appears to decrease the effect of the decrease in HDL accompanying a decrease in dietary intake of saturated fatty acids
• • if you're a cardiovascular patient (e.g. diabetes, smoking, hyperlipidaemia, hypertension etc):
  • if youre physically fit / high cardiorespiratory fitness (such as 8 METs) your risk of premature mortality is lower than someone who's not fit (5 METs)

  
• Sedentary time is important too:

  • every 2 hours of sitting time / day replace with standing time:
  • 11% lower triglycerides levels
  • 6% decrease in total/HDL cholesterol ratio
  • 0.06 mmol/L increase in HDL
  • replacing sitting time with stepping had even more significant benefit
  • screen time:
  • more than or equal to 4 hours of screen time significantly causes decrease in HDL levels
  • those in the highest screen time category also had a significant increase in triglyceride levels
• • in cardiac rehabilitation graduates, who all had the same exercise training, those who were more sedentary the rest of their normal day, had lower fitness and poorer CVD risk profile
• Smoking:

  • causes decrease in HDL
  • smoking cessation causes increase in HDL by 0.1 mmol/L (4 mg/dl)
• Change in Lipid Profile with lifestyle modification:

  • Weight loss:
  • decrease in LDL
  • increase in HDL
  • decrease in triglycerides
  • Physical Activity:
  • no change in LDL
  • increase in HDL
  • decrease in triglycerides
  • Stopping Smoking:
  • no change in LDL
  • increase in HDL
  • no change in triglycerides
  • Reduce Alcohol:
  • no change in LDL
  • decrease in HDL
  • decrease in triglycerides
  • decrease in saturated fatty acids + substituted with polyunsaturated fatty acids:
  • decrease in LDL
  • increase in HDL
  • no change in triglycerides
• Effect of Alcohol Reduction on Blood Pressure:

  • meta-analysis of 14 studies - note heavy alcohol consumption is considered to be more than or equal to 3 drinks per day
  • random allocation of alcohol reduction and control
  • alcohol reduction was only intervention
  • intervention at more than or equal to 1 week
  • measuring change in systolic blood pressure and/or diastolic blood pressure
  • results:
  • average net change in systolic blood pressure was a decrease of 3.1 mmHg
  • average net change in diastolic blood pressure was a decrease of 2.04 mmHg
• Alcohol - Summary:

  • strong evidence linking alcohol with blood pressure with a dose response effect
  • consistent increase and decrease in blood pressure with administration and cessation of alcohol (subacute pressor effect)
  • therapeutic benefit (days to weeks) of alcohol restriction
  • decrease in alcohol consumption causes decrease in blood pressure in normotensive/hypertensive (~ 3/2 mmHg)
  • probably no safe limit, but at least less than 2 drinks per day
• • a decrease in salt intake is correlated to:
  • a decrease in blood pressure
  • a decrease in risk of stroke
  • a decrease in risk of coronary heart disease

  
• Salt:

  • the average UK salt consumption is ~ 9 grams per day
  • dietary requirement is ~ 1.4 grams per day
  • ~ 70 to 80% of salt consumed is intrinsic in our food
  • food groups contributing the most salt to our diet:
  • 35% from cereal & cereal products e.g. bread, breakfast cereals, "morning goods"
  • 26% from meat & meat products e.g. bacon & ham, burgers, sausages
  • 8% from milk & milk products e.g. milk, cheese
• • less than 0.25 g of salt per 100 g of food is low
  • 0.25 to 1.25 g of salt per 100 g of food is moderate
  • more than 1.25 g of salt per 100 g of food is salted
  • low salt foods:
  • fresh fruit, vegetables
  • pulses, lentils
  • unsalted nuts
  • rice
  • pasta
  • egg noodles
  • chicken
  • egg
  • high salt foods:
  • canned produce
  • processed meats
  • ready meals
  • packet food
  • bread
  • some cereals
  • cheese
  • bottle sauce ie ketchup, soy
  • bacon/sausage/beef burgers
  • pates/smoked or tinned fish
• Obesity and Hypertension:

  • obesity -> increase in fatty acids, increase in leptin, decrease in CNPS, increase in OSA -> increase in RAAS, increase in SNS -> vasoconstriction, sodium retention, increase in cardiac output -> hypertension
• Weight and blood pressure:

  • the relationship between weight loss and decrease in blood pressure appears to be linear
  • by and large, a decrease of 1 kg body weight is associated with 2/1 mmHg decrease in blood pressure
  • decrease in blood pressure due to weight loss is relation to the decrease in visceral fat
• DASH diet:

  • ~ 450 adults with a blood pressure less than 160 systolic and between 80 to 95 diastolic
  • 3 groups, 8 week diet
  • typical US diet
  • fruit and veg
  • fruits, veg, low fat dairy foods and reduced amounts of saturated fat, total fat and cholesterol
  • sodium concentration was the same in each diet
  • went onto do the DASH sodium diet:
  • 412 adults with blood pressure more than 120/80 and less than 159/95
  • the typical US diet was a control diet
  • DASH diet
  • also 3 different sodium levels
  • high (150 mmol/d)
  • intermediate (100 mmol/d)
  • low (50 mmol/day)
  • result:
  • DASH diet with low sodium
  • 11.5 mmHg decrease in systolic blood pressure in hypertensives
  • 7.1 mmHg in non-hypertensives
• Physical Activity:

  • meta-analysis of random controlled trails of aerobic exercise reduced blood pressure by 5/3 mmHg
  • independent of weight reduction
  • blood pressure decreased similarly in normal vs hypertensive
  • dose-dependent to a point (up to 90 mins/week)
• Changes in blood pressure with lifestyle modification:

  • weight reduction causes a 1 mmHg decrease in systolic blood pressure per kilogram
  • DASH eating plan causes a 8 to 14 mmHg decrease in systolic blood pressure
  • Decrease in sodium intake causes a 2 to 8 mmHg decrease in systolic blood pressure
  • Moderating alcohol intake causes a 4 to 7 mmHg decrease in systolic blood pressure
  • Physical activity causes a 2 to 3 mmHg decrease in systolic blood pressure
• Finnish Diabetes Prevention Study

  • 522 overweight and obese patients with impaired fasting glucose randomised to intervention or usual care for 3 years
  • found that lifestyle modification reduces the risk of developing diabetes mellitus
• Diabetes Prevention Program (DPP)

  • 3,234 patients with elevated fasting and post load glucose levels randomised to placebo, metformin (850 mg bid) or lifestyle modification for 3 years
  • shows that lifestyle modification reduces the risk of developing diabetes mellitus
• • 458 Japanese men with impaired glucose tolerance randomised to standard lifestyle intervention (goal BMI of less than 24 kg/m^2) or intensive lifestyle intervention (goal BMI of less than 22 kg/m^2)
  • shows that more intensive lifestyle modification causes a decrease in risk of diabetes mellitus
• • meta-analysis of 8 clinical trials evaluating the impact of diet and exercise on the risk of diabetes mellitus among at risk individuals
  • lifestyle interventions among at risk individuals reduce the risk of diabetes mellitus
• • mechanisms by which diabetes mellitus leads to coronary heart disease
  • infection
  • decrease in defence mechanisms
  • increase in pathogen burden
  • inflammation
  • increase in IL6
  • increase in CRP
  • increase in SAA
  • hyperglycaemia
  • increase in AGE
  • increase in oxidative stress
  • insulin resistance
  • hypertension
  • endothelial dysfunction
  • dyslipidaemia
  • increase in LDL
  • increase in triglycerides
  • decrease in HDL
  • thrombosis
  • increase in PAI1
  • increase in TF
  • decrease in tPA
  • all of the above lead to subclinical atherosclerosis -> atherosclerotic clinical events
• Diabetes Mellitus - Effect of exercise:

  • insulin resistance atherosclerosis study (IRAS)
  • prospective observational study of 1467 patients with glucose tolerance ranging between normal and mild non-insulin-dependent diabetes mellitus
  • results shows that regular exercise improves insulin sensitivity and lowers fasting insulin levels
• Diabetes Mellitus - Effect of exercise:

  • 251 diabetic patients randomised to aerobic training, resistance training, or a combination of both types for 22 weeks
  • results showed that while either aerobic or resistance training improves glycaemic control in diabetes mellitus, greater improvement occurs with a combination of the two
• Diabetes Mellitus - Effect of intensive risk factor modification:

  • 160 patients with type 2 diabetes mellitus randomised to targeted intensive multifactorial intervention or conventional treatment of cardiovascular treatment of cardiovascular risk factors for 8 years
  • results showed that intensive risk factor modification reduced cardiovascular events in diabetes mellitus
• Diabetes Mellitus - Effect of intensive risk factor modification:

  • look AHEAD (action for health in diabetes) study
  • 5145 patients with type 2 diabetes mellitus randomised to an intensive lifestyle intervention (ILI) or conventional diabetes support and education (DSE) for 1 year
  • results showed that intensive lifestyle intervention in type 2 diabetics improves weight loss, glycaemic control and control of cardiovascular risk factors
• • sugars:
  • low = 5 grams or less per 100 grams of food
  • medium = 5.1 grams to 15 grams per 100 grams of food
  • high = more than 15 grams per 100 grams of food
  • fat:
  • low = 3 grams or less per 100 grams of food
  • medium = 3.1 grams to 20 grams per 100 grams of food
  • high = more than 20 grams per 100 grams of food
  • saturates:
  • low = 1.5 grams or less per 100 grams of food
  • medium = 1.6 grams to 5 grams per 100 grams of food
  • high = more than 5 grams per 100 grams of food
  • salt:
  • low = 0.3 grams or less per 100 grams of food
  • medium = 0.31 grams to 1.5 grams per 100 grams of food
  • high = more than 1.5 grams per 100 grams of food
  • high fibre = 6 grams or more per 100 grams
• Overall key lifestyle messages:

  • eating primarily plant based foods
  • replacing butter with health fats such as olive oil and canola/rapeseed oil
  • limiting processed foods and avoiding trans fats
  • using herbs and spices instead of salt to flavour foods (less than 5 grams per day)
  • replacing red meat with fish and poultry
  • eating fish at least twice a week
  • drinking alcohol in moderation (11 units for women, 17 units for men)
  • getting plenty of exercise
  • reduce sitting time
  • tobacco cessation