Metabolic Syndrome Evaluation and treatment strategies
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Transcript Metabolic Syndrome Evaluation and treatment strategies
John Hyer
University of Georgia College of Pharmacy
Doctor of Pharmacy Candidate, 2012
Preceptor: Ali R. Rahimi, MD, FACP, AGSF
Objectives
• Define metabolic syndrome (MetS)
• Examine the risk and prevalence associated with
Metabolic syndrome (MetS)
• Evaluate current treatment strategies for efficacy
• Our role in prevention
Epidemiology
Approximately 25% of the world’s population has
metabolic syndrome
Interestingly enough (but not surprisingly), more than half of
the adults in U.S. are overweight or obese
Same or greater primary risk factor as smoking for CVD
(cardiovascular disease)
Numbers will increase with aging population and
increasing rates of childhood obesity
Peaks in mid to late 60’s
Epidemiology
Most common in men and Hispanics
Increases with age
Native Americans have highest recorded prevalence of
MetS
60% or women aged 45-49
45% of men aged 45-49
Cardio-Metabolic Syndrome risk is based on global
risk of metabolic syndrome
Risk factors
Central adiposity (waist
circumference)
Better association with MetS
than BMI
Peripheral adiposity is a weaker
predictor of MetS
Obesity
Sedentary lifestyle
Type 2 diabetes mellitus (T2DM)
Est. that up to 75% of patients
with T2DM or impaired
glucose tolerance have MetS
Lipodystrophy
Genetic or HAART induced
Aging
Postmenopausal status
Smoking
Low household income
Antipsychotic medications
Clozapine
Olanzapine
Pathophysiology of MetS
Widely debated
Most accepted hypothesis is insulin resistance
Insulin resistance precluded by:
Postprandial hyperinsulinemia followed by
Fasting hyperinsulinemia and hyperglycemia
Diabetes
obesity
diabesity
Insulin resistance
Increases with increasing body fat
Excess adipose tissue releases
Nonesterified fatty acids (NEFA)
High level overloads muscle and liver with lipids
Cytokines –
Increase glucose and VLDL-C production by liver
Plasminogen activator inhibitor-1 (PAI-1)
High levels contribute to a prothrombotic state
Adiponectin
Plays a role as an anti-inflammatory and insulin sensitizing agent
Reduced
Interleukin (IL)-6 elevation
Stimulate insulin resistance and lypolysis of adipose tissue TG
C-reactive protein (CRP)
Signifies cytokine excess and a proinflammatory state
Insulin resistance
Free fatty acids - contributor
Released from enlarged adipose tissue mass
Insulin responsible for
Antilipolysis
Most sensitive pathway of insulin action
Stimulation of hormone sensitive lipoprotein lipase
Mobilizes fatty acids from triglyceride rich stores
Insulin resistance = increased lipolysis produces more
FFA= further decreases antipolytic effect of insulin
Insulin resistance -FFAs
In muscle
High NEFA levels in muscle are diverted to the liver
Promoting fatty liver and atherogenic dyslipidemia
In the liver increases production of
Glucose
Triglycerides
Secretion of very-low-density lipoproteins
Insulin resistance
In muscle
FFA’s reduce insulin sensitivity by inhibiting insulinmediated glucose uptake
Leads to increased circulating glucose
Increases pancreatic insulin secretion – hyperinsulinemia
Results in enhanced sodium reabsorption and increased
sympathetic nervous system activity
Hypertension?
Take home Point!!!
Insulin resistance leads to oxidative stress which leads to
endothelial cell dysfunction, promoting vascular damage and
atheroma formation
Diagnosing Metabolic Syndrome
Metabolic Syndrome Defined
According to the National Cholesterol Education Program Adult
Treatment Panel III (NCEP ATP III) presence 0f 3 of the
following:
ATP III Criteria
Abdominal Obesity
Waist circumference > 40 inches
in men and 35 inches in female
Fasting plasma glucose (FPG)
FPG ≥ 100 mg/dL or drug
treatment for elevated blood
glucose
Blood pressure (BP)
BP > 130/85 mmHg or drug
treatment for blood pressure
Serum high-density lipoprotein
cholesterol (HDL-C)
HDL-C < 40 mg/dL in men and
< 50 mg/dL in women
Serum triglycerides
≥ 150 mg/dL or drug treatment
for elevated triglycerides
Evaluation
The American Heart Association
Recommends measurement of high-sensitivity CRP for risk
stratification in patients at high risk of CVD
Is patient ready to make therapeutic lifestyle
modifications? (i.e. reduce dietary fat)
Fasting glucose
Fasting lipid panel
Waist circumference
Height and weight (BMI)
Frammingham Risk Assessment for 10 Year CVD risk
Coronary Artery Calcium (CAC) scan (AHA/ACC)
Good in asymptomatic low-risk patients
Clinical Consequences
MetS
CVD and T2DM
Cardiovascular Disease (CVD)
High risk for developing CVD
MetS and the Framingham Risk Score
Which is better at predicting CVD?
Evidence for both camps in the literature
Relative risk for CVD events or death is 1.78 in patients
with MetS
Clinical Consequences
Type II Diabetes Mellitus
(T2DM)
Presence of MetS is
highly predictive of
developing new-onset
T2DM
75-85% of patients with
MetS will progress to
T2DM
Relative risk of 3.53-5.17 for
development of diabetes
T2DM
Insulin
resistance
Hyperinsulinemia
Dyslipidemia
Obesity
Therapy
Difficult
No randomized controlled trials for specific treatment
options
Goal
Reduce the risk for or preventing CVD and T2DM
NCEP ATP III Major Therapeutic Goals in Patients with
MetS
1. Treat underlying causes (overweight/obesity and
physical inactivity) by intensifying weight management
and increasing physical activity
2. Treating cardiovascular risk factors if they persist
despite lifestyle modification
*** lifestyle modifications, pharmacologic therapy, and
bariatric surgery***
Lifestyle Modifications
Lifestyle Modifications
Diet
Even a modest weight loss significantly reduced prevalence of
MetS
Diet rich in complex, unrefined carbs, high in fiber
(14 g/1000
cal consumed daily), and low in added sugar (<25% of caloric
intake)
Recommended by Diabetes Prevention Program
Fat
Saturated fat <7% of caloric intake
Increase of unsaturated fat
linoleic acid should be 5-10% of caloric intake (i.e. safflower oil)
alpha-linolenic acid 0.7-1.6% of calories (i.e. kiwifruit seeds and flax)
Lifestyle Modifications
Sodium
DASH (Dietary Approaches to Stop Hypertension)
Restrict sodium intake to no more than 1500 to 2000mg/day
Lifestyle Modifications
Physical activity
Improves glucose transport and insulin action in
working skeletal muscle
AHA guidelines on exercise
≥ 30 min/day most days of the week (brisk activity; 5 days)
Dose-response effect of aerobic exercise on visceral
adiposity
7-10% reduction in BW during one year of therapy
Pharmacologic Therapy
Lifestyle modifications can have amazing clinical
benefits… but often met with failure
Noncompliance
Journal keeping and classes?
Excess adiposity
Currently only one FDA drug approved for long term
management – Orlistat (Rx - Xenical, OTC - Alli)
The National Institutes of Health guidelines
BMI ≥ 30 kg/m2
Pharmacologic Therapy
Insulin resistance/hyperglycemia
First line treatment
1.
2.
3.
•
•
4.
•
5.
Weight loss – 5-10% of baseline weight
Lifestyle modifications
Metformin – indicated for patients with both impaired
fasting glucose (IFG) and impaired glucose tolerance (IGT)
DPP study found metformin reduced progression of diabetes
by 31% for those at risk (53% whom had MetS)
Also reduced incidence of MetS by 17%
Pioglitazone – increase BW, but reduces waist to hip ratio
Improves: BP, TGs, HDL-C, carotid intima-media thickness
Acarbose – STOP-NIDDM trial – many benefits, but very
poor patient tolerability (FLUTALANCE, abdominal pain)
Pharmacologic Therapy
Dyslipidemia
Elevated TGs, low HDL-C, and small, dense LDL-C
MetS is not currently a coronary risk equivalent for
managing lipid goals
Calculate LDL goal and secondary Non-HDL goal using
ATP III guidelines
Very high risk – LDL < 70 mg/dL
Moderate high risk LDL < 100 mg/dL
Moderate risk LDL < 130mg/dL
Pharmacologic Therapy
Dyslipidemia – treatment
1. Statins
Reduce LDL-C 15 to 60%
•
Increase HDL-C 5 to 10%
•
Reduce triglycerides 7 – 30%
•
Pleiotropic effects on inflammation, endothelial function,
and CVD events
•
4S* trial- Those with MetS had both the highest risk of
major coronary events and the greatest benefit from statin
therapy
*Scandinavian Simvastatin Survival Study
•
Pharmacologic Therapy
Dyslipidemia
Bile acid sequestrants (Welchol, Questran, Colestid)
LDL-C reduction of 15 to 30%
Ezetimibe (Zetia)
LDL-C reduction of 15 to 25%
***CONTROVERSY***
ENHANCE study showed no differences in carotid intima-media
thickness when given with simvastatin; no reduction in events…
ARBITER 6-HALTS trial
Showed that ezetimibe increased carotid intima-media artery
wall thickness compared to niacin
SHARP study – Simvastatin and ezetimibe in renal disease
Upcoming IMPROVE-IT Trial
Pharmacologic Therapy
Dyslipidemia
Fibrates
Reduce triglycerides 25 to 50%
Increase HDL-C 5 to 15%
Reduce LDL 0 to 30%
Useful to reach non-HDL-C goal when statins are not enough
Niacin
Most effective FDA approved agent for raising HDL-C and increasing HDL-C particle
size
15-35%
Lowers TGs 20 to 50%
Reduction of LDL-C 5 to 25%
Note: caution in liver dx, gout, DM (hyperglycemia and hyperuricemia)
AIM-HIGH trial – halted prematurely
No benefit over statin alone in reduction CV related complications, despite
increases in HDL and decreases in triglycerides
A small and unexplained increase in ischemic stroke rates in high dose niacin
group
Pharmacologic Therapy
• Hypertension/Elevated Blood Pressure
• First line – in patients with MetS, especially in setting of
CVD or T2DM
1.
2.
A.
•
•
Angiotensin-converting enzyme (ACE) inhibitors
Angiotensin receptor blockers (ARB)
Shown to be effective in reducing rates of albuminuria or
progression of nephropathy in patients with diabetes
Thiazide type diuretic
ALLHAT* trial – superior CVD outcomes compared to CCB,
B-B, or ACE-I; even in diabetes
*Antihypertensive and Lipid-Lowering Treatment to Prevent
Heart Attack Trial
Pharmacologic Therapy
Antiplatelets (ASA)
Treating the prothrombotic state of MetS
low-dose aspirin reduces CVD events in both secondary
and primary prevention
Favorable efficacy/side effect ratio when 10-year risk for
CVD is ≥10%.
AHA/ACC class 1b recommendation for women less than
65 years old with intermediate risk
Bariatric Surgery
In a recent meta-analysis of 22,094 morbidly obese
patients:
T2DM resolved in 76.8% and improved in 86% of cases
Swedish Obese Subjects study – 10 year follow up
surgery
Overall reduction in mortality due to CVD and T2DM
Associated with improvement and/or resolution of
multiple comorbidities associated with obesity
Controversy About MetS
1. The definition
2. The ability or inability of MetS to predict CVD or
T2DM
•
Should T2DM be part of the definition?
Is MetS greater than the sum of its parts?
•
•
•
Weakness:
•
•
i.e. greater risk than its individual abnormalities
Treatment is no different than treatment for each of its
components
NCEP ATP III associates MetS with a 2-fold increase in
CVD
Conclusion
Treatment strategies must focus on identifying and
managing individual components of metabolic
syndrome
Aggressive therapy must be optimized for each
individual patient and characteristics to reduce risk
No direct marker for insulin resistance to diagnose
metabolic syndrome
Further research is needed to better define metabolic
syndrome, the exact pathophysiology, and treatment
algorithms
Use care with lipid lowering agents
References
Prasad, H, et al. Metabolic Syndrome: Definition and
Therapeutic Implications. Postgraduate Medicine 2012; Jan. vol.
124, issue I. Pg. 21-30.
Well, CC, et al. Obesity, race, and risk for death or functional
decline among Medicare beneficiaries. Annals. 2011 May; Vol 154,
num 10: 645-654.
SHARP Collaborative Group. Study of Heart and Renal
Protection (SHARP): Randomized trial to assess the effects of
lowering low-density lipoprotein cholesterol among 9438
patients with chronic kidney disease. Am Heart J 2010;
DOI:10.1016/j.ahj.2010.08.012.
The AIM-HIGH investigators. Niacin in patients with low HDL
cholesterol levels receiving intensive statin therapy. N Engl J
Med2011; DOI:10.1056/oa1107579
References
Taylor AJ, Villines TC, Stanck EJ, et al. Extended-
release niacin or ezetimibe and carotid intima-media
thickness. N Engl J Med 2009;
DOI:10.1056/NEJMoa907569
National Health Disparities Research Center of
Excellence Meharry Medical College. Cardio
Metabolic. Accessed March 2012.
http://www.hdrcoe.org/CardioMetabolic.html
Bruce Goldfarb. Metabolic Syndrome Debate Defused.
Diabetes Journals. March 2012.
http://docnews.diabetesjournals.org/content/3/9/1.1.f
ull
References
Expert Panel On Detection, Evaluation, And Treatment Of High
Blood Cholesterol In Adults (May 2001). "Executive Summary of
the Third Report of the National Cholesterol Education Program
(NCEP) Expert Panel on Detection, Evaluation, and Treatment
of High Blood Cholesterol in Adults (Adult Treatment Panel
III)". JAMA: the Journal of the American Medical
Association 285 (19): 2486–9
Ashen, DM. Management of cardiometabolic syndrome in the
primary and secondary prevention of cardiovascular disease.
Journal for Nurse Practitioners. 2008;4(9):673-680.
Metabolic syndrome shown to increase risk of kidney problems.
Worldwide-Medicine.com. Aug 26, 2011. Accessed 10 March 2012.
http://www.worldwide-medicine.com/diseasesconditions/metabolic-syndrome-shown-to-increase-risk-ofkidney-problems/
References
Sulaiman N, Mahmood DA. Cardiometabolic
Syndrome. HOD Family and Community Medicine,
Sharjah University of Melbourne. Access 10 March 2012.