MAY 15th 2009 Issue AAFP JOURNAL REVIEW
AAFP JOURNAL REVIEW • Resistant hypertension • SIDS • Latent TB infection • High Quality Review articles
MCQ 1. Which of the following is/are true with regard to high quality review articles? • A. The review may have included German and Chinese language articles • B. Usually authored by renowned experts in the field • C. Local studies and unpublished studies are included • D. Review articles with an evidence table listing recommendations are best
High Quality Review articles • Validity of the research design leads to the level of evidence assignment • Relevance of the study with regard to patient oriented outcomes determines strength of recommendation • Beware of Experts. Increasing expertise of the author is correlated with lower methodologic quality of the review
High Quality review articles • CONCLUSION: • use sources that use the SORT system
Resistant Hypertension • DEFINITION: BP not at target despite adherence to 3 or more optimally dosed medications of different classes, incl. diuretic. • 65million Americans have HTN • 40million BP not at target • Prevalence of true resistant HTN unclear • “Resistant HTN” is subset of “difficult-to-control HTN ”
Difficult to Control HTN • Most common cause: suboptimal treatment • Patient factors: non-adherence • Physician factors: inertia; acceptance above goal; not knowing “true” BP • Assess adherence to TLC and medications • R/O white coat HTN (home BP, consider confirmation with 24h ambulatory BP) • Average 24h BP > 130/80, or average daytime>135/85 → intensify therapy
Measurement issues • Cuff too small • Severe arteriosclerosis : pseudo-HTN • Suspect pseudo HTN if: • radial pulse palpable with cuff fully inflated, • dizziness/weakness in elderly following anti-HTN meds
Adherence issues • DASH + low Na, equally effective as 1 drug • Importance of weight loss • Daily aerobic exercise • Moderate etoh • Non judgmental inquiry into drug adherence • Factors: economic, health literacy, language, side-effects • Fixed dose combination/once daily may improve adherence (but beware of ↑ cost) • Simplest regimen: diuretic/Ace-combo + a 3rd once-daily agent (eg long-acting CCB)
Associated factors • Isolated systolic HTN in elderly: it is OKAY to lower diastolic to 70mmHg • Octogenarian on anti-HTN meds have reduced morbidity and mortality • Obesity: Na/fluid retention, RAAS-stimulation • Obesity treatment: - 1kg Wt reduction = 1-2.4mmHg BP - diet, orlistat, bariatric surgery • Reduce etoh intake
Causes of Resistant HTN • CKD • OSA • Hyperaldosteronism • Common factor in the above: fluid retention • Obesity • Etoh • High dietary sodium • Interfering drugs, eg NSAIDS (incl COX2), OCP, bupropion, sudafed, cocaine, appetite suppressants, amphetamines, herbals(Ginseng)
Truly Drug-Resistent HTN • Volume overload (eg CKD, ↑ NA-intake, obesity, OSA, hyperaldosteronism) • Ensure adequate diuretic therapy (chlorthalidone rather than HCTZ) • If cr >1.5-1.8, or GFR<30 switch to loop diuretic • Give short acting loop diuretic BID
Secondary HTN • CKD. Na-restriction!, Diuretic, ACE/ARB Check K, cr 2 wks after start of ACE/ARB 30% rise in cr, K up to 5.5 are acceptable • Hyperaldosteronism. 20% of referred patients. K can be normal. AM aldosterone/renin ratio < 20 rules out. Ratio>20 or aldosterone>15 → refer to endocrinology or HTN specialist. • Primary hyperaldosteronism– treat with spironolactone, eplerenone(Inspra) or amiloride(Midamor). Monitor cr., K.
Secondary HTN • OSA. Difficult to control HTN can be the only sign. Unexpectedly found in 83% of patients in 1 study of DTC-HTN
Pharmocologic options • Spironolactone (up to 20/10mmHg reduction) • α- blocker(terazosin) • α/β blocker(labetalol, carvedilol) • Clonidine, reserpine or hydralazine • Combine a non-dihydropyridine + dihydropyridine CCB • Minoxidil • Avoid ACE/ARB combo → improves proteinuria, but worsens major renal outcomes
MCQ 1. Which one of the following is a cause of truly drug-resistant hypertension? • A. Volume overload. • B. Physician inertia in prescribing. • C. Costly or complex medication regimens. • D. Pseudohypertension.
MCQ 7. Which of the following is/are causes of apparently difficult-to-control hypertension? (check all that apply) • A. Nonadherence to therapy. • B. Obstructive sleep apnea. • C. White-coat hypertension. • D. Severe arteriosclerosis.
MCQ 8. Which of the following is/are treatment options for drug-resistant hypertension? • A. Optimizing diuretic dose and adding spironolactone (Aldactone). • B. Assessing for and treating obstructive sleep apnea. • C. Giving both an angiotensin-converting enzyme inhibitor and an angiotensin receptor blocker. • D. Adding a combined alpha-beta blocker.
SIDS Definition • DEFINITION (1991): sudden death of an infant < 1yo, that remains unexplained after thorough case investigation, including complete autopsy, death scene examination and clinical history review.
SIDS • Leading cause of death under healthy infants • 0.57/1000, 2200/year • Modifiable RFs: sleeping position, cigarette smoke exposure • ALTE does NOT increase risk of SIDS • Home apnea monitoring does NOT reduce SIDS
SIDS Risk Factors Infant factors Maternal factors Low socioeconomics Smoking Illicit drug use Poor prenatal care Young age Single parent Unemployed Crowded household • Low birth weight • Low apgar scores • Recent viral illness • Native American • African American • Male sex
SIDS prevention • Back to Sleep → decreased SIDS cases, but prone sleeping remains presumptive cause. • AA babies more often placed in prone position • Firm mattress • Avoid soft objects, loose bedding • Avoid overheating • Pacifier . Wait till >1month old for breastfed babies
Pathophysiology • 3 common autopsy findings: unclotted blood in heart, intrathoracicpetechiae, fluid filled heavier organs • “Apnea theory” discredited • “Triple-risk model”: + underlying vulnerability (unidentified) + exogenous stress (eg prone sleeping) + critical developmental period (< 1yo)
SIDS research topics • Ion channel abnormalities causing QT prolongation. 5-10% of SIDS cases? • Autonomic nervous system disturbance 2/2 gene mutations. Arousal mechanism defects. 15% of cases? • Pre- & postnatal nicotine effects on developing brain. Nicotine metabolizing gene defects? Exposure a/w SIDS, prematurity, autonomic dysfunction, LBW, spontaneous abortion,
SIDS prevention/counseling • 92% of cases in prone sleeping, bed sharing, sleeping in other location than crib • Back to Sleep campaign 50-70% reduction • Bedsharing – discouraged by AAP 2005 • Bedsharing (50% of cases) – increased risk in LBW infant, smoking, etoh, drugs. • Bedsharing > 4 months old: no risk • Infant never to sleep with other children, with adult on couch or armchair • Infant to sleep in separate crib near mom’s bed
Deformational plagiocephaly • Flattening of the occiput • 50% of supine sleepers • Give supervised “tummy time” • Alternate rotation during sleep times • Do not use car seat unless in car • Minimize devices with pressure to back of head (swing, bouncy seat) • If DP present: do not sleep on flat side, PT if torticollis, NEU-surgeval PRN in no improvement with head positioning s
Immunizations • Some case control studies : lower SIDS rate among fully immunized. • Confounders: socioeconomic status? Other risk factors?
Apnea • No risk of SIDS • Home apnea monitor no risk of SIDS • Pacifier at bedtime does risk of SIDS (AAP 2005) • Delay pacifier to 1 month of age for breastfed babies
ALTE-s • Apparent Life Threatening Event • s in skin color (cyanosis, pallor, erythema) s in muscle tone & choking or gasping • 1:400 infants • “ near-miss-SIDS” - incorrect term • SIDS campaign has not reduced ALTE incidence • common RF for SIDS & ALTE: prenatal smoking, single parenthood
ALTE risk factors • H/O apnea, cyanosis, pallor • H/O feeding difficulties • Single parenthood • F/H of infant death • Maternal smoking in pregnancy
ALTE etiology • Etiology determined in 50% • Diagnosis by H&P • Potentially useful tests: reflux testing, UA, Neu imaging, CXR, WBC • GI/ GERD most common • Respiratory infections • Minority of cases: valvular disease, arrhythmia, cardiomyopathy • Rare: NEU cause: tumor, structural brain abnormailities, Sz D/O • Recurrent ALTEs- high incidence of Munchausen by proxy
SIDS differential diagnosis • Infection, electrolyte abnormalities, inborn errors of metabolism, abuse • Investigation: death scene evaluation – infant’s position, bedding, bed, body temp, room temp, rigor?, type of heating/cooling, caregiver response • Intentional suffocation estimated 1-5% of cases
SIDS differential diagnosis • Suspicion of intentional suffocation if lone caretaker, infant death > 6 months, unexplained death of siblings, simultaneous death of twins, previous death of child under care of same person
SIDS support & counseling • Empathy/compassion • Support through process of death investigation • Guide through ending lactation, funeral planning • Grief counseling • SIDS support groups • Risk of future children dying from SIDS not
MCQ 3. The parents of a newborn ask about risks associated with their infant sleeping in bed with them. Which one of the following statements is correct? (check one) • A. Infants who bed share with smokers have about the same risk of sudden infant death syndrome (SIDS) as infants who bed share with nonsmokers. • B. The risk of SIDS is not increased in a low–birth-weight infant who bed shares. • C. The American Academy of Pediatrics recommends against bed sharing. • D. Infants older than four months who bed share appear to be at greater risk of SIDS than younger infants.
MCQ 2. A two-month-old boy is rushed to the emergency department because he briefly turned pale, choked, and went limp. Which one of the following evaluations is most likely to lead to a diagnosis? (check one) • A. History and physical examination. • B. Testing for gastroesophageal reflux. • C. Neuroimaging. • D. Urinalysis.
MCQ 9. Which of the following practices is/are or may be protective against sudden infant death syndrome? • A. Keeping immunizations up-to-date. • B. Pacifier use. • C. Ante-partum smoking cessation. • D. Postpartum smoking cessation.