1 / 92

BIOE 301

BIOE 301. Lecture Three: Leading Causes of Mortality, Ages 15-44. Geoff Preidis MD/PhD candidate Baylor College of Medicine preidis@post.harvard.edu. Review of Lecture Two: Leading Causes of Mortality, Birth-Age 4. Developing world Perinatal conditions Lower respiratory infections

niveditha
Download Presentation

BIOE 301

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BIOE 301 Lecture Three: Leading Causes of Mortality, Ages 15-44 Geoff Preidis MD/PhD candidate Baylor College of Medicine preidis@post.harvard.edu

  2. Review of Lecture Two:Leading Causes of Mortality, Birth-Age 4 • Developing world • Perinatal conditions • Lower respiratory infections • Diarrheal diseases • Malaria • Developed world • Perinatal conditions • Congenital anomalies • Lower respiratory infections • Unintentional injuries

  3. 1. Perinatal Conditions • Question: What is the #1 way to prevent septicemia in a newborn in the developing world?

  4. 1. Perinatal Conditions http://www.path.org/projects/clean-delivery_kit.php

  5. 2. Lower Respiratory Infections • Question: How can a busy health worker (or a parent) quickly screen for pneumonia in a child?

  6. 2. Lower Respiratory Infections

  7. 3. Diarrheal Diseases • Question: What is the #1 way to prevent diarrheal illness in a newborn?

  8. 3. Diarrheal Diseases

  9. 4. Malaria • Questions: 1. Why has malaria been eradicated from the southern U.S.? How can these principles be applied to less developed countries?

  10. 4. Malaria • Reduced human/insect contact • Prevent mosquito breeding • Use insect repellents, mats, coils • Residual treatment of interior walls • Wear long sleeves/pants • Insecticide-treated mosquito bed nets • Treatment of those who have malaria prevent its spread! • Questions: 2. What are the challenges for implementing this technology in developing countries?

  11. 4. Malaria • What are the challenges for implementing this technology in developing countries? • Mapping areas that are difficult to access • Poor communication • Direction – Transfer of vector control efforts from malaria control authorities to local primary health care center • Financial support – decreased standard of living from wars, environmental factors, migration • Corruption, graft • Questions: 3. Where is the malaria vaccine?

  12. 4. Malaria • Where is the malaria vaccine? • Funding • Thousands of antigens presented to the human immune system -> which ones are useful targets? • Plasmodium has many life stages -> different antigens at each stage • Plasmodium has several strategies to confuse, hide, and misdirect the human immune system • Multiple malaria infections of the different species and different strains of the same species may occur in one host! http://www.cdc.gov/malaria/images/graphs/malaria_lifecycle.gif • Questions: 4. How does Chloroquine protect you when you travel?

  13. 4. Malaria http://sickle.bwh.harvard.edu

  14. Leading Causes of Mortality Ages 15-44 • Developing World • HIV/AIDS • Unintentional injuries • Cardiovascular diseases • Tuberculosis • Developed World • Unintentional injuries • Cardiovascular diseases • Cancer • Self-inflicted injuries

  15. 1. HIV/AIDS • Burden of HIV/AIDS • Pathophysiology of HIV • Clinical course of HIV/AIDS • Highly Active Antiretroviral Therapy • Historical Perspective of HIV/AIDS • Discussion: Is HAART really feasible in developing countries?

  16. Burden of HIV/AIDS • Worldwide • 39.5 million people are living with HIV/AIDS • 20 million people have been killed by the disease • 2006: • 2.9 million deaths • 4.3 million new HIV infections (400,000 more than in 2004) • 40% of new infections occurred in young people (ages 15-24) • 2/3 of those with AIDS and 3/4 of all AIDS deaths are in sub-Saharan Africa • In the past 2 years, the number of HIV-infected people rose in every region in the world Source: 2006 AIDS Epidemic Update, UNAIDS/WHO

  17. AIDS has Reduced Life Expectancy

  18. Burden of HIV/AIDS • United States • 1.2 million people have HIV/AIDS (prevalence) • 30,000-40,000 new infections per year (incidence) • Only 7 countries in the world have more people living with HIV than the U.S. • Routes of transmission: • Unsafe sex between men (44%) • Unprotected heterosexual intercourse (34%) • Non-sterile drug injection equipment (17%)

  19. Burden of HIV/AIDS in the U.S. • Racial and ethnic minorities are disproportionately affected: • 50% of AIDS diagnoses are in African-Americans (12% pop) • 20% of AIDS diagnoses are in Hispanics (14% pop) • The rate of new HIV diagnoses was 21x higher in African-American women than in white women • Women are increasingly affected: • The proportion of of women among new HIV/AIDS diagnoses have risen from 15% to 27% in 10 years • Question: Why is the total number of HIV infected people in the U.S. continuing to increase?

  20. Burden of HIV/AIDS in the U.S. • Anti-retroviral therapy has accounted for an 80% decrease in AIDS death rates in the last decade • Annual cost to treat: $15 billion

  21. Pathophysiology of HIV/AIDS HIV Structure Envelope Proteins gp120 Envelope gp41 Matrix Proteins p17 Core Proteins p14 RT RNA Integrase Protease http://bayloraids.org/curriculum/

  22. Pathophysiology of HIV/AIDS http://bayloraids.org/curriculum/

  23. Pathophysiology of HIV/AIDS http://bayloraids.org/curriculum/

  24. Clinical Course of HIV/AIDS • HIV Infection • Spread by sexual contact with infected person or sharing needles with infected person or by transmission from mother to child • Virus deposited on mucosal surface • Acute infection (flu like symptoms) • Viral dissemination • HIV-specific immune response • Replication of virus • Destruction of CD4+ lymphocytes • Rate of progression is correlated with viral load • Latent Period

  25. Clinical Course of HIV/AIDS

  26. Clinical Course of HIV/AIDS http://hivinsite.ucsf.edu/topics/aids_basics

  27. Clinical Course of HIV/AIDS http://bayloraids.org/curriculum/

  28. Clinical Course of HIV/AIDS • AIDS • Immunologic dysregulation • Opportunistic infections and cancers • Risk of infections is correlated with number of CD4+ lymphocytes • Average patient with AIDS dies in 1-3 years • Within 10 years of infection (w/o Rx): • 50% of patients develop AIDS • 40% develop illness associated with HIV • 5-10% remain asymptomatic

  29. Clinical Course of HIV/AIDS

  30. HIV/AIDS Therapy • Reverse Transcriptase Inhibitor enzymes (1987) • Enzyme is specific to HIV • Combinations of RTIs appear effective • HIV Protease Inhibitors (1995) • HIV proteases are distinct from mammalian proteases • Most significant advance in HIV therapy yet • Highly Active Antiretroviral Therapy (HAART) • Combination of three or more drugs • Fusion inhibitors (2003) • Subject of new research

  31. HIV/AIDS Therapy • HIV can rapidly mutate to quickly develop resistance to a single drug • Resistance develops much more slowly to drug combinations • Goal of HAART: • Reduce viral levels to undetectable levels • Has reduced death rate in US and Europe by 80%

  32. HIV/AIDS Therapy http://www.aids-ed.org

  33. 6 million people living with AIDS in developing countries are in need of HAART. 90% are in just 34 countries http://www.npr.org/templates/story/story.php?storyId=4724368

  34. HIV/AIDS Therapy • Prevention of Mother to Child Transmission (PMTCT) • 3 routes of transmission: • Parentally (during pregnancy) • Perinatally (during delivery) • Breast feeding (through milk) • 4 Core interventions: • HIV testing and counseling • ARV prophylaxis (ZDV, NVP) • Safer delivery practices • Safer infant-feeding practices • Reduces transmission from 30-40% to 4-6%

  35. HIV/AIDS Historical Perspective • 1981 • CDC reported unexplained PCP in 5 previously healthy, homosexual men • CDC reported Kaposi’s sarcoma in 26 previously healthy, homosexual men • 1981-1982 • Increased association with IV drug use, recipients of blood transfusions, hemophiliacs • 1983 • Virus isolated

  36. HIV/AIDS Historical Perspective • August 23, 1982 • “‘Homosexual Plague’ Strikes New Victims” • Cites evidence from the CDC • “The 4-H Club”

  37. HIV/AIDS Historical Perspective • 1985 • ELISA approved, began screening U.S. blood supply • 1987 • AZT (RTI) approved by FDA, costs $12,000 per year • 1995 • First Protease Inhibitor approved, makes HAART possible • 2003 • First Fusion Inhibitor approved • 2005 • NIH funds CHAVI (Center for HIV/AIDS Vaccine Immunology) • Today • NRTIs, NNRTIs, Protease Inhibitors, Fusion Inhibitors • Integrase Inhibitors??? Vaccine development???

  38. Discussion “For the average AIDS patient in developing countries… therapy is an inaccessible dream, and merely a diversion for developing country health ministries from more pressing concerns which threatens more cost-effective programs against HIV.... Since nothing will likely bridge this gap between poor and rich countries, only prevention and a vaccine will likely make a real difference for the poor in the battle against HIV/AIDS.” --Hirschel B, Francioli P. Progress and problems in the fight against AIDS. NEJM 1998 Mar 26;338(13):853-60.

  39. 2. Unintentional Injuries

  40. 2. Unintentional Injuries • Burden of Unintentional Injuries • Accident Physics • Slowed Driver Reaction Time • Prevention of Road Accidents

  41. Burden of Unintentional Injuries • More than 1.25 million people ages 15-44 die from unintentional injuries each year • 1 million deaths in developing countries, 1/4 million in developed countries • 40x this number are injured • Major cause of disability • Leading cause is road accidents: • 500,000 deaths per year in this age group • 90% of these deaths occur in developing countries

  42. Burden of Road Accidents in the US • Rates declining steadily • A leading cause of potential years of life lost • 2004: • 42,636 Americans killed • 2,788,000 Americans injured • Fatal accident rates >4X higher for males than for females • Motorcycles: 40X higher death rate per mile traveled • 39% of fatalities related to alcohol use

  43. Accident Physics • Newton’s 2nd Law: • F = m a • a = dv/dt • a = initial velocity/time to come to rest • In a crash: • Velocity slows to zero in a very short time • Generates large forces • How can we reduce these forces? • Reduce initial velocity of impact • Extend time that it takes passengers to come to rest

  44. Accident Physics 1. Reduce initial velocity of impact • Excessive speed contributes to: • 30% of deaths in developed countries • 50% of deaths in developing countries

  45. Slowed Driver Reaction Time • When drivers anticipate a crash, they have time to brake and reduce initial velocity • Factors which slow driver reaction time: • Alcohol use • Mobile phone use • Poor visibility • Driver inexperience

  46. Slowed Driver Reaction Time • Alcohol impaired drivers have 17X increased risk of being in fatal crash • Alcohol use increases risk more in younger drivers • 1 in 5 Americans will be involved in an alcohol-related crash at some time in their lives • TX BAC limit: • 0.08+ g/dl is illegal • Approx 3 drinks in a 140 lb individual • Significant driving impairment at just 0.04 BAC!

  47. Slowed Driver Reaction Time • Mobile phone use: • At any given daylight moment in US: • 10% of drivers are using a cell phone • Increases driver reaction time by 0.5-1.5 sections • Risk of crash is 4X higher when using a mobile phone • Same as driving with a BAC of 0.09 g/ dl • 4 states and D.C. have banned use of hand held phones while driving (NY, NJ, CT, CA) • Partial bans in AR, AZ, FL, GA, IL, ME, MA, MN, NH, NM, OH, PA, TN, VA

  48. Prevention of Road Accidents 2. Extending Time to Come to Rest: • Crumple zones • Allow passengers additional time to decelerate • Seat belts • Keep occupants in the passenger compartment • Stretch during impact • Reduce risk of death in crash by 40-60% • http://www.regentsprep.org/Regents/physics/phys01/accident/nobelt.htm • http://www.regentsprep.org/Regents/physics/phys01/accident/withbelt.htm • Air bags • When combined with seat belts, reduce risk of serious and fatal injuries by 40-65% • http://www.nhtsa.dot.gov/staticfiles/DOT/NHTSA/Communication%20&%20Consumer%20Information/Multimedia/Associated%20Files/crashdum2.ram • http://www.accidentreconstruction.com/movies/5thper.mov • Child restraints: • Reduce risk of infant death by 71% and toddler death by 54% • http://www.nhtsa.dot.gov/staticfiles/DOT/NHTSA/Communication%20&%20Consumer%20Information/Multimedia/Associated%20Files/crashdum3.ram

  49. Prevention of Road Accidents • Legislation: • Speed • Seat belts, Car seats, Air Bags • Alcohol use • Motorcycle helmets • Engineering: • Restraints • Safety standards • Education: • Seat belts, Car seats, Air Bags • Alcohol use

More Related