Presentation on theme: "به نام خدا ارزیابی سلامت میانسالان دکتر رضا خدیوی دانشیار گروه پزشکی اجتماعی."— Presentation transcript:
به نام خدا ارزیابی سلامت میانسالان دکتر رضا خدیوی دانشیار گروه پزشکی اجتماعی
غربالگری Disease screening usually takes two general forms: (a)Screening for proven, biological, or behavioral risk factors for diseases that lead to interventions or treatments in themselves, such as abnormal blood cholesterol or blood pressure levels; (b) screening directly for evidence of the disease itself, followed by provision of effective treatment to cure or to prevent the progression of pathophysiological processes that will cause overt clinical manifestations.
غربالگری Disease screening may be applied to: A)general populations irrespective of receipt of medical care (i.e., mass screening), or B) To clinical populations with various characteristics
غربالگری There are several criteria that aid in selecting and applying an appropriate screening test: (a) The disease should be common enough to warrant a search for its risk factors or latent stages because screening for excessively rare diseases may result in unacceptable cost-benefit ratios; (b) The morbidity or mortality (i.e., burden of suffering) of the untreated target condition must be substantial;
غربالگری C) An effective preventive intervention or therapy must exist and should not encumber a more beneficial outcome when applied to the presymptomatic rather than to the symptomatic stage; D) The screening test should be acceptable to the population and suitable for general, routine application. E) Many other criteria for an effective screening test could be added, such as maintenance of test accuracy over time and freedom from screening-related adverse effects.
غربالگری The operating characteristics of a screening test are its sensitivity and specificity. These are general test characteristics that can apply to any laboratory or diagnostic test data as well as other information collected from the medical history and physical examination. Sensitivity (%) = True positives / (True positives + False negatives)×100 Specificity (%) = True negatives / (True negatives + False negatives)×100
غربالگری Positive Predictive Value (%) =True positives/(True positives + False positives)×100 Negative Predictive Value(%)=True negatives/ (True negatives + False negatives)×100 Predictive values are dependent on both: A)The operating characteristics and B) The prevalence of the disease in the target population For any given set of operating characteristics, the positive predictive value is directly related to prevalence, and the negative predictive value is inversely related to prevalence. Therefore, in screening situations where the prevalence is relatively low, the operating characteristics must be very high to avoid low positive predictive values.
غربالگری Screening programs ( The tests and procedures selected )must be: 1 - cost-effectiveness. 2 - for use are often highly standardized 3 - can be administered more inexpensively than they can in clinical or more specialized settings, 4 - generally they can be applied without the need for direct physician supervision. 5 - To enjoy the efficiency of mass screening, such programs must be carefully organized and managed. 6 - Recipients of both normal and abnormal test results must be considered.
غربالگری 7 - Those with abnormal test results must have a properly organized follow-up evaluation protocol, 8 - Those with normal results should be informed of the predictive value of a normal test to avoid false reassurance. In 2006 the United States spent $2.1 trillion on health care. Less than 3% of this total was dedicated to government public health activities designed to prevent illness.
دسترسی به خدمات سلامت Access to health care is the ability to obtain health services when needed. Lack of adequate access for millions of people is a crisis in the United States. Access to health care has major components: A) First is ability to pay. B) Second is the availability of health care personnel and facilities that are close to where people live, C) Accessible by transportation, D) culturally acceptable, E) Capable of providing appropriate care in a timely manner F) In a language spoken by those who need assistance.
موانع مالی دسترسی به خدمات سلامت A)Lack of Insurance -Health insurance coverage, whether public or private, is a key factor in making health care accessible. Ninety million people, 30% of the entire US population, went without health insurance for all or part of the 2-year period 2006–2007. In 2002, 30% of the uninsured reported not being able to obtain needed health care in the past year because of costs and 28% reported not being able to afford needed medications.
موانع مالی دسترسی به خدمات سلامت The uninsured suffer 1)worse health outcomes than those with insurance. 2) have more avoidable hospitalizations; 3)they tend to be diagnosed at later stages of life-threatening illnesses, 4)they are on average more seriously ill when hospitalized. 5) Higher rates of hypertension and cervical cancer and 6) lower survival rates for breast cancer, 7) with less frequent blood pressure screenings, Pap smears, and clinical breast examinations. Most significantly, people who lack health insurance suffer a higher overall mortality rate than those with insurance.
Lack of Coverage for Long-Term Care The study found that cost sharing : 1)reduces the rate of ambulatory care use, especially among the poor, 2) reduction in both appropriate and inappropriate medical visits. 3) Decrease Pap smears screening to 65% as often as the free care group. 4) higher diastolic pressures in hypertensive adults 5) children had higher rates of anemia and lower rates of immunization.
NONFINANCIAL BARRIERS TO HEALTH CARE Nonfinancial barriers to health care include inability to access care when needed, language, literacy, and cultural differences between patients and health caregivers, and factors of gender and race. 53% of emergency department visits are not urgent and involve patients with insurance seeking prompt care because they are unable to obtain an appointment with their private physician.
NONFINANCIAL BARRIERS TO HEALTH CARE From 1997 to 2001, the percentage of people reporting an inability to obtain a timely appointment rose from 23% to 33%. In 2001, 43% of adults reporting an urgent condition were sometimes unable to receive care as soon as they wanted. A 2001 women’s health survey found that 28% of women in fair or poor health reported delaying care or failing to receive care because of an inability to obtain a timely physician appointment.
Gender and Access to Health Care Access problems for women often begin with finding a physician who communicates effectively. Women are 50% more likely than men to report leaving a physician because of dissatisfaction with their care. patients with insurance coverage for Pap smears and mammograms, the patients of female physicians were almost twice as likely to receive a Pap smear and 1.4 times as likely to have a mammogram than the patients of male physicians.
Gender and Access to Health Care Physicians are less likely to counsel women than men about cardiac prevention—diet, exercise, and weight reduction. After having a heart attack, women are less likely than men to receive recommended diagnostic tests and are less likely to be prescribed recommended aspirin and beta-blockers. Fewer than one-third of women of reproductive age have received counseling about emergency contraception, sexually transmitted diseases, or domestic violence.
Gender and Access to Health Care A study conducted in a managed-care medical group in California found that 70% of hysterectomies were inappropriate
FINANCIAL BARRIERS TO HEALTH CARE The gap between rich and poor has widened markedly in the United States. In 1986, people in the United States with a yearly income of less than $9000 had a death rate three to six times higher than those with a yearly income of $25,000 or more. In 2007,the mortality rate for heart disease among laborers is more than twice the rate for managers and professionals. The incidence of cancer increases as family income decreases, and survival rates are lower for low-income cancer patients. Higher infant mortality rates are linked to low income and low educational level.
FINANCIAL BARRIERS TO HEALTH CARE Not only does the income level of individuals affect their health and life expectancy, the way in which income is distributed within communities also appears to influence the overall health of the population. In the United States, overall mortality rates are higher in states that have a more unequal distribution of income, with greater concentration of wealth in upper income groups.
Prevention Methods -Primary prevention seeks to avert the occurrence of a disease or injury (e.g., immunization against polio; taxes on the sale of cigarettes). - Secondary prevention refers to early detection of a disease process and intervention to reverse or retard the condition from progressing (e.g., Pap smears and mammograms ).
Prevention Measures The promotion of good health and the prevention of illness encompass three distinct levels or strategies: The first and broadest level includes measures to address the fundamental social determinants of illness; lower income is associated with higher morbidity and mortality rates. Improvement in the standard of living and social equity (e.g., through job creation programs to reduce or eliminate unemployment) may have a greater impact on preventing disease than specific public health programs or medical care services.
Prevention Measures The second level of prevention involves public health interventions to reduce the incidence of illness in the population as a whole. water purification systems, the banning of cigarette smoking in the workplace, public health education on human immunodeficiency virus (HIV) prevention in the schools. These strategies generally consist of primary prevention.
Prevention Measures The third level of prevention involves individual health care providers performing preventive interventions for individual patients; these activities can be either primary or secondary prevention. - Screening and treatment of hypertension- Periodic breast examinations -Mammograms -Prenatal care
THE FIRST EPIDEMIOLOGIC REVOLUTION In the nineteenth century, scientists and public health practitioners discovered many of the agents causing infectious diseases. By comprehending the causes (such as bacteria and viruses) and the risk factors: (e.g., poverty, overcrowding, poor nutrition, and contaminated water, and food supplies) associated with these illnesses, public health measures (such as water purification, sewage disposal, and pasteurization of milk) were implemented that drastically reduced their incidence.
THE SECOND EPIDEMIOLOGIC REVOLUTION Eleven major infectious diseases accounted for 40% of the total deaths in the United States in 1900, but less than 10% in 1980. In contrast,heart disease, cancer, and stroke (cerebrovascular disease) caused 16% of the total deaths in 1900 but 64% by 1980. In 2004, 2.4 million people died in the United States. A surprisingly small number of risk factors are implicated in 38% of these deaths. It has been estimated that use of tobacco causes 435,000 fatalities, a high-fat diet and inactivity contributes to 400,000 more, and alcohol is responsible for 85,000 deaths annually in the United States
THE SECOND EPIDEMIOLOGIC REVOLUTION By discovering and educating the population about the risk factors of smoking, rich diet, and lack of exercise, the second epidemiologic revolution has already been very successful. From 1980 to 2004, age-adjusted mortality rates for coronary heart disease (CHD) declined by an astonishing 57%. This decline was associated with reduced rates of tobacco use and lowered mean serum cholesterol levels in the population. The unfortunate side of this success story is that those with the least education have considerably higher mortality rates than those with more education.
INDIVIDUAL OR POPULATION? Chronic disease prevention may be viewed from two distinct perspectives: 1 - That of the individual 2 - That of the population The medical model seeks to identify high-risk individuals and offer them individual protection, often by counseling on such topics as smoking cessation and low-fat diet.
INDIVIDUAL OR POPULATION? The public health approach seeks to reduce disease in the population as a whole, using such methods as mass education campaigns to counter drinking and driving, the taxation of tobacco to drive up its price, and the labeling of foods to indicate fat and cholesterol content.
INDIVIDUAL OR POPULATION? In the United States, most people with high cholesterol levels remain healthy for years, and some people with low levels have heart attacks at an early age. Why is this so? - CHD is the most likely cause of death. - Everyone in the United States is at risk for this disease. A “low” cholesterol level of 180 mg/dL is low by United States standards, but high when compared with levels in poor nations. A large number of people at small risk for a disease may give rise to more cases of the disease than the smaller number of people who are at high risk.
Beneficiaries following interventions A public health approach (e.g., mass educational campaigns on the health effects of rich diets and the labeling of foods) strives to reduce the mean population cholesterol level. A 10% reduction in the serum cholesterol distribution of the entire population would do far more to reduce the incidence of heart disease than a 30% reduction in the cholesterol levels of those relatively few individuals with counts greater than 300 mg/dL.
MODELS OF PREVENTION Coronary Heart Disease CHD is associated with four major risk factors: - the eating of a rich diet, -elevated levels of serum cholesterol, -cigarette smoking, and - hypertension. Primary CHD prevention involves risk factor reduction, including cessation of cigarette smoking, replacement of rich diets by low-fat diets, and control of hypertension. These strategies have been largely responsible for the large decrease in CHD death rates.
MODELS OF PREVENTION Cigarette Smoking- Between 1965 and 2004, the age-adjusted percentage of adult men who were current smokers dropped from 51% to 23%; for adult women, the decline was from 34% to 19%. These reductions in smoking prevalence have avoided an estimated 3 million deaths (a major public health achievement). Cigarette smoking declined 36% among the least educated persons, while it dropped 63% among the most educated. In 2004, 29% of the least educated persons smoked cigarettes, compared with only 10% of the most educated.
Cigarette Smoking At least 70% of smokers visit a health care setting each year; controlled trials suggest that physician counseling can influence smokers to quit. However, only 15% of smokers report that their physician offered them assistance to quit.
Rich Diet Lowering cholesterol levels has been shown to reduce the risk of heart attacks caused by CHD. The use of statin drugs to treat hyperlipidemia in people with known CHD (secondary prevention) and without CHD (primary prevention) has been shown to reduce deaths from CHD and deaths from all causes. However, the effectiveness of drug treatment is far greater if it is used in secondary rather than primary prevention.
Hypertension Individuals with systolic blood pressures of 130 to 140 mmHg have almost twice the cardiovascular risk of those with systolic blood pressures less than 110 mmHg. A quarter of hypertension- related cardiovascular deaths take place among borderline hypertensives, and in the United States, 90% of men aged 35 to 57 years have blood pressure levels that create excess cardiovascular risk.
Hypertension The greatest impact in reducing hypertension-related CHD mortality rates will come from a reduction in the blood pressure of the large number of borderline hypertensives rather than from focusing solely on people with very high blood pressure. Primary prevention of high blood pressure can be accomplished by: A)Reduction in the dietary salt intake(50%), B)Reduction in average body weight of 10%, C)The elimination of heavy alcohol intake. These three measures would lower the mean systolic blood pressure of the population by 5.4 mmHg, which in turn would reduce CHD deaths by 9% and stroke deaths by 14%.
Breast Cancer Between 1990 and 2004, cancer mortality rates trended downward, probably as a result of reductions in cigarette smoking. Breast cancer mortality rates began to decrease during the 1990s, However, only one-fourth of breast cancer cases can be accounted for by these risk factors. The differences between high and low age-adjusted breast cancer risk in the United States are small compared with the differences between such high-incidence nations as the United States and low-incidence (generally underdeveloped) nations.
Breast Cancer The age-adjusted incidence (new cases) of breast cancer fell sharply in 2003 compared with 2002, a phenomenon temporally related to the drop in the use of hormone replacement therapy by women in the United States, One study estimated that toxic chemicals encountered at workplaces are responsible for 20% of all human cancers. Estrogens have been used as additives to poultry and cattle feed, and pesticide residues contain estrogen-like compounds that may contribute to breast cancer causation.
Breast Cancer Some studies have linked breast cancer risk to organochlorine insecticides, polycyclic aromatic hydrocarbons, and organic solvents, Lack of knowledge has forced modern medicine to retreat to secondary prevention (i.e., early diagnosis through breast examinations and mammography) to reduce mortality rates in women with the disease. Regular breast examinations by a health care provider plus periodic mammograms can reduce breast cancer mortality rates in women aged above 50 years by one- third.