Public Health: Principlesand Practice

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Public Health: Principlesand Practice

Bruce Lubotsky Levin and Peter D. Hurd

CASE SCENARIO

You are a volunteer member of a community planning group in a local health department. As a health professional, the group seeks your guidance and leadership in its discussions and deliberations. As a health care professional, you are motivated to help develop successful programs that will reflect favorably on you, your community, and the pharmacy for which you work. The community is concerned about the increasing rate of human immunodeficiency virus (HIV), and your planning group wants to develop a community intervention program that will promote the adoption of reduced-risk practices in selected target populations. These at-risk populations include injection drug users (and their partners), men and women who engage in high-risk sexual practices, and undetected and untreated HIV infection in pregnant females. Your resources include an established volunteer group associated with the health department, local volunteer and support group organizations that are already involved in HIV-related or AIDS-related activities, and a modest printing budget for health education materials. Some members of the public health department could work for 20 hours per week as staff for the project. Barriers include a community that has shown some reluctance to become involved in HIV activities, a lack of resources dedicated to the project, your employer’s concern about balancing the benefits of becoming involved with community public health issues and the risks of los-ing customers, target populations that may be more difficult to reach through some of the traditional media, and a limited amount of time that committee members can dedicate to the project. Because of the nature of your community and your personal association with pharmacy, an evaluation of the program—hopefully to demonstrate success—is an important component of the project. What would you recommend? What process would you use to develop the program? How would you measure theoutcomes?

LEARNING OBJECTIVES

Upon completion of this chapter, the student shall be able to:

•define public health, prevention, and epidemiology;

•differentiate the focus of clinical medical care practice and public health practice;

•discuss the roles of pharmacists within managed health care; and

•give specific examples of emerging public health issues pharmacists face in clinical practice.

CHAPTER QUESTIONS

1.Define the terms public health, prevention, and epidemiology.

2.What are some of the critical public health issues facing our society?

3. -How has the field of public health in American changed since the 18th

century?

4. -How does public health differ from the practice of medicine in the United

States?

5.What role can pharmacy play in public health initiatives in America?

HISTORICAL PERSPECTIVE

Concepts and Definitions

The development of public health and health care delivery systems dates back to 18th century Europe and late 19th century America. Historically, public health has been an intricate combination of the sanitation, environmental, and medical sciences. As bacteriologic and immunologic advances were made and used to control communicable diseases, the concept of disease prevention was incorporated into public health. Eventually, public health evolved into an interdisciplinary agglomeration of (public or community) health sciences that now incorporates elements from the social, political, environmental, and behavioral health sciences in a number of specific functions that may be summarized as health promotion, disease prevention, and disease intervention activities in human populations (Hanlon and Pickett, 1984).

Public health has been defined in a variety of ways, but definitions tend to include efforts to promote healthy lifestyles through health promotion and health education initiatives and to prevent disease. In 1923, C.E.A. Winslow (1923) defined public health as preventing disease, prolonging life, promoting health through environmental efforts (including sanitation measures), controlling communicable diseases, advocating health education through personal hygiene, organizing medical and nursing services for early diagnosis and preventive treatment of disease, and ensuring health as a right of every citizen. Rosen (1993) added that:

Throughout human history, the major problems of health that men have faced have been concerned with community life, for instance, the control of transmissible disease, the control and improvement of the physical environment (sanitation), the provision of water and food of good quality and in sufficient supply, the provision of medical care, and the relief of disability and destitution. (p. 1) In a major report on the status of public health in America, the Institute of Medicine’s The Future of Public Health (Institute of Medicine, 1988) defined the mission of public health as “the fulfillment of society’s interest in assuring the conditions in which people can be healthy” (p. 40). Thus, the focus on community and social group responses to health promotion and disease prevention are central components to the definition of public health.

Prevention

The traditional approach to disease prevention has included the primary-secondary-tertiary model in public health. Primary prevention (often operationalized in health promotion activities) refers to the avoidance of disease occurrence as well as actions taken before disease onset. Examples include immunizations, water fluoridation, and prospective medication review for potential negative interactions. Secondary prevention refers to the early diagnosis (detection) and prompt treatment of disease and the avoidance of disability. Examples of secondary preventive efforts include hypertension and cholesterol screening, programs that encourage self-assessment for cancers, and pharmacist review of drug use in nursing homes. Tertiary prevention refers to the limitation or reduction of disability, when disease has already occurred, through rehabilitation designed to encourage recovery and prevent further problems. Examples of tertiary preventive initiatives include cardiac rehabilitation programs and occupational therapy for individuals with a variety of physical disabilities.

Epidemiology

Another way to examine public health is from a more epidemiological approach. The foundation of public health lies in an understanding of the principles and methods of epidemiology, defined as the study of the factors that determine the frequency, distribution, and etiology of disease in human populations. Whereas human populations are the basic focus of study, epidemiology examines the natural history of disease in populations through the epidemiologic triangle, consisting of three components: 1) the host; 2) the environment; and the 3) agent. Whereas the meaning of “environment” is familiar to us, the notion of host usually refers to the entity (often the individual) that is affected by the agent, which might be biological (insects and bacteria), chemical (gases and dusts), nutrient (fats and calories), or physical (radiation or humidity). This interaction between the host, environment, and agent determines the relative health or disease of a population.

The susceptibility or resistance of the human host to a disease agent is influenced by many factors, including population characteristics, genetics, and culture. The environment (physical, biologic, social, or economic) can assist or suppress the disease process. Most disease agents are biological, but may be physical, chemical, or nutrient. The presence or absence of these agents can cause disease. For example, designing a program against smoking would include the host (antismoking education, smoking cessation programs), the environment (no-smoking buildings, laws prohibiting minors from purchasing cigarettes), and the agent (low-tar cigarettes, nicotine patches). The value of this approach is found in strategies to target the environment and agent in addition to those efforts focused on populations. In the case study found at the beginning of the chapter, the committee might choose to include efforts to alter an environment that supports unprotected sex and to neutralize the agent by providing bleach to injection drug users who would sterilize needles if they choose to reuse them (CDC, 2003).

Space limitations do not permit a comprehensive list of key definitions and concepts in public health, prevention, and epidemiology. See Detels et al. ( 2002), Last et al. ( 2000), Rothman et al. (1998), Mausner and Kramer ( 1998), and Raczynski et al. (1999).

CHANGING HEALTH PRIORITIES

Acute Vs. Chronic Diseases

The nature of public health problems in the United States has changed over the past 200 years. Chronic diseases have superseded acute illnesses. Local public health issues like clean air, drinkable water, waste disposal have become national if not global in scope rather than specific to single countries or selected populations. Historically, these changes in health priorities illustrate the growth and progress of scientific knowledge in the etiology and control of disease in populations. Further, they illustrate the gradual acceptance of health promotion and disease intervention as a public responsibility in the United States. Finally, the development of public health practice in America also demonstrates that a number of public health issues and problems remain unresolved.

In the early days of health care in the United States, acute problems such as influenza, pneumonia, tuberculosis, and gastroenteritis were the primary causes of death (Cockerham, 2004). Much of the improvement in the nation’s health in the 1800s was attributable to improved sanitation and personal hygiene, better housing, and an increase in the availability of nutritious foods. These changes led to improvements in the nation’s health before the development of medications to effectively treat the diseases that were already in decline.

The late 1800s brought significant advances in bacteriology, including bacteriologic agents for contagious diseases such as tuberculosis, yellow fever, and diphtheria. Immunization and water purification initiatives were found effective in both disease prevention and disease control. Local and state governments established health departments as well as health laboratories to control contagious diseases. In addition, states established public institutions (then called “asylums”) for individuals with mental disorders. It was not until the early 1900s and the passage of the Food and Drug Act that the federal government undertook a more active role in establishing national health programs and assisted states in their efforts with specific diseases (Institute of Medicine, 1988; see Chapter 1).

Today, chronic illnesses like as cardiovascular disease, cancer, and stroke are the leading causes of death in the United States. This has expanded the focus of public health to include both the prevention of acute illnesses and the minimization of the effects of chronic diseases. This includes efforts in primary, secondary, and tertiary prevention. Nevertheless, the effectiveness or outcomes of these programs are often measured over decades rather than months or years. The shift in health promotion and disease intervention activities to a focus on chronic rather than acute illnesses has been complicated by new public health challenges that have developed alongside new medical technologic advances. For example, more than 42 million people worldwide were living with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/ AIDS) at the end of 2002 (Report on the Global HIV/AIDS Epidemic, 2002).

In the United States, an estimated 650,000 to 900,000 people are HIV positive (Healthy People 2010: Objectives for Improving Health, 2000). The majority of new cases of HIV infection are transmitted through sexual behavior, and approximately one half of all new cases of HIV infection are among people aged 25 years and younger. Black and Hispanic Americans have AIDS rates considerably higher than rates among Whites. The percentage of women with AIDS has increased steadily. In addition, the proportion of individuals infected heterosexually also has increased, having surpassed the percentage infected through drug injection.

HIV/AIDS

HIV/AIDS is not only an epidemic in the United States; it is a pandemic, affecting the health of populations throughout the world. Not only has profound suffering existed among individuals and their families from HIV/AIDS, but also HIV/AIDS will have a profound impact on future rates of infant, child, and maternal mortality; life expectancy; and economic growth (Report on the Global HIV/AIDS Epidemic, 2002).

Today and in the foreseeable future, the global disease burden needs to be considered in addition to the public health concerns of the community, region, and nation. Although we may think of international public health concerns in the context of communicable diseases such as HIV or ebola, the world population is living longer and is increasingly urbanized and challenged by poverty. The primary focus of future prevention and early intervention initiatives will include health, nutritional education and support, and control of infectious diseases. Adding to the disease burden of heart disease, cancer, and stroke, our worldwide public health concerns will include depression, alcohol abuse, tobacco use, and the problems associated with the health of an aging population (Giorgianni, 2000).

Individual vs. Population Perspectives of Health

Historically, medical care training focuses on the treatment of illness in the individual. Physicians and nurses are trained to curb the pain and suffering of a particular patient. Pharmacists are taught to provide appropriate medications for individual patients. Each health care professional focuses on the needs of an individual patient.

Public health, however, pursues a population-based, multidisciplinary approach to the treatment of diseases in specific at-risk populations. Disease prevention, morbidity reduction, and increased longevity do benefit individuals; nevertheless, public health professionals examine problems, issues, and diseases from a population-based perspective. For example, a smoking cessation program for a county school system, the reduction of morbidity from automobile accidents in newly licensed automobile drivers (adolescents between the ages of 16 and 18), or the increased longevity of a state’s older (ages 65–70) population through exercise programs are designed for targeted groups of at-risk populations and communities rather than the individual. Stephen Smith, MD, the first president of the American Public Health Association, illustrated this population-based perspective in his approach to a typhus outbreak in the mid-1800s (Nation’s Health, 1997). When Smith noticed that more than 100 victims of typhus fever lived in the same tenement, he found their building in disrepair, a basement filled with sewage, and tenants crowded into the rooms of the building. Smith pleaded with the landlord to improve the living conditions and encouraged the establishment of a citywide public health board that eventually became the New York Metropolitan Board of Health. In the spirit of public health, Smith’s efforts focused on the living conditions of an entire group of people rather than addressing the health needs of one individual at a time.

CHANGING HEALTH ROLES

Managed Care

The public health perspective becomes even more critical as society experiences a metamorphosis in the organizational structure and functioning of health care delivery. Health care delivery systems in the United States continue to be in a tumultuous state, with ever-increasing “industry” growth, diversification, consolidation, and service integration. In recent years, the continual flux in supply and demand for health services has encouraged the development of a wide variety of managed care organizations (MCOs) that finance and deliver health and specialty (e.g., behavioral) health services to specific (usually employed) populations. In recent years, state Medicaid plans and the federal Medicare programs have experienced a rapid growth of individuals enrolled in MCOs. Increasingly, these programs have used the creation of purchasing alliances (health service agencies that form a purchasing coalition) between public agencies and private MCOs and/or private specialty MCOs. For example, between 1994 and 2000, the Medicare enrollment in managed care rose from 7.9% to 17.8%, whereas between 1994 and 2000, managed care enrollment for Medicaid enrollees increased from approximately 40% to 56% ( National Center for Health Statistics, 2003).

Managed care originated in the 1920s in California with the development of a prepaid group practice called the Kaiser Permanente Medical Care Program, in which a variety of health and behavioral health services was offered to a defined group of subscribers based upon a monthly capitation rate. The concept of a prepaid group practice included opportunities to reduce costs through the prevention of disease (e.g., annual health check-ups and immunization for children) and promotion of health and behavioral health services.

The first major growth cycle for MCOs in the United States occurred between the early 20th century and the late 1960s with the growth in the number of prepaid group practice plans across the United States. The second major growth cycle for MCOs occurred in the early 1970s with the growth of the Individual or Independent Practice Associations (IPAs) model of health maintenance organizations (HMOs). The 1970s also marked the emergence of HMOs. IPAs were often more flexible than group or staff HMOs from the consumer perspective because consumers had considerably more choice in selecting their physician in an IPA-model HMO. The rise in popularity of for-profit HMOs occurred in the 1980s during the third major growth cycle of managed health care. During this growth cycle, the term “managed care” collectively included all types and organizational models of HMOs, point-of-service plans, and preferred provider organizations.