Cardiovascular Disease in Middle Aged Individuals in a Worksite Setting

Cardio-vascular disease (CVD) is the leading cause of death and leads the statistics for emergency room (ER) cases. This literature review combines two primary causative agents in CVD: (1) Stress in the workplace, and (2) Middle Age. This review will explore one of the key reasons why the harmful ramifications of stress and middle age can be nullified or, at least, reduced -- through physical activity and exercise.

Job stress is defined as harmful physical and emotional responses to job requirements that do not match the abilities, resources, or needs of the worker. Occupational stress is a perceived imbalance between occupational demands and the individual's ability to perform when the consequences of failure are significant (Brehm, 2002) This makes the entire concept of job stress a very personal and psychological matter -- whenever perceptions play an important role. Contemporary magazines like Newsweek, Time, and U.S. News and World Report have run features and cover stories on stress in the workplace and its effect on the average worker.

Work plays a powerful role in people's lives. It exerts an important influence on their well-being. Paid work (in some form since the beginning of time) has occupied an increasing proportion of most people's lives. While employment is challenging for most, it can also be a stressful. As work makes more and more demands on time and energy, individuals are increasingly exposed to both the positive also negative aspects of employment. It is essential to recognize three concepts:

Stress is an interaction between individuals and any source of demand (stressor) within their environment.

A stressor is the object or event that the individual perceives to be disruptive.

Stress results from the perception that the demands exceed one's capacity to cope. The interpretation or appraisal of stress is considered an intermediate step in the relationship between a given stressor and the individual's response to it.

Research has identified many organizational factors contributing to increased stress levels. They range from job insecurity, the vagaries of shift-work and long work hours, physical hazards to interpersonal conflicts with coworkers or supervisors. Reciprocally, elevated stress levels in an organization are associated with increased turnover, absenteeism, sickness, reduced productivity, and low morale. At a personal level, work stressors are related to depression, anxiety, general mental distress symptoms, heart disease, ulcers, and chronic pain. (Sauter and Hurrell, 1999) Any exploration of the relationship between work conditions and personal health must account for sex, age, race, income, education, marital and parental status, personality, and coping methods.

Lack of control over work, the work place, and employment status have been identified both as sources of stress and as a critical health risk for some workers. Employees who are unable to exert control over their lives at work are more likely to experience work stress and are therefore more likely to have impaired health. Studies have found that heavy job demand, and low control, or decreased decision latitude lead to job dissatisfaction, mental strain, and cardiovascular disease. (Israel et al., 1989). Similarly, the researchers concluded that the ability to control or influence work factors (e.g., speed and pacing of production) is linked to incidence of cardiovascular disease as well as to psychosomatic disorders, job dissatisfaction, and depression. Later in this review, reference will be made to an intervention that specifically addresses depression and cardiovascular disease. This depression finds a direct link to job stress.

Assuming that one of the drawbacks of emotional stress from job related problems was CVD, Lazarus (Lazarus, 1991) proposed an intervention with three primary strategies for reducing work-related stress:

Alter the working conditions so that they are less stressful or more conducive to effective coping. This works for large numbers of workers working under severe conditions. E.g., altering physical annoyances such as noise levels, or changing organizational decision-making processes to include employees.

Teaching employees better coping strategies. Intervention strategies could include individual counseling services for employees, Employee Assistance Programs, or specialized stress management programs. (Long, 1989)

Identify the stressful relationship between the individual or group and the work setting. Intervention strategies in these cases would include changing worker assignments to produce a better person-environment fit.

Personal behavior and habits also greatly impact the stress patterns that people experience. What may be stressful and challenging for one person, may be a motivator for another. Such workplace characteristics make it very difficult to set baselines for job-stress. (Gilpin and Gilpin, 2000) Individuals that maintain a good balance between their personal lives and their work, and those that have good social interactions with friends and family, tend to be less affected by work stress. Employees who also have good and healthy interactions with their co-workers also have better control over the extent that they allow work to affect them. An office environment which fosters honest and open interaction between the management and the worker helps workers relate to their jobs better. It improves their esteem about their work and their role in the organization.

They reported a feeling of being burned out. (Bond, Galinsky and Swanberg., 1998)

The center for disease control (CDC) conducted a study of heart disease and job stress. It found that having increased job control can reduce job stress, was associated with lower incidence of ischemic heart disease. It found no relationship between non-rotating shift work and the risk of heart disease. The 1996 benchmark report Physical Activity and Health: A Report of the Surgeon General brings together findings from decades of research. A major conclusion is that regular physical activity reduces the risk for cardiovascular disease. (CDC.gov, 1996)

Heart attacks and stroke -- the principal "presentations" of cardiovascular disease -- are, respectively, the first and third leading causes of death in the United States. They account for 40% of all deaths. About 950,000 Americans die of heart disease or stroke each year, which amounts to one death every 33 seconds. CVD related symptoms primarily kill the older people. Besides the mortality, consider the morbidity: While 61 million Americans (almost one-fourth of the population) live with the effects of stroke or heart disease; it is also the leading cause of disability in working adults. Six million hospitalizations occur due to CVD and there are 4.5 million survivors of stroke. These ominous findings have far reaching consequences. (AHA.org, Aha Statistics, 2003)

Several years of research have shown that the personal, health and economic consequences can be significantly minimized by employing simple life affirming attitudes: healthier lifestyles, increasing early detection and intervention, e.g. physical activity and enhanced lifestyle. Research done during the 1980s shows that community interventions that change our environment (places where we work, play, learn, or live) are particularly effective in reducing heart disease and stroke throughout the entire community. (ICIHEALTH.org, 2003)

In the U.S.A., New York has led the way in promoting heart healthy policies and environments through the New York Healthy Heart. In 1997, Gov. George Pataki earmarked 4.1 billion dollars to support this effort. The results have been spectacular -- work sites increased their support for heart health by 65%; their programs included more low-fat food choices, smoke-free workplace policies, physical activity breaks, and safer stairwells.

The fact that heart diseases are directly related to work stress is emphasized by knowledge of statistics of developed, industrialized nations. In North America and Western Europe, CVD still represents a significant public health problem - indeed, a pandemic. In the former Soviet Union and other eastern European countries, CVD morbidity and mortality have increased dramatically over the last 30 years (Wrzesniewski et al., 2000). The dominant focus of research and intervention in the medical community has been on individual traits, especially genetic susceptibility and risky behaviors, such as: smoking, over-eating, sedentary lifestyle.

The underpinnings of this explanation of the CVD epidemic lie in the development of powerful engineering models. CVD could be characterized as a disturbance in hydraulic (hemodynamic) and electrical (electrophysiologic) function (Braunwald, 1997). In addition to the biological and anatomical factors, a closer look at the overall public health impact of this traditional medical approach to CVD is in order. Although cardiovascular disease usually becomes evident in middle or older age, progressive harmful conditions (e.g., atherosclerosis) leading to such disease begin in childhood. These underscore the need for developing healthy lifestyles (among them physical activity) as a preventive method. "If you think being physically active at work is helping your heart, think again if you also have workplace stress," proclaimed James H. Dwyer, Ph.D., a professor at the Keck School of Medicine at the University of Southern California, Los Angeles.

Depression is highly prevalent among people with cardiovascular disease (CVD). It has been estimated that anywhere between 20% and 50% of the CVD population suffers from depression. (Carney et al., 1988; Zeigelstein et al., 2000)

Researchers at Stanford (Taylor, Cooke and Roth, 2000) proposed a comprehensive study of seventy nonsmoking men and women, age 55 or greater, at high risk for coronary artery disease -- but who were depressed. Besides medication and the usual care, they proposed a "cognitive-behavioral" intervention. The basic intervention will be cognitive-behavioral therapy for depression. Cognitive therapy would be aimed at symptom removal by identification and correction of the patient's distorted, negatively biased, moment-to-moment. This study is important because it provides an overview of the contemporary modalities that are available. The reference provides a comprehensive review of the methods to be used in their study.

The researchers proposed using The Subjective Index of Physical and Social Outcome (SIPSO) method in evaluating the results of the intervention. SIPSO is a brief self-complete measure which addresses both quantitative and qualitative aspects of activities and interaction that is reliable and valid. SIPSO emphasizes perception of the patient and includes assessment of the quality of activities and interaction. (Trigg, Wood and Langton, 1999) major study at Cornell University was undertaken to study the biological mechanisms associated with job strain on blood pressure and consequently on CVD. (JOB-STRESS-NETWORK, 2003) Several tests were carried out: To find out the levels of catecholamines and cortisol in urine, and the second was to use an ultrasound procedure to discern the extent of atherosclerosis from the thickness of the carotid artery -- greater thickness would mean greater plaque build up and therefore a more advanced progress of the disease. In addition to studying the affects on blood pressure, means by which job strain might affect CVD are due to an increase in the mass of the heart's left ventricle (LVMI), mechanisms such as coagulation, and the precipitation of myocardial infarction or arrhythmias among vulnerable persons with underlying heart disease. Results from the Cornell worksite study indicate a relationship of job strain to: hypertension (defined from casual blood pressure readings taken on two separate occasions), ambulatory blood pressure at work, home, and sleep, enlargement of the heart, and three-year changes in ambulatory blood pressure.

While it was determined that physical activity was generally protective of CVD, and overall physical activity at work (self-reported) was controlled for in many of the job strain-CVD studies (Ivancevich and Matteson, 1988).

In order to measure the progress of CVD, the following tools are key:

Blood pressure: Each time the heart beats, it pumps blood into the arteries, resulting in the highest blood pressure as the heart contracts. Two numbers are recorded when measuring blood pressure. The higher number, or systolic pressure, refers to the pressure inside the artery when the heart contracts and pumps blood through the body. The lower number, or diastolic pressure, refers to the pressure inside the artery when the heart is at rest and is filling with blood. Both the systolic and diastolic pressures are recorded as "mm Hg" (millimeters of mercury). The numbers: 140 mm Hg or greater systolic pressure and 90 mm Hg or greater diastolic pressure

High blood pressure can occur in anyone, but is particularly prevalent in persons with diabetes gout, or kidney disease. African-Americans in their early to middle adult years are particularly prone; men more than women; more than half of all Americans age 65 and older have high blood pressure, high blood pressure has been to shown to be an inherited trait; obese people, smokers and heavy drinkers are also probe to hypertension.

Pulse Rate: is a measurement of the heart rate, or the number of times the heart beats per minute. As the heart pushes blood through the arteries, the arteries expand and contract with the flow of the blood. Taking a pulse not only measures the heart rate, but also can indicate heart rhythm and strength of the pulse. The normal pulse for healthy adults ranges from 60 to 100 beats per minute. The pulse rate may fluctuate and increase with exercise, illness, injury, and emotions. Girls ages 12 and older and women, in general, tend to have faster heart rates than do boys and men. Athletes, such as runners, who do a lot of cardiovascular conditioning, may have heart rates in the 40's and experience no problems.

Respiration rate: is the number of breaths a person takes per minute. The rate is usually measured when a person is at rest and simply involves counting the number of breaths for one minute by counting how many times the chest rises. Respiration rates may increase with illness.

Normal respiration rates for an adult person at rest range from 15 to 20 breaths per minute. Respiration rates over 25 breaths per minute or under 12 breaths per minute (when at rest) may be considered abnormal.

Cardiac Mechanics: is focused on understanding how individual heart-muscle cells contribute to the contractile function of the complete heart, both in healthy and in pathological conditions. We are particularly interested in the adaptation of the heart muscle to changes in mechanical load, for instance induced by cardiac arrest or pacemakers. Functional MRI (Magnetic Resonance Imaging) techniques are developed and applied to assess pathology in electrically conductive and contractile pathologies.

Hemodynamics: Factors such as, local pressure, velocity, wall shear stress and wall deformation play a key role in the genesis and development of atherosclerotic disease and are crucial for the well-functioning of the heart and its natural or artificial valves. With the improvement of radiographic, ultrasound, MRI and intravascular techniques, factors like blood flow velocity, blood pressure and vessel wall motion are used in diagnosing the stage of cardiovascular diseases. Hemodynamical models help to understand diagnostic measurements and can predict the impact of clinical intervention technique. Balloon angioplasty, stents or vascular prosthesis implantation and medication will become increasingly important in future clinical practice.

Cardiovascular diseases are the most common cause of death and disability in the United States. Recent research in this area has expanded our understanding of the basic elements of cardiovascular system including development, anatomy, pharmacology, and control. Although great strides have been made in the approaches to manipulate cardiovascular function in the treatment of diseases we are on the threshold of a new era in cardiovascular research. Molecular and genetic approaches will allow us to not only study more closely the cellular function of elements of the cardiovascular system but also to provide new avenues for treatment of diseases.

Atherosclerosis is a general term for thickening or hardening of the arteries with plaque. Plaque is made up of deposits of fatty substances, cholesterol, cellular waste products, calcium, and fibrin, and can develop in medium or large arteries. The artery wall becomes thickened and looses its elasticity. Certain risk factors may be associated with atherosclerosis: elevated cholesterol and triglyceride levels, high blood pressure, smoking, diabetes mellitus, obesity and physical inactivity. Atherosclerosis is diagnosed by several modes. An angiogram or Doppler sonography and blood pressure comparison (measuring pressure in the ankles help determine if blood flow is restricted. A MUGA/radionuclide angiography is a nuclear scan to see how the heart wall moves and how much blood is expelled with each heartbeat while the patient is at rest. A thallium/myocardial perfusion scan, which is also a nuclear scan given while the patient is at rest or after exercise that may reveal areas of the heart muscle that are not getting enough blood.

One of the key preventive measures of heart diseases is regular exercise. An intervention may involve the design of activities in the workplace that enable workers to relieve stress by physical activity. Case records indicate that coronary heart disease strikes most commonly the persons of sedentary occupation. Regular exercise preferably a little each day rather than large amounts half a day per week, keeps the blood vessels in good tone and helps the heart to maintain its margin of safety and serves to flush out detrimental chemical substances which damage the body's tissues. A small period of exercise each day also breaks the spell of the damaging nervous pressure. There are important considerations while designing an exercise regimen. Even low-to-moderate, mundane intensity activities for as little as 30 minutes a day can be beneficial. These activities may include pleasure walking, climbing stairs, gardening, yard work, moderate-to-heavy housework, dancing and home exercise. (Hunt, Donato and Crespo, 1999)

More vigorous aerobic activities, done three or four times a week for 30 to 60 minutes, are best for improving the fitness of the heart and lungs. Regular, aerobic physical activity increases a person's capacity for exercise and plays a role in prevention of cardiovascular diseases. Aerobic exercise also helps to lower blood pressure. Examples of vigorous exercise may include brisk walking, running, swimming, cycling, roller-skating and jumping rope. One cannot emphasize the benefits of physical activity enough. The advantages are: an improved blood circulation throughout the body, weight control, better blood cholesterol levels, regulation of blood pressure, increased energy levels, stress relief, better sleeping patterns, improved self-image, counters anxiety and depression and increased muscle strength.

A daily exercise program can provide a way to share an activity with family and friends, while helping establish good heart-healthy habits. For older people, daily physical activity helps to delay or prevent chronic illnesses and diseases associated with aging, and maintain quality of life and independence longer.

An intervention in support of an exercise program in the work place would involve pre-evaluation of the workers' current medical conditions. Factors to be taken into account are, chest pain or pain in the neck and/or arm, shortness of breath, a pre-diagnosed heart condition, joint and/or bone problems, currently taking cardiac and/or blood pressure medications, previous level or duration of general physical inactivity and dizziness. Stress tests and blood pressure monitoring are the best evaluators of fitness level. As are a monitoring of blood pressure.

An ideal programs and services directed at CVD prevention and health promotion are tailored to meet the needs of the worksite would include the following (guidelines provided by Heart Check America (HeartCheckAmerica.com, 2003)):

Heart Check: This would include a thorough evaluation of an individual's lifestyle, plus a measurement of blood cholesterol, blood pressure and Body Mass Index (BMI). A personalized report and counseling would be provided to each participant. A workplace summary of group statistics and health enhancement interests is provided to employers. If possible one might even include comprehensive lifestyle and food frequency evaluations, plus measurement of total cholesterol, HDL-cholesterol, LDL-cholesterol, Triglycerides. In addition, the work place might arrange seminars and lectures followed by group discussions that would emphasize cardiac risk factors and recommendations for decreasing the risk of coronary heart disease. Examples of topics for discussion would be tailored to the work environment and the interests of employers/employees: "Stress in the Workplace," "Heart Healthy Eating," "Weight Management," "Quit Smoking" and "Physical Fitness."

Fitness Profile: This profile would results of a complete a standardized fitness test (which evaluates aerobic capacity, muscular strength and endurance, flexibility, and body composition). This fitness report and nutrition profile would be to each employee.

Stress Profile: A Stress Profile provides participants with a complete evaluation of work-related and personal stress, and helps identify coping resources. Personalized stress management plans are provided to employees and the employer is provided with a statistical profile of stresses in the workplace.

Executive Profile: includes a thorough medical history and evaluation completed by a physician, a graded exercise test with complete ECG monitoring and interpretation, a nutrition and stress profile, and a full blood lipid screening. A personalized eating, activity and stress management plan is included, along with one-to-one counseling.

Nutrition Analysis: in this program, participants are asked to complete a food frequency intake history, which is then analyzed. Each participant is then given a nutrition profile, including recommendations for change. A group debriefing is conducted by a professional Dietitian and individual counselling sessions would be arranged.

Lifestyle Workshops: would focus on areas such as nutrition and diet, ills of smoking, exercise, stress management, and heart disease risk reduction. The workshop would be held, for 25 to 40 employees, over a 4-6-week period at the employer's workplace.

Preventive Stress Management: works to help participants identify sources of personal and workplace stress. As part of the program, individuals would learn to evaluate and develop coping resources, and alter some of the factors which make them vulnerable to stress. This program would be designed for a small group (8-12 employees). Such a session might be moderated by a Certified Clinical Psychologist.

Personal Lifestyle Management Counselling: would ideally be available for individuals referred by their physician. Participants would meet with a professional health educator, bi-weekly over a 12-week period. During their meetings, the health educator would help them to develop individualized dietary, physical activity, and behavior change plans. A comprehensive health, lifestyle, fitness, nutrition, stress, and behavioral assessment is completed before and after the intervention period. Physician referral is required.