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Particle Pollution and Your Patients' Health

Clinical Scenarios for Particle Pollution

Clinical Scenario 1

Mr. Richards is a man of 75 years with a history of hypertension, hyperlipidemia, diabetes, and atherosclerotic coronary artery disease. In spite of coronary artery bypass grafting, he still has residual flow-limiting coronary artery disease and stable angina. With therapeutic lifestyle changes and medications, Mr. Richards has achieved his goal for blood pressure, A1C, and serum lipids, and is generally free from angina except when doing very strenuous activity.

Mr. Richard's daily exercise routine includes walking in his neighborhood in the late afternoon. The initial part of his route takes him along a sidewalk adjacent to a busy road carrying heavy afternoon automobile, bus, and truck traffic. As he returns to his home, his route takes him up a steep hill. Most of the time, he can complete his walk in 60 minutes without shortness of breath or angina.

Occasionally, Mr. Richards experiences dyspnea with exertion as well as substernal chest pain and pressure when walking up the hill. He denies pleuritic chest pain, nausea, or diaphoresis. The discomfort quickly subsides when he stops walking. He has not felt the need to use sublingual nitroglycerin to relieve the chest pain. Of note is that he reports that his symptoms are more likely to occur when the air has been hazy for a few days. He is concerned that the intermittent chest pain is related to worsening of his coronary artery disease, and he seeks assistance from his family medicine physician.

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Clinical Scenario 2

Mrs. Smith, a 68-year-old woman, lives in a small valley along the coast that is susceptible to the rapid accumulation of air pollutants during temperature inversionsHelp inversion An atmospheric condition where a layer of cooler air is trapped near the ground by a layer of warmer air above. When the air cannot rise, pollution at the surface also is trapped and can accumulate, leading to higher concentrations of ozone and particle pollution. . She has a history of a dilated cardiomyopathy and the etiology is unknown. Comprehensive cardiovascular evaluation disclosed no evidence of coronary artery disease or familial history of cardiomyopathy. She has never been a smoker and has no documented parenchymal lung disease, hypertension, diabetes, or drug use. Her history has been characterized by intermittent exacerbations of heart failure with one hospitalization three months ago. Her clinical status is usually defined as New York Heart Association Class II and Stage C. Her medications include a long-acting beta-adrenergic receptor blocker, an ACE inhibitor, spironolactone, and a loop diuretic. She walks outdoors daily as tolerated, weighs herself daily, and adheres to her medication schedule and a low-salt diet.

Over several days, she noted that the air was hazy in association with a temperature inversion. Over the last few days, the AQIHelpAir Quality Index (AQI) A nationally uniform index for reporting and forecasting daily air quality. It is used to report on the four most common ambient air pollutants that are regulated under the Clean Air Act: ground-level ozone, particle pollution (PM10 and PM2.5), carbon monoxide (CO), and sulfur dioxide (SO2). The AQI focuses on health effects that may be experienced within a few hours or days after breathing polluted air. for her geographical area has reported an orange level—unhealthy for sensitive groups. She has taken precautions to limit her exposure to the smog by reducing her time outdoors and discontinuing her outdoor exercise. Yet she has noted the progressive onset of shortness of breath, a 3-pound weight gain over the last two days, an increase in orthopnea, and leg swelling. She denies paroxysmal dyspnea, palpitations and dizziness, or syncope.

On exam she appears to be volume overloaded with increased central pressures, bibasilar rales, and significant pre-tibial edema. An S3 gallop is present. While her immediate concern is a remedy for her worsening symptoms of heart failure, she asks you whether there is a relationship between the quality of the air and the onset of her symptoms.

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Clinical Scenario 3

Mr. Jones is a 57-year-old man with a five-year history of coronary artery disease, complicated by an anterior myocardial infarction three years earlier that has caused the left ventricular (LV) ejection fraction to decrease to 40 percent. Residual ischemia was treated with a drug-eluting stent to the mid-left anterior descending artery after a large diagonal and septal artery.

Approximately six months later, on a hot and hazy summer evening, Mr. Jones sustained an episode of ventricular fibrillation. A bystander witnessed the arrest and immediately initiated CPR. Subsequently, he was defibrillated by EMS personnel and recovered without complications. This event occurred despite his adherence to his medications, which included aspirin, a platelet P2Y12 receptor inhibitor, a statin, an ACE inhibitor, and a long-acting beta-adrenergic receptor blocker.

Repeat coronary angiography disclosed a patent LAD stent and no new obstructive lesions. Subsequently, an ICD was implanted. Over time, his LV ejection fraction has remained 35 to 40 percent without evidence of ischemia or aneurysmal dilation. Recently, a temperature inversion led to the accumulation of air pollutants with the appearance of a dense haze. He noted an increase in minor symptoms such as eye and throat irritation and intermittent cough. His breathing was not affected, but while walking to his mailbox he suddenly felt weak. As he started to sit, he received a therapeutic shock from the ICD. Subsequently, an interrogation of the device showed sustained and rapid ventricular tachycardia.

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Clinical Scenario 4

An older man, a patient of yours, comes to your office in early spring complaining of frequent cough with phlegm, which he has developed over the recent months. He stopped smoking 30 years ago. He casually mentions that he is at times short of breath when bringing firewood into the house, but "the cord of wood is almost gone by this time of year.” He also mentions that he has noticed his wife coughing more often than is usual, though otherwise she is doing fine. He is taking high blood pressure medication and occasionally over-the-counter pain relievers. 

You saw him in early fall for a routine annual check-up. At that time, he was doing well and, apart from controlled blood pressure and minor aches, had no major complaints. He has mild COPD not requiring medication. His spirometric parameters (FEV1, FEV1/FVC) were at the lower limit of normal for his age but FEF25-75 was reduced. On this visit, he has no fever, chest discomfort, or changes in bodily functions. However, his FEV1 is about 5 percent lower than it was when you saw him six months ago. A chest film shows mild hyperinflation but no masses or infiltrates. 

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Clinical Scenario 5

You have treated John for asthma since early childhood. He is skin-test positive for house dust mite antigen. He is now a sixth grader and comes to your office with his mother. You are a bit surprised by the visit, because his scheduled annual check-up is still a couple of months away. When inquiring why, you are told that he ran out of bronchodilator refills earlier than usual. His mother reports that during school days John is using his inhaled bronchodilator more frequently than before. On further questioning, she recalls that he has had a couple of nocturnal asthma attacks, which she controlled by “rescue” inhaled medication. John has not had any upper respiratory tract infection (URI) symptoms.

His mother mentions that since last September John has been attending a new middle school. She reports that he likes it very much; however, it is a bit noisy in the classroom because they are widening an interstate close to the school and the students can hear movement of heavy trucks and machinery going on all day long. This work has been going on for at least half a year. His medical history since you last saw him is otherwise unremarkable. The home environment has essentially remained unchanged, with no pets. He has a few high-pitched wheezes over the anterior chest on expiration.

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Clinical Scenario 6

Mrs. K. is a 35-year-old non-smoker who comes to your office because of seasonal allergy symptoms (rhinitis, conjunctivitis) that she cannot sufficiently control with the over-the-counter medication she has used in the past. She denies wheezing or chest tightness. Apart from her mild allergy to pollen, which has manifested during springtime over several years, her past medical history is not significant.

A thorough environmental history reveals that she lives in a neighborhood that was once rural, but has grown substantially over the last couple of years and has become a high-density residential area. She likes to jog around the neighborhood every afternoon when she returns from her work as a secretary in an insurance office. Nobody in her household smokes and she does not have any pets. She is not allergic to any food. After excluding all major risks factors, you decide that it is unnecessary to do any allergy or pulmonary function tests at this time. However, when you are taking her environmental history, she mentions that traffic in the neighborhood where she runs after work is much heavier than it used to be.

View the discussion for Clinical Scenario 6