Chronic Bronchitis and Emphysema.  Deaths from chronic obstructive bronchopulmonary diseases increased markedly between 1949 and 1959, and subsequent studies continue to show an upward trend. The frequency of chronic obstructive bronchopulmonary diseases has also risen rapidly, with these conditions now ranking second among the causes of disability in persons over age of 50 years. The death rate from chronic obstructive bronchopulmonary disease has increased from 2.1 per 100,000 population in 1949 to 12.9 in 1967. Chronic bronchitis and emphysema are the chronic bronchopulmonary diseases of greatest importance in the United States. Deaths primarily due to chronic bronchitis and emphysema in 1967 totaled 21,507 men and 3,885 women. The estimate of the death rate from chronic bronchitis and emphysema for 1969 is 14.3 per 100,000 populations. Numerous clinical studies have shown that cigarette smoking is more common among patients with chronic bronchitis and emphysema than among comparable patients in control groups set apart for study.

慢性支气管炎和肺气肿。在1949年至1959年间，死于慢性阻塞性支气管肺病明显增加，随后的研究持续呈现一种上升趋势。阻塞性支气管肺病的频率也迅速上升，现在这种情形在50岁以上人员残疾的原因中位列第二。阻塞性支气管肺病的死亡率从1949年的每10万人口2.1人增长到1967年的12.9人。在美国，慢性支气管炎和肺气肿是最主要的慢性支气管肺病。由于慢性支气管炎和肺气肿，1967年主要死亡的男性总数达21507人，女性为3885人。1969年患慢性气管炎和肺气肿的死亡率预计每10万人口为14.3人。许多临床研究表明，吸食卷烟在患有慢性支气管炎和肺气肿患者中相比分开进行研究的，可比较对比组中的患者更常见。

When human beings inhale cigarette smoke, the respiratory tract is subjected to fairly complete exposure to the minute particles and gases found in the smoke. When experimental animals are exposed to the irritant gases found in cigarette smoke, their airways receive damage that resembles the changes found in chronic bronchitis. Functional alteration, by cigarette smoke, of the cleansing mechanism of the upper and lower airways also has been documented extensively. Like several other agents, cigarette smoke can reduce or abolish the ability of the hair-like cilia to move back and forth. Changes in the goblet cells and mucous glands that produce the protective substance lining the airways have been found more commonly in cigarette smokers. Cigarette smoke also appears to affect the lining substance of the air sacs (alveoli) and to interfere with the stability of this portion of the lung tissue.

当人类吸入卷烟烟雾时，会发现呼吸道完全暴露在烟雾的微小颗粒和气体中。发现当实验动物暴露在卷烟烟雾刺激性的气体中时，它们的气道便受到损害，这类似于在慢性支气管炎中发现的变化。由于卷烟烟雾，也广泛记录了上呼吸道和下呼吸道清理机制的功能变化。像其它的一些介质一样，卷烟烟雾会减少或破坏像毛发一样的纤毛来回移动的能力。研究发现，杯状细胞和粘液腺中的变化产生了气道内衬的保护物质，在卷烟吸食者中更常见。卷烟烟雾似乎也会影响气囊（肺泡）的衬里物质，并干扰这部分肺组织的稳定性。

The prime defense mechanism of the lower respiratory tract is found in the alveolar phagocyte, a cell that ingests and transports harmful substances away from the delicate lung tissue. It is well documented that inhaled products of burning tobacco are ingested by alveolar phagocytes in man and experimental animals. In mice exposed to cigarette smoke over a two-year period, marked impairment of this clearance mechanism occurred, and the lung tissue became flooded with particles from the smoke. It has not been established whether such failure under stress of high-level, protracted exposure to cigarette smoke occurs in man.

在肺胞噬细胞中发现了下呼吸道的主要防御机制，一种吸收并运送有害物质，远离脆弱肺组织的细胞。这充分证明，燃烧的烟草吸入物是由人类和实验动物的肺胞噬细胞吸收的。在卷烟烟雾中暴露超过两年的小鼠，这种清理机制会出现明显损伤，而且肺组织充满了烟雾颗粒。目前还无法确定，这种在高压、长时间暴露在卷烟烟雾下的失效是否会在人身上出现。

The acute effects of cigarette smoking on lung function result in an increase in air flow resistance, uneven ventilation, and increased work in breathing. These effects are reversible after a person stops smoking. Chronic exposure to cigarette smoke results in a definite reduction in ventilation of the lung and interference with the body’s exchange of carbon dioxide for oxygen. In the young smoker who discontinues smoking, these changes disappear. It is not known, however, whether continued smoking for longer periods will make the functional impairments irreversible.

吸食卷烟对肺功能的急性影响会导致气流阻力增加，呼吸不均匀，以及增加吸吸负担。在人停止吸烟后，这些影响是可逆的。长期暴露在卷烟烟雾中会导致肺部供气明确减少，并干扰身体二氧化碳与氧气的交换。在戒烟的年轻吸烟者中，这些变化消失了。然而，尚不清楚，较长时期的持续吸烟是否会使功能损害不可逆转。

Alterations in human tissue occur as a result of cigarette smoking not only in the surface epithelium and mucous-producing cells and glands of the airways, but also in the lung tissue itself. Rupture of the air sacs, formation of fibrous tissue (fibrosis), and thickening of blood vessel walls are the pathological changes found in the lung tissue of cigarette smokers. The findings correlate closely with cigarette smoking habits; the greater and longer the exposure, the more severe the damage.

由于吸食卷烟，人体组织的变化不仅发生在表面上皮，气道中生成粘液的细胞和腺体，而且也出现在肺组织本身。气囊的破裂，纤维组织（纤维化）的形成，以及血管壁的增厚都是在卷烟吸食者肺组织中发现的病理变化。这些发现与吸食卷烟习惯息息相关；暴露的程度愈大，时间愈长，损害就愈严重。

Extensive studies based on the prevalence of specific signs and symptoms show a consistently more frequent occurrence of the manifestations of chronic bronchitis (cough, sputum, or the two combined) in cigarette smokers than in nonsmokers. Breathlessness, often a manifestation of emphysema, is associated with cigarette smoking in males. Thus, the clinical EXPRESSIONS associated with chronic bronchitis and emphysema is closely linked with cigarette smoking.

基于对特定体征和症状流行的广泛研究表明，出现慢性支气管炎（咳嗽、咳痰，或两者兼有）在卷烟吸食者中始终比不吸烟者更常见。呼吸急促，肺气肿常有的一种表现，与男性吸食卷烟有关。因此，慢性支气管炎和肺气肿的临床表现与吸食卷烟密切相关。

All seven prospective studies show a higher mortality rate for chronic bronchitis and emphysema among cigarette smokers than among nonsmokers. One of these studies placed the risk of dying from chronic bronchitis at four times higher among the cigarette smokers. The risk of dying from emphysema was 7.5 times greater for cigarette smokers in one study and 13 times greater in another. Taken together, the risk of dying from chronic bronchitis and emphysema is about five or six times greater among cigarette smokers than among nonsmokers.

所有七项前瞻性研究表明，卷烟吸食者的慢性支气管炎和肺气肿的死亡率要更高于不吸烟者。其中一项研究显示，在卷烟吸食者中，慢性支气管炎的死亡风险高于不吸烟者4倍。在一项研究中，卷烟吸食者的肺气肿死亡风险是不吸烟者的7.5倍，在另一项研究中是13倍。总的来说，在卷烟吸食者中慢性支气管炎和肺气肿的死亡风险比不吸烟者大约高出了5倍或6倍。

Experimental evidence shows that the lung may be damaged by noxious agents found either in tobacco smoke or air pollution. In Britain, the risk of developing disabling or fatal respiratory disease is obviously greater for those exposed to the noxious agents from cigarette smoke and air pollution than for those exposed to either alone. In the United States, cigarette smoking undoubtedly plays a much more important role than air pollutants in causing chronic bronchopulmonary conditions.

实验证据表明，肺部可能受到烟草烟雾或空气污染中发现的有毒物质损害。在英国，暴露在卷烟烟雾和空气污染有毒物质中的那些人，患致残或致命呼吸道疾病的风险明显高于单独暴露在一种有毒物质中的那些人。在美国，吸食卷烟比空气污染所导致的慢性支气管肺病无疑扮演了一个更重要的角色。

In summary, cigarette smoking is the most important cause of chronic obstructive bronchopulmonary disease in the United States. The smoking of cigarettes increases the risk of dying from chronic bronchitis and from pulmonary emphysema, and cessation of smoking reduces the symptoms and the risk of death from chronic bronchopulmonary disease.

总之，在美国，吸食卷烟是慢性支气管肺病最重要的原因。吸食卷烟增加了慢性支气管炎和肺气肿的死亡风险，而停止吸烟可减少慢性支气管肺病的症状和死亡风险。

Cardiovascular Diseases.  Coronary heart disease accounts for more than 500,000 deaths in the United States annually, or about 75% of the deaths caused by heart disease. Coronary heart disease produces death by reducing the blood supply to the heart muscle, causing a myocardial infarction, or “heart attack.”

心血管疾病。在美国，每年有超过50万人死于冠状动脉心脏病，约占由心脏病导致死亡人数的75%。冠状动脉心脏病通过减少对心肌的供血，引发心肌梗死，或“心脏病暴发”导致死亡。

Inhalation of tobacco smoke and nicotine administration produce such immediate cardiovascular responses as increase in heart rate, cardiac output, blood pressure, oxygen consumption by the heart, and arrhythmia formation. No one specific cardiovascular effect has been demonstrated that would explain the relationship between cigarette smoking and coronary heart disease or other cardiovascular diseases. The risk factor induced by cigarette smoking appears to operate independently of, although it may act jointly with, other risk factors (high serum cholesterol, high blood pressure, and physical inactivity) contributing to the development of coronary heart disease.

吸入烟草烟雾和摄入尼古丁会立刻产生诸如心率、心脏输出量、血压、心脏耗氧量上升，以及形成心律不齐这样的心血管反应。还没有一种特定心血管的影响能解释吸食卷烟与冠状动脉心脏病或其它心血管疾病之间的关系。尽管它可能会与其它风险因素（高血清胆固醇、高血压和身体缺乏运动）共同作用，导致冠心病的发生，但吸食卷烟所诱发的风险因素似乎独立于其它的风险因素。

Cigarette smoking has been shown in a number of epidemiologic studies to be a significant risk factor in males, and to a lesser extent in females, in contributing to the development of coronary heart disease and to the significantly greater mortality rates among cigarette smokers. Death rates due to coronary heart disease increase particularly during middle life with the amount smoked, and the cessation of cigarette smoking decreases the risk of death from coronary heart disease. The risk of coronary heart disease is appreciably less for smokers of pipes and cigars.

许多流行病学的研究表明，吸食卷烟已被证实是男性的一种重要风险因素，而女性相对较小，在吸食卷烟者中，会导致患冠心病和更高的死亡率。冠心病的死亡率随着吸烟量而增加，尤其是在中年时间，而停止吸食卷烟会减少冠状动脉心脏病的死亡风险。对于烟斗和雪茄的吸烟者来说，冠状动脉心脏病的风险明显更少。