HIV linked to higher chance of obstructive lung disease in smokers over 40.
Chronic obstructive pulmonary (lung) disease (COPD *) (Figure 1) affects as many as 1 in 10 people with HIV. (2) High rates of smoking and lung infection could contribute to development of COPD in HIV-positive people. Previous studies confirmed that COPD affects a higher proportion of people with HIV than without HIV. (3-5) But these studies relied on medical records or self-report to establish COPD. The studies did not directly test people for lung function.
Researchers in France conducted this study to see whether airway obstruction determined by standard spirometry breathing tests affects more smokers with HIV than without HIV.
How the study worked. HIV-positive study participants came from France's HIV CHEST study, which tested the value of chest tomography (an image-making scan) to detect lung cancer. Study participants were at least 40 years old, had a lowest-ever CD4 count below 350, and had a last CD4 count above 100. All study participants were heavy smokers: they smoked at least 20 pack-years. Twenty pack-years means, for example, smoking 2 packs daily for 10 years (2 x 10 = 20) or smoking 1 pack daily for 20 years (1 x 20 = 20). People smoked at the time of the study or quit in the past 3 years. No one had AIDS, an active cancer, or a lung infection in the last 2 months.
HIV-negative study participants came from the CONSTANCES cohort, an ongoing analysis of people between 18 and 69 years old throughout France. CONSTANCES members selected for this study also smoked at least 20 pack-years and smoked at the time of the study or within the past 3 years. For every 1 HIV-positive person, researchers randomly picked 2 HIV-negative CONSTANCES participants of the same sex and about the same age.
All study participants had spirometry tests of their breathing capacity. Researchers determined several standard breathing capacity measures: forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio. They used FEV1/FVC ratio as the main study outcome. The secondary outcome was FEV1/FCV ratio less than 0.70 and FEV1 less than 80%, which together offer an indicator of moderate to severe COPD.
The research team used accepted statistical methods to identify links between (1) FEV1/FVC ratio or (2) COPD and HIV status (positive versus negative), age, sex, amount of smoking, and other factors. This kind of analysis identifies individual factors linked to FEV1/FVC or COPD regardless of whatever other risk factors a person has.
What the study found. The study involved 352 smokers with HIV and 702 smokers without HIV. Median (midpoint) age of both groups stood at 50 years, and 17% of people in both groups were women. Median number of pack-years smoked was slightly higher in the HIV group (30 versus 28 pack-years). A lower proportion of people with HIV than without HIV quit smoking within the past 3 years (9% versus 33%). Among people with HIV, median CD4 count stood at 573, and 89% of these people had an undetectable viral load. Median lowest-ever CD4 count was 174, meaning more than half of the people with HIV once had a CD4 count below 200.
FEV1/FVC ratio was lower (worse) in people with HIV than without HIV (0.72 versus 0.77). And a higher proportion of the HIV group had obstructive lung disease indicated by spirometry test results (19% versus 9%).
The statistical analysis that identifies independent predictors of lower or higher FEV1/FCV found 6 such predictors, including infection with HIV:
Linked to lower (worse) FEV1/FVC:
* HIV infection
* Every 10 years older age
* Every 5 pack-years more smoking
* Hepatitis C virus (HCV) positive
Linked to higher (better) FEV1/FVC:
* Being a woman
* Every 1 point higher body mass index (a measure of weight)
A separate analysis identified 3 factors that independently raised odds of COPD, as defined in this study. This analysis linked HIV infection and every additional 10 years of age to about 75% higher odds of COPD (Figure 2). Every additional 5 pack-years of smoking raised the odds of COPD about 10% (Figure 2).
What the findings mean for you. This large, careful comparison of current and former smokers with or without HIV produced solid evidence that HIV itself--regardless of other risk factors--raises the odds of airway obstruction (COPD). A history of more smoking and older age also independently predicted COPD in this statistical analysis.
COPD is a serious ongoing lung disease that makes it difficult to breathe. (6-8) Unless treated, COPD gets worse over time. COPD is the fourth leading cause of death in the United States. (6)
Smoking is the major cause of COPD, but up to 25% of people with COPD never smoked. (6) Other causes and risk factors for COPD are older age, asthma, COPD in a close family member, and regular exposure to irritants including second-hand smoke, air pollution, chemicals, dust, and fumes. (6,9) A genetic disorder called alpha-1-antitrypsin deficiency may lead to COPD in a tiny proportion of people. (7) This study shows that in current or former smokers 40 years old or older, HIV infection also boosts chances of COPD, regardless of whatever other risk factors a person has.
People with HIV, especially smokers, should know the warning signals of COPD: shortness of breath (especially during physical activity), wheezing, chest tightness, continuing cough, and frequent lung infections. (7,8) If you notice any of these signals, you should talk to your HIV provider immediately, especially if you smoke. Health experts advise providers to check for COPD in all smokers 40 or older (9)--like the people in this study.
Because smoking poses a high risk of COPD, smokers with HIV should try hard to stop. Your HIV provider can prescribe medications or nicotine-replacement products that will help you stop smoking. An online program developed specifically for smokers with HIV has helped people quit. (See the link at reference 10 below.) Many people try and fail to stop smoking, then succeed. So keep trying.
(1.) Makinson A, Hayot M, Eymard-Duvernay S, et al. HIV is associated with airway obstruction: a matched controlled study. AIDS. 2018;32:227-232.
(2.) Bigna JJ, Kenne AM, Asangbeh SL, Sibetcheu AT. Prevalence of chronic obstructive pulmonary disease in the global population with HIV: a systematic review and meta-analysis. Lancet Global Health. 2018;6:e193-e202. http://dx.doi.org/10.1016/S2214-109X(17)30451-5
(3.) Crothers K, Butt AA, Gibert CL, Rodriguez-Barradas MC, Crystal S, Justice AC. Increased COPD among HIV-positive compared to HIV-negative veterans. Chest. 2006;130:1326-1333.
(4.) Crothers K, Huang L, Goulet JL, et al. HIV infection and risk for incident pulmonary diseases in the combination antiretroviral therapy era. Am J Respir Crit Care Med. 2010;183:388-395.
(5.) Madeddu G, Fois AG, Calia GM, et al. Chronic obstructive pulmonary disease: an emerging comorbidity in HIV-infected patients in the HAART era? Infection. 2012;41:347-353.
(6.) National Heart, Lung, and Blood Institute. COPD, also known as chronic obstructive pulmonary disease, emphysema. https://www.nhlbi.nih.gov/health-topics/copd
(7.) Mayo Clinic. COPD. https://www.mayoclinic.org/diseases- conditions/copd/symptoms-causes/syc-20353679
(8.) American Lung Association. Chronic obstructive pulmonary disease (COPD). http://www.lung.org/lung-healthand-diseases/lung-disease-lookup/copd/
(9.) Global Initiative for Chronic Obstructive Lung Disease. http://goldcopd.org/gold-2017-global-strategy-diagnosismanagement-prevention- copd/
(10.) PositivelySmokeFree. https://www.positivelysmokefree.com/
* Words in boldface are explained in the Technical Word List at the end of this issue.
Caption: Figure 1. Inflammation and obstruction of lung airways can lead to COPD, chronic obstructive pulmonary disease. (Illustration from Servier PowerPoint Image Bank, http://smart.servier.com/).
FIGURE 2. This study linked three factors to higher odds of chronic obstructive pulmonary disease (COPD): HIV infection, every additional 10 years of age, and every additional 5 pack-years of smoking. Factors tied to higher odds of CORD HIV 72% Older age 77% More smoking 11% Note: Table made from bar graph.
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|Title Annotation:||ARTICLE 2|
|Publication:||HIV Treatment: ALERTS!|
|Date:||May 1, 2018|
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