Antiplatelet Treatment Reduces All-Cause Mortality in COPD Patients: A Systematic Review and Meta-Analysis

Figures & data

Figure 1. Outline of search strategy. n = number.

Table 1. Baseline data and cardiovascular risk factors of study population.

				Age					Beta-	ACE-inhibitors		Mean
	Study	Pts	Female	(years)	Diabetes	Hypertension	CVD	CVD	blockers	or ARB	Statins	follow-up
References	design	(n)	(%)	mean	(n, %)	(n, %)	(n, %)	definition	(n, %)	(n, %)	(n, %)	length
Soyseth et al. (2007)	R	854	52%	71	–	179 (21)	243 (28)	IHD	111 (13)	179 (21)	736 (86)	1.9 years
Short et al. (2011)	R	5977	49%	69	855 (14)	–	2878 (48)	Hospital admission for IHD, HF, PVD	796 (13)	–	–	4 years
Ekstrom et al. (2012)	P	2249	59%	75	291(13)	–	1494 (66)	At least one of hypertension, HF, IHD, PVD, CVA	829 (37)	763 (34)	431 (19)	1 years
Harrison et al. (2014)	P	1343	51%	72 *	203(15)	–	377 (28) 70 (5) 188 (14)	Prior MI Prior surgical CR Stable angina	228 (17)	666 (50)	566 (42)	1 year
Campo et al. (2015)	R	694	47%	77	172(25)	376 (54)	235 (34)	IHD	203 (29)	350 (50)	441 (64)	1.9 years

Pts: patients. n: number. R: retrospective. P: prospective. CVD: cardiovascular disease. ACE: angiotensin converting enzyme. ARB: angiotensing II receptor blocker. IHD: ischemic heart disease. HF: heart failure. PVD: peripheral vascular disease. CVA: cerebrovascular accident. MI: myocardial infarction. CR: coronary revascularization. *: median.

Table 2. Main features regarding design and COPD diagnosis criteria.

References	Pts receiving antiplatelets (n, %)	Sources of data	COPD diagnosis criteria	Pts with AECOPD at the time of the enrolment	AECOPD diagnosis criteria	FEV1	Adjusting factors in univariate and multivariate analysis
Soyseth et al. (2007)	224 (26)	Medical reports	Previous clinical diagnosis, spirometry available in 72% of cases.	Y	ICD codes for AECOPD, verified by a physician	Y	age, sex, DM, FEV1, smoking, IHD, CV drugs, RD, hypertension, HF, AF, TE, cancer.
Short et al. (2011)	—	Scottish morbidity records and General Register Office for Scotland using ICD codes.	Prior COPD diagnosis confirmed by spirometry	N	—	Y	age, sex, DM, FEV1, smoking, CV drugs, CV and respiratory hospital readmission, resting arterial O2 sat, deprivation index.
Ekstrom et al. (2012)	887 (39)	National Swedish patient register using ICD codes.	Prior COPD diagnosis confirmed by spirometry at the baseline	N	—	Y	age, sex, DM, FEV1, smoking, hospitalization, CV disease, CV drugs, RD, PaO2 and CO2 air, BMI, WHO performance status, anemia, renal failure.
Harrison et al. (2014)	713 (53)	Medical records and hospital records and morbidity database using ICD codes.	Prior COPD confirmed by spirometry in stable phase	Y	As reported in the EXODUS registry, a multicentre audit database	Y	age, sex, FEV1, smoking, IHD, LTOT, CV disease, platelet count, CV drugs, cancer, BMI, MRC dyspnoea score, oxygen therapy, acidosis, PaO2 and CO2, BAP65, long-term care.
Campo et al. (2015)	424 (61)	Programmazione e controllo di gestione, Statistica Sanitaria using ICD codes.	Prior COPD confirmed by spirometry	Y	Acute change of baseline dyspnea, caught, sputum production	N	age, sex, DM, hypertension, dyslipidemia, smoking, IHD history, WBC, Hb, PLT, fibrinogen, CRP, CV drugs, arterial blood gases, creatinine, troponin elevation.

Pts: patients. COPD: chronic obstructive pulmonary disease. AECOPD: acute exacerbation of COPD. FEV₁: forced expiratory volume 1 second. Y: yes. N: no. ICD: international classification of disease. DM: diabetes mellitus. IHD: ischemic heart disease. CV cardiovascular. RD: respiratory drugs. HF: heart failure. AF: atrial fibrillation. TE: thrombo-embolism. BMI: body mass index. WHO: world health organization. BNP: brain natriuretic peptide. LTOT: long-term oxygen therapy. WBC: white blood cells. Hb: haemoglobin. PLT: platelets. CRP: C-reactive protein.

Figure 2. Meta-analysis of studies testing the association between antiplatelet treatment and all-cause mortality in COPD patients. Data are displayed for each available study. Error bars represent 95% confidence intervals. SE: standard error. CI: confidence interval.

Figure 3. Funnel plot of standard error.

Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, Ioannidis JP, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration. BMJ 2009; 339:b2700.

 Google Scholar

DerSimonian R, Laird N. Meta-analysis in clinical trials. Control Clin Trial 1986; 7(3):177–188.

 PubMedGoogle Scholar

Campo G, Guastaroba P, Marzocchi A, Santarelli A, Varani E, Vignali L et al. Impact of COPD on long-term outcome after ST-segment elevation myocardial infarction receiving primary percutaneous coronary intervention. Chest 2013; 144(3):750–757.

 Google Scholar

Maclay JD, McAllister DA, Johnston S, Raftis J, McGuinnes C, Deans A, et al. Increased platelet activation in patients with stable and acute exacerbation of COPD. Thorax 2011; 66(6):769–774.

 Google Scholar

Short PM, Lipworth SI, Elder DH, Schembri S, Lipworth BJ. Effect of beta blockers in treatment of chronic obstructive pulmonary disease: a retrospective cohort study. BMJ 2011; 342:d2549.

 Google Scholar