Impact of long-term doxycycline on lung function & exacerbations: A real-world open, prospective pilot observation on chronic obstructive pulmonary disease.

BACKGROUND & OBJECTIVES: Upregulation of matrix metalloproteinases (MMPs) is related to the pathogenesis of chronic obstructive pulmonary disease (COPD). We aimed at assessing the tolerability and impact of long-term use of MMP inhibitor doxycycline in COPD. METHODS: A cohort of COPD patients was randomized to continue a uniform COPD treatment with or without add-on long-term oral doxycycline. The lung exacerbations (spirometry), adverse events and health status (COPD Assessment Test score) were noted at 3, 6, 9 and 12 months of therapy. Measurement of the serum MMP-2, and 9 and high-sensitive C-reactive protein (hs-CRP) levels was done at the start of the study and at three months, whenever possible. RESULTS: There were 27, 19, 13 and 10 patients with add-on doxycycline group and 22, 19, 11 and 7 patients with COPD treatment alone at 3, 6, 9 and 12 months of treatment respectively. The improvement was obvious and mostly (at 6 and 12 months) significant (P >0.05) for lung function parameters [forced expiratory volume in one second (FEV1), FEV1/forced vital capacity (FVC) and forced expiratory flow at 25-75% of FVC (FEF25-75)] and universal for health status at all measurements, with an overall 26.69 per cent reduction in exacerbations. The analysis with the lung function changes in the available population with protocol violation also supported the same trend. The concomitant reduction in serum MMP-9 (P =0.01), MMP-2 (P =0.01) and hs-CRP (P =0.0001) levels (n=21) at three months was also significant. The adverse reactions with add-on doxycycline appeared acceptable. INTERPRETATION & CONCLUSIONS: Long-term doxycycline appears well tolerated and seems to improve lung function, health status and exacerbations in COPD. The claim needs further scientific validations.

A novel approach towards non-obstructive detection and classification of COPD using ECG derived respiration.

The alarming rate of mortality and disability due to Chronic Obstructive Pulmonary Disease (COPD) has become a serious health concern worldwide. The progressive nature of this disease makes it inevitable to detect this disease in its early stages, leads to a greater demand for developing non-obstructive and reliable technology for COPD detection. The use of highly patient-effort dependent, time-consuming, and expensive methods are some major inherent limitations of previous techniques. Lack of knowledge about the disease and inadequacy of proper diagnostic tool for early detection of COPD is another reason behind the 3rd leading cause of death worldwide. For this reason, this study aims to explore the utility of ECG Derived Respiration (EDR) for classification between COPD patients and normal healthy subjects as EDR can be easily extracted from ECG. ECG and respiration signals collected from 30 normal and 30 COPD subjects were analysed. Error calculation and statistical analysis were performed to observe the similarity between original respiration and EDR signal. The morphological pattern changes of respiration and EDR signals were analysed and three different features were extracted from those. Classification was performed by different classifiers employing Decision Tree, Linear Discriminant Analysis (LDA), Support Vector Machine (SVM) and K-Nearest Neighbor (KNN). Apart from obtaining comparable classification performance it was seen that EDR has better potential than the original respiration signal for classification of COPD from normal population.

Effect of doxycyline in chronic obstructive pulmonary disease - An exploratory study.

PURPOSE: Various mechanisms, including oxidative stress, inflammation, and protease-antiprotease imbalance are proposed for the progressive decline in lung function in chronic obstructive pulmonary disease (COPD). Doxycycline, a broad spectrum tetracycline antibiotic, is reported to have non-antimicrobial matrix metalloproteinases (MMP) inhibitory action in various inflammatory conditions. The effect of doxycycline in COPD is hereby assessed in the present randomized prospective study. PATIENTS AND METHODS: The first group of COPD patients (n = 30; mild (n = 3), moderate (n = 6), severe (n = 7), very severe (n = 14) as per GOLD II & III criteria was prescribed the standard therapy, a combination of (i) short acting anti-muscarinic agent (SAMA) + short acting ß2 agonist (SABA) inhaled and (ii) corticosteroid inhaled (ICS) + long acting ß2 agonist (LABA) (iii) ICS + LABA + LAMA. Whereas doxycycline (100 mg), was used daily once or twice as per Body Mass Index (BMI), as an add-on to existing standard therapy for the second group of patients (n = 30; mild (n = 2), moderate (n = 7), severe (n = 8), very severe (n = 13). All recruited patients were followed-up after 3 months of treatment. Lung function index FEV1(%) predicted, FEV1/FVC (%), quality of life status including COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ) were assessed. Routine blood cell count also was performed. RESULTS: Biochemical analysis included estimation of oxidative stress markers, inflammatory cytokines and proteases in plasma of both the groups. Reduction in oxidative stress is evidenced by a significant decrease in Lipid hydro peroxides (LPO), total oxidative stress (TOS) and increase in glutathione peroxidase (GSH-PX), reduced glutathione (GSH) and total anti-oxidant capacity (TAO) nitrite and nitrate (NOx) along with peroxynitrate following 3 months of add-on doxycycline treatment. Reduced levels of cytokines such as interleukin IL-6, TNF-α, IL-8 were also observed. Multivariate analysis identified TNF-α major effective discriminant among pre and post doxycycline treated COPD patients. The expression of TNF-α was inversely correlated with FEV1/FVC (%) changes. The levels of MMP-2 and MMP-9/tissue inhibitors of metalloproteinases (TIMP)-1 ratio (MMP-9/ TIMP-1), also decreased significantly and the decline could be associated with TOS. A significant increase in bilirubin and reduced glutathione (GSH) level was noticed in standard therapy group. CONCLUSION: These data suggest that the improvement in lung function and quality of life in COPD patients may probably be attributed to the antioxidant, anti-inflammatory and anti-MMP activity of doxycycline. The potential therapeutic role of long-term doxycycline, in addition to its traditional antibiotic effect, definitely warrants further attention.