Variabilidad en la EPOC. Una visión a través del estudio PLATINO

Variabilidad de síntomas en pacientes ambulatorios con EPOC y validación del Instrumento colombiano de variabilidad de síntomas en EPOC (CoVaSy)

Introducción. Se considera que la variabilidad de los síntomas respiratorios de la enfermedad pulmonar obstructiva crónica (EPOC) es baja o inexistente. Sin embargo, algunos autores afirman que se pueden presentar fluctuaciones. Objetivos. Describir la variabilidad de síntomas en pacientes con EPOC a lo largo del día y la noche durante cuatro semanas mediante un diario de paciente y validar un cuestionario desarrollado para tal fin (el Instrumento Colombiano Autoadministrado de Variabilidad de Síntomas en EPOC - EPOC-CoVaSy) Materiales y métodos. Estudio de cohorte realizado en 96 pacientes con EPOC atendidos entre junio y diciembre de 2016 en el Centro de Atención Pulmonar - CAP, en Barranquilla, Colombia, quienes diligenciaron un diario de paciente durante cuatro semanas y, luego de este periodo, el instrumento auto administrado EPOC-CoVaSy. La independencia y comparación de frecuencias de las variables categóricas y continuas se establecieron mediante las pruebas χ² y exacta de Fisher y el coeficiente de correlación de Pearson, respectivamente. Se realizó un MANOVA, utilizando modelos de regresión lineal, para determinar las correlaciones entre los resultados del diario y el instrumento. Resultados. La edad promedio de los participantes fue 73.3±8.3 años y 71.87% eran hombres. Según el análisis de los diarios, los puntajes promedio (escala visual analógica) para todos los síntomas y desempeño de actividades diarias oscilaron entre 0.5 y 2.5 siendo más altos en la mañana (puntajes promedio entre 1.5 y 2.5) que en la tarde y noche (puntajes promedio entre 0.5 y 1.5), sin embargo esta variabilidad fue mínima, lo que coincidió con los resultados obtenidos en el EPOC-CoVaSy, evidenciándose una alta correlación entre ambos instrumentos, lo que permitió confirmar que la herramienta diseñada es útil para medir dicha variabilidad. Conclusiones. Con base en los hallazgos del presente estudio, se puede concluir que existe una leve variabilidad en los síntomas de EPOC a lo largo del día, la cual debe considerarse a la hora de establecer esquemas de tratamiento para esta enfermedad. Asimismo, se estableció que el EPOC-CoVaSy es válido para medir dicha variabilidad en la población colombiana con EPOC.

Genetic Factors Associated with COPD Depend on the Ancestral Caucasian/Amerindian Component in the Mexican Population

Genetic variability influences the susceptibility to and severity of complex diseases; there is a lower risk of COPD in Hispanics than in non-Hispanic Caucasians. In this study, we included 830 Mexican-Mestizo subjects; 299 were patients with COPD secondary to tobacco smoking, and 531 were smokers without COPD. We employed a customized genotyping array of single nucleotide polymorphisms (SNPs). The population structure was evaluated by principal component analysis and allele association through a logistic regression model and haplotype identification. In this study, 118 individuals were identified with a high Caucasian component and 712 with a high Amerindian component. Independent of the ancestral contribution, two SNPs were associated with a reduced risk (p ≤ 0.01) of developing COPD in the CYP2A6 (rs4105144) and CYP2B6 (rs10426235) genes; however, a haplotype was associated with an increased risk of COPD (p = 0.007, OR = 2.47) in the CHRNA5-CHRNA3 loci among smokers with a high Caucasian component. In Mexican-Mestizo smokers, there are SNPs in genes that encode proteins responsible for the metabolism of nicotine associated with a lower risk of COPD; individuals with a high Caucasian component harboring a haplotype in the CHRNA5-CHRNA3 loci have a higher risk of suffering from COPD.

Effect of the Application of the Global Lung Initiative 2012 Spirometry Reference Equation on the Diagnosing and Classifying Degree of Airway Obstruction in Thai Adults Aged 40 to 80 Years Old

Background and objective: Changing to a different spirometry reference equation can result in misinterpretation of spirometric findings. Currently, there is limited data about any discordance between the interpretations of airway obstruction (AO) using the Global Lungs Initiative (GLI) 2012 and the currently employed Thai reference equations (Siriraj) in Thai adults. Therefore, this study aimed to determine differences in diagnosis around AO and classification of the severity of AO using the GLI2012 and Siriraj reference equations in Thai adults. Materials and Methods: We analyzed spirometric results from Thai adults aged 40–80 years old (n = 2084), which were collected at the Lung Health Center, Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand between January 2005 and December 2015. The diagnoses concerning the AO were interpreted using the GLI2012 and Siriraj reference equations. The severity of AO in each case was classified into five grades, including mild, moderate, moderately severe, severe, or very severe. McNemar’s test was used to analyze differences in diagnosis of AO and classification of the level of severity. The Kappa statistic was used to determine agreements of diagnosis of AO and classification of severity between the two reference equations. Results: There were significant differences in both diagnosis of AO and their classifying severity level between the two reference equations (p-value < 0.001). However, the levels of agreement between the two reference equations were moderate to very good in different age and sex groups (Kappa values ranged from 0.62 to 0.78 for the diagnosis of AO and 0.54 to 0.89 for the classification of severity). Conclusions: Changing from the Siriraj to the GLI2012 reference equations underestimates the proportion of airway obstruction in Thai adults.

Physician-Patient Concordance in Pharmacological Management of Patients with COPD

A retrospective analysis of a cross-sectional, multicenter survey was conducted in United States (US) medical practices to evaluate the concordance between patients with COPD and their physicians on disease-specific characteristics. Associations between patient and disease-related characteristics with monotherapy, dual therapy, or triple therapy prescribed as COPD maintenance regimens were also examined. Eligible physicians completed patient record forms (PRFs) for up to 6 consecutive patients with COPD. Patients for whom a PRF was completed were invited to complete a patient self-completion (PSC) survey consisting of questions similar to those on the PRF, as well as several validated measures to assess the impact of COPD on patients' lives. A total of 469 patients completed a PSC that was matched with the PRF completed by their physician, forming the sample for the concordance analysis. Moderate agreement (kappa (κ) = 0.41-0.60) was observed for 79% of measures, with the lowest concordance rating corresponding to hemoptysis (κ = 0.22). There were few differences in demographic or clinical characteristics between patients prescribed monotherapy and dual therapy. Triple therapy rather than monotherapy or dual therapy was more often prescribed for patients with greater frequency of symptoms, negative impact of COPD on daily life and interpersonal relationships, and respiratory impairment based on the most recent FEV1. Diverse factors influence US physicians' perceptions of disease and treatment choices, including patient symptoms, quality of life, and disease impact. Our results highlight that concordance between physicians and patients regarding symptoms and physical function may contribute to optimal management of COPD.

Moving towards patient-centered medicine for COPD management: multidimensional approaches versus phenotype-based medicine--a critical view

For decades, chronic obstructive pulmonary disease (COPD) has been considered a relentlessly progressive disease in which the deterioration of lung function is associated with an increase in symptoms, interrupted only by periods of exacerbation. However, this paradigm of COPD severity based on FEV1 has been challenged by currently available evidence. So far, three main approaches, though with contradictory aspects, have been proposed in order to address the complexity of COPD as well as to develop appropriate diagnostic, prognostic and therapeutic strategies for the disease: 1) the use of independent, clinically relevant variables, 2) the use of multidimensional indices, and 3) disease approaches based on clinical phenotypes. Multivariable systems seem superior to FEV1 in predicting prognosis and defining disease severity. However, selection of variables available from current literature must be confronted with issues of medical practice. Future evidence will be needed to reveal their effective relationship with disease long-term prognosis and to demonstrate the most adequate cutoff values to be used in clinical settings. Multidimensional scores provide a good prognostic instrument for the identification of patients with a particular degree of disease severity. Clinical phenotyping can help clinicians identify the patients who respond to specific pharmacological interventions; however, there is some controversy about the phenotypes to select and their long-term implications. Although these approaches are not perfect, they represent the first step towards patient-centered medicine for COPD. In the near-future, these different approaches should converge towards one new field to focus on the better management of COPD patients.

Comorbidities and health status in individuals with and without COPD in five Latin American cities: the PLATINO study

INTRODUCTION

Comorbidities are common in patients with chronic obstructive pulmonary disease (COPD), and have a significant impact on health status and prognosis. The PLATINO study provides data on self-reported comorbidities and perceived health status in COPD subjects.

METHODS

PLATINO is a population-based study on COPD prevalence in five Latin American cities. COPD diagnosis was defined by GOLD criteria (FEV1/FVC<.70 post-bronchodilator). Information was collected on the following comorbidities: heart disease, hypertension, diabetes, cerebrovascular disease, peptic ulcer and asthma. Health status was evaluated using the SF-12 questionnaire, derived from the question: «In general, would you say your health is excellent, very good, good, fair or poor?». A simple comorbidity score was calculated by adding the total number of comorbid conditions.

RESULTS

Of a total population of 5314individuals, 759 had COPD. Reported comorbidities by decreasing frequency were: any cardiovascular disease, hypertension, peptic ulcer, heart disease, diabetes, cerebrovascular disease, asthma and lung cancer. COPD patients had a higher comorbidity score and prevalence of lung cancer (P<.0001) and asthma (P<.0001), as well as a higher tendency to have hypertension (P=.0652) and cerebrovascular disease (P=.0750). Factors associated with comorbidities were age, body mass index (BMI) and female gender. The number of comorbidities increased as the health status deteriorated.

CONCLUSIONS

In the PLATINO population-based study, COPD individuals had an increased number of comorbidities. Age, female gender and higher BMI were the factors associated with comorbidity in these patients. Comorbid conditions were associated with impaired health status, independently of the COPD status.