The World Health Organization (WHO) predicts that within a few years chronic obstructive pulmonary disease (COPD) will become the third leading cause of death worldwide.1 Its prevalence will increase in coming decades due to the persistently high numbers of smokers and population aging, both situations being particularly relevant in women.1 COPD exacerbations are common events in the natural history of the disease, and many patients require admission to hospital, generating a heavy burden on both patients and the system.2–4 A careful characterization of patients admitted for COPD exacerbation is essential when planning comprehensive care of the disease and the provision of more individualized and efficient management.2,5

The demographic and clinical characteristics of these patients have been determined, but there is less evidence on their social characteristics, a dimension that includes available resources, dependency, disability, risk of social exclusion, frailty, and autonomy.6–8 COPD causes progressive physical and mental limitations that hinder the performance of basic and instrumental activities of daily living and determine the need for assistance in these tasks, which can damage social relationships.8–11 The benefit that might be obtained by balancing this dimension could be as important for the patient as improvement in lung function.8,9 The available health and social welfare data are heterogeneous, and are derived mainly from elderly outpatients with a significant comorbidity burden admitted to internal medicine departments, and data obtained more than a decade ago.12,13 Information on social frailty could help predict events such as readmission and mortality that cannot currently be reliably anticipated on the basis of available demographic and clinical factors.13–16 In fact, some integrated care proposals recommend the systematic assessment of social frailty using specific questionnaires and scales.16,17

There has been growing interest in the impact of gender on COPD in recent years, particularly susceptibility, prevalence, diagnosis, comorbidities, and prognosis, but rarely social aspects.19,20 However, this type of assessment is considered a key element in health planning in the era of chronicity.21,22

Analyzing the social characteristics of patients with severe COPD exacerbations, in addition to their demographic and clinical characteristics, will provide much needed information for designing more personalized and efficient care programs.

This was a cross-sectional study describing the initial stages of follow-up of a cohort of patients (the SocioEPOC cohort) admitted for COPD exacerbations. Patients were recruited prospectively and consecutively in a third-level hospital which has a reference population of 375000 inhabitants in both urban and rural areas.

STROBE guidelines23 were followed for the study methodology and reporting of results.

A total of 253 patients were included in the study, of which 58 (23%) were women. Five patients (2 women) were excluded: 2 because of the severity of their situation, and another 3 who refused to participate. Demographic and clinical characteristics, overall and by sex, are shown in Table 1.

Patients had a mean age of almost 70 years, the majority had completed only primary education, and half lived in a rural environment. Four resided in hostels (1.6%) and 2 (0.8%) in care homes. Most were overweight or obese, and had functionally severe COPD and stable dyspnea (mMRC grade 2–3). In the vast majority of patients, COPD was mainly caused by smoking; nearly 40% continued to smoke actively, and 20% drank alcohol excessively. Less than 10% were drug users, most of whom were on methadone programs, and only 6 frequently consumed other toxic substances, such as heroin or cocaine. Although the Charlson index is low, slightly more than half of the cohort had cardiovascular comorbidities, half had anxiety or depression, and between 20% and 25% had diabetes, sleep apnea, or mild anemia. A total of 40% were receiving domiciliary oxygen and 15% noninvasive ventilation.

When compared on the basis of sex, women were younger, their COPD was more often due to causes other than smoking, they had a lower pack-year index, more were active smokers, and they drank less excessively. Despite a similar FEV1, they had a lower degree of dyspnea, cardiovascular comorbidities, and sleep apnea. They showed a greater degree of anxiety and less diabetes, but these differences did not reach statistical significance.

With respect to overall social characteristics (Table 2 and supplementary Tables 1–4), most patients were pensioners and more than half had a monthly income of less than €800, 25% lived or slept alone, almost half had some dependency for performing some basic ADLs (52.5% moderate and 18.6% severe), 90% for instrumental ADLs, and 60% had some social or family risk/problem. However, only half had a caregiver, of which 80% were informal, mostly women, and 60% of these caregivers reported some degree of burden. Half of the caregivers were the patients’ own spouses or partners and the other half were mainly daughters or relatives. However, barely 20% of patients had used the social services. Most patients resided less than 20km from the hospital, and one third had their own transportation.

When comparing these characteristics on the basis of sex, women had a lower income, they were more often still in active employment, although a greater percentage did not receive any type of pension, salary or welfare benefits. They slept or lived alone more often and had fewer informal caregivers than men; caregivers were less frequently women, and fewer were their own partners/spouses. Women were less dependent for instrumental domestic tasks, controlling their medication, shopping and financial affairs, and for basic activities related to mobility. They presented a higher social problem/risk in the social and family domains of the Gijón questionnaire.

This study offers a comprehensive description and gender-based comparison of the social, demographic and clinical profiles of patients with severe COPD exacerbations admitted to the respiratory medicine department of a third-level hospital. This is the first study conducted in Spain that addresses the social situation from a gender perspective, using numerous social assessment indices and scales administered by expert personnel.

From a clinical point of view, the main clinical characteristics of the patients included in this study are very similar to those described in the AUDIPOC audits and the Spanish cohort of the pan-European COPD audit, consisting of 3493 and 4650 cases, respectively.34 We believe, therefore, that our study population is a good reflection of patients admitted to other respiratory departments in Spain.

In Spain, less than 20% of patients present COPD as their only chronic disease,35 as shown in this study. Although the average age was less than 70 years and the Charlson index less than 2, most patients presented multiple pathologies that met the criteria of comorbidity defined by the national strategy for care of chronicity of the Ministry of Health, Social Services and Equality.23,35 This document emphasizes the importance of coordinating between health and social services and addressing the problem from a gender perspective.18,23

Almost a quarter of our cohort are women. This percentage is higher than in other Spanish series,7,10,14,33 and may be explained by the period of time covered and by the fact that smoking among women began to rise in our health area earlier than in other regions, as previously described.36 From a demographic and clinical point of view, women in this study are slightly younger, with a lower pack-year index, and more frequently have a etiology other than smoking than men, as has already been described in other studies.19–21 Sixty percent are active smokers, similar to the data published by Mayoralas et al.11 in a large outpatient study of women with COPD. It is likely that other social or psychological determinants found in our study may come into play, in addition to a greater degree of addiction among women. This should compel us to raise awareness about COPD, as other authors suggest, and to implement more successful strategies in the prevention and treatment of COPD in women.12,19–21 In contrast to the findings of other studies,19–21 women with a similar lung function to men had a lower degree of dyspnea. This could be partly explained by the greater frequency of cardiovascular comorbidity among men (data not shown).

With respect to social profiles, our study shows the overall prevalence of disability and dependence for both basic and instrumental activities, loneliness, and social frailty and risk, some of which are noticeably worse in women. The low economic and educational level and major limitations in basic ADLs of COPD outpatients observed in the Spanish EIME study over 10 years ago10 has still prevails today.10 Only 7.5% of the patients included in the EIME study10 lived alone, a finding which contrasts with the 21.4% reported in our cohort. This figure is similar to that described in more recent studies in other countries37 and reflects societal changes in developed countries.23,34 Women have fewer economic resources and help, and more often work actively. They also have less dependence for basic instrumental activities related to household chores and shopping. This could be a result of the above, but may owe more to the roles and stereotypes of our society,22,38 a consideration that has led some authors to recommend evaluating questionnaires on the basis of sex.29

Only 16.3% of women with COPD in the Mayoralas study11 lived alone, compared to 40% of our series, a difference that might be explained by differences in the scope of the study, and that may possibly reflect a poorer social situation among patients with serious COPD exacerbations.35

With respect to non-formal care, women are cared for less frequently by their partners and spouses, so the caregiver burden tended to be lower, perhaps also because of the different social roles and inequalities already described.38

All these factors suggest that women with serious COPD exacerbations are found to be at greater risk of social exclusion when specific questionnaires addressing family and social domains are used – a risk that is generally higher than that described in an older, dependent population of COPD patients with multiple comorbidities.13

Our study has some limitations. Firstly, its single center design may not reflect the social and healthcare reality of other regions of Spain. However, the clinical characteristics of the patients included are similar to those described in extensive audits,34 although the mean age in our study was slightly lower. In addition, our sample size could be too small to adequately compare some variables. Finally, the social aspects (dependence, social frailty and risk of exclusion, caregiver burden) were assessed using scales and questionnaires that have not been widely validated in patients with COPD. The same could be said for the assessment of anxiety and depression. However, as these tools are recommended for use in integrated healthcare processes in COPD and patients with multiple pathologies,17,18 they were used to facilitate future comparisons with other studies and evaluate their usefulness. Finally, we did not evaluate specific factors, such as quality of life, which might be of interest.

The most important advantages of this study include the novel use of social scales administered by expert personnel, consecutive case sampling, which reduces the possibility of selection bias, and the fact that we focus on patients with COPD exacerbations, adding to the relative homogeneity of the study population.

In conclusion, patients with severe COPD exacerbations admitted to respiratory departments are highly dependent, at risk of social exclusion, need the help of caregivers who are often overburdened, and a significant number of them live alone. There are notable gender differences, and women have more limited economic resources and assistance and a worse family and social situation, although they are less dependent for some activities. These inequalities, which seem to go beyond gender differences in COPD manifestation, should be taken into account in the design of comprehensive COPD care programs. The potential weight of social factors in COPD exacerbations opens the door for future studies to determine the involvement of these factors in other events, such as readmissions or mortality, compared to purely clinical variables.

This study was funded by grants obtained from SEPAR (grant 456/2017), FIS-ISCII PI18/01317 (FEDER) and the unconditional collaboration of the company Menarini.

The authors state that they have no conflict of interests.