Investigating the role of symptom valorisation in tuberculosis patient delay in urban areas in Portugal

Tuberculosis (TB) remains one of the main causes of death worldwide [1]. In 2021, TB was the second cause of death regarding infectious diseases, only surpassed by COVID-19 [1]. In Portugal, the incidence rate of TB was, in 2021, 13.5 cases per 100,000 inhabitants [2]. Although it has been decreasing, it remains one of the highest in the European Union [1]. Diagnosis delay is an important contributor to disease transmission and is related to a higher morbimortality and the emergence of resistant mycobacteria [3‐6]. Diagnosis delay corresponds to the period between symptom onset and diagnosis confirmation or treatment initiation. This period is typically divided in two components: patient delay (from symptom onset to the first medical appointment) and health services delay (from the first medical appointment to the diagnosis or treatment initiation) [7]. Shorter patient delays have been associated with male sex, younger age, higher education and higher knowledge about the disease [3, 7‐11]. On the contrary, longer patient delays have been associated to being unemployed or homeless, having a lower income, residing in rural areas, and consuming tobacco, alcohol or other drugs [4, 12].

Unlike the incidence of the disease, the median patient delay has been rising in Portugal, from 40 days in 2010 to 51 days in 2021 [2]. The delay in seeking medical attention depends on the patient’s ability to recognise symptoms, acknowledgement of a possible illness, assessment of the need for professional care, and overcoming obstacles in obtaining that care [13]. Several interpretative theories have been developed to explain this process, proposing three phases in symptom appraisal: detection, interpretation and response [14]. Regarding detection and interpretation, previous studies assessing patient experiences demonstrated that when experiencing TB symptoms, patients frequently delayed their visit to the doctor because they considered symptoms like cough or lack of strength too unspecific or insufficient to motivate a medical appointment [3, 7, 10, 15]. Their perception was that they had a mild disease, likely a viral infection, that would resolve on its own [8‐11]. In fact, the presence of mild or unspecific symptoms is associated with a longer patient delay and can be connected to lower symptom valorisation [16‐18]. In previous studies, symptom valorisation has been reported as influenced by age, gender and sociocultural context [19‐24]. Women frequently assume a role of managing their health and the health of their families, thus acquiring a higher degree of bodily awareness that influences symptom perception [19‐21]. On the contrary, lower education was related to a lower capability of evaluating symptoms as a warning of a potentially serious disease [20]. This capability of recognising and interpreting symptoms also determines the individual’s attitudes when seeking healthcare, thus being critical for patient delay [13]. Additionally, the phase of responding to symptoms is importantly tied to the availability and access to healthcare, that is conditioned by economic and ethnic factors, as well as by stereotypes in relation to certain diseases, like human immunodeficiency virus (HIV), substance use disorders, cancer or TB [25].

Vast research on total, patient and health services delays have been conducted. However, few studies have assessed symptom valorisation and its effect on patient delay. Analysing this association while characterising the group of patients who disregard their symptoms is of utmost importance, since it provides useful information for developing public health interventions directed at shortening patient delay periods.

With this study, we aim to analyse the association between symptom valorisation and patient delay (objective 1) and to characterise individuals that disregarded their symptoms (objective 2).

The questionnaire was applied to 114 individuals, with 39 being excluded from the current study (Fig. 3).

This analysis included 75 patients with a median age of 50.0 (IQR 41.0 – 60.0). Most of the respondents were men (76.0%), resided in Oporto (58.7%), and the majority (91.7%) went to the doctor when first addressing their symptoms. We obtained a median patient delay of 25.0 days (IQR 11.5 – 63.5), with 56.0% of the participants having a patient delay superior to 21 days. Overall, the knowledge level about TB was good, with a median score of 4.0 out of 5.0 (IQR 3.0 – 5.0). Lack of symptom valorisation was verified in 38.7% of the patients (Table 1).

The included and the excluded groups differed in the number of symptoms reported (p < 0.001), first appointment unit (p = 0.002), symptom valorisation (p < 0.001) and patient delay categorised on 21 days (p = 0.006). The remaining variables had no significant differences (Additional file 3).

Our findings reveal that patients who did not value their symptoms had a significantly higher proportion of patient delay superior to 21 days than patients who valued their symptoms. Additionally, we identified that smokers had a higher prevalence of not valuing their symptoms while living in Oporto and higher household incomes were associated with symptom valorisation.

The association between symptom valorisation and patient delay highlights the importance of symptom recognition in the timely diagnosis of TB. The patients who did not value their symptoms may have perceived them as mild and the severity of their disease to be low, as has been previously reported in the literature [10, 11]. TB initial symptoms are often interpreted as normal or common cold, which, allied to self-medicating, leads to patient diagnosis delay [3, 39]. These patients may not have considered themselves at risk of developing TB, therefore not seeking prompt medical care [17]. Hence, measures for increasing public awareness about the symptoms of TB and emphasising the need to seek early care should be developed and implemented.

Regarding the cut-offs used to categorise patient delay, there is no established period of diagnosis delay that is deemed to be acceptable. However, from a disease transmission control point of view, the period for total diagnosis delay should not surpass four weeks (28 days) [12], hence the period for patient delay should be inferior. In this case, it is likely that the 30-day cut-off was too wide, classifying prolonged periods as acceptable. The 21-day cut-off is perhaps more accurate at identifying prolonged patient delays, hence a reference cut-off for patient delay should not be superior to 21 days. Nevertheless, we also note that the obtained confidence intervals were quite wide, so it is possible that this study might not have had sufficient power. Further investigation in defining cut-offs for diagnosis delay is needed, as it is useful both for academic research and clinical practice [5]. Also, if patients were provided with an accurate cut-off from which they knew they should seek medical care regarding their symptoms, the patient delay period could decrease, assuming that timely access to healthcare is guaranteed [5].

Although symptom disregard has been related to a possible lack of knowledge about the disease [40] or a lower level of education [20], neither were significant in our analysis. Nevertheless, we identified other sociodemographic factors associated with symptom valorisation. Patients who lived in Oporto valued symptoms more than those living in Lisbon. Marco de Canaveses and Penafiel, two cities in Oporto metropolitan area, present the highest TB incidence rates in the country (respectively, 52.7 and 55.9 cases per 100,000 inhabitants) [2]. Hence Oporto population may be more aware of the existence of this disease, valuing its symptoms [2]. Besides, the Oporto metropolitan area has registered better indicators of access to healthcare when compared to Lisbon [28]. In 2019, in Portugal, the North region had the highest percentage of patients with an assigned family doctor (98.4%). On the contrary, Lisbon and Tagus Valley had the lowest (85.6%) [28]. Despite this difference, we do not think this may have affected our results, given that none of our participants referred difficulties scheduling a medical appointment, neither because there was a delay of the services nor because these services were not available or distant. Nevertheless, in 2021, 52.7% of the TB patients in the Lisbon district were immigrants, as opposed to only 5.8% in the Oporto district [2]. The immigrant population represents a challenge to implementing TB control programs, as it is a vulnerable group with inherent difficulties accessing healthcare [41]. Immigrant population showed, in 2021, a TB notification rate 3.8 times higher than the national average (55.8 per 100,000 inhabitants), with a progressive increase in the proportion of cases, reaching 25.8% in the same year [2]. Therefore, the regional asymmetries regarding symptom valorisation should be addressed in future investigations to clarify whether these are linked to unequal healthcare access or other non-explored factors. Patients who earned a higher household income also had a lower prevalence of lack of symptom valorisation. Earning a higher household income has been associated with higher education and higher health literacy levels [42, 43], which promotes appropriate help-seeking behaviour and improves access to healthcare [44‐46]. On the opposite, patients who smoked had a higher proportion of symptom disregard. Although being more likely to experience respiratory symptoms than non-smokers, smokers are less concerned by these, therefore they do not seek the help they require [47]. This is also true for other chronic diseases that, like pulmonary TB, are characterised by persistent cough [7]. These findings suggest the need for targeted health education interventions to improve symptom recognition and valorisation, especially among patients with chronic respiratory diseases or smokers. This is important in the studied regions, with the metropolitan area of Lisbon presenting, in 2019, a prevalence of smokers of 18.2% and the North region, a prevalence of 16.2% [48].

Our study has some limitations. We could not establish temporal relationships due to its design. Additionally, we were working with information that was self-reported by the patients, which may have introduced a recall bias. For example, patients who did not value their symptoms may be less precise in reporting their onset of symptoms date. In fact, this date is hard to define, as it is, regarding TB’s frequent insidious presentation, which may underestimate patient delay. Moreover, the considered outliers of patient delay of zero or superior to 365 days are, in fact, possible. Even so, we considered that, especially for typically insidious diseases like TB, the first phases of symptom appraisal (detection and interpretation that lead to a response) should take more than 24 h, hence classifying zero days patient delays as unplausible. Likewise, we viewed as unlikely that patient delays superior to 365 days should occur and that these could represent errors in the introduction of the symptom onset or first medical appointment dates, either during data collection or during its introduction in the database, that could have tampered with our results. Also, the process of recruitment of participants was below expectations. In 2020 only, in Lisbon and Oporto districts, there was a total of 809 new TB notifications [26]. During the whole data collection period, we were only able to assemble 114 respondents. The data collection occurred during the COVID-19 pandemic when our interviewers from local public health units were deviated to other tasks related to pandemic control, thus conditioning the application of the questionnaire. In fact, we only registered five answered questionnaires during the pandemic period, therefore we consider that the impact of this context in our results was mainly in terms of a lower number of participants and was not related to an overestimation of patient delay, for example, due to the conditioned response of healthcare services during the pandemic. Despite the low participation, our sample has similar characteristics when compared to the population of TB patients in the studied regions: approximately 70% of the cases are men, with a median age of 50 years old [2, 4]. Moreover, the existence of missing information in some variables lead to a smaller sample in the multivariable analysis. Finally, we did not find an association between symptom valorisation and the unit of the first appointment. However, the interpretation of the answer options to the question that originated this variable is not unequivocal. The option “hospital” was meant for a non-urgent medical appointment at a hospital setting, though we cannot assure that this was explained during data collection and that subjects responded accordingly. There may have been a misclassification where people intended to answer “hospital emergency services” but instead answered “hospital” which prevents us from detecting an association.

This study also has several strengths. To the best of our knowledge, it is the first study to directly evaluate symptom valorisation and its association with TB patient delay in Portugal, providing new and valuable information. We also identified some factors associated with symptom valorisation, offering a base for future targeted health education campaigns to reduce patient delay, particularly among vulnerable populations.

TB remains a significant global public health issue and timely diagnosis is crucial for reducing its transmission, morbidity and mortality. We found that a lack of symptom valorisation was associated with longer patient delay periods and identified that living in Oporto and higher household incomes were associated with symptom valorisation while smokers had a higher prevalence of symptom disregard. These findings emphasise the importance of the socioeconomic determinants of health and draw attention to tobacco as a risk factor both for TB and for diagnosis delay, justifying the implementation of anti-tobacco measures and interventions. Additionally, targeted education campaigns to improve symptom recognition should be implemented, mainly regarding smokers or patients with respiratory chronic diseases. It should be explained to patients that a new, persistent cough or a change in their usual cough pattern should alert them to seek medical care, as it may represent a potentially serious illness (flu, COVID-19, cancer or TB, for example).