Quality of life after pulmonary embolism: the development of the PEmb-QoL questionnaire

Authors


Danny M. Cohn, Department of Vascular Medicine, Academic Medical Center, Room F4-139, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands.
Tel.: +31 20 5667516; fax: +31 20 5669343.
E-mail: d.m.cohn@amc.uva.nl

We are currently developing a disease-specific questionnaire to measure quality of life after pulmonary embolism (PE). The aim of this letter is to invite colleagues to cooperate on the validation of our questionnaire.

PE is a rather common disease, with an annual incidence of approximately 0.5 per 1000 persons in Western countries [1]. As PE shares many features with deep vein thrombosis (DVT), both diseases are considered to be different manifestations of the same entity: venous thromboembolism (VTE) [2]. PE and DVT share the same risk factors, such as thrombophilia, pregnancy, cancer, surgery, immobilization, and oral contraceptive use. Furthermore, both manifestations occur in venous blood and coincide frequently [3–5]. Accordingly, treatment recommendations are similar [2].

PE is a leading cause of mortality and morbidity: death occurs in about 15% of cases within 6 months of its presentation [6]. In addition, VTE often can be considered a chronic disorder: recurrence is common, with an incidence of approximately 30% within 10 years [7,8]. Moreover, residual complaints (known as post-thrombotic syndrome) are reported in 30% of patients with DVT within 2 years after the initial event, despite the use of compression stockings [9]. The most important long-term complication of PE is chronic pulmonary hypertension (which may manifest as fatigue, limited exercise tolerance or shortness of breath), which was shown to affect 3.8% of PE patients within 2 years following the initial event in one study [10].

Quality of life is conceptualized increasingly as the central outcome of health care. ‘Perceived health, health-related quality of life, and health-state utilities bring health assessment progressively closer to the patient’s perspective’, is a conclusion in a paper by Sullivan on taking the patient’s point of view regarding health care and health into account [11]. To illustrate the gained interest in quality of life, we performed a broad-brush search in Medline with the MeSH term ‘quality of life’. This yielded 7143 articles published in 2007, compared with 4923 in 2002. Surprisingly, a more sophisticated search without any restriction yielded not a single publication on quality of life after PE (neither by a disease generic questionnaire, nor by a disease specific questionnaire). In contrast, quality of life following DVT has been the subject of investigation and several DVT-specific questionnaires have been developed over the past decade [12–16].

We aimed to develop a disease-specific questionnaire to assess quality of life after PE using the principles of grounded theory. We performed qualitative, semi-structured interviews in 10 outpatients (4 males/6 females) whom we selected for the gravity of their complaints following PE. These patients did not have other cardiopulmonary diseases that might have resembled PE-related complaints. Two investigators (LB and EN) visited the subjects at their homes and structured the interviews into social functioning, physical complaints and emotional disturbances. The interviews were tape-recorded with consent and transcribed later. Characteristics of the interviewed patients are listed in Table 1. The most remarkable complaints were shortness of breath/difficulty in breathing, fatigue, fear of recurrence after discontinuing anticoagulant treatment, more readily emotionally disturbed (which bothered a subgroup of the patients) and more social isolation than prior to the PE. The authors (of whom two are experienced clinicians with a specific interest in patients with VTE) remodeled the outcomes of the interviews into the draft questionnaire.

Table 1.   Characteristics of interviewed patients
 Gender, age (years), marital status
PE event

Main functional complaints

Main psychological complaints

Main social limitations
1Female, 37, married7 months prior to interview. Massive PE, resuscitatedFatigue, muscle weaknessAnxiety: more readily emotional; fear of recurrent PE; worried about stopping anticoagulant treatmentAfraid of being a burden for relatives and friends, afraid of being alone
2Male, 31, unknown6 years prior to interview first PE; two recurrences (22 months and 7 months respectively)Pain behind the shoulder blades, pain in the chest, tiredness, difficulty in breathingFear of recurrent PE, more readily emotional (experienced as annoying), depressedNot able to work, limited in social contacts
3Female, 84, widow1 year ago PEFatigue, not able to exert herselfDepressed (at times)Becomes easily weary after having a visit from friends/relatives
4Female, 43, marriedPE at 13 months and 5 months prior to the interview Pain in the back and fatigueFear of recurrence, depressed feeling, more readily emotionalAvoids visits to friends and shopping in the center of the city, which is too exhausting
5Female, 73, widowPE 4 years prior to the interviewBreathlessness, sensation of pressure, fatigueFear of recurrenceMore socially isolated, limited in taking a trip
6Female, 32, singlePE 14 months prior to PEDifficulty in breathing, pain at the back and between shoulder bladesAnxious about recurrence, worried about stopping anticoagulant treatmentNo complaints
7Male, 34, marriedPE 4 months prior to interviewDifficulty in breathing, fatigue, shortness of breath, pain behind shoulder blades, chest painFear of recurrence, more readily emotional (which bothers the patient)Feeling of lack of attention to his children, not able to work, not able to have visitors too often (too exhausting)
8Male, 63, marriedPE 13 months prior to interviewShortness of breath, tired, difficulty in breathingMuch more emotionally disturbedNot able to perform as much as he intends
9Female, 79, widowFirst PE 7 years prior to interview, recurrent PE 6 yearsDifficulty in climbing stairs and fatigue, shortness of breathNo typical complaintsNo typical complaints
10Male, 55, marriedPE 18 months prior to interviewMore easily tired, difficulty in breathing following exercise, chest painAfraid of a recurrent PE, worried about stopping anticoagulant treatmentPrefers staying at home

The original version was developed in Dutch. For the creation of the English version, the Dutch version was independently translated by two native English speakers and subsequently back-translated by a third native English speaker. The structure of the questionnaire, which we named PEmb-QoL (Pulmonary Embolism Quality of Life), was modeled in line with the existing generic SF-36 (short form 36) questionnaire and the disease-specific VEINES-QOL/Sym questionnaire, which has been developed for DVT. The PEmb-QoL currently contains 10 questions (40 items) covering six dimensions: frequency of complaints (eight items), activities of daily living (ADL) limitations (13 items), work-related problems (four items), social limitations (one item), intensity of complaints (two items) and emotional complaints (10 items). Two questions provide descriptive information. The PEmb-QoL is a self-administered questionnaire, in line with the SF-36 and Veines-QOL/Sym questionnaires.

Our future aims are to further validate this questionnaire. We are currently distributing the PEmb-QoL questionnaire amongst patients with a recent PE to assess construct validity. The PEmb-QoL questionnaire will be distributed together with the disease generic SF-36 questionnaire to measure its responsiveness. A subgroup of patients with PE will receive the PEmb-QoL a second time for analysis of the test–retest reliability.

At present, it is too early to consider this questionnaire a useful measure. However, to avoid duplication of efforts, we would like to offer the current version of the PEmb-QoL questionnaire to colleagues who are working in this field, in order that it might be further validated.

Acknowledgements

Dutch Heart Foundation (project no. 2006B056). Dutch Organisation for Health Research and Development (ZonMw) (project no. 945-06-604).

Disclosure of Conflict of Interests

The authors state that they have no conflict of interest.

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