title: Decreased work ability associated to indoor air problems--An intervention (RCT) to promote health behavior.
abstract: BACKGROUND
  Indoor air problems may induce respiratory irritation and inflammation. In occupational settings, long-lasting non-specific building-related symptomatology, not fully medically explained, is encountered. The symptomatology may lead to illness, avoidance behavior and decreased work ability. In Finland, investigations of workers suspected of occupational asthma have revealed excess disability. There are no well-established clinical practices for the condition.
  
  
  OBJECTIVE
  The aim was to develop a clinical intervention for patients with non-specific indoor air-related symptoms and decreased work ability.
  
  
  METHODS
  A randomized controlled trial including psychoeducation and promotion of health behavior was carried out in 55 patients investigated for causal relationship between work-related respiratory symptoms and moisture damaged workplaces. Inclusion criteria for disability was the work ability score (WAS)≤7 (scale 0-10) and indoor air-related sick leave ≥14 days the preceding year. After medical evaluation and the 3-session counseling intervention, follow-up at 6-months was assessed using self-evaluated work-ability, sick leave days, quality of life, and illness worries as outcome measures.
  
  
  RESULTS
  The mean symptom history was 55.5 months. 82% (45 out of 55) had asthma with normal lung function tests in most cases, although reporting abundant asthma symptoms. 81% of patients (39/48) had symptomatology from multiple organ systems without biomedical explanation, despite environmental improvements at work place. At the psychological counseling sessions, 15 (60%) patients of the intervention (INT, n=25) group showed concerns of a serious disease and in 5 (20%), concerns and fears had led to avoidance and restricted personal life. In the 6-month follow-up, the outcomes in the INT group did not differ from the treatment as usual group.
  
  
  CONCLUSIONS
  No intervention effects were found. Patients shared features with medically unexplained symptoms and sick building syndrome or idiopathic environmental intolerance. Long environment-attributed non-specific symptom history and disability may require more intensive interventions. There is a need for improved recognition and early measures to prevent indoor-associated disability.
  
  
  BACKGROUND
  Single-center randomized controlled trial (ISRCTN33165676).
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: aki.vuokko@ttl.fi.
authors.forename: Aki
authors.initials: A
authors.lastname: Vuokko
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: sanna.selinheimo@ttl.fi.
authors.forename: Sanna
authors.initials: S
authors.lastname: Selinheimo
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: markku.sainio@ttl.fi.
authors.forename: Markku
authors.initials: M
authors.lastname: Sainio
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: hille.suojalehto@ttl.fi.
authors.forename: Hille
authors.initials: H
authors.lastname: Suojalehto
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: heli.jarnefelt@ttl.fi.
authors.forename: Heli
authors.initials: H
authors.lastname: Järnefelt
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: marianna.virtanen@ttl.fi.
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland.
authors.forename: Eila
authors.initials: E
authors.lastname: Kallio
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: christer.hublin@ttl.fi.
authors.forename: Christer
authors.initials: C
authors.lastname: Hublin
authors.affiliation: Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, 00250 Helsinki, Finland. Electronic address: kirsi.karvala@ttl.fi.
authors.forename: Kirsi
authors.initials: K
authors.lastname: Karvala
mesh_terms: D000328:Adult; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D015438:Health Behavior; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011613:Psychotherapy / Q000379:methods*; D012120:Respiration Disorders / Q000209:etiology; D062707:Return to Work; D057566:Self Report; D018877:Sick Building Syndrome / Q000209:etiology / Q000523:psychology / Q000628:therapy; D016896:Treatment Outcome; D055815:Young Adult
keywords: Idiopathic environmental intolerance; Indoor air; Occupational asthma; Quality of life; Randomized control trial; Sick building syndrome; Water damaged buildings; Work ability; Work-related respiratory symptoms