Questionnaires for clinical and epidemiological

purposes Manon Labrecque,M.D., M.Sc.

Role of Epidemiology in OA

« The discipline of Epidemiology focus on the distribution and determinants of Health-related states and disease in population.”

The determinants are in 2 broad headings Environmental and host factors

In the context of OA, the Environmental factors are thoses encountered in the work place

Work-Relatedness of Airway Disease

ILO suggested the use of following categories (1) conditions caused by agent-specific exposures (2) conditions of multifactorial etiology in wich work

exposure is one of them (3) conditions to which an individual is

susceptible,and the disease is precitated by a work-related exposure

(4)preexisting conditions aggravated by a work-related exposure

(1) Occupation diseases (2-3-4) work-related disease

Outcomes measurements in epidemiological studies of OA

Questionnaire: Advantage of being non invasive and easy to administer and appropriate for population studies

Standardized questionnaire for asthma has been developed and validated in international comparisons

Ref: Burney PGJ Eur Respir J 1989;2:940-945

Questionnaires

Limitation Poor correlation between symptoms and presence or

absence of NSBR NSBR can exist without symptoms Asymptomatic subjects with NSBR can develop

symtoms in subsequent years Sensitivity and specificity in predicting asthma or OA

are variable Subjects can under or overreport their symptoms

depending the circumstances

Questionnaire

From differents Studies we learned that the % of workers proven to be suffering from OA by specific challenge test or peak flow rate recording varies from 2 to 16%

Thus, the questionnaire is a sensitive tool but not a specific one and while invaluable in etiological epidemiological studies in population at riks for OA,it is inadequate on its own for clinical case identification

Algorithm for Case Identification

Questionnaire

Skin or Skin or IT not Feasibleimmunological testingFeasible

Negative Positive Assessment of NSBR Positive

Specific Inhalation Tests and/ or PEFR monitoring

Asthma Questionnaire

Asthma related questions were originally derived from the IUATLD bronchial symptom questionnaire, and included a cluster of five questions that had exhibited the best combination of sensitivity and specificity for the detection of NSBR (referred to as the "discriminant function predictor" or DFP).

Ref: Burney PG. Int J Epidemiol. 1989 Mar;18(1):165-73.

Asthma Questionnaire These questions included(1)Have you ever had trouble with your breathing? (continuously

or repeatedly)(2)Have you had an attack/episode of shortness of breath that

came on following strenuous activity at any time in the last 12 months?

(3)Have you had wheezing or whistling in your chest at any time in the last 12 months?

(4)Have you been awakened during the night by an attack of the following symptom in the last 12 months: shortness of breath

(5)When you are near animals, feathers, or in a dusty part of the house, do you ever get a feeling of tightness in your chest?

Asthma Questionnaire

Have you had an attack of asthma in the last 12 months?

Did a doctor ever tell you that you have

asthma?

Are you currently taking any medicine (including inhalers, aerosols or tablets) for asthma?

Occupationnal Asthma Questionnaire

(1) Occupational exposure and history(2) General asthma questionnaire (Burney)(3) Symptoms in relation to the workplace(4) Non-occupational exposure related to

common environmental aeroallergens and allergies

(5) Family history of atopy and asthma(6) Life-habits and smoking

Symptoms in relation to the workplace

                When you are at work, do you ever 1. start to feel short of breath or get chest

tightness? 2. start to cough? 3. start to wheeze? 4. related to your work do theses problems

lessen or disappear during the weekend or during holidays?

 

Symptoms in relation to the workplace

Questions related to the presence of eye and nasal symptoms were also included because they often

accompany respiratory symptoms, especially in the case of workplace high-molecular-weight proteinaceous agents

Questionnaire

type of job, work shift and agents that the workers identified as potential causes of symptoms;

the nature of symptoms during working periods, i.e. chest symptoms (cough, sputum, chest tightness,

wheezing, shortness of breath at rest and/or on exertion, change in voice), general symptoms (fever, chills, muscle or joint pain), nasal symptoms (blocked nose, runny nose, sneezing, nasal or throat itching), eye symptoms (itching, runny eyes, redness of the eyes), and skin symptoms (rash, eczema).

Questionnaire

timing of the onset of symptoms in relation to the beginning of the occupation

the relationship between work and respiratory, nasal, conjunctival or skin symptoms asking whether symptoms differed on days at work and away from work

whether there was a specific product causing onset of symptoms

whether there was an improvement in or disappearance of symptoms at weekends and on vacation.

Questionnaire

The temporal pattern of asthmatic symptoms was also addressed (time interval necessary to develop symptoms

after starting work, persistence of symptoms after the work shift and presence of symptoms only on return from work).

In the current study

Besides wheezing, nasal and ocular itching, runny nose was significantly associated with the presence of OA due to

high-molecular-weight agents (HMW). Loss of voice was more prevalent in subjects without OA, suggesting that upper airway dysfunction could be responsible for work-related respiratory symptoms in some subjects.

In the current study

For low-molecular weight agents, no questionnaire item

was found to be significantly predictive of the presence or absence of OA.

(1) LMW agents cause nasoconjunctival symptoms less often than HMW

(2)LMW agents are chemicals that may more easily cause nonspecific irritation of the airways with symptoms in subjects with non-OA, making distinction between OA and work-aggravated asthma more difficult.

(3)LMW agents causing OA often induce late asthmatic reactions that, contrary to immediate reactions, are more difficult to relate temporarily to work.