Lifestyle Factors and Respiratory Diseases

Question 1

Common Cold

Answer 1

Upper respiratory tract infections account for 50% of acute illnesses
Rhinoviruses account for 30-50% of adult colds
Big economic impact
Incidence: kids 6 colds/year, adults 2/3 colds/year
Exposure does not always = symptoms and illness

Question 2

Being Cold

Answer 2

Scientific opinion dismisses cause-effect

Acute cooling of body surfaces causes reflex vasoconstriction in nose and upper airways, inhibiting respiratory defence

Question 3

Sleep

Answer 3

A positive, explanatory ‘host factor’
Important predictor of immunity
Link between sleep duration and development of a cold; and sleep efficiency and development of a cold

Question 4

Vitamin C

Answer 4

Review of placebo-controlled trials of vit C megadose (200mg)
Recommended daily intake = 40mg
Prophylaxis & cold incidence: 24 trial comparisons, no sig reduction 0.97; 5 trial comparison of runners, skiers… sig reduction 0.48
Prophylaxis & cold duration: 31 trials, sig reduction adults RR = 0.92, children RR = 0.86
Therapy & Cold Duration: 7 trials, no sig difference
Megadosing won’t prevent cold, but may shorten it

Question 5

Echinacea

Answer 5

Review of placebo controlled trials
Prophylaxis and Cold Incidence: 12 trials, no sig effect, 10-20% reduction in risk.
Prophylaxis & Cold Duration: 7 trials, no sig effect
Prevention trial drop out rates higher for echinacea than for placebo groups
Different echinacea products differ

Question 6

Stress

Answer 6

Chronic stress increases risk of cold
Assessment of duration, types of stressors, current infection, followed by introduction of cold viruses
Risk also related to smoking, lack of exercise, poor sleep efficiency, increased alcohol
Sig association between smoking and chronic stress

Question 7

Social Factors

Answer 7

Pre-exposure measures and follow up to detect disease/symptoms
Increased subjective SES associated with decreased risk of colds
Poorer sleep and health behaviours among lower SES may mediate association

Question 8

Asthma

Answer 8

300 million people worldwide experience asthma - large economic costs
People with asthma are expected to monitor symptoms and make use of inhaler appropriately
Psychological interventions are effective (self-management education)

Question 9

Psychosocial Factors of asthma

Answer 9

Symptoms exacerbated by stress
Stress causes inflammation of airways and changes in immune response
chronic stress and acute stress contribute to asthma

Question 10

Lung Cancer

Answer 10

7% of male deaths, 4% of female
Dose response effect linking to number of cigarettes, depth of inhalation etc, to increased risk of cancer
90% of lung cancers could be avoided if smokers quit
Other causes: asbestos, radon gas, radiation
Smoking is more common among lower SES groups