Lifestyle Factors and Respiratory Diseases Flashcards
Common Cold
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
Being Cold
Scientific opinion dismisses cause-effect
Acute cooling of body surfaces causes reflex vasoconstriction in nose and upper airways, inhibiting respiratory defence
Sleep
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
Vitamin C
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
Echinacea
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
Stress
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
Social Factors
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
Asthma
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)
Psychosocial Factors of asthma
Symptoms exacerbated by stress
Stress causes inflammation of airways and changes in immune response
chronic stress and acute stress contribute to asthma
Lung Cancer
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