Obstructive lung disease does not increase lung cancer mortality among female never-smokers in Hong Kong.
METHODS
High lung cancer mortality is observed among female never-smokers in Hong Kong.


OBJECTIVE
To examine the relationship between obstructive lung disease (chronic obstructive pulmonary disease and/or asthma) and lung cancer mortality by sex and smoking status.


METHODS
A cohort of elderly clients (aged ≥65 years) in a health maintenance programme were followed prospectively through linkage with the territory-wide death registry for causes of death, using identity card number as the unique identifier.


RESULTS
After 516,055 person-years of follow-up, respectively 1297, 872 and 1908 deaths were caused by lung cancer, other tobacco-related malignancies and non-tobacco-related malignancies. In the overall analysis, obstructive lung disease was independently associated with mortality due to lung cancer (aHR 1.86, P < 0.001) after adjustment for potential confounders. However, no association was detected among female never-smokers (HR 0.97, P = 0.909), in sharp contrast with female ever-smokers, male never-smokers and male ever-smokers (HR 1.98, 2.34 and 2.09, respectively, P from 0.047 to <0.001). Consistent results were observed after exclusion of all deaths in the initial 3 years.


CONCLUSIONS
Obstructive lung disease exerted differential effects on lung cancer mortality across different sex and smoking subgroups in this Asian population, with a conspicuous absence of effect among female never-smokers.
TB and Chest Service, Department of Health, Hong Kong, China. cc_leung@dh.gov.hk
C C
CC
Leung
T H
TH
Lam
W-W
WW
Yew
W S
WS
Law
C M
CM
Tam
K C
KC
Chang
S
S
McGhee
S Y
SY
Tam
K F
KF
Chan
D000368:Aged; D044466:Asian People / Q000706:statistics & numerical data; D001249:Asthma / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D006279:Health Maintenance Organizations; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008175:Lung Neoplasms / Q000209:etiology / Q000401:mortality*; D008297:Male; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications*; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D013534:Survival