[Tobacco smoking and risk of hip fracture in men and women. Results from the Hovedstadens Center for Prospective Population Studies]

INTRODUCTION

In the present population-based cohort study, we prospectively determined the influence of current, previous, and cumulative smoking history on the risk of hip fracture in men and women and addressed the issue of possible gender difference in susceptibility to tobacco smoking.

MATERIAL

A total of 13,393 women and 17,379 men, initially examined between 1964 and 1992, were followed up until 1997 for their first admission because of hip fracture.

RESULTS

During follow-up, a total of 1169 hip fractures were identified. After adjustment for potential confounders, female current smokers had a relative risk of hip fracture of 1.36 (1.12-1.65) and male smoked 1.59 (1.04-2.43) relative to those who have never smoked. In both sexes, the relative risk of hip fracture gradually increased with current and accumulated tobacco consumption. A test for interaction between gender and smoking habits was insignificant. Men who stopped smoking for more than five years had a lower risk of hip fracture than men who currently smoked, whereas no such risk reduction was seen in female ex-smokers.

CONCLUSION

Tobacco smoking is an independent risk factor for hip fracture in men and women, and there appears to be no gender differences in the smoking-related risk. Men who stopped smoking for more than five years had lower risk of hip fracture than men who currently smoked, whereas no such risk reduction was seen in female ex-smokers.

[Smoking and life expectancy among Danish men and women]

Studies reporting increased mortality in smokers are abundant, but only few have included large numbers of heavily smoking women. Based on three large Danish population studies we calculated median survival in smokers and never-smokers and compared the impact of smoking in men and women. Seventeen thousand six hundred and sixty-nine men and 13,525 women were followed for up to 30 years for all-cause mortality. During follow-up there were 8644 deaths. Large differences in tobacco-exposure between men and women were found, in particular in older birth-cohorts. Despite a smaller accumulated exposure, the impact smoking had on median survival was similar in men and women. Female inhaling heavy smokers (> or = 15 cig./day) lost 9.4 and inhaling light smokers 7.4 years in comparison with female never-smokers. Corresponding loss of life-expectancy in males was 9.2 years and 6.0 years, respectively. In conclusion, this study shows survival prospects in relation to smoking in both men and women in a way that is easily communicated. The results indicate that women who smoke as much as men run a relatively higher risk in terms of reduced life expectancy.

[Chronic expectoration and risk of death in chronic obstructive lung disease]

We wished to determine whether excess COPD-related mortality in subjects with chronic mucus hypersecretion (CMH) could be explained by proneness to pulmonary infection.

METHODS

14,223 subjects of both sexes were followed for 10-12 years. Deaths with COPD as underlying or contributory cause (n = 214) were included and if death occurred in hospital, hospital records were obtained when possible (n = 101). From information regarding increased or purulent mucus, fever, leucocytosis and chest X-ray during hospital admission, death was classified as caused by pulmonary infection (n = 38), not caused by pulmonary infection (n = 51), or unclassifiable (n = 12).

RESULTS

Of subjects reporting CMH, 54% died from pulmonary infection, whereas that was only the case for 28% of subjects without CMH (p < 0.01). Cox regression-analysis showed a strong inverse relationship between ventilatory function and COPD-related mortality. CMH was an independent predictor of death with pulmonary infection implicated (RR:3.5) but not of death without pulmonary infection (RR:0.9).

CONCLUSION

COPD-patients with CMH are more likely to die from pulmonary infection than COPD-patients without CMH.