Smoking during labour.

Smoking in hospitals is now forbidden. In several hospitals, however, women in labour are allowed to smoke in designated smoking areas. This study assesses whether smoking during labour increases the carboxyhaemoglobin concentrations in maternal and cord blood, taking into account the number of cigarettes smoked during pregnancy, duration of labour and parity. Women were questioned on their smoking behaviour shortly after delivery. A total of 295 mother-infant pairs were included in the study. Of the 94 (31.9%) smokers, 33 smoked during labour at home only and 34 during labour at the hospital. For newborns of smokers, the daily ration of cigarettes smoked by the mother during pregnancy and the number smoked during labour explained respectively 10.4% and 10.8% of the residual variance of carboxyhaemoglobin in cord blood. Smoking during labour significantly increases carboxyhaemoglobin levels. It should be prohibited in hospitals.

Prognostic value of bronchoalveolar lavage lymphocyte count in recently diagnosed pulmonary sarcoidosis.

We prospectively looked at the prognostic value of bronchoalveolar lavage (BAL) lymphocyte count in 98 patients with recently diagnosed (less than 4 months) untreated sarcoidosis. These 50 men and 48 women (mean age, 37.4) were followed up for a period of 6 to 60 months (mean, 25.6), and were clinically evaluated every three to six months with repeated chest roentgenograms and pulmonary function tests. Twenty-four patients required steroid treatment during the study period. The proportion of treated patients was not significantly higher in the group presenting a BAL lymphocyte count less than or equal to 30 percent at diagnosis than in the group with fewer lymphocytes (31.9 and 17.7 percent of total group respectively, p = 0.10). No significant change in TLC, FRC, FVC, FEV1 or DLCO was found at follow-up between the groups with or without an initial high lymphocyte count. In the treated group, BAL lymphocyte percent weakly correlated with the improvement of FEV1 and FVC while on steroid treatment (mean duration: 3.5 months): r = 0.41, p = 0.031 and r = 0.36, p = 0.05 respectively; no correlation was found with lung volumes and DCO. We conclude that BAL lymphocyte count at the time of diagnosis is not a helpful predictor of lung function deterioration in recently diagnosed sarcoidosis and is not very useful in predicting response to treatment.

Time trends in characteristics and outcome of twin pregnancies.

This study describes the evolution in fetal and neonatal mortality rates among twin pairs born in 22 hospitals located in the eastern regions of the province of Quebec in 1976-1978 (n = 776 pairs) and 1982-1985 (n = 712 pairs). It also assesses the contribution of maternal factors, obstetrical care and characteristics of twins in the variation of the risk of death over time. The fetal mortality rate did not improve from 1976-1978 (22.6 per 1000) to 1982-1985 (28.1 per 1000). However, the neonatal mortality rate declined from 44.7 to 34.7 per 1000 liveborn first twins and from 56.8 to 36.1 per 1000 liveborn second twins. For first twins as for second twins, birthweight-specific neonatal mortality rates decreased within birthweight categories under 2500 g. In the second period, 96.9% of twin pregnancies were detected before confinement compared to 59.6% in the earlier period. The proportion of twins delivered by obstetricians, the percentage of twin births occurring in ultraspecialized perinatal units and the frequency of caesarean sections increased markedly. The proportion of preterm births increased over time (34.5% vs 43.1%) whereas the percentage of low birthweight twins decreased but not significantly (54.3% 51.6%). In this study, changes in maternal age, parity, educational level, sex of pairs, qualification of the physician, and level of care available at the hospital of birth, did not account for the decrease in neonatal mortality rates among twins. The increase in the frequency of caesarean sections seemed to explain only a small proportion of the decrease in the neonatal mortality rate among second twins. In the second as well as in the first period, the neonatal mortality rate for twins was six times higher than that for singletons.

[Association between maternal smoking and breast feeding]. / Association entre la consommation maternelle de cigarettes et le mode d'allaitement.

Many factors influence the decision to initiate and continue to breastfeed. Our study evaluates the relation between maternal cigarette smoking and prevalence of breastfeeding. A telephone questionnaire was administered by nurses to mothers of 879 newborns from the Quebec City area approximately two weeks after delivery. Among the 666 babies whose mothers did not smoke, 62.6% were breastfed. This proportion declined to 37.5%, 17.7% and 14.6% among babies whose mothers smoked 1 to 10, 11 to 20 and more than 20 cigarettes per day, respectively. The dose-effect association between the prevalence of breastfeeding and the number of cigarettes smoked daily by the mother persisted after adjustment in a binomial regression model for maternal age, education and home district area. Pregnant women who smoke should be strongly encouraged to quit smoking and to breastfeed their babies.

Diet, mammographic features of breast tissue, and breast cancer risk.

This case-control study was designed to reevaluate the association of the morphology of breast tissue seen on mammograms with breast cancer risk and to assess the relation of diet, especially intake of fat and vitamin A, to the high-risk mammographic images. The cases included 290 patients with newly diagnosed breast cancer who were first treated in Quebec in 1982-1984. The controls included 645 women who participated in the Canadian National Breast Screening Study. Risk of breast cancer was higher among women with the P2 or DY parenchymal pattern (relative risk (RR) = 3.7, 95% confidence interval (Cl) 2.0-7.0) than it was among those with the N1 pattern. Moreover, risk increased regularly with the extent of nodular and homogeneous densities on the mammogram. Relative risk was 5.5 (95% Cl 2.3-13.2) for women in whom 60% or more of the volume of the breast showed either nodular or homogeneous densities compared with women without such densities. Among controls, increase in energy-adjusted saturated fat intake was associated with an increase in extent of high-risk mammographic features. Energy-adjusted polyunsaturated fat or cholesterol intake did not, however, appear to influence the morphology of breast tissue seen on the mammogram. Increasing carotenoid and fiber intakes were associated with a reduction of the extent of densities on the mammogram, but retinol intake seemed to have little or no effect on mammographic features. These data suggest that elevation in saturated fat intake and reduction in carotenoid and fiber intakes may be related to an increase in breast cancer risk through effects of these nutrients on breast tissue morphology.

Comparative efficacy of salbutamol, ipratropium, and cromoglycate in the prevention of bronchospasm induced by exercise and hyperosmolar challenges.

We compared the inhibitory effects of inhaled salbutamol (S), ipratropium (I), and cromoglycate (C) on bronchospasm induced by exercise (EX) or hyperosmolar (HY) saline aerosol in a group of 11 subjects with stable asthma. Each subject had eight tests in a randomized order, four EX and four HY challenges, each preceded by the double-blind inhalation of either a placebo, 200 micrograms of S, 80 micrograms of I, or 4 mg of C. This study demonstrated that the three drugs protected against the two types of challenges in almost all subjects. Although we observed a large interindividual variability in the airway response to the challenges, there was no statistically significant difference in the mean percent protection after HY or EX challenges when these challenges were preceded by S, I, or C (p greater than 0.05). Moreover, for EX- and HY-induced bronchospasm, the mean percent protection afforded by the three medications was in the same order (S greater than I greater than C), although the protective effect against EX-induced was weaker than against HY-induced bronchospasm. This suggests that hyperosmolarity, although it may not be the sole factor involved, plays a role in EX-induced bronchospasm.