Effectiveness of a single dose of acellular pertussis vaccine to prevent pertussis in children primed with pertussis whole cell vaccine.

We estimated the protection given by one booster dose of acellular pertussis vaccine (aP) given at 18 months or before school entry to children already primed with whole cell vaccine (wP). Case-control studies were conducted in these two age groups. In children who received or were eligible to receive their 18 months booster, the risk of pertussis was 1.4 and 3.6 times higher for those with 4 and 3 wP, respectively, compared to those with 3 wP + 1 aP. In 5 and 6 yr old children, the risk of pertussis among the subjects with 5 and 4 wP, was 1.4 and 2.1 times higher respectively than in those who received 4 wP + 1 aP. A single dose of aP increased the protection against pertussis and this protection was greater than that obtained with a wP booster.

Morbidity of pertussis in adolescents and adults.

The effect of age on the clinical presentation of pertussis was assessed in 664 adolescent and adult cases. Complications were more frequent in adults than in adolescents (28% vs. 16%). Pneumonia occurred in 2% of patients <30 years old but in 5%-9% of older patients. Urinary incontinence occurred in 34% of women >/=50 years old. Duration of cough, risk of sinusitis, and number of nights with disturbed sleep increased with smoking and asthma. The secondary attack rate in other household members >/=12 years was 11%. Pertussis in secondary case patients was less severe than in index case patients but presented with classic symptoms. The main source of infection in adolescents was schoolmates or friends; in adults it was workplace or their children. Teachers and health care workers had a greater risk of pertussis than did the general population. The burden of disease appears to increase with age, with smoking, and with asthma.

Dietary fat and prostate cancer survival.

OBJECTIVES: Relationships between dietary factors and the incidence of prostate cancer have emerged from epidemiologic and laboratory studies, but there are no published data on the relationship between diet and disease progression among prostate cancer patients. We studied the association between dietary fat intake and prostate cancer survival. METHODS: We prospectively followed 384 men diagnosed with prostate cancer between 1990 and 1992 in the Quebec City area. On average 3 months following diagnosis, trained nutritionists interviewed the men on their usual diet using a diet history questionnaire. Deaths during follow-up were documented through record linkage with the provincial mortality file and review of hospital records. Cox proportional hazard models were used to estimate the relative risk of dying from prostate cancer associated with terciles of fat intake, expressed as percent of dietary energy, while controlling for prognostic factors and total energy. RESULTS: The median duration of follow-up was 5.2 years. During the follow-up period 32 patients died of prostate cancer and 39 died of other causes. After controlling for grade, clinical stage, initial treatment, age and total energy intake, we found that saturated fat consumption was significantly associated with disease-specific survival (two-sided p-value = 0.008). Compared to men in the lower tercile of saturated fat, those in the upper tercile had three times the risk of dying from prostate cancer (relative risk = 3.1, 95% confidence interval: 1.3-7.7). CONCLUSIONS: Our findings suggest that saturated fat is related to disease-specific survival and that, if this relation is causal, a moderate reduction of its intake might reduce the risk of dying from prostate cancer.

Dietary fat and prostate cancer progression and survival.

BACKGROUND: The association between dietary factors and the occurrence of prostate cancer has been studied extensively, but there is, as yet, no published study on the relationship between diet and disease progression among prostate cancer patients. We studied the association between dietary fat intake and prostate cancer survival. METHODS: We prospectively followed 384 men diagnosed with prostate cancer between 1990 and 1992 in the Quebec City area who participated in a case-control study of diet in relation to prostate cancer occurrence. Trained nutritionists interviewed the men on their usual diet using a diet history questionnaire. Deaths in the follow-up were documented through record linkage with the provincial mortality file and review of hospital records. The cause of death was taken as written on the death certificate. Cox proportional hazards models were used to estimate the relative risk of dying from prostate cancer associated with terciles of fat intake, expressed as percent of dietary energy, while controlling for prognostic factors and total energy. RESULTS: The median duration of follow-up was 5.2 years. During the follow-up period, 32 patients died of prostate cancer and 39 died of other causes. The 5-year disease-specific survival was 91%. After controlling for grade, clinical stage, initial treatment, age and total energy intake, we found that saturated fat consumption was significantly associated with disease-specific survival (p = 0.008). Compared to men in the lower tercile of saturated fat, those in the upper tercile had three times the risk of dying from prostate cancer (hazards ratio 3.13, 95% confidence interval 1.28-7.67). CONCLUSION: Our findings suggest that, if saturated fat is causally related to disease-specific survival, a moderate reduction of its intake below 10% of energy should reduce the risk of dying from prostate cancer. This dietary goal is already recommended for health promotion and primary prevention of heart disease and cancer.