Short-term impact of a neighbourhood-based intervention on mental health and self-rated health in Hamilton, Ontario, Canada.

The Hamilton Neighbourhoods Study aimed to measure the short-term impact of a neighbourhood-based intervention known as the City of Hamilton's Neighbourhood Action Strategy on health and neighbourhood outcomes. A quasi-experimental study with 881 intervention participants across six targeted neighbourhoods and 173 control participants was conducted to investigate changes in self-rated health and mental health from baseline to follow-up. There was evidence of small improvements in mental health in two neighbourhoods, but there was no change in self-rated health. Place-based interventions aimed at high poverty neighbourhoods may have only modest impacts on health in the short-term.

Benzodiazepines and risk for breast cancer.

PURPOSE: The study aim is to evaluate benzodiazepine use and risk for breast cancer in Ontario, Canada, by using a population-based case-control study design. METHODS: Cases were a random sample of women aged 25 to 74 years identified through the Ontario Cancer Registry and diagnosed with breast cancer between 1996 and 1998 (n = 3133). Controls were an age-matched random sample of women (n = 3062). Cases and controls completed a self-administered questionnaire that included questions about their past use of benzodiazepines (defined as daily use for at least 2 months) and potential confounders. Individual classes of benzodiazepines also were evaluated. Multivariate logistic regression analysis was conducted, and odds ratios (ORs) and 95% confidence intervals (CIs) were estimated. RESULTS: Compared with nonusers, ever use of benzodiazepines was not significantly associated with risk for breast cancer (OR, 1.06; 95% CI, 0.88-1.27). No apparent trends were observed for duration of use, time since first use, or time since last use. Estimates according to individual classes of benzodiazepines, including diazepam, lorazepam, and chlordiazepoxide, also were not statistically significant. CONCLUSION: Our data show no association between benzodiazepine use and breast cancer risk. Results confirm findings from previous studies that diazepam use does not increase the risk for breast cancer and also suggest no association with the use of other benzodiazepine compounds.

Performance measures from 10 years of breast screening in the Ontario Breast Screening Program, 1990/91 to 2000.

Performance measures for the Ontario Breast Screening Program (OBSP) by age group, time period and screening modality from 10 years of breast screening were evaluated. Data were available from routine information collected on 283,962 women aged 50 to 69 screened at 73 screening centres between 1 July 1990 and 31 December 2000. Although, initially, participation in the OBSP was low, this rate increased over time and the majority of women screened returned for subsequent screening. Abnormal call rates increased slightly over the time period, were higher in women aged 50 to 59, and for women with mammographic abnormalities. Detection rates of invasive cancer were higher and prognostic features of cancers were better for women age 60 to 69, and those referred by mammography. Along with the prognostic features of cancers, the benign to malignant surgical ratio and diagnostic interval improved over the time periods and for women aged 60 to 69. Greater proportions of women had shorter diagnostic intervals and were more likely to have a diagnosis of breast cancer after surgery if they were referred by both clinical breast examination and mammography. Although some enhancements of the programme are necessary, the OBSP met or exceeded Canadian targets for most performance measures.

Accuracy of breast screening among women with and without a family history of breast and/or ovarian cancer.

OBJECTIVES: To compare interval cancer rates, sensitivity and specificity of breast cancer screening between women with moderate or strong family history and women without a family history. METHODS: From 1996 to 1997, 115,460 women aged 50 to 69 screened by the Ontario Breast Screening Program, offering eligible women screening with mammography and clinical breast examination, were examined. Women were followed for up to 12 months after their screening examination. Family history definitions were based on the number of affected first degree relatives and their ages at diagnosis. Multivariate analysis was conducted to adjust for potential confounding variables. RESULTS: Interval cancer rates increased across family history groups and were greatest in women with a strong family history. The rate ratio (RR) for interval cancer rate in women with a strong family history compared to women without a family history approached significance (RR=2.28, 95% confidence interval (CI) 0.97-5.34), while for women with a moderate family history it did not (RR=1.37, 95% CI 0.62-3.04). A slightly but not significantly lower sensitivity was observed in women with a strong family history compared to women without a family history. There was little variation in specificity across family history groups. CONCLUSIONS: Screening was able to detect a large proportion of invasive breast cancers in women with a family history, indicating their potential to benefit from regular breast cancer screening. However, due to increased interval cancer rates, screening with one-year intervals may be important even in an older population of women with a family history.

Effect of screening result on waiting times to assessment and breast cancer diagnosis: results from the Ontario Breast Screening Program.

BACKGROUND: The effect of severity of screening result on delays to diagnosis has primarily been examined for mammographic abnormalities. This study will examine delays to assessment and diagnosis for women with an abnormal mammogram compared to women with an abnormal clinical breast examination (CBE) or abnormal CBE and mammogram. METHODS: Using data routinely collected by Ontario Breast Screening Program (OBSP), 12,675 women aged 50 to 69 with an abnormal screening result between January 1, 2000 and December 31, 2000 were followed prospectively to the completion of their assessment process. Median waiting times from abnormal screen to first assessment procedure and diagnosis were compared by modality of referral and among women with a breast cancer diagnosis by prognostic features. RESULTS: The median waiting time to first assessment and to diagnosis was significantly longer for women with only a clinical abnormality compared to women with a mammographic abnormality. In addition, women diagnosed with cancers of larger size had longer delays when the abnormality was detected only clinically. However, women referred by both modalities had significantly shorter waiting times to first assessment procedure and to diagnosis of poor prognosis cancers compared to women referred by mammography alone. INTERPRETATION: Women with an abnormal CBE and mammogram are assessed more promptly and have shorter diagnostic times. However, women with only a CBE abnormality had delays to diagnosis as a result of longer waiting times to first assessment procedure. Integration of the OBSP with assessment centres should improve times to diagnosis irrespective of modality of referral.