Mammography utilization in Canadian women aged 50 to 69: identification of factors that predict initiation and adherence.

OBJECTIVE: To identify factors that predict initiation of mammography and adherence with biennial screening among Canadian women aged 50-69 years. METHODS: Using data from a longitudinal panel of Canadian women interviewed in the National Population Health Survey (NPHS) in 1994/95 and 2 and 4 years later, we estimated the relative risks (RR) of mammography initiation and adherence according to socio-demographic, health and lifestyle characteristics. RESULTS: Among 505 women with no history of mammography use at baseline, 23.0% and 41.4% initiated mammography by 2 and 4 years, respectively. Urban residence (RR = 2.85) was most strongly associated with initiation by 2 years; younger age (50-54) and lower education also predicted initiation by 2 years. Younger age, birthplace outside Canada, and having a recent (< 2 years) blood pressure check were associated with initiation by 4 years. Among 873 women reporting a recent (< 2 years) mammogram at baseline, 88.7% also reported a recent mammogram within 2 years while 73.0% reported one at both the 2- and 4-year follow-up. Being a non-smoker was the strongest predictor of maintaining adherence both at the 2- (RR = 1.18) and the 4-year (RR = 1.37) follow-up. INTERPRETATION: Previously identified underserved groups of Canadian women (e.g., those with lower educational levels or born outside of Canada) were most likely to initiate mammography. Approximately 1 in 6 women aged 50 to 69 years remained never-users during follow-up, and fewer than half reported recent mammograms at all three survey cycles, suggesting the need to reinforce regular screening participation.

Inconsistent self-reported mammography history: findings from the National Population Health Survey longitudinal cohort.

BACKGROUND: Self-reported information has commonly been used to monitor mammography utilization across populations and time periods. However, longitudinal investigations regarding the prevalence and determinants of inconsistent responses over time and the impact of such responses on population screening estimates are lacking. METHODS: Based on longitudinal panel data for a representative cohort of Canadian women aged 40+ years (n = 3,537) assessed in the 1994-95 (baseline) and 1996-97 (follow-up) National Population Health Survey (NPHS), we examined the prevalence of inconsistent self-reports of mammography utilization. Logistic regression models were used to estimate the associations between women's baseline sociodemographic and health characteristics and 2 types of inconsistent responses: (i) baseline reports of ever use which were subsequently contradicted by follow-up reports of never use; and (ii) baseline reports of never use which were contradicted by follow-up reports of use prior to 1994-95. RESULTS: Among women who reported having a mammogram at baseline, 5.9% (95% confidence interval (CI): 4.6-7.3%) reported at follow-up that they had never had one. Multivariate logistic regression analyses showed that women with such inconsistent responses were more often outside target age groups, from low income households and less likely to report hormone replacement therapy and Pap smear use. Among women reporting never use at baseline and ever use at follow-up, 17.4% (95%CI: 11.7-23.1%) reported their most recent mammogram as occurring prior to 1994-95 (baseline) and such responses were more common among women aged 70+ years and those in poorer health. CONCLUSIONS: Women with inconsistent responses of type (i), i.e., ever users at baseline but never users at follow-up, appeared to exhibit characteristics typical of never users of mammography screening. Although limited by sample size, our preliminary analyses suggest that type (ii) responses are more likely to be the result of recall bias due to competing morbidity and age. Inconsistent responses, if removed from the analyses, may be a greater source of loss to follow-up than deaths/institutionalization or item non-response.

Report of the 2003 pan-Canadian forum on cervical cancer prevention and control.

OBJECTIVE: To develop evidence-based consensus recommendations on the delivery of cervical cancer screening, human papillomavirus (HPV) education, HPV testing, and the optimal tool for cervical cytology within the Canadian health system. PARTICIPANTS: Leading up to a forum held in Ottawa on November 21 and 22, 2003, 254 registrants reviewed position papers through a Web-based discussion group. Experts in program management, clinical practice, epidemiology, public health, economics, and women's health, representing 48 organizations, then participated in the 2-day forum to develop consensus recommendations. EVIDENCE: Writing groups prepared position papers on optimal methods for cervical cytology; education concerning HPV; HPV testing in primary screening; HPV testing as a triage tool in cytopathology; and delivery mechanisms for cervical screening. Systematic reviews were the primary source of evidence supplemented by literature searches. CONSENSUS PROCESS: Feedback from Web-based discussions was incorporated into consecutive drafts of position papers. At the forum, recommendations and supporting evidence were presented, further debated in small-group sessions, and discussed in a plenary session. Despite divergent professional mandates and opinions, consensus was achieved on 15 recommendations across all areas. Final recommendations were posted to the Web for further input and circulated for written consensus by participants. CONCLUSIONS: The recommendations cover the use of new evidence and technologies in cervical cancer prevention in Canada and provide a framework for provision of HPV education, planning the implementation of new cervical screening technologies in Canada, the development of evaluation plans, and new research areas.

Prevalence, awareness, treatment, and control of hypertension among Canadian adults with diabetes, 2007 to 2009.

BACKGROUND: Prior national surveys suggested that treatment and control of hypertension were poor in individuals with diabetes. Using measured blood pressures, we estimated prevalence, awareness, treatment, and control of hypertension between 2007 and 2009 among Canadians with diabetes and sought to determine whether a treatment gap still exists for individuals with diabetes. METHODS: Using data from cycle 1 of the Canadian Health Measures Survey, estimates of hypertension prevalence, awareness, treatment, and control were described and compared between individuals with and without self-reported diabetes. RESULTS: Three-quarters of individuals reporting diabetes also had hypertension; of these, 89% (95% confidence interval [CI], 80%-98%) were aware, 88% (95% CI, 81%-94%) were treated, and 56% (95% CI, 45%-66%) were controlled to < 130/80 mm Hg. Among those treated with pharmacotherapy, 39% (95% CI, 31%-48%) were using monotherapy, 29% (95% CI, 18%-40%) were taking 2 medications, and 31% (95% CI, 22%-39%) were taking 3 or more medications; control to < 130/80 mm Hg was achieved by 63% (95% CI, 53%-74%). Among those treated, individuals with diabetes were significantly less likely to be treated to their recommended target (< 130/80 mm Hg) compared with individuals without diabetes (< 140/90 mm Hg; odds ratio(adjusted) 0.3; 95% CI, 0.2-0.6). CONCLUSIONS: Hypertension treatment and control among people with diabetes have improved in Canada during the past 2 decades. Nonetheless, nearly half of people with diabetes are above the treatment target. Health care professionals should continue to increase their efforts in supporting patients with diabetes in achieving blood pressure control, with emphasis on lifestyle management and pharmacotherapy.

Prevalence of, and barriers to, preventive lifestyle behaviors in hypertension (from a national survey of Canadians with hypertension).

Patients with hypertension are advised to lower their blood pressure to <140/90 mm Hg through sustained lifestyle modification and/or pharmacotherapy. To describe the use of lifestyle changes for blood pressure control and to identify the barriers to these behaviors, the data from 6,142 Canadians with hypertension who responded to the 2009 Survey on Living With Chronic Diseases in Canada were analyzed. Most Canadians with diagnosed hypertension reported limiting salt consumption (89%), having changed the types of food they eat (89%), engaging in physical activity (80%), trying to control or lose weight if overweight (77%), quitting smoking if currently smoking (78%), and reducing alcohol intake if currently drinking more than the recommended levels (57%) at least some of the time to control their blood pressure. Men, those aged 20 to 44 years, and those with lower educational attainment and lower income were, in general, less likely to report engaging in lifestyle behaviors for blood pressure control. A low desire, interest, or awareness were commonly reported barriers to salt restriction, changes in diet, weight loss, smoking cessation, and alcohol reduction. In contrast, the most common barrier to engaging in physical activity to regulate blood pressure was the self-reported challenge of managing a coexisting physical condition or time constraints. In conclusion, programs and interventions to improve the adherence to lifestyle changes to treat hypertension may need to consider the identified barriers to lifestyle behaviors in their design.

Home blood pressure monitoring among Canadian adults with hypertension: results from the 2009 Survey on Living with Chronic Diseases in Canada.

BACKGROUND: Canadians with hypertension are recommended to use home blood pressure monitoring (HBPM) on a regular basis. OBJECTIVES: To characterize the use of HBPM among Canadian adults with hypertension. METHODS: Respondents to the 2009 Survey on Living with Chronic Diseases in Canada who reported diagnosis of hypertension by a health professional (n=6142) were asked about blood pressure monitoring practices, sociodemographic characteristics, management of hypertension and blood pressure control. RESULTS: Among Canadian adults with hypertension, 45.9% (95% CI 43.5% to 48.3%) monitor their own blood pressure at home, 29.7% (95% CI 41.1% to 46.3%) receive health professional instruction and 35.9% (95% CI 33.5% to 38.4%) share the results with their health professional. However, fewer than one in six Canadian adults diagnosed with hypertension monitor their own blood pressure at home regularly, with health professional instruction, and communicate results to a health professional. Regular HBPM was more likely among older adults (45 years of age and older); individuals who believed they had a plan for how to control their blood pressure; and those who had been shown how to perform HBPM by a health professional - with the latter factor most strongly associated with regular HBPM (prevalence rate ratio 2.8; 95% CI 2.4 to 3.4). CONCLUSIONS: Although many Canadians with hypertension measure their blood pressure between health care professional visits, a minority do so according to current recommendations. More effective knowledge translation strategies are required to support self-management of hypertension through home measurement of blood pressure.

The distribution and predictive validity of the stages of change for mammography adoption among Canadian women.

OBJECTIVE: To examine the predictive validity of the transtheoretical model (TTM) stages of change for mammography participation in Canadian women. METHOD: We examined the association between baseline TTM stage of mammography adoption and subsequent mammography participation in a representative sample of 3,125 Canadian women aged 40 and older from the longitudinal Canadian National Population Health Survey. RESULTS: The likelihood of having a mammogram at follow-up (1998/1999) increased with progressive stages of change at baseline (1996/1997) even after adjusting for potential confounders. Relative to women in maintenance, women in precontemplation, relapse, contemplation, relapse risk, and action were significantly less likely to report a recent mammogram during follow-up (adjusted RR of 0.41, 0.50, 0.63, 0.75, and 0.92, respectively; P(trend) < 0.01). This pattern held for women within and outside of the 50-69 target age range, and for urban and to a lesser degree rural-dwelling women. CONCLUSION: Our findings support the predictive validity of the TTM stages of mammography adoption construct and the inclusion of both relapse and relapse risk categories to improve the sensitivity of the predictive model. Interventions to promote the eventual maintenance of mammography screening should also benefit from further research that aims to understand the variables that promote progressive movement through the stages.

The influence of breast self-examination on subsequent mammography participation.

OBJECTIVES: We evaluated whether breast self-examination (BSE) influences subsequent mammography participation. METHODS: We evaluated associations between BSE and subsequent mammography participation, adjusting for baseline screening behaviors and sociodemographic, health, and lifestyle characteristics, among women aged 40 years and older using data from the longitudinal Canadian National Population Health Survey. RESULTS: Regular performance of BSE at baseline was not associated with receipt of a recent mammogram at follow-up among all women (adjusted odds ratio [OR]=1.01; 95% confidence interval [CI]= 0.75, 1.35) or with mammography uptake among the subgroup of women reporting never use at baseline (adjusted OR=0.78; 95% CI=0.50, 1.22). CONCLUSIONS: The lack of association between performance of BSE and subsequent mammography participation suggests that not recommending BSE is unlikely to influence mammography participation.