Prescribing patterns of glucosamine in an older population: a national cohort study

BACKGROUND

Glucosamine is commonly prescribed as a disease modulating agent in osteoarthritis. However, the evidence to date suggests that it has a limited impact on the clinical symptoms of the disease including joint pain, radiological progression, function and quality of life. The aim of this study was to examine the prescribing patterns of glucosamine from 2002-2011 in an elderly Irish national population cohort using data from the Health Service Executive Primary Care Reimbursement (HSE-PCRS) General medical services (GMS) Scheme.

METHODS

Patients aged ≥ 70 years on the HSE-PCRS pharmacy claims database between January 2002 and December 2011 were included. ATC code M01AX05 (glucosamine) was extracted. Prevalence rates per 1000 eligible population with 95% confidence intervals were calculated for all years and age groups (70-74 years, ≥75 years). A negative binomial regression analysis was used to determine longitudinal usage trends and compare prevalence rates across years, sex and age groups.

RESULTS

The annual patient rate of glucosamine prescribing increased significantly from 13.0/1000 eligible population (95% CI 12.6-13.4) in 2002 to 68.7/1000 population (95% CI 67.8-69.5) in 2009 before decreasing to 62.4/1000 population (95% CI 61.6-63.2) in 2011. The rate of prescribing of glucosamine varied with sex, with women receiving significantly more prescriptions than men. The cost of glucosamine also increased from 2002-2008. In 2008 total expenditure reached a high of €4.6 million before decreasing to €2.6 million in 2011.

CONCLUSION

The national trend in prescribing of glucosamine increased significantly from 2002 to 2009 before decreasing in 2010 and 2011, in keeping with current international guidelines. There is a need for awareness among healthcare professionals and patients alike of the best available evidence to inform decision making relating to the prescription and consumption of such supplements.

An observational study examining the effect of comorbidity on the rates of persistence and adherence to newly initiated oral anti-hyperglycaemic agents

PURPOSE

To examine whether the type of comorbid condition affects medication persistence and adherence in patients initiating oral anti-hyperglycaemic (OAH) therapy.

METHODS

The Irish Health Services Executive pharmacy claims database was used to identify a cohort of incident OAH therapy users (anatomical therapeutic chemical A10B), ≥25 years, between June 2009 and December 2010. Persistence and adherence were examined at 6 and 12 months post-therapy initiation. Comorbidity was ascertained using modified versions of the RxRisk and RxRisk-V indices and classified as either concordant or discordant with diabetes. Adjusted odds ratios (ORs) and 95% confidence intervals (95%CIs) were determined in relation to comorbidity using logistic regression analysis, adjusting for age, gender and type of OAH prescribed.

RESULTS

In the study cohort (n = 21 280), persistence was 74.0% and 62.6% and adherence was 70.0% and 66.7% for all OAHs at 6 and 12 months, respectively. Patients with only concordant comorbidity were significantly more likely to be persistent at 6 (OR 1.45, 95%CI 1.28, 1.65) and 12 months (OR 1.22, 95%CI 1.09, 1.38). Patients with only discordant comorbidity were significantly less likely to be persistent at 6 (OR 0.40, 95%CI 0.35, 0.46) and 12 months (OR 0.43 95%CI 0.38, 0.50) (p < 0.0001). Results were similar for adherence.

CONCLUSION

The study suggests that the persistence and adherence of OAH therapy in incident users are affected by the type of comorbidity present; this may help in identifying effective interventions aimed at optimising medication use.

Predictors and moderators of response to internet-delivered Interpersonal Psychotherapy and Cognitive Behavior Therapy for depression

BACKGROUND

By identifying which predictors and moderators lead to beneficial outcomes, accurate selection of the best initial treatment will have significant benefits for depressed individuals.

METHOD

An automated, fully self-guided randomized controlled internet-delivered noninferiority trial was conducted comparing two new interventions (Interpersonal Psychotherapy [IPT; n=620] and Cognitive Behavioral Therapy [CBT; n=610]) to an active control intervention (MoodGYM; n=613) over a period of 4 weeks to spontaneous visitors of an internet-delivered therapy website (e-couch). A range of putative predictors and moderators (socio-demographic characteristics [age, gender, marital status, education level], clinical characteristics [depression/anxiety symptoms, disability, quality of life, medication use], skills [mastery and dysfunctional attitudes] and treatment preference) were assessed using internet-delivered self-report measures at baseline and immediately following treatment and at six months follow-up. Analyses were conducted using Mixed Model Repeated Measures (MMRM).

RESULTS

Female gender, lower mastery and lower dysfunctional attitudes predicted better outcome at post-test and/or follow-up regardless of intervention. No overall differential effects for condition on depression as a function of outcome were found. However, based on time-specific estimates, a significant interaction effect of age was found. For younger people, internet-delivered IPT may be the preferred treatment choice, whereas older participants derive more benefits from internet-delivered CBT programs.

LIMITATIONS

Although the sample of participants was large, power to detect moderator effects was still lacking.

CONCLUSIONS

Different e-mental health programs may be more beneficial for specific age groups. The findings raise important possibilities for increasing depression treatment effectiveness and improving clinical practice guidelines for depression treatment of different age groups.

Statins and risk of treated incident diabetes in a primary care population

AIMS

(i) To examine the incidence of new onset treated diabetes in patients treated with different types of statins and (ii) the relationship between the duration and dose of statins and the subsequent development of new onset treated diabetes.

METHODS

A retrospective cohort study was performed using the Irish Health Services Executive Primary Care Reimbursement Services national pharmacy claims database. Individuals who received any medicines were identified from January 2001 to January 2009 (n = 1 235 671). Patients newly treated with statins from 1 January 2002 to 31 December 2007 were identified (n = 239 628). Cases were identified as individuals newly treated with antidiabetic medication (n = 38 503). Adjusted hazards ratios (HR) with 95% confidence intervals (CI) were calculated to examine the association between statins (any vs. none) and time to new onset treated diabetes using Cox proportional hazard regression. The dose and duration response relationship between statins and new onset treated diabetes was examined using restricted spline functions to assess the linearity of the relationship.

RESULTS

Statin use was associated with an increased risk of new onset treated diabetes (HR = 1.18, 95% CI 1.15, 1.22). Increased risk of new onset treated diabetes was found with rosuvastatin (HR = 1.41, 95% CI 1.31, 1.52), atorvastatin (HR = 1.23, 95% CI 1.19, 1.27) and simvastatin (HR = 1.15, 95% CI 1.05, 1.25). There were statistically significant overall dose and duration effects for all statins, excepting fluvastatin, which only demonstrated a duration effect.

CONCLUSION

An increased risk of new onset treated diabetes was found in those treated with statins showing significant duration and dose effect. Further study is required to confirm this association.

Prescribing of antidiabetic therapies in Ireland: 10-year trends 2003-2012

BACKGROUND

Over the last decade there have been significant changes in the prescribing of antidiabetic therapies. It is of interest to know about these trends and variations in the Irish population so that future prescribing patterns can be estimated.

AIMS

To examine the trends in prescribed antidiabetic treatments, including variations across age, gender, socioeconomic status and regions in the Irish population over the last 10 years.

METHODS

The Irish national pharmacy claims database was used to identify patients ≥ 16 years dispensed antidiabetic agents (oral or insulin) from January 2003 to December 2012 through the two main community drug schemes for diabetes. The rate of prescribing per 1,000 population was calculated. Logistic regression was used to examine variations in prescribing in patients with diabetes.

RESULTS

There was a significant increase in the prescribing of fast and long-acting insulin analogues with a rapid decline in the prescribing of human insulin (p < 0.0001). Increased prescribing of metformin, incretin modulators and fixed oral combination agents was observed (p < 0.0001). Females and older aged patients were more likely to be prescribed human insulin than other insulins. Metformin was less likely while sulphonylureas were more likely to be prescribed in older than younger aged patients. Socioeconomic differences were observed in increased prescribing of the newer and more expensive antidiabetic agents in the non-means tested scheme. Regional variations were observed in the prescribing of both insulin and oral antidiabetic agents.

CONCLUSION

There has been an increase over time in the prescribing of both insulin and oral antidiabetic agents in the Irish population with increasing uptake of newer antidiabetic agents. This has implications for projecting future uptake and expenditure of these agents given the rising level of diabetes in the population.

Impact of two different health systems on the burden of type 2 diabetes

OBJECTIVES

Health policy directs the management of patients with chronic disease in a country, but evaluating nationwide policies is difficult, not least because of the absence of suitable comparators. This paper examines the management of patients with type 2 diabetes in two demographically comparable populations with different health care systems to see if this represents a viable approach to evaluation.

METHODS

A secondary analysis of centralized prescribing databases for 2010 was undertaken to compare the levels and costs of care of patients with type 2 diabetes in Northern Ireland's National Health Service (NHS) (NI, n = 1.8 million) which has structured care, financial incentives related to diabetes care and an emphasis on generic prescribing, with that of the Republic of Ireland (ROI, n = 4.3 million) where management of diabetes care is guided solely by clinical and other guidelines.

RESULTS

The prevalence of treated type 2 diabetes was 3.59% in NI and 3.09% in ROI, but there were similar and high levels of prescribing of secondary cardiovascular medications. Medication costs per person for anti-diabetic, anti-obesity and cardiovascular medication were 46% higher in ROI than NI, due to differences in levels of generic prescribing.

CONCLUSIONS

These different health care systems appear to be producing similar levels of care for patients with type 2 diabetes, although at different levels of cost. The findings question the need for financial incentives in NI and highlight the large cost savings potentially accruing from a greater shift to generic prescribing in ROI. Cross-country comparison, though not without difficulties, may prove a useful adjunct to within-country analysis of policy impact.

Agreement between patient interview data on prescription medication use and pharmacy records in those aged older than 50 years varied by therapeutic group and reporting of indicated health conditions

OBJECTIVES

To estimate the agreement between interview-ascertained medication use and pharmacy records among the population aged older than 50 years, and to identify patient-level predictors of discordance.

STUDY DESIGN AND SETTING

The Irish Longitudinal study on Ageing is representative of community-dwelling adults aged 50 years and older in Ireland. Interview-ascertained medication data from 2,621 participants were linked to pharmacy dispensing records. The kappa statistics measured the agreement between the two sources for 19 therapeutic classes. Logistic regression assessed the effect of patient-level characteristics on survey under- and overreporting of regularly dispensed medications.

RESULTS

Agreement was good or very good (κ=0.64-0.86) for 15 medication classes, and moderate or poor for antiinflammatory and antirheumatic products (κ=0.54), analgesics (κ=0.50), psycholeptics (κ=0.59), and ophthalmologicals (κ=0.37). Not reporting an indicated health condition, less frequent dispensing, older age, and more medications regularly dispensed were associated with survey underreporting, but results varied by therapeutic class. Memory and cognition were not associated with discordance.

CONCLUSION

Ascertaining medication use via patient interview seems a valid method for most medication classes and also captures nonprescription and supplement use. However, medications applied topically and as needed may be underreported. The source of medication data should be carefully considered when performing pharmacoepidemiological studies.

A cohort study of digoxin exposure and mortality in men with prostate cancer

OBJECTIVE

To examine the association between digoxin exposure and mortality in men with prostate cancer using linked Irish National Cancer Registry and pharmacy claims data.

PATIENTS AND METHODS

Prostate cancer cases were identified from the database and digoxin exposure at prostate cancer diagnosis was identified from prescription claims. Digoxin users were matched to non-users using a propensity score to identify men with similar cardiovascular comorbidity. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for the association between digoxin exposure and all-cause and prostate cancer-specific mortality (PCSM). Analyses were repeated in the propensity score-matched cohort. Effect modification of treatment with radiation or androgen-deprivation therapy by digoxin exposure was also assessed.

RESULTS

In all, 5732 men with a prostate cancer diagnosis (2001-2006) were identified (digoxin exposed, 391). The median follow-up was 4.3 years. Digoxin exposure was associated with a small non-significant increase in PCSM in the full cohort (HR 1.13, 95% CI 0.91, 1.42) and the propensity. score-matched cohort (HR 1.17, 95% CI 0.88, 1.57). Adjusted HRs for all-cause mortality were increased for digoxin exposed men (HR 1.24, 95% CI 1.07, 1.43). Interactions with treatments received were not significant.

CONCLUSIONS

These results suggest digoxin exposure is not associated with reduced PCSM. Further investigation of other cardiac glycosides that have shown anti-cancer potential may be warranted.

Modelling obesity outcomes: reducing obesity risk in adulthood may have greater impact than reducing obesity prevalence in childhood

A common policy response to the rise in obesity prevalence is to undertake interventions in childhood, but it is an open question whether this is more effective than reducing the risk of becoming obese during adulthood. In this paper, we model the effect on health outcomes of (i) reducing the prevalence of obesity when entering adulthood; (ii) reducing the risk of becoming obese throughout adult life; and (iii) combinations of both approaches. We found that, while all approaches reduce the prevalence of chronic diseases and improve life expectancy, a given percentage reduction in obesity prevalence achieved during childhood had a smaller effect than the same percentage reduction in the risk of becoming obese applied throughout adulthood. A small increase in the probability of becoming obese during adulthood offsets a substantial reduction in prevalence of overweight/obesity achieved during childhood, with the gains from a 50% reduction in child obesity prevalence offset by a 10% increase in the probability of becoming obese in adulthood. We conclude that both policy approaches can improve the health profile throughout the life course of a cohort, but they are not equivalent, and a large reduction in child obesity prevalence may be reversed by a small increase in the risk of becoming overweight or obese in adulthood.

A cohort study of metformin exposure and survival in patients with stage I-III colorectal cancer

BACKGROUND

Preclinical evidence suggests a beneficial effect of metformin in colorectal cancer. This study aimed to investigate associations between metformin exposure and colorectal cancer-specific survival using population-level data.

METHODS

Adult patients with stage I-III colorectal cancer diagnosed from 2001 to 2006 were identified from the National Cancer Registry Ireland. Use of metformin and other antidiabetic medications was determined from a linked national prescription claims database. Multivariate Cox regression was used to estimate hazard ratios (HR) with 95% confidence intervals (CI) for associations between prediagnostic metformin exposure (versus nonmetformin antidiabetic drugs) and colorectal cancer-specific mortality. Models were stratified by antidiabetic drug coprescription and intensity of metformin exposure.

RESULTS

The cohort included 207 diabetics who received metformin, 108 diabetics not exposed to metformin, and 3,501 nondiabetic patients. In multivariate analyses, a nonsignificant reduction in colorectal cancer-specific mortality was observed for metformin-exposed patients relative to other treated diabetics (HR, 0.61; 95% CI, 0.37-1.01). In stratified analyses, no significant association was observed for patients receiving low-intensity metformin or metformin in combination with other antidiabetic drugs. High-intensity exclusive metformin use was associated with a significant reduction in colorectal cancer-specific mortality (HR, 0.44; 95% CI, 0.20-0.95).

CONCLUSIONS

Significant associations between metformin exposure and colorectal cancer-specific mortality were observed only for high-intensity exclusive metformin use in the diabetic cohort.

IMPACT

This study provides moderate evidence of an association between metformin exposure and improved colorectal cancer survival in a diabetic population. Additional studies in larger cohorts, with detailed information on diabetes severity, are required to confirm these results.

Feasibility and efficacy of a supervised exercise intervention in de-conditioned cancer survivors during the early survivorship phase: the PEACH trial

PURPOSE

This study aims to evaluate the feasibility and efficacy of an 8-week supervised exercise program in de-conditioned cancer survivors within 2-6 months of chemotherapy completion.

METHODS

Participants were randomly assigned to an 8-week, twice-weekly, supervised aerobic exercise training regime (n = 23) or a usual care group (n = 20). Feasibility was assessed by recruitment rate, program adherence and participant feedback. The primary outcome was aerobic fitness assessed by the Modified Bruce fitness test at baseline (0 weeks), post-intervention (8 weeks) and at 3-month follow-up. Secondary outcomes included physical activity, waist circumference, fatigue and quality of life.

RESULTS

The recruitment rate was 81 % and adherence to the supervised exercise was 78.3 %. Meaningful differences in aerobic fitness between the exercise and usual care groups at both the 8-week [mean 3.0 mL kg(-1) min(-1) (95 % CI -1.1-7.0)] and 3-month follow-up [2.1 mL kg(-1) min(-1) (-2.3-6.6)] were found, although these differences did not achieve statistical significance (p values >0.14). Self-reported physical activity increased in the exercise group (EG) compared to the usual care group at both 8-week (p = 0.01) and 3-month follow-up (p = 0.03) and significant differences in favour of the EG were found for physical well-being at both the 8-week (p = 0.03) and 3-month follow-up (p = 0.04). Improvements in fatigue (p = 0.01), total quality of life plus fatigue (p = 0.04), and a composite physical functioning score (p = 0.01) at the 3-month follow-up were also found.

CONCLUSION

The PEACH trial suggests that 8 weeks of supervised aerobic exercise training was feasible and may improve aerobic fitness, fatigue and quality of life in de-conditioned cancer survivors during the early survivorship phase.

IMPLICATIONS FOR CANCER SURVIVORS

Exercise interventions commenced in the early survivorship phase appear safe, feasible and may lead to improvements in QOL and fatigue.

Feasibility and efficacy of a supervised exercise intervention in de-conditioned cancer survivors during the early survivorship phase: the PEACH trial

PURPOSE

This study aims to evaluate the feasibility and efficacy of an 8-week supervised exercise program in de-conditioned cancer survivors within 2-6 months of chemotherapy completion.

METHODS

Participants were randomly assigned to an 8-week, twice-weekly, supervised aerobic exercise training regime (n = 23) or a usual care group (n = 20). Feasibility was assessed by recruitment rate, program adherence and participant feedback. The primary outcome was aerobic fitness assessed by the Modified Bruce fitness test at baseline (0 weeks), post-intervention (8 weeks) and at 3-month follow-up. Secondary outcomes included physical activity, waist circumference, fatigue and quality of life.

RESULTS

The recruitment rate was 81 % and adherence to the supervised exercise was 78.3 %. Meaningful differences in aerobic fitness between the exercise and usual care groups at both the 8-week [mean 3.0 mL kg(-1) min(-1) (95 % CI -1.1-7.0)] and 3-month follow-up [2.1 mL kg(-1) min(-1) (-2.3-6.6)] were found, although these differences did not achieve statistical significance (p values >0.14). Self-reported physical activity increased in the exercise group (EG) compared to the usual care group at both 8-week (p = 0.01) and 3-month follow-up (p = 0.03) and significant differences in favour of the EG were found for physical well-being at both the 8-week (p = 0.03) and 3-month follow-up (p = 0.04). Improvements in fatigue (p = 0.01), total quality of life plus fatigue (p = 0.04), and a composite physical functioning score (p = 0.01) at the 3-month follow-up were also found.

CONCLUSION

The PEACH trial suggests that 8 weeks of supervised aerobic exercise training was feasible and may improve aerobic fitness, fatigue and quality of life in de-conditioned cancer survivors during the early survivorship phase.

IMPLICATIONS FOR CANCER SURVIVORS

Exercise interventions commenced in the early survivorship phase appear safe, feasible and may lead to improvements in QOL and fatigue.

Aspirin use and mortality in men with localised prostate cancer: A cohort study

5084

Background: Cyclooxygenase-2 (COX-2) expression in prostate cancer has been associated with high grade tumours and poorer prognosis. Use of aspirin, a COX-2 inhibitor, has been associated with reduced prostate cancer mortality in some studies. These studies have not, however, provided information on the dose and timing of aspirin use. Methods: National Cancer Registry Ireland data was used to identify men with stage I-III prostate cancer (ICD10 C61) diagnosed 2001-2006. Aspirin use in the year preceding prostate cancer diagnosis was identified from linked prescription refill data (General Medical Services) and stratified by dose (low ≤75mg, high >75mg) and dosing intensity (proportion of days in that year with aspirin supply available). Cox proportional hazards models, adjusted for age, smoking status, year of incidence, comorbidity score, Gleason score, tumour size, pre-diagnostic statin use, and receipt of radiation (time varying) were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for associations between aspirin use and all-cause and prostate cancer-specific mortality. Interactions with tumour characteristics were examined. Results: 2,936 men with stage I-III prostate cancer were identified (aspirin users, N=1,131; 38.5%). Median patient follow-up was 5.5 years. In multivariate analyses, aspirin use was not associated with a significant reduction in prostate cancer-specific (HR 0.90, 95% CI 0.68-1.20) or all-cause mortality (HR 0.98, 95% CI 0.84-1.15). In dose response analyses aspirin use was associated with a significantly lower risk of prostate cancer-specific mortality in men receiving >75mg of aspirin (HR 0.59, 95% CI 0.35-1.00, p=0.048) but not ≤75mg aspirin (HR 1.01, 95% CI 0.75-1.37, p=0.938). Stronger associations were also observed in men with higher aspirin dosing intensity or a Gleason score >7. Conclusions: Pre-diagnostic aspirin use, measured using objective prescription refill data, was associated with a significant reduction in prostate cancer-specific mortality in men with stage I-III prostate cancer receiving >75mg of aspirin. These results confirm previous findings, and provide important new information regarding the dose of aspirin associated with survival benefit.

Repeatability of the measurement of aortic pulse wave velocity (aPWV) in the clinical assessment of arterial stiffness in community-dwelling older patients using the Vicorder(®) device

BACKGROUND

Pulse wave velocity measured using the Vicorder(®) apparatus is a non-invasive indicator of arterial stiffness. The objective of this study was to assess its repeatability in older patients when used by medical professionals with limited experience of the technique.

METHODS

Aortic pulse wave velocity (aPWV) was measured using the Vicorder(®) system four times using the conventional pathway and twice by adapted pathway in 25 consecutive ambulant patients (15 male) after they rested supine for 15 min. A nurse and a doctor independently and alternately measured PWV using the same equipment and were blinded to their colleague's PWV readings. 'Within' and 'between' observer differences were assessed using intra-class correlation coefficients (rI) and 95% limits of agreement (95% LoA) derived from Bland-Altman plots.

RESULTS

Mean age was 79.8 (mean blood pressure [BP] = 133/69, Mean heart rate [HR]: 70.9). Mean PWV was 11.73 (Standard Deviation [SD] 2.6-3.6). 'Between' and 'within' observer repeatability was high, with rIs ranging from 0.8-0.93. The repeatability index for 'between' nurse and doctor measures was slightly lower (rI = 0.88) when an adapted cuff measure was used in assessing PWV compared to conventional cuff measures (rI = 0.93). Mean PWV readings 'between' observers differed by only 0.094 (95% CI -0.24 to 1.59).

CONCLUSION

When undertaken by operators with limited previous technical experience, both 'within' and 'between' observer repeatability of PWV measurement was high. This method has the potential to be included in the clinical assessment of arterial stiffness in older ambulant patients.

Modelling Coronary Heart Disease Mortality declines in the Republic of Ireland, 1985-2006

BACKGROUND

Consistent declines in coronary heart disease (CHD) death rates have been previously observed in Ireland since 1985.

AIMS & METHODS

To use the previously validated Irish IMPACT CHD mortality model to further examine the subsequent CHD mortality falls from 1985 through to 2006, and to determine the contribution of risk factor changes and "evidence based" treatments to this decline by age and gender.

RESULTS

CHD mortality rates fell by 68% in men (63% in 65-84 years) and by 69% in women (66% in 65-84 years). This resulted in approximately 6450 fewer CHD deaths than if mortality rates had not changed. Overall, approximately 40% (38% in men; 45% in women) of the CHD mortality decline could be attributed to improvements in treatment uptake, particularly secondary prevention (12%), angina (9%), and heart failure therapies (8%). Approximately 48% of the CHD mortality decline was attributable to risk factor improvements (54% in men; 37% in women); the biggest contributions came from falls in population systolic pressure (28%), cholesterol (24%), and physical inactivity levels (10%). Negative trends in diabetes and obesity levels generated an estimated 17% additional CHD deaths. The largest benefits from improvements in risk factors were seen in men aged 25-64 years, while the greatest treatment benefits occurred in women aged 65-84 years. The model explained approximately 88% of the observed mortality declines.

CONCLUSION

Falls in CHD mortality have continued in both sexes in Ireland, but with notable gender and age differences. The continued increase in diabetes and obesity levels is particularly worrying.

A prospective investigation of predictive and modifiable risk factors for breast cancer in unaffected BRCA1 and BRCA2 gene carriers

Background

Breast cancer is the most common female cancer worldwide. The lifetime risk of a woman being diagnosed with breast cancer is approximately 12.5%. For women who carry the deleterious mutation in either of the BRCA genes, BRCA1 or BRCA2, the risk of developing breast or ovarian cancer is significantly increased. In recent years there has been increased penetrance of BRCA1 and BRCA2 associated breast cancer, prompting investigation into the role of modifiable risk factors in this group. Previous investigations into this topic have relied on participants recalling lifetime weight changes and subjective methods of recording physical activity. The influence of obesity-related biomarkers, which may explain the link between obesity, physical activity and breast cancer risk, has not been investigated prospectively in this group. This paper describes the design of a prospective cohort study investigating the role of predictive and modifiable risk factors for breast cancer in unaffected BRCA1 and BRCA2 gene mutation carriers.

Methods/design

Participants will be recruited from breast cancer family risk clinics and genetics clinics. Lifestyle risk factors that will be investigated will include body composition, metabolic syndrome and its components, physical activity and dietary intake. PBMC telomere length will be measured as a potential predictor of breast cancer occurrence. Measurements will be completed on entry to the study and repeated at two years and five years. Participants will also be followed annually by questionnaire to track changes in risk factor status and to record cancer occurrence. Data will be analysed using multiple regression models. The study has an accrual target of 352 participants.

Discussion

The results from this study will provide valuable information regarding the role of modifiable lifestyle risk factors for breast cancer in women with a deleterious mutation in the BRCA gene. Additionally, the study will attempt to identify potential blood biomarkers which may be predictive of breast cancer occurrence.