Genetic susceptibility, dietary antioxidants, and long-term incidence of age-related macular degeneration in two populations.

OBJECTIVE: To examine effect modification between genetic susceptibility to age-related macular degeneration (AMD) and dietary antioxidant or fish consumption on AMD risk. DESIGN: Pooled data analysis of population-based cohorts. PARTICIPANTS: Participants from the Blue Mountains Eye Study (BMES) and Rotterdam Study (RS). METHODS: Dietary intakes of antioxidants (lutein/zeaxanthin [LZ], ß-carotene, and vitamin C), long-chain omega-3 polyunsaturated fatty acids, and zinc were estimated from food frequency questionnaires. The AMD genetic risk was classified according to the number of risk alleles of CFH (rs1061170) or ARMS2 (rs10490924) as low (no or 1 risk allele) or high (≥ 2 risk alleles). Interactions between dietary intake and genetic risk levels were assessed. Associations between dietary intake and AMD risk were assessed comparing the highest with the 2 lower intake tertiles by genetic risk subgroups using discrete logistic regression, conducted in each study separately and then using pooled data. Participants without AMD lesions at any visit were controls. We adjusted for age and sex in analyses of each cohort sample and for smoking status and study site in pooled-data analyses. MAIN OUTCOME MEASURES: All 15-year incident late AMD cases were confirmed by chief investigators of the Beaver Dam Eye Study, BMES, and RS. Intergrader reproducibility was assessed in an early AMD subsample, with 86.4% agreement between BMES and RS graders, allowing for a 1-step difference on a 5-step AMD severity scale. RESULTS: In pooled data analyses, we found significant interaction between AMD genetic risk status and LZ intake (P=0.0009) but nonsignificant interactions between genetic risk status and weekly fish consumption (P=0.05) for risk of any AMD. Among participants with high genetic risk, the highest intake tertile of LZ was associated with a >20% reduced risk of early AMD, and weekly consumption of fish was associated with a 40% reduced risk of late AMD. No similar association was evident among participants with low genetic risk. No interaction was detected between ß-carotene or vitamin C and genetic risk status. CONCLUSIONS: Protection against AMD from greater LZ and fish consumption in persons with high genetic risk based on 2 major AMD genes raises the possibility of personalized preventive interventions.

Serum L-arginine and endogenous methylarginine concentrations predict irritable bowel syndrome in adults: A nested case-control study.

BACKGROUND & AIMS: Nitric oxide, a major inhibitory nonadrenergic, noncholinergic neurotransmitter that relaxes smooth muscle, may be implicated in the pathophysiology of visceral hypersensitivity in irritable bowel syndrome (IBS). Impaired bioavailability of the nitric oxide precursor molecule L-arginine and higher concentrations of methylarginines (endogenous inhibitors of nitric oxide synthesis) are known to impair nitric oxide synthesis in numerous gastrointestinal cell types. We therefore examined serum concentrations of L-arginine and the methylarginines in a nested case-control study, to assess whether these factors are associated with adult IBS. METHODS: Data on clinical characteristics, methylarginines, and L-arginine (measured using LC-MS/MS) were collected from a random population-based cohort of Australian adults (median age = 64 years; IQR = 60-70). Cases of IBS, defined according to Rome III criteria (N = 156), and controls (N = 332) were identified from within the cohort at the 5-year follow-up. RESULTS: In adjusted logistic regression analyses, L-arginine, asymmetric dimethylarginine, symmetric dimethylarginine, L-arginine/asymmetric dimethylarginine ratio, and Kessler-10 psychological distress scores were significantly associated with IBS (p < 0.05). [Correction added on 18 September 2021, after first online publication: In the preceding sentence, the value (p > 0.05) has been changed to (p < 0.05)]. Similar results were found for IBS subtypes. Higher serum L-arginine concentration had the strongest association with IBS diagnosis, with an odds ratio of 9.03 for those with serum L-arginine at the 75th (84 µmol/L) versus 25th (46 µmol/L) percentile (95% CI: 5.99-13.62). L-arginine had the best discriminative ability with a bias-adjusted area under the receiver operator characteristic curve of 0.859. CONCLUSIONS: Higher serum concentrations of L-arginine and endogenous methylarginines are strongly associated with IBS in adults.

Population-based detection of systolic and diastolic dysfunction with amino-terminal pro-B-type natriuretic peptide.

BACKGROUND: There is limited information regarding the clinical utility of amino-terminal pro-B-type natriuretic peptide (NT-proBNP) for the detection of left ventricular (LV) dysfunction in the community. We evaluated predictors of circulating NT-proBNP levels and determined the utility of NT-proBNP to detect systolic and diastolic LV dysfunction in older adults. METHODS: A population-based sample of 1229 older adults (mean age 69.4 years, 50.1% women) underwent echocardiographic assessment of cardiac structure and function and measurement of circulating NT-proBNP levels. RESULTS: Predictors of NT-proBNP included age, female sex, body mass index, and cardiorenal parameters (diastolic dysfunction [DD] severity; LV mass and left atrial volume; right ventricular overload; decreasing ejection fraction [EF] and creatinine clearance). The performance of NT-proBNP to detect any degree of LV dysfunction, including mild DD, was poor (area under the curve 0.56-0.66). In contrast, the performance of NT-proBNP for the detection of EF < or = 40% and moderate-severe DD was strong with area under the curve of > 0.90 regardless of age and sex; history of hypertension, diabetes, coronary artery disease; or body mass category. The ability of NT-proBNP to detect EF < or = 40% and/or moderate-severe DD was optimized by using age/sex-specific limits. Of "false-positive" tests, 88% (124/141) were explained after considering cardiorenal determinants of NT-proBNP levels. CONCLUSIONS: Amino-terminal pro-B-type natriuretic peptide is a suboptimal marker of mild LV dysfunction, but performs strongly as a marker of EF < or = 40% and/or moderate-severe DD in the community. Most subjects with a positive NT-proBNP test, using age/sex-specific cutoffs, had prognostically significant abnormalities of cardiac structure or function.

Prevalence of low serum folate and vitamin B12 in an older Australian population.

OBJECTIVE: To examine the prevalence of low serum folate and vitamin B12, in association with elevated serum homocysteine, in a representative sample of older Australians. METHODS: During 1997-2000, 3,508 persons aged 50+ years were examined in a population-based cohort study conducted in two postcodes, west of Sydney, Australia. Of these, 2,901 participants (82.7%) provided fasting blood for estimates of serum folate, vitamin B12 and total homocysteine. RESULTS: Low serum B12 (< 185 pmol/L) was found in 22.9% of participants and low serum folate (< 6.8 nmol/L) in 2.3% of participants. Among those people with very low serum vitamin B12 (< 125 pmol/L) and low serum folate, 51% had elevated homocysteine. CONCLUSIONS: Low serum levels of vitamin B12 and elevated serum homocysteine are relatively frequent in older Australians. IMPLICATIONS: Appropriate public health action should be considered to reduce the prevalence of low serum vitamin B12 and elevated homocysteine in older Australians.

Access to drinking-water and arsenicosis in Bangladesh.

The discovery of arsenic contamination in groundwater has challenged efforts to provide safe drinking-water to households in rural Bangladesh. Two nationally-representative surveys in 2000 and 2002 investigated water-usage patterns, water-testing, knowledge of arsenic poisoning, and behavioural responses to arsenic contamination. Knowledge of arsenicosis rose between the two surveys among women from 42% to 64% but awareness of consequences of arsenic remained limited; only 13% knew that it could lead to death. Behavioural responses to arsenic have been limited, probably in part because of the lack of concern but also because households are uncertain of how best to respond and have a strong preference for tubewell water even when wells are known to be contaminated. Further work conducted by the survey team highlighted the difficulties in providing alternative sources of water, with many households switching back to their original sources of water.

The effect of timing when seeking permission to access personal health services utilization records.

PURPOSE: To determine if the timing for requesting signed permission to access personal health services utilization records affects authorization or survey response rates. METHODS: A screening question about in-principle willingness to permit access to personal health services utilization records was included in a mail-based survey of two Australian female samples (n = 292). Half of the surveys for each sample also included a separate form to be signed to approve access. For the other half the form was not included, but an authorization form was sent subsequently. RESULTS: Around 30% of participants signed the authorization form and there was no significant difference between the randomized groups [ relative risk (RR) = 0.95, 95% confidence interval (CI) = 0.72-1.25). However, the response rate to the postal survey was significantly higher for the group who received the form after returning the questionnaire (60% compared to 46%; RR = 1.31, 95% CI = 1.06-1.62). CONCLUSIONS: A two-staged approach, with a time lag between seeking in principle permission to access personal health services utilization records and requesting signed authorization, does not affect authorization rates. In addition, it results in a significantly higher survey response rate than if an authorization form is included with the survey.

Patients with advanced cancer and family caregivers' knowledge of health and community services: a longitudinal study.

The present study examines the knowledge of health and community services reported by patients with advanced cancer and their family caregivers, and compares patient-stated use with their knowledge of availability. A longitudinal study of the quality of life of patients with advanced cancer was conducted out of the cancer services of The Canberra Hospital, a teaching service, in Canberra, Australian Capital Territory, Australia. Some 317 subjects were recruited sequentially, comprising patients (n = 181) and their nominated family caregivers (n = 136). Patients were more aware of the available health and community support services compared with their caregivers, and differences were significant for most allied professional services, as well as some key supportive care institutions and community programmes. Knowledge of community support services was variable and low for those specifically associated with terminal care. While congruence of knowledge for dyads was quite low in some areas, overall household knowledge was high. The identified sources were mainly non-medical. Nurses, social workers and alternative practitioners, as well as family, friends and commercial sources were the main categories which were identified. No statistically significant changes in knowledge or sources of information occurred over time. Further longitudinal research would assist healthcare teams to understand the role of health and community services in the advanced cancer setting. The identification of systemic and regional weaknesses in communication may assist in improving family knowledge and improve timely access to important supports in the advanced cancer setting.

Intervention trial to assess arsenic exposure from food crops in Bangladesh.

The authors assessed the contribution of food irrigated with arsenic-contaminated water to human exposure to arsenic in Bangladesh. An intervention trial was conducted in a village in the Jessore District of Bangladesh, where irrigation water had been field-tested in March 2000 and was found to contain arsenic with concentrations ranging from 100 to 500 microg/l. In May 2000, a random sample of 63 households was selected from the village, and 1 eligible person from each household was recruited to the study and randomized to an intervention or control group. The intervention group received food purchased from a village where irrigation water was found to contain < 10 microg/l arsenic. The control group received food purchased from markets in the study village, where irrigation water was found to contain > 100 microg/l arsenic. Pre- and postintervention urine samples were collected for urinary arsenic speciation assays. Preintervention, the mean urinary total arsenic concentrations were 139.25 microg/l and 129.15 microg/l for the intervention and control groups, respectively. These concentrations did not change significantly following intervention. Arsenic concentrations in samples of selected raw and cooked foods from the low-contamination area did not contain less arsenic than samples from the high-contamination area. Further studies to investigate the arsenic content of food grown in areas with high and low arsenic contamination of irrigation water are recommended.

Serum methylarginines and spirometry-measured lung function in older adults.

RATIONALE: Methylarginines are endogenous nitric oxide synthase inhibitors that have been implicated in animal models of lung disease but have not previously been examined for their association with spirometric measures of lung function in humans. OBJECTIVES: This study measured serum concentrations of asymmetric and symmetric dimethylarginine in a representative sample of older community-dwelling adults and determined their association with spirometric lung function measures. METHODS: Data on clinical, lifestyle, and demographic characteristics, methylated arginines, and L-arginine (measured using LC-MS/MS) were collected from a population-based sample of older Australian adults from the Hunter Community Study. The five key lung function measures included as outcomes were Forced Expiratory Volume in 1 second, Forced Vital Capacity, Forced Expiratory Volume in 1 second to Forced Vital Capacity ratio, Percent Predicted Forced Expiratory Volume in 1 second, and Percent Predicted Forced Vital Capacity. MEASUREMENTS AND MAIN RESULTS: In adjusted analyses there were statistically significant independent associations between a) higher asymmetric dimethylarginine, lower Forced Expiratory Volume in 1 second and lower Forced Vital Capacity; and b) lower L-arginine/asymmetric dimethylarginine ratio, lower Forced Expiratory Volume in 1 second, lower Percent Predicted Forced Expiratory Volume in 1 second and lower Percent Predicted Forced Vital Capacity. By contrast, no significant associations were observed between symmetric dimethylarginine and lung function. CONCLUSIONS: After adjusting for clinical, demographic, biochemical, and pharmacological confounders, higher serum asymmetric dimethylarginine was independently associated with a reduction in key measures of lung function. Further research is needed to determine if methylarginines predict the decline in lung function.

Correlation and agreement of self-assessed and objective skin disease severity in a cross-sectional study of patients with acne, psoriasis, and atopic eczema.

BACKGROUND: Previous studies have shown variable correlation of patients' self-assessed skin severity measures and clinician-assessed objective measures of severity. But, generally, correlation has not been as good as might be expected for conditions in which the objective physical extent of skin disease is apparent to the sufferer to an extent that is not applicable in many other diseases. METHODS: This paper reports agreement and correlation of self-assessed and objective severity measures in a study of 108 subjects with acne, psoriasis, or atopic eczema. The study was a cross-sectional study examining psychological associations of these skin diseases. Objective severity was assessed with the Leeds technique (acne), the Psoriasis Area and Severity Index, and Six Area Six Sign Atopic Dermatitis instruments. Agreement is a more appropriate measure than correlation in this situation and was measured with weighted kappa, while correlation was measured with Spearman's rank correlation. RESULTS: There was a modest correlation of ρ = 0.46 and similarly very modest agreement of 0.35 (weighted kappa) of self-assessed and clinician-assessed disease severity. Furthermore, self-assessed (but not clinician-assessed) severity was statistically associated with psychological morbidity in this study; i.e. - depression, anxiety, and overall psychological morbidity. CONCLUSIONS: Clinicians should consider psychological sequelae of skin disease, not only in those with objectively more severe disease but in patients across the severity spectrum. Both observational and interventional studies of skin disease should include both clinician-assessed and self-assessed measures of severity among assessed variables.

Respiratory health effects of exposure to low-NOx unflued gas heaters in the classroom: a double-blind, cluster-randomized, crossover study.

BACKGROUND: There are long-standing concerns about adverse effects of gas appliances on respiratory health. However, the potential adverse effect of low-NOx (nitrogen oxide) unflued gas heaters on children's health has not been assessed. OBJECTIVES: Our goal was to compare the respiratory health effects and air quality consequences of exposure to low-NOx unflued gas heaters with exposure to non-indoor-air-emitting flued gas heaters in school classrooms. METHODS: We conducted a double-blind, cluster-randomized, crossover study in 400 primary school students attending 22 schools in New South Wales, Australia. Children measured their lung function and recorded symptoms and medication use twice daily. Nitrogen dioxide (NO2) and formaldehyde concentrations were measured in classrooms using passive diffusion badges. RESULTS: NO2 concentrations were, on average, 1.8 times higher [95% confidence interval (CI), 1.6-2.1] and formaldehyde concentrations were, on average, 9.4 ppb higher (95% CI, 5.7-13.1) during exposure to unflued gas versus flued gas heaters. Exposure to the unflued gas heaters was associated with increased cough reported in the evening [odds ratio (OR) = 1.16; 95% CI, 1.01-1.34] and wheeze reported in the morning (OR = 1.38; 95% CI, 1.04-1.83). The association with wheeze was greater in atopic subjects. There was no evidence of an adverse effect on lung function. CONCLUSIONS: We conclude that classroom exposure to low-NOx unflued gas heaters causes increased respiratory symptoms, particularly in atopic children, but is not associated with significant decrements in lung function. It is important to seek alternative sources of heating that do not have adverse effects on health.

The validation of a self-report measure and physical activity of Australian Aboriginal and Torres Strait Islander and non-Indigenous rural children.

PURPOSE: To validate a self-report measure of physical activity for both Australian Aboriginal and Torres Strait Islander and non-Indigenous rural children, and to describe their physical activity participation. METHODS: In this cross-sectional study, 84 Aboriginal and Torres Strait Islander and 146 non-Indigenous children aged 10-12 years old completed the Many Rivers Physical Activity Recall Questionnaire (MRPARQ), a modified version of the Adolescent Physical Activity Recall Questionnaire (APARQ). A sub-group (n=86) wore an accelerometer for seven consecutive days in order to validate the instrument. RESULTS: Pearson and Intra Class Correlation coefficients between the survey and acceleromtery for weekdays only are 0.31 and 0.16, respectively, for Aboriginal and Torres Strait Islander children, and 0.38 and 0.31, respectively, for non-Indigenous children, and demonstrate a modest (p<0.05) correlation. Self-reported MVPA for Aboriginal and Torres Strait Islander children is between 162 and 172 minutes/day, and is 125 minutes by accelerometer; for non-Indigenous children MVPA is between 123 and 149 minutes (survey) and 107 minutes (accelerometer). CONCLUSION: Australian Aboriginal and Torres Strait Islander children's self-report of physical activity is at least as valid as non-Indigenous children, given culturally appropriate support; they tend to be more active than non-Indigenous children. IMPLICATIONS: The MRPARQ can be administered with Aboriginal and Torres Strait Islander and non-Indigenous children.

Estimating the global disease burden due to ultraviolet radiation exposure.

BACKGROUND: WHO's global burden of disease studies, undertaken since 1996, apportion the total global disease burden, measured in disability-adjusted life years (DALYs), to specific diseases and injuries. Recent assessments of the relative burden due to specific environmental risk factors, plus an understanding of the nature of the risk factor, may guide resource allocation in risk factor management. We report here the global disease burden due to ultraviolet radiation (UVR) exposure. METHODS: A systematic literature review identified nine diseases with sufficient evidence of a causal relationship with UVR exposure and for which the population attributable fraction (PAF) for UVR could be estimated. For cutaneous malignant melanoma and cataract, the PAF was directly applied to disease burdens already calculated by WHO. For seven other diseases, we developed population-level exposure-disease relationships and used these to calculate disease incidence and mortality, and thence disease burden. We also estimated the disease burden from rickets, osteomalacia and osteoporosis that might result if global UVR exposure was reduced to very low levels. RESULTS: UVR exposure is a minor contributor to the world's disease burden, causing an estimated annual loss of 1.6 million DALYs; i.e. 0.1% of the total global disease burden. A markedly larger annual disease burden, 3.3 billion DALYs, might result from reduction in global UVR exposure to very low levels. CONCLUSIONS: Sun protection messages are important to prevent diseases of UVR exposure. However, without high dietary (or supplemental) intake of vitamin D, some sun exposure is essential to avoid diseases of vitamin D insufficiency.

Fluctuating awareness of treatment goals among patients and their caregivers: a longitudinal study of a dynamic process.

BACKGROUND: Because increasing numbers of people now survive for months or years with advanced cancer, communication between patients, service providers, and family caregivers often continues over long periods. Hence, understanding of the goals of medical treatment may develop and change as time elapses and disease progresses. This understanding is closely related to the "awareness of dying," which has been studied in both qualitative and quantitative research. However, when both a patient and family caregiver are involved, the question of "awareness" becomes more complex. A recent longitudinal study reported on patient and caregiver knowledge of treatment goals, but no comparison of such knowledge using matched interview schedules and paired data analysis has been provided. This report examines patterns of awareness and factors associated with these patterns. MATERIALS AND METHODS: One hundred sixty-three patients with incurable cancer and their nominated principal family caregivers (136) were recruited from The Canberra Hospital Oncology Services. Participants' understanding of the treatment goals were measured by interview questions at weeks 1 and 12. RESULTS: One-third of both patients and caregivers understood that the treatment goal was not curative; however, not all patient and caregiver pairs had the same understanding. In 15% of pairs, both patient and caregiver believed that the goal of treatment was curative, while another 13% said that they did not know the aim of the treatment. Thirty-nine percent of pairs registered incongruent responses in which only one member of the pair understood that the treatment was not intended to cure the disease. Over time, a few respondents changed their perception of the treatment goals toward accurate clarification. Bivariate analysis using an awareness variable, constructed for the purpose, showed that in 6 months before death, at least one person in 89% of pairs understood that the treatment was noncurative. Time-to-death, gender, and place of residence were also important predictors of knowledge. CONCLUSIONS: Discrepancies between patients and their caregivers may complicate the delivery of effective care when patients are seriously ill. Misunderstanding or uncertainty about treatment goals will obstruct proper informed consent. Health professionals providing care for families dealing with advanced cancer must recognize that the discussion of treatment goals is a dynamic process, which may require them to extend their communication skills.

Prevalence of heart failure and systolic ventricular dysfunction in older Australians: the Canberra Heart Study.

OBJECTIVE: To estimate the prevalence of heart failure (HF) and left ventricular (LV) systolic dysfunction in a population-based sample of older Australians. DESIGN, SETTING AND PARTICIPANTS: A cross-sectional survey of 2000 randomly selected residents of Canberra, aged 60-86 years, conducted between February 2002 and June 2003. Participants were assessed by history, physical examination by a cardiologist, and echocardiography. MAIN OUTCOME MEASURES: Age- and sex-specific prevalence rates of clinical HF and LV systolic dysfunction (defined as LV ejection fraction < or = 50%). RESULTS: Of 1846 people eligible for our study, 1388 (75%) agreed to participate and 1275 completed all investigations (mean age, 69.4 years; 50% men). In the study sample, 72 subjects (5.6%; 95% CI, 4.4%-7.1%) had clinical HF that had been previously diagnosed and was confirmed by our assessment. A further 0.6% (95% CI, 0.3%-1.2%) had undiagnosed clinical HF (ie, evidence of structural heart disease and symptoms/signs of cardiac insufficiency without a previous diagnosis of clinical HF). Thus, the overall prevalence of clinical HF in the sample was 6.3% (95% CI, 5.0%-7.7%). Clinical HF increased in prevalence with advancing age (a 4.4-fold increase from the 60-64-years age group to the 80-86-years age group; P < 0.0001). Of the 75 subjects (5.9%; 95% CI, 4.7%-7.3%) with LV systolic dysfunction, 44 (59%) were in the preclinical stage of disease. CONCLUSION: Diagnosed HF cases represent the "tip of the iceberg" for the national burden of HF and LV systolic dysfunction. Clinically identifiable HF cases can remain undiagnosed, and the majority of people with LV systolic dysfunction are in a preclinical stage of the disease.

Issues in assessing the validity of nutrient data obtained from a food-frequency questionnaire: folate and vitamin B12 examples.

OBJECTIVE: To compare methods used to assess the validity of nutrient intake data obtained from a food-frequency questionnaire (FFQ), using folate and vitamin B12 as nutrient examples. DESIGN: Cross-sectional sample from a population cohort. SETTING: Two postcode areas west of Sydney, Australia. SUBJECTS: In total, 2895 people aged 49 years and older provided dietary data using a semi-quantitative FFQ (79% of 3654 subjects examined). The validity of the FFQ was assessed against three 4-day weighed food records (WFRs) completed by 78 people (mean age 70 years). RESULTS: Folate and vitamin B12 validity data were assessed using different methods. The Spearman ranked correlations (energy-adjusted) were 0.66 for folate and 0.38 for vitamin B12. Using the Bland-Altman method, following loge transformation, no linear trend existed between the differences and means for folate and vitamin B12. Large differences existed between the FFQ and WFR in individual cases, particularly for vitamin B12. Finally, data were divided into quintile categories for the test and reference method: 79% classified folate within one quintile, 65% classified vitamin B12 within one quintile; there was no gross misclassification for folate and only 3% misclassification for vitamin B12. CONCLUSIONS: Different methods of analysis provided different information about the validity of the FFQ. Correlation coefficients should not be used alone to assess the validity of nutrient data, but should be used in conjunction with Bland-Altman analyses. Depending on the use of the data, additional assessment of classification categories is recommended. This worked example demonstrates that absolute intakes of folate and vitamin B12 should be used with caution.

Family caregiver knowledge of treatment intent in a longitudinal study of patients with advanced cancer.

GOALS OF WORK: Caregivers have become part of a triad of care and frequently attend patient consultations in the ambulatory cancer setting. Effective caregiving and decision making require that they understand the course of the disease and the changing treatment goals. This study sought to evaluate caregiver perception of treatment intent. PATIENTS AND METHODS: A cohort of 317 subjects (181 patients and 136 caregivers) from The Canberra Hospital's Cancer Services were followed for 6 months. Caregiver understanding of patient treatment intent was measured over time together with sources of information. MAIN RESULTS: Most caregivers understood that the illness was life-threatening (92% at week 12) and that treatment goals were to control illness and improve quality of life. Only half understood that treatment was noncurative (48% at week 12); 27% were unsure and 25% believed that treatment would cure. A high proportion of caregivers identified the specialist as the source of information (77%) and almost half also included the general practitioner (47%). These figures remained fairly constant over time. There were significant gender and age differences in understanding. At baseline, more women than men had an accurate perception of treatment intent and these numbers increased over time. Men's perception did not change. CONCLUSIONS: Caregivers' ability to fully engage in the task of caring for those with a terminal illness may be hampered by their lack of understanding of the treatment patients receive.