Muscle Mass Index and Animal Source of Dietary Protein Are Positively Associated with Insulin Resistance in Participants of the NuAge Study.

OBJECTIVES: Contribute evidence towards the complex interrelationships of body composition, insulin sensitivity and protein intake independently from adiposity in an older population. DESIGN: This is a cross-sectional analysis of an existing dataset in which a literature-supported model linking together the variables of interest is tested using path analysis. SETTING: The loss of muscle mass has been implicated in the development of insulin resistance. We propose to test associations of muscle mass with insulin sensitivity and their respective associations with animal and vegetable sources of protein intake, independently from adiposity. PARTICIPANTS: Non-diabetic participants aged 68-82 years from the NuAge study with all available measures (n=441) were included. MEASUREMENTS: A model considering age, sex, chronic diseases, physical activity; smoking and sources of protein intake influencing body composition components and insulin sensitivity was created and tested with Path Analysis for their independent associations. Muscle mass index (MMI; kg/height in m2) and % body fat were derived from DXA and BIA. Insulin resistance was estimated by the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) score and physical activity by the Physical Activity Scale for the Elderly (PASE) questionnaire. Protein intakes were obtained from three non-consecutive 24h-diet recalls. RESULTS: In the final model, direct positive associations were observed between HOMA-IR score and MMI (ß=0.42; 95%CI: 0.24; 0.6) and % body fat (ß=0.094; 95%CI: 0.07; 0.11). There were no direct associations between animal protein intake and MMI or with HOMA-IR. There was a significant direct negative association between plant protein intake and MMI (ß= -0.068; 95%CI: -0.13; -0.003) and significant indirect associations mediated through MMI and % body fat between HOMA-IR and animal protein intake (ß=0.0321; 95%CI: 0.01; 0.05), as well as plant protein intake (ß= -0.07; 95%CI: -0.1; 0.0). CONCLUSIONS: Our final model indicated that MMI and HOMA score were significantly positively associated. Protein intake sources were related to HOMA-IR score differently through MMI and % body fat, respectively.

Longitudinal circulating concentrations of long-chain polyunsaturated fatty acids in the third trimester of pregnancy in gestational diabetes.

AIM: Gestational diabetes mellitus is a common complication of pregnancy. Long-chain polyunsaturated fatty acids (LCPUFA) are essential for fetal neurodevelopment. Docosahexaenoic acid (DHA) is the predominant n-3 LCPUFA in the brain and retina. Circulating absolute concentrations of total n-3 and n-6 LCPUFAs rise during normal pregnancy. It remains unclear whether gestational diabetes may affect the normal rise in circulating concentrations of LCPUFAs in the third trimester of pregnancy - a period of rapid fetal neurodevelopment. This study aimed to address this question. METHODS: In a prospective singleton pregnancy cohort, fatty acids in fasting plasma total lipids were measured at 24-28 and 32-35 weeks of gestation in women with (n = 24) and without gestational diabetes mellitus (n = 116). Fatty acid desaturase activity indices were estimated by relevant product-to-precursor fatty acid ratios. Dietary nutrient intakes were estimated by a food frequency questionnaire. RESULTS: Plasma absolute concentrations of total n-6 LCPUFAs rose significantly between 24-28 and 32-35 weeks of gestation in women with or without gestational diabetes, whereas total n-3 LCPUFAs and DHA concentrations rose significantly only in women without gestational diabetes (all P < 0.01). Delta-5 desaturase indices (20:4n-6/20:3n-6) were similar, but delta-6 desaturase indices (18:3n-6/18:2n-6) were significantly lower in women with gestational diabetes at 32-35 weeks of gestation. Dietary intakes of all fatty acids were comparable. CONCLUSION: The normal rise in circulating absolute concentrations of DHA and total n-3 LCPUFAs in the third trimester of pregnancy may be compromised in gestational diabetes, probably due to impaired synthesis or mobilization rather than dietary intake difference.

Intakes of folate, vitamin B6 and B12 and risk of depression in community-dwelling older adults: the Quebec Longitudinal Study on Nutrition and Aging.

BACKGROUND/OBJECTIVES: Depression can decrease quality of life and affect health outcomes in older population. We investigated whether different intake levels of folate, vitamin B6 and B12 were associated with a 3-year depression incidence among generally healthy, community-dwelling older men and women. SUBJECTS/METHODS: Participants in the Québec Longitudinal Study on Nutrition and Aging (NuAge), free of depression (that is, 30-item Geriatric Depression Scale (GDS) <11) at baseline (N=1368; 74 ± 4 years old; 50.5% women), were screened annually for incident depression (GDS ⩾ 11) or antidepressant medication. Tertiles of intakes (food only and food+supplements) were obtained from the mean of three non-consecutive 24-h recalls at baseline. Sex-stratified multiple logistic regression models were adjusted for age, physical activity, physical functioning, stressful life events and total energy intake. RESULTS: Over 3 years, 170 participants were identified as depressed. Women in the highest tertile of B6 intake from food were 43% less likely to become depressed when adjusting for demographic and health factors (multivariate odds ratio (OR) 0.57, 95% confidence interval (CI) 0.39-0.96), but adjustment for energy intake attenuated the effect. Men in the highest tertile of dietary B12 intake had decreased risk of depression (energy-adjusted multivariate OR 0.42, 95% CI 0.20-0.90). No other association was observed. CONCLUSIONS: This study provides some evidence of decreased depression risk among women with higher intakes of vitamin B6 from food, which was dependent on total energy intake, and among men with higher intakes of B12 from food, independently of energy intake.

Dietary patterns and incidence of depression in a cohort of community-dwelling older Canadians.

OBJECTIVES: To investigate the association of dietary patterns with a 3-year incidence of depression among healthy older adults. DESIGN: Multiple logistic regression models adjusted for age, sex, marital status, smoking, education, total energy intake, physical activity, body mass index, hypertension, functional autonomy, cognitive functioning, social activities, and stressful life events. Energy and macronutrient intakes were also analyzed as potential predictors of depression. SETTING: Cities of Montréal, Laval, and Sherbrooke in Quebec, CA. PARTICIPANTS: Community-dwelling older adults, free of depression at baseline (N=1,358, 67-84 y), followed for 3y in the Québec Longitudinal Study on Nutrition and Aging (NuAge). MEASUREMENTS: Dietary patterns derived from principal components analysis of three 24 h-recalls at baseline, and depression incidence as measured by the 30-item Geriatric Depression Scale (≥11) and/or use of antidepressants at follow-up years. RESULTS: 170 people (63% women) became depressed over the 3 years. People in the highest tertile of adherence to the "varied diet" had lower risk of depression before adjustment (OR 0.58, 98% C.I. 0.38-0.86) but not significant once age and sex were controlled. No other dietary pattern was associated with the incidence of depression. The highest tertile of energy intake was associated with lower depression incidence after controlling for all confounders (OR 0.55, 95%CI 0.34-0.87). CONCLUSION: Among healthy older adults, dietary patterns do not appear to be related to depression. Those who eat less, however, possibly reflecting declining health, are at higher risk of becoming depressed.

Baseline determinants of global diet quality in older men and women from the NuAge cohort.

UNLABELLED: Judicious food choices are of prime importance during aging. OBJECTIVES: This study was conducted to identify individual and collective attributes determining global diet quality (DQ). METHODOLOGY: Participants were 1,793 adults (52% women) from the NuAge study on nutrition and successful aging. Subjects aged 67 to 84 years in relatively good health were recruited from the Québec Medicare Database. Sociodemographic, affective, and cognitive data, health conditions, perceived physical health and functional status, dietary habits and dietary attributes and community resources were obtained using questionnaires. Body weight and height were measured and body mass index (BMI) was calculated. Three non-consecutive 24-hour diet recalls were collected at recruitment. DQ, assessed using the Canadian Healthy Eating Index (C-HEI, /100), was computed on the mean intakes from the diet recalls. Analyses were stratified by gender. Variables significantly related to DQ in bivariate analyses (p<.05) were entered into backward stepwise multiple regression analyses. RESULTS: Among men, the final model showed higher education (ß=0.23, p=.01), diet knowledge (ß=0.96, p<.0001), number of daily meals (ß=1.91, p=.02) and perceived physical health (ß=0.06, p=.01) to be positive determinants of DQ, whereas alcohol consumption (ß=-2.25, p=.05), wearing dentures (ß=-2.31, p=.01) and eating regularly in restaurants (ß=-1.65, p=.03) were negative determinants of DQ (adjusted R2 = 13.7%). Among women, higher education (ß=0.29, p=.002), diet knowledge (ß=0.54, p=.002), number of daily meals (ß=3.61, p<.0001), and hunger (ß=0.61, p<.0001) were positive determinants of global DQ; greater BMI (ß=-0.16, p=.03) and chewing problems (ß=-0.48, p=.03) were negative determinants of DQ (adjusted R2 = 7.8%). DISCUSSION: These results point to several key factors influencing global DQ in older adults and also show gender-based differences. More research must be done to better understand how these factors change with aging and exert their impact on diet, particularly since variance in DQ was largely unexplained. As diet knowledge was an independent predictor for both genders, targeted, sustainable interventions are needed to ensure good diet quality as people age.

Challenges in managing the diet of older adults with early-stage Alzheimer dementia: a caregiver perspective.

UNLABELLED: Caregivers (CG) of older adults suffering from Alzheimer disease (AD) are confronted by many challenges when caring for their family member; these include dietary management. OBJECTIVES: To identify difficulties in dietary management encountered by CG taking part in the Nutrition Intervention Study (NIS), and to gather their opinions on the intervention. DESIGN, SETTING AND PARTICIPANTS: Thirty-three CG of individuals with AD from the NIS intervention group were contacted. Individual interviews were conducted and analyzed using qualitative data analysis, and themes around challenges related to dietary practices experienced by CG were identified. RESULTS: Twenty-four CG were interviewed; 58% were aged 70 and older and 58% were the patient's spouse. Three major thematic categories emerged: 1. Dietary challenges and coping strategies used by CG; 2. CGs' opinion about the NIS; 3. CG interest in participating in a nutrition education support service. Changes in food habits and increasing dependency on the CG were the major themes related to dietary challenges. CONCLUSION: A better understanding of the CG's experience is essential for the development of nutrition interventions adapted to the needs of older adults with AD and their CG.

Dietary intervention in older adults with early-stage Alzheimer dementia: early lessons learned.

In older adults, an adequate diet depends on their ability to procure and prepare food and eat independently or the availability of dietary assistance when needed. Inadequate food intake or increased nutritional requirements lead to poor nutritional status, which is considered a key determinant of morbidity, increased risk of infection, and mortality in elderly individuals. Weight loss among seniors also heralds increased morbidity and mortality. Dietary behaviour disorders affecting food consumption, nutrition status and maintenance of body weight are common in older adults, and have a substantial impact on nutritional status and quality of life among older adults with Alzheimer Dementia (AD). The Nutrition Intervention Study (NIS) is ongoing. It employs a quasi-experimental pre-post intervention design in physically-well, community-dwelling early stage AD patients aged 70 y or older. To date, 34 intervention group patients and 25 control group participants have been recruited with their primary caregivers (CG) from 6 hospital-based memory and geriatric clinics in Montreal. The NIS uses clinical dietetics principles to develop and offer tailored dietary strategies to patients and their CG. This paper reports on the application of dietary intervention strategies in two intervention group participants; one was deemed successful while the other was considered unsuccessful. The report documents challenges encountered in assessing and counselling this clientele, and seeks to explain the outcome of intervention in these patients.

Determinants of diet quality among Quebecers aged 55-74.

OBJECTIVES: Sociodemographic, lifestyle and dietary characteristics were studied to gain insights into determinants of total diet quality and diversity in a weighted sample of 460 participants aged 55-74 (53% female) from the 1990 Enqu te qu b coise sur la nutrition (EQN) dataset. METHODS: Dietary data consisted of an interviewer-administered 24-hour recall and food frequency questionnaire, and a self-administered questionnaire on dietary behaviours, attitudes and perceptions. 24-hour recall data were coded into food groups as described in Canada's Food Guide for Healthy Eating. Diet quality was scored using the categorical Dietary Diversity Score (DDS, range 0-4) and continuous Dietary Adequacy Score (DAS, range 0-18). A second nonconsecutive recall (10% of subjects) permitted correction of food group portions for intraindividual variability and subsequent calculation and validation of usual DDS and DAS. Relationships were examined between the scores and independent variables. Forward leastwise logistic regession (DDS) and stepwise multiple regression (DAS) analyses were conducted with independent variables showing significant bivariate relationships. RESULTS: Among men, breakfast consumption and eating commercially-prepared meals were positively associated with usual DDS, but poor social support and supplement use negatively predicted this score. Eating fewer than 3 meals daily, smoking, and dietary supplement use were negative predictors of usual DAS (r2=0.155). Among women, eating commercial foods was a negative predictor of usual DDS, as was preferring overweight to depriving themselves of favourite foods. Reporting that health concerns influenced food choices and disagreeing with the statement that effort is needed to have a nice body were positive determinants of usual DAS in women. On the other hand, eating fewer than 3 meals daily negatively predicted this dietary index (r2 = 0.162). CONCLUSIONS: Gender differences in predictors of diet quality suggest the need to target nutrition health promotion to the needs of older men and women to encourage optimal eating habits.

A case-control study of breast cancer and dietary intake of individual fatty acids and antioxidants in Montreal, Canada.

This case-control study was conducted among French-Canadians to assess the association between breast cancer risk and specific fatty acids, and to investigate if breast cancer risk associated with individual polyunsaturated fatty acids differs in regard to antioxidant intakes. A total of 414 cases and 429 population-based controls were interviewed between 1989 and 1993. Dietary intake was assessed by a food-frequency questionnaire. No overall association was found between specific fatty acids and breast cancer risk, after adjustment for risk factors and total energy intake. In postmenopausal women with low vitamin E intake, there was an inverse and dose-dependent relationship between arachidonic acid and breast cancer risk [odds ratio (OR)=0.41; 95% confidence interval (CI) (0.20-0.82); P=0.02], while those with high vitamin E intake exhibited a significantly elevated risk [OR=2.46; 95% CI (1.12-5.39); P=0.024] when comparing the upper to the lower quartiles. The possible role of the interaction effect between arachidonic acid and vitamin E in breast cancer risk requires further investigation.

Specific fatty acids and human colorectal cancer: an overview.

BACKGROUND: Evidence suggests that dietary fats are associated with risk of colorectal cancer. The effect of fats depends not only on the quantity, but also on their composition in specific fatty acids. Moreover, fats are peroxidizable, and peroxidation products as well as antioxidants play a role in the pathogenic process of colorectal cancer. METHODS: The published literature was reviewed for the relationship between dietary intake or concentration of specific fatty acids in adipose tissue, erythrocytes, plasma or feces in relation to colorectal cancer. RESULTS: Increased concentrations of short-chain fatty acids (SCFAs) and eicosanopentaenoic acid (EPA) seem to protect against colorectal cancer. Increased concentrations of medium-chain fatty acids (MCFAs) and arachidonic acid (AA) might be associated with increased risk. Long-chain saturated fatty acids (LCSFAs) seem unrelated to colorectal cancer, while the associations between monounsaturated fatty acids (MUFAs), trans fatty acids, polyunsaturated fatty acids (PUFAs) such as linoleic acid (LA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), omega-3/omega-6 ratio and colorectal cancer are unconvincing. CONCLUSIONS: It is suggested that the substitution of food with high MCFAs and AA content by a SCFAs- and EPA-rich diet may contribute to reduced risk of colorectal cancer.

Employee reactions to the introduction of a bulk food distribution system in a nursing home.

Decentralized bulk food distribution was implemented in a nursing home. Employees working with elderly residents with dementia were asked their opinion of the impact of the new system on residents and workload. A convenience sample of 24 employees (57% of the staff) completed a 31-item, self-administered Likert-scale questionnaire that allowed open-ended comments. Responses were subjected to descriptive quantitative analysis, and a qualitative approach was used to explore themes that emerged in comments. Qualitative analysis indicated that 52% of responses were negative in tone, 30% were positive, and 18% were neutral. Initially, three categories of comments emerged, with specific multiple themes related to the residents (41%), the employees (37%), or the food-service system (22%). Most comments in the employee category were negative, and suggested that the decentralized food-service system caused hardship for the staff. This problem was resolved by adding one staff-hour at the midday meal. One year later, an abbreviated repeat survey of 29 employees revealed adaptation and general acceptance of the system. Because a motivated patient care staff is essential to the successful feeding of nursing home residents with dementia, employees' concerns must be considered when operational changes are planned.

Anthropometric changes over 5 years in elderly Canadians by age, gender, and cognitive status.

BACKGROUND: Numerous changes in body composition occur with aging. This study reports on secondary analyses of data from a subsample of institutionalized and free-living elderly Canadians taking part in both phases of the Canadian Study of Health and Aging (CSHA-1 and CHSA-2; n = 10,263) to document and examine correlates of the evolution of anthropometric characteristics over a 5-year period. METHODS: In CSHA-1, community-dwelling (n = 1464) and institutionalized (n = 963) participants' height and weight were measured in clinics. Surviving participants were remeasured in CSHA-2; valid data were available for 487 community-dwelling respondents (66.9% of those seen in clinics in CSHA-2) and 140 institutionalized participants (46.9% of those reassessed). Body mass index (BMI = weight [kg]/height [m(2)]) was calculated. Paired t tests were used to test changes over the interval, and repeated-measures multivariate analysis of variance was used to examine the extent of differences within and across categories. RESULTS: The average weight loss between study phases in community-dwelling and institutionalized participants was approximately 2 kg (p <.001). In institutions, this was statistically significant in most stratification categories, as was the case in community-dwelling participants (by gender, age, dementia screening score, and cognitive diagnosis). Among those who were cognitively intact, the greatest weight losses occurred in participants under 90 years old and in those aged 70 to 79 years with a diagnosis of dementia (p <.01). Stature decreased more in institutionalized (2 cm) than in community-dwelling participants (1.4 cm). In institutions, this was significant among the oldest men (p <.005), while in the community there were no differences in the extent of height lost in all stratification categories. The average BMI was largely stable. CONCLUSIONS: Body weight and stature declined with aging among elderly Canadian CSHA participants, particularly in the very old and those with dementia. Such longitudinal anthropometric data are needed along with information on dietary intakes, and medical, cognitive, and functional measures to plan interventions geared to maximizing nutritional and overall health in the elderly population, whatever their cognitive status.

Weight change, nutritional risk and its determinants among cognitively intact and demented elderly Canadians.

Nutritional risk and its predictors were assessed by evaluating longitudinal changes in body weight using data collected from elderly community-dwelling and institutionalized Canadians who participated in both phases of the Canadian Study of Health and Aging, CSHA (n = 10,263). Change in body weight (% initial weight) was examined over a 5-year interval in 584 community and 237 institutionalized participants, and its predictors tested in multiple and logistic regression analyses. Average weight at CSHA-2 was 97% of initial weight at CSHA-1. Values were lower in those over 90 years and the demented. Increasing frailty in a 7-point scale (beta = -1.23, p = 0.04) predicted weight loss in institutional participants, as did difficulty in eating unaided (beta = 4.24, p < 0.001) and reported loss of interest in life (beta = 2.22, p < 0.001) among community subjects. Some 16% in institutions and 9% in the community were at moderate/severe nutritional risk, disproportionately represented by the oldest subjects and the demented. These analyses support the importance of assessing dietary intakes, anthropometrics, well-being and environmental predictors of aging in the elderly.

Absence of nutritional or clinical consequences of decentralized bulk food portioning in elderly nursing home residents with dementia in Montreal.

OBJECTIVES: To evaluate the nutritional and clinical consequences of changing from a centralized food delivery system to decentralized bulk food portioning; a system in which meal portioning occurs on residents' floors of a nursing home. DESIGN: A pilot study with a pre-post design SUBJECTS/SETTING: The study took place on one floor of a home for elderly persons with dementia. Of the 34 residents, 22 (1 man) participated in this study. Average age was 82 years (range = 55 to 94 years). Nutritional status was verified before introduction of the bulk food portioning system by 3 nonconsecutive days of observed food intakes, anthropometric measurements (height, weight, triceps skinfold thickness, mid-upper-arm circumference), and biochemical parameters (albumin, lymphocytes, glucose, sodium, potassium, transferrin, vitamin B-12, folate, hemoglobin). Trained dietitians collected the dietary and anthropometric data and validated the food intake estimates and anthropometric measurements. Data were also collected 10 weeks after implementation of the new food distribution system. STATISTICAL ANALYSES PERFORMED: Paired t tests adjusted by a Bonferroni correction assessed differences between values measured before and after introduction of the new food distribution system. RESULTS: Average food consumption increased substantially and significantly after introduction of the bulk food portioning system. Mean energy intakes rose from 1,555 to 1,924 kcal/day and most other nutrients also increased, many significantly, but there were no changes in anthropometric values or biochemical parameters, except for albumin level which decreased to the lower normal limit. APPLICATIONS: Portioning of food in the residents' dining room simulates a homelike atmosphere thereby encouraging increased food consumption. With well-trained and enthusiastic staff, this system could contribute to improved nutritional status in the very elderly, even those who have dementia. Dietitians have a key role to play in overseeing residents' nutritional needs and in training, supervising, and motivating foodservice personnel.

Validity of self-reported height and weight estimates in cognitively-intact and impaired elderly individuals.

OBJECTIVE: A high prevalence of undernutrition has been observed in the elderly, particularly in cognitively impaired or demented individuals. Self-reported height and weight were tested as simple and non-invasive methods to efficiently screen individuals at risk. DESIGN: Cross-sectional study. PARTICIPANTS: A subset of subjects (n=465) participating in the longitudinal follow-up phase of the Canadian Study of Health and Aging (CSHA) and comprising cognitively intact and impaired individuals as well as demented subjects. MEASUREMENTS: Self-reported values of height and weight were compared to direct standard measurements using Pearson's correlation coefficients and linear regressions by cognitive status. Estimation bias was determined using paired Student t-tests. Sensitivity and specificity of body mass index (BMI) derived from self-reported data were calculated. RESULTS: Self-reported and measured weights were highly correlated (r>.90) in all three categories of cognitive status. A tendency to underestimate their weight was observed in overweight women. Correlations of recalled to measured height were excellent in normal (r=.91) and good in cognitively impaired (r=.86) and demented (r=.85) subjects. A systematic overestimation of recalled height was observed, particularly among individuals of short stature. Self-reported BMI showed excellent sensitivity (>93%) in detecting underweight individuals in all three categories. CONCLUSION: Self-reported height and weight data can be obtained in normal and cognitively-impaired elderly persons as well as in mild or moderate cases of dementia and can be used as a valid tool to screen for risk of undernutrition.

Exploratory assessment of fish consumption among Asian-origin sportfishers on the St. Lawrence river in the montreal region.

An exploratory survey was undertaken in the fall 1995 open-water fishing season with nine Bangladeshi and nine Vietnamese-origin sportfishers. Survey methodology and techniques of dietary and fish intake assessment were adapted to the cultural values and second language of each community. A 70-item instrument assessing sportfishing practices and fish consumption habits was administered by dietitians in participants' homes. Two 24-h diet recalls (aided by photographs taken by the participants) and a fish consumption calendar permitted the assessment of fish intake in the overall dietary context. A fish frequency item addressed consumption of locally available fish species (both sport and market fish) as well as imported frozen or dried species. Annually, Bangladeshi fishers consumed 46.8+/-25.6 sportfish meals, and Vietnamese fishers ate 40. 7+/-35.1 meals. In contrast, Bangladeshis reported greater annual consumption of imported, frozen nonsportfish (76.0+/-40.9 meals), and the Vietnamese ate more ocean than freshwater fish (45.1+/-34.4 ocean fish meals). Fish constituted approximately 19% of all protein foods eaten among the Bangladeshi fishers and 10% in the Vietnamese sample. Plasma and erythrocyte eicosapentanoic acid (EPA):arachidonic acid (AA) ratios supported findings from the fish frequency question showing that the two groups of Asian-origin fishers eat differing quantities of different fish species and that Asian-origin sportfishers-particularly the Bangladeshis-eat fish overall more frequently and in greater variety and quantity than francophone Quebecers; species selection appears to be both culturally motivated and influenced by the availability of St. Lawrence sportfish.

Reliability and relative validity of fish consumption data obtained in an exposure assessment study among Montreal-area sportfishers.

A two-season exercise was undertaken in 29 high-level sportfish consumers to evaluate the reliability and accuracy of study instruments. Fishers were invited to participate after completing the main study interview (Time 1) in fall 1995 or winter 1996. Over a 4-week period, they provided a nonconsecutive 7-day weighed food record, kept a fish consumption calendar, and responded to a shortened version of the Time 1 instrument at the end of this period (Time 2). A second blood sample (at Time 2) was analyzed for whole blood mercury (Hg) and the omega-3 fatty acids eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) in plasma and erythrocytes. Identical questions were compared in the Time 1 and Time 2 instruments. Reported sportfish consumption assessed by the different instruments was subjected to nutrient analysis. Three estimates of exposure to the target substances were derived from the dietary intake estimates and correlated with their respective Time 2 plasma (EPA, DHA) or blood (Hg) values, and with a kinetically derived interval-specific plasma/blood uptake value. Remarkable similarities were observed for the data derived from like questions in the Time 1 and 2 questionnaires in both seasons. However, frank discrepancies between some portion size estimates and measured values may signal cause for concern. The strongest correlations between the Time 2 plasma DHA and EPA, and blood Hg, and the three exposure indices emerged between estimates of retrospective DHA intake and DHA fish calendar values and their corresponding Time 2 plasma levels, and for Hg estimated both retrospectively and from the fish consumption calendar and correlated with Time 2 blood Hg, especially in the winter 1996 dataset. Overall, the results suggest that the main study instrument provides a reliable and relatively accurate indication of sportfishers' fishing practices, species selection, and sportfish consumption habits.

Fish consumption and contaminant exposure among Montreal-area sportfishers: pilot study.

A 1995 pilot study assessed sport fish consumption and contaminant exposure among Montreal-area residents fishing the frozen St. Lawrence River. Interviews conducted among 223 ice fishers met on-site were used to create an index of estimated exposure to fish-borne contaminants. A second-stage assessment of sport fish consumption and tissue contaminant burdens included 25 interviewees at the highest level of estimated contaminant exposure (of 38, or 66% of those solicited) and 15 low-exposure fishers (of 41, or 37% of those solicited). High-level fisher-consumers reported eating 0. 92+/-0.99 sport fish meals/week during the previous 3 weeks compared to 0.38+/-0.21 (P<0.05) for the low-level group. Based on the product of consumption frequency times mass of sport fish meals consumed, high-level consumers ate a mean of 18.3 kg of sport fish annually versus 3.3 kg for the low-level consumers. Tissue contaminant assessments showed significant (P<0.05) groupwise differences: 0-1 cm hair mercury (median 0.73 microgram/g for the high versus 0.23 microgram/g for the low group), lipid-adjusted plasma PCB congeners (Aroclor 1260: median 0.77 microgram/g versus 0.47 microgram/g), and lipid-adjusted plasma DDE (median 0.35 microgram/g versus 0.26 microgram/g). No participant had a hair mercury or plasma DDE concentration above Health Canada recommendations but 2/25 high-level participants (8%) had plasma Aroclor 1260 concentrations above recommended limits. The results of this pilot study suggest that a small number of Montreal-area sportfishers consume their catch as often as three times weekly and that those consuming sport fish frequently have significantly higher tissue levels of mercury, PCBs, and DDE than do infrequent consumers. On the other hand, compared to other groups in Quebec, such as the Inuit or commercial fishers on the North Shore of the Gulf of St. Lawrence, Montreal-area sportfishers eat less fish and have lower tissue concentrations of fish-related contaminants.

Contaminant exposure in Montrealers of Asian origin fishing the St. Lawrence River: exploratory assessment.

Fishing and fish consumption are widely practiced among members of certain ethnocultural groups. Informal assessment led us to ascribe high levels of consumption of locally caught sportfish to Montrealers of Asian origin and to hypothesize that their choices of species and fish organs differ from those of the majority group. An exploratory assessment of contaminant bioindicators reflective of St. Lawrence River fish consumption was conducted in late 1995 among nine Vietnamese and nine Bangladeshi Montreal sportfishers identified by community contacts. Vietnamese participants, six men and three women, were 27-70 (median 36) years of age and had immigrated to Canada 3-20 (median 7) years earlier. In contrast, the nine Bangladeshi males aged 28-41 (median 34) years had been in Canada for 2-13 (median 4) years. Bio-indicator concentrations among Bangladeshi and Vietnamese participants are compared to those found for majority-community Montreal-area high-level consumers recruited on the St. Lawrence River during winter 1995. All results are presented as the median and 90th percentile. Hair mercury concentrations were higher for both Vietnamese (1.2, 4.6 microgram/g) and Bangladeshis (1.1, 2.3 microgram/g) than for majority-community sportfishers (0.7, 1.9 microgram/g). Certain organochlorine levels, specifically total PCB (estimated by plasma Aroclor 1260), p,p'-DDT, p,p'-DDE, and B-BHC, were highest in the Bangladeshis compared to Vietnamese and to majority-community sportfishers. In contrast, plasma levels of other pesticides were low in all three groups, including mirex, chlordane, and cis-nonachlor. A correlation between plasma p,p'-DDT levels and recency of arrival in Canada was found for the Bangladeshis. These data suggest a distinct pattern of tissue organochlorines, which we postulate relates to exposure prior to arrival in Canada and perhaps to the ongoing consumption of foods (other than St. Lawrence River sportfish) specific to these groups.