Association between whole blood mercury and glucose intolerance among adult Inuit in Greenland.

OBJECTIVES: The Arctic diet is partly constituted by traditional food characterized by top predator animals such as whales, walrus, and seals with high mercury content. Mercury exposure has been associated with glucose intolerance in Western populations. We studied the association between whole blood mercury and glucose intolerance in a highly exposed non-Western population METHODS: Cross-sectional study of 2640 Inuit (18+ years) with information on ancestry, smoking, waist circumference, total energy intake, and physical activity. Mercury, fasting- and 2-h plasma glucose, insulin, and c-peptide were measured in blood. Fasting participants without diabetes were classified into normal glucose tolerance, impaired glucose tolerance, impaired fasting glycemia, or type 2 diabetes. We calculated hepatic insulin resistance with homoeostatic model assessment - insulin resistance index, peripheral insulin sensitivity by ISI0,120., and relative beta cell function by c-peptide/insulin ratio. We conducted adjusted linear- and logistic regression analyses. RESULTS: For an increase in whole blood mercury of 5 µg/L we found a positive association with fasting glucose [% change=0.25 (95% CI: 0.20; 0.30); p<0.001], and 2-h glucose [% change=0.23 (95% CI: 0.05; 0.40); p=0.01]. Mercury was weakly associated with impaired fasting glycemia [OR=1.03 (95% CI: 1.02; 1.05)], and type 2 diabetes [OR=1.02 (95% CI: 1.01; 1.04)]. CONCLUSION: While the study found a weak but statistically significant association between whole blood mercury and both impaired fasting glycemia and type 2 diabetes, no associations were found with measures of underlying disturbances in glucose homoeostasis.

Influence of polyunsaturated fatty acids on blood pressure, resting heart rate and heart rate variability among French Polynesians.

OBJECTIVE: To analyze the associations between marine n-3 polyunsaturated fatty acids (PUFAs) and blood pressure (BP), resting heart rate (HR), and heart rate variability (HRV) in a population highly exposed to methylmercury through the diet. METHODS: Concentrations of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in erythrocytes membranes were measured in 180 French Polynesian adults (≥18 years) residing in Tubuai, which is a community with a traditional lifestyle, or Papeete, which has a modern lifestyle. HRV was measured using a 2-hour ambulatory electrocardiogram (Holter). Resting HR and BP were measured using standardized protocols and pulse pressure (PP) was calculated as systolic BP - diastolic BP. The associations between n-3 PUFAs and the dependent variables were studied using simple and multiple linear regressions. RESULTS: Increasing DHA concentration was associated with lower resting HR (ß = -2.57, p = 0.005) and diastolic BP (ß = -1.96, p = 0.05) and higher HRV in multivariable models. Specifically, DHA was associated with high frequency (HF; ß = 0.19, p = 0.02) and the square root of the mean squared differences of successive R-R intervals (difference between two consecutive R waves; rMSSD; ß = 0.08, p = 0.03), which are specific indices of the parasympathetic activity of the autonomic nervous system. CONCLUSION: DHA was associated with lower BP and resting HR and higher HRV among French Polynesians who are also exposed to high methylmercury levels.

Association between methylmercury and cardiovascular risk factors in a native population of Quebec (Canada): a retrospective evaluation.

BACKGROUND: Epidemiological evidence suggests a negative impact of methylmercury (MeHg) on cardiovascular risk factors such as blood pressure (BP) and heart rate (HR). This issue is of concern in Arctic populations such as in the Inuit of Nunavik since this contaminant is accumulated in fish and marine mammals, which still represent the subsistence diet of this population. OBJECTIVE: We examined the associations between MeHg and BP and resting HR among Inuit adults. METHODS: The "Santé Quebec" health survey was conducted in 1992 in the 14 villages of Nunavik and a complete set of data was obtained for 313 Inuit adults≥18 years. Blood samples were collected in order to determine total mercury, lead, total polychlorinated biphenyls (PCBs), n-3 polyunsaturated fatty acids (PUFAs), fasting glucose and lipid profile while socio-demographic variables were obtained through questionnaires. Anthropometric measurements as well as BP and resting HR were obtained using standardised protocols. Pulse pressure (PP: systolic BP minus diastolic BP) was also calculated. Multiple linear regression was used in order to determine the change in the dependent variables associated with the quartiles of MeHg concentration, taking the quartile 1 as reference. RESULTS: The mean age of the participants was 38±14 years and the sample was composed of 132 men (42.2%) and 181 women (57.8%). MeHg geometric mean was 15.4 µg/L (95%CI: 13.9-17.0) and levels ranged from 0.8 to 112.0 µg/L. Resting HR increased linearly across quartiles of blood MeHg concentration after adjusting for confounders (p for trend=0.02). An increase of 6.9 beats per minute (bpm) between the 4th and 1st quartile was observed after adjusting for confounders. No significant association was observed between blood MeHg and systolic BP, diastolic BP or PP. CONCLUSIONS: MeHg was associated with increasing resting HR after considering traditional risk factors as well as other contaminants (lead and total PCBs) and n-3 PUFAs. In contrast, no significant association with blood pressure was observed in this study.

Exposure to persistent organic pollutants and risk of hypertension among Inuit from Greenland.

BACKGROUND: Exposure to persistent organic pollutants (POPs) is of concern in Arctic populations since these contaminants accumulate in fish and marine mammals, which is an important part of the traditional diet of these populations. Epidemiological and experimental studies have reported significant associations between POPs and increased blood pressure (BP) in populations with different degrees of exposure. OBJECTIVE: We aimed to assess the risk of hypertension related to increasing levels of polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides. METHODS: Fifteen PCBs and 11 OC pesticides or their metabolites were determined in plasma of 1614 Inuit adults ≥ 18 years living in 9 towns and 13 villages in Greenland. BP was measured using a standardized protocol. The risk of hypertension was estimated through logistic regression using POPs as continuous variables (log-transformed). Hypertension was defined as systolic BP ≥ 140 mm Hg, diastolic BP ≥ 90 mm Hg and/or antihypertensive treatment. RESULTS: Overall, the odd ratios (ORs) of hypertension were not statistically significant for dioxin-like PCBs, non-dioxin-like PCBs and OC pesticides after adjusting for confounders. Once the analyses were stratified by age category (18-39 and ≥ 40 years), increased risk of hypertension was observed for total dioxin-like PCBs among the youngest [OR: 1.34 (95% CI: 1.03-1.74)] while a borderline protective effect was observed for total non-dioxin-like PCBs [OR: 0.81 (95% CI: 0.66-0.99)] among the oldest. Higher risk of hypertension was also associated with increasing p,p'-dichlorodiphenyltrichloroethane (DDT) concentrations among the youngest [OR: 1.42 (95% CI: 1.08-1.85)]. CONCLUSION: Overall, no significant associations were observed between PCBs, OC pesticides and blood pressure in this highly exposed population although the associations differed by age category.

Influence of mercury exposure on blood pressure, resting heart rate and heart rate variability in French Polynesians: a cross-sectional study.

BACKGROUND: Populations which diet is rich in seafood are highly exposed to contaminants such as mercury, which could affect cardiovascular risk factors OBJECTIVE: To assess the associations between mercury and blood pressure (BP), resting heart rate (HR) and HR variability (HRV) among French Polynesians METHODS: Data were collected among 180 adults (≥ 18 years) and 101 teenagers (12-17 years). HRV was measured using a two-hour ambulatory electrocardiogram (Holter) and BP was measured using a standardized protocol. The association between mercury and HRV and BP parameters was studied using analysis of variance (ANOVA) and analysis of covariance (ANCOVA) RESULTS: Among teenagers, the high frequency (HF) decreased between the 2nd and 3rd tertile (380 vs. 204 ms2, p = 0.03) and a similar pattern was observed for the square root of the mean squared differences of successive R-R intervals (rMSSD) (43 vs. 30 ms, p = 0.005) after adjusting for confounders. In addition, the ratio low/high frequency (LF/HF) increased between the 2nd and 3rd tertile (2.3 vs. 3.0, p = 0.04). Among adults, the standard deviation of R-R intervals (SDNN) tended to decrease between the 1st and 2nd tertile (84 vs. 75 ms, p = 0.069) after adjusting for confounders. Furthermore, diastolic BP tended to increase between the 2nd and 3rd tertile (86 vs. 91 mm Hg, p = 0.09). No significant difference was observed in resting HR or pulse pressure (PP) CONCLUSIONS: Mercury was associated with decreased HRV among French Polynesian teenagers while no significant association was observed with resting HR, BP, or PP among teenagers or adults.

Cardiac autonomic activity and blood pressure among Nunavik Inuit adults exposed to environmental mercury: a cross-sectional study.

BACKGROUND: Mercury is a contaminant that reaches high levels in Nunavik (North of Quebec). It is transformed into methylmercury (MeHg) and accumulated in marine mammals and predator fish, an important part of the traditional Inuit diet. MeHg has been suggested to affect BP in adults and children while the influence on HRV has only been studied in children. We aimed to assess the impact of MeHg levels on HRV and BP in Inuit adults from Nunavik. METHODS: In the fall of 2004, the <> Health Survey was conducted in Nunavik (Quebec, Canada) and information on HRV was collected among 280 adults aged 40 years and older. Indicators of the time and frequency domains of HRV were derived from a 2-hour Holter recording. BP was measured according to the Canadian Coalition for High Blood Pressure technique. Pulse pressure (PP) was the difference between systolic (SBP) and diastolic blood pressure (DBP). Blood mercury concentration was used as exposure biomarker. Statistical analysis was conducted through linear regression and multivariable linear regression was used to control for confounders. RESULTS: Mercury was negatively correlated with low frequency (LF) (r = -0.18; p = 0.02), the standard deviation of RR intervals (SDNN) (r = -0.14; p = 0.047) and the coefficient of variation of RR intervals (CVRR) (r = -0.18; p = 0.011) while correlations with other HRV parameters did not reach statistical significance. After adjusting for confounders, the association with LF (beta = -0.006; p = 0.93) became non significant. However, the association with SDANN became statistically significant (beta = -0.086; p = 0.026) and CVRR tended to decrease with blood mercury concentrations (beta = -0.057; p = 0.056). Mercury was positively correlated with SBP (r = 0.25; p < 0.0001) and PP (r = 0.33; p < 0.0001). After adjusting for confounders, these associations remained statistically significant (beta SBP = 4.77; p = 0.01 and beta PP = 3.40; p = 0.0036). Moreover, most of the HRV parameters correlated well with BP although SBP the best before adjustment for mercury exposure. CONCLUSION: The results of this study suggest a deleterious impact of mercury on BP and HRV in adults. SBP and PP increased with blood mercury concentrations while SDANN decreased with blood mercury concentrations.

Five shared decision-making tools in 5 months: use of rapid reviews to develop decision boxes for seniors living with dementia and their caregivers.

BACKGROUND: Decision support tools build upon comprehensive and timely syntheses of literature. Rapid reviews may allow supporting their development by omitting certain components of traditional systematic reviews. We thus aimed to describe a rapid review approach underlying the development of decision support tools, i.e., five decision boxes (DB) for shared decision-making between seniors living with dementia, their caregivers, and healthcare providers. METHOD: We included studies based on PICO questions (Participant, Intervention, Comparison, Outcome) describing each of the five specific decision. We gave priority to higher quality evidence (e.g., systematic reviews). For each DB, we first identified secondary sources of literature, namely, clinical summaries, clinical practice guidelines, and systematic reviews. After an initial extraction, we searched for primary studies in academic databases and grey literature to fill gaps in evidence. We extracted study designs, sample sizes, populations, and probabilities of benefits/harms of the health options. A single reviewer conducted the literature search and study selection. The data extracted by one reviewer was verified by a second experienced reviewer. Two reviewers assessed the quality of the evidence. We converted all probabilities into absolute risks for ease of understanding. Two to five experts validated the content of each DB. We conducted descriptive statistical analyses on the review processes and resources required. RESULTS: The approach allowed screening of a limited number of references (range: 104 to 406/review). For each review, we included 15 to 26 studies, 2 to 10 health options, 11 to 62 health outcomes and we conducted 9 to 47 quality assessments. A team of ten reviewers with varying levels of expertise was supported at specific steps by an information specialist, a biostatistician, and a graphic designer. The time required to complete a rapid review varied from 7 to 31 weeks per review (mean ± SD, 19 ± 10 weeks). Data extraction required the most time (8 ± 6.8 weeks). The average estimated cost of a rapid review was C$11,646 (SD = C$10,914). CONCLUSIONS: This approach enabled the development of clinical tools more rapidly than with a traditional systematic review. Future studies should evaluate the applicability of this approach to other teams/tools.

The ethnoepidemiology of obesity.

The prevalence of overweight and obesity varies significantly across ethnic groups and among aboriginal people in Canada and appears to be increasing overall in children and youth, which will have significant health consequences in the future. Individual health behaviours, genetic predisposition, and community-level factors all contribute to the high burden of overweight and obesity across communities in Canada. Preliminary studies indicate that individuals who live in neighbourhoods in Canada with increased walkability, fewer fast food outlets, and higher socioeconomic status have lower rates of overweight/obesity when compared with other neighbourhoods. However, more research is required to understand the impact of community level factors on overweight/obesity trends in Canadian ethnic groups, including children and youth, and aboriginal people.

Methylmercury exposure, PON1 gene variants and serum paraoxonase activity in Eastern James Bay Cree adults.

There is growing evidence that cardiovascular health can be affected by exposure to methylmercury (MeHg), by a mechanism involving oxidative stress. Paraoxonase 1 (PON1) is a high-density lipoprotein-bound enzyme that hydrolyzes toxic oxidized lipids and protects against cardiovascular diseases. Evidence from in vitro studies indicates that MeHg can inhibit PON1 activity but little is known regarding this effect in humans. We investigated whether increased blood mercury levels are associated with decreased serum PON1 activity in Cree people who are exposed to MeHg by fish consumption. We conducted a multi-community study of 881 Cree adults living in Eastern James Bay communities (Canada). Multivariate analyses considered sociodemographic, anthropometric, clinical, dietary and lifestyle variables and six PON1 gene variants (rs705379 (-108C/T), rs662 (Q192R), rs854560 (L55M), rs854572 (-909C/G), rs854571 (-832C/T) and rs705381 (-162C/T)). In a multiple regression model adjusted for all potential confounding factors and the rs854560 PON1 variant, a statistically significant MeHg*rs705379 interaction was observed. Blood mercury levels were inversely associated with serum PON1 activities in individual homozygous for the -108T allele (P=0.009). Our results suggest a gene-environment interaction between the rs705379 polymorphism and MeHg exposure on PON1 activity levels in this aboriginal population. This finding will need to be replicated in other population studies.

Associations between plasma persistent organic pollutant levels and blood pressure in Inuit adults from Nunavik.

BACKGROUND: Recent evidence suggests that exposure to persistent organic pollutants (POPs) increases the risk of hypertension in environmentally exposed populations. High POP levels have been detected in Arctic populations and the exposure is related to high consumption of fish and marine mammals, which represent the traditional diet of these populations. OBJECTIVE: We examined the associations between polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and hypertension among Inuit from Nunavik (Quebec, Canada). METHODS: A complete set of data was obtained for 315 Inuit≥18years who participated in the "Santé Québec" health survey that was conducted in the 14 villages of Nunavik in 1992. Fourteen polychlorinated biphenyls (PCBs) and 8 OC pesticides or their metabolites were measured in plasma samples using gas chromatography with electron capture detection. Blood pressure (BP) was measured using a standardized protocol and information regarding anti-hypertensive medication was obtained through questionnaires. The associations between log-transformed POPs and hypertension (systolic BP≥140mmHg, diastolic BP≥90mmHg or anti-hypertensive medication) were analyzed using multiple logistic regressions. RESULTS: Total PCBs as well as the sum of non-dioxin-like PCBs were significantly associated with higher risk of hypertension. Furthermore, the risk of hypertension increased with higher plasma concentrations of congeners 101, 105, 138 and 187. Models adjusted for BP risk factors became significant after including n-3 polyunsaturated fatty acids (PUFAs) and further adjustment for lead and mercury did not change the results. Regarding OC pesticides, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) was associated with increased risk of hypertension while inverse associations were observed with p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), ß-hexachlorocyclohexane (HCH) and oxychlordane. CONCLUSIONS: Some PCB congeners were associated with higher risk of hypertension in this highly exposed population. Most associations became significant after including n-3 PUFAs in the models. However, the analyses of OC pesticides revealed divergent results, which need to be confirmed in further cohort and experimental studies.

Daily steps threshold to improve cardiovascular disease risk factors during the year after an acute coronary syndrome.

PURPOSE: To evaluate the daily steps threshold associated with improved cardiovascular disease risk factors during the first year following an acute coronary syndrome. METHODS: Subjects (N = 41) were recruited during hospitalization for an acute coronary syndrome. A blinded pedometer with a 7-day memory (NL-2000) was used at baseline, 3, 6, 9, and 12 months following hospitalization. Cardiovascular disease risk factors were measured at baseline, 6, and 12 months after discharge. Subjects who maintained a mean of 7500 steps per day or more at each time period were classified into the active group, whereas those who did not maintain this threshold were classified into the less active group. RESULTS: The active group included 25 subjects, whereas 16 subjects were included in the less active group. Daily steps mean ± SEM was different between groups at 6 and 12 months followup (11 320 ± 3380 vs 5503 ± 1502 and 10 507 ± 2861 vs 6624 ± 3295 steps per day, respectively; both P < .001). Based on the analysis of variance for repeated measures (ANOVA-RM), the active group showed lower triglycerides (P < .01), lower waist circumference (P < .01), and higher high-density lipoprotein-cholesterol (HDL-C) (P = .04) at 12 months. Interaction effects (group × followup) were also significant for HDL-C (P = .01) and triglycerides (P = .01) after adjustment for age, gender, and baseline waist circumference. CONCLUSION: Targeting $7500 daily steps during 1 year may be efficient to maintain lowest waist circumference and to improve lipid profile during the year following an acute coronary syndrome. It could be considered a starting target point to initiate changes in physical activity behavior.

Cardiac autonomic activity and blood pressure among Inuit children exposed to mercury.

BACKGROUND: Studies conducted in the Faeroe Islands and Japan suggest a negative impact of mercury on heart rate variability (HRV) among children while the results regarding blood pressure (BP) are less consistent. OBJECTIVE: To assess the impact of mercury on HRV and BP among Nunavik Inuit children. METHODS: A cohort of 226 children was followed from birth to 11 years old. Mercury concentration in cord blood and in blood and hair at 11 years old were used as markers of prenatal and childhood exposure, respectively. HRV was measured using ambulatory 2 h-Holter monitoring while BP was measured through a standardized protocol. Simple regression was used to assess the relationship of mercury to BP and HRV parameters. Multiple linear regressions were performed adjusting for covariates such as age, sex, birth weight, body mass index (BMI), height, total n-3 fatty acids, polychlorinated biphenyls (PCB 153), lead, selenium and maternal smoking during pregnancy. RESULTS: Median cord blood mercury and blood mercury levels at 11 years old were 81.5 nmoL/L (IQR:45.0­140.0) and 14.5 nmol/L (IQR: 7.5­28.0), respectively. After adjusting for the covariates, child blood mercury was associated with low frequency (LF) (b = 0.21, p = 0.05), the standard deviation of R­R intervals (SDNN) (b = 0.26, p = 0.02), the standard deviation of R­R intervals measured over 5 min periods (SDANN) (b = 0.31, p = 0.01) and the coefficient of variation of R­R intervals (CVRR) (b = 0.06,p = 0.02). No significant association was observed with BP. CONCLUSION: Mercury exposure during childhood seems to affect HRV among Nunavik Inuit children at school age.

Influence of n-3 fatty acids on cardiac autonomic activity among Nunavik Inuit adults.

OBJECTIVES: Inuit from Nunavik (northern Quebec) consume large amounts of fish and marine mammals, which are important sources of n-3 polyunsaturated fatty acids (n-3 PUFAs). These substances have a beneficial impact on heart rate (HR) and heart rate variability (HRV). However, it is unknown if this beneficial impact remains significant in populations with high mercury exposure. The study assessed the impact of n-3 PUFAs (Docosahexaenoic [DHA] and Eicosapentaenoic acid [EPA]) on resting HR and HRV among Nunavik Inuit adults considering mercury and other potential confounders. STUDY DESIGN: Cross-sectional study employing clinical measurements. METHODS: Complete data were collected among 181 adults ≥ 40 years old (109 women and 72 men) living in the 14 coastal villages of Nunavik. Several indices of HRV were derived from a 2-hour Holter monitoring assessment. n-3 PUFAs levels were measured in membrane erythrocytes. Simple linear regression was used to analyse the relationship between n-3 PUFAs levels and resting HR and HRV parameters while multiple linear regressions were carried out to control for confounders. RESULTS: In the overall analyses, EPA was associated with SDANN (ß = 0.07, p = 0.04) and LF norm (ß = -1.84, p = 0.03) after adjusting for confounders. Among women, DHA was associated with resting HR (ß =-1.40, p = 0.03) while EPA was associated with SDNN (ß = 0.08, p = 0.03), SDANN (ß = 0.09, p = 0.02) and resting HR (ß = -2.61, p = 0.002). No significant association was observed in men. CONCLUSIONS: These results suggest a beneficial impact of n-3 PUFAs on resting HR and HRV among Nunavik Inuit women.

Hypertension among the Inuit from Nunavik: should we expect an increase because of obesity?

OBJECTIVES: Because of their recent adoption of a Westernized lifestyle, an increased risk of developing hypertension (HTN) is suspected among Inuit populations. This study aimed to assess the exact prevalence of HTN in Nunavik Inuit and to examine its association with other major risk factors of cardiovascular disease. STUDY DESIGN: A cross-sectional population-based study. METHODS: We analysed biological and anthropometric data and the medical history of 832 Inuit. RESULTS: The overall prevalence of HTN (≥140/90 mmHg or the use of medication) was 19% with no gender difference. Obesity (body mass index [BMI] ≥30 kg/m(2)) was the highest prevalent cardiovascular risk factor (23%), and was significantly associated with HTN (OR for BMI<25 kg/m(2) vs. BMI 30-34 kg/m(2): 7.9 [3.5-17.9]; OR for BMI<25 kg/m(2) vs. BMI ≥35 kg/m(2): 14.4 [5.6-36.7]). An increase in odds of prehypertension (preHTN) (130-139/80-89 mmHg) was also observed as the BMI increased (p for trend, p<0.0001). CONCLUSION: The prevalence of HTN in the Inuit populations has reached values similar to those of their Westernized counterparts. Furthermore, not only HTN but also preHTN states are significantly associated with obesity even after adjusting for confounding variables. These results clearly indicate that HTN is becoming a growing health challenge in Nunavik because of pandemic obesity.

Cardiovascular burden and related risk factors among Nunavik (Quebec) Inuit: insights from baseline findings in the circumpolar Inuit health in transition cohort study.

BACKGROUND: The Inuit are commonly portrayed to be somehow protected from cardiovascular diseases (CVDs) through their traditional lifestyle and diet. However, actual sociocultural transition and related major, modifiable risk factors have scarcely been quantified in the Inuit population. Such knowledge is extremely valuable in terms of public health intervention. METHODS: A total of 887 Inuit residents from Nunavik, Quebec, participated in a cohort study. The estimates presented were derived from anthropometric and biological measurements gathered at the time of recruitment and enhanced by information collected in the medical file of each participant. All estimates were corrected for a complex sampling strategy and bootstrapped to ensure the representativeness of the general Nunavik population. RESULTS: Overall, 19% of Inuit had a disease of the circulatory system according to the International Statistical Classification of Diseases and Related Health Problems, 10th revision. Among all disorders, peripheral circulatory system disease was the most prevalent (9%). Prevalences of ischemic heart disease and cerebrovascular disease were of similar magnitude (2.5%). No significant difference in disease prevalence was noted between sexes. The major modifiable CVD risk factors were smoking (84%), obesity (49%) [corrected] (body mass index of greater than 30 kgm2) and elevated blood pressure (13085 mmHg or greater) (18%). Prevalences were globally higher among women. CONCLUSION: The current belief that the Inuit are protected from CVD is seriously questioned by the results of the present study. Considering the extremely high prevalence of CVD risk factors, a population-based intervention reinforced for women is urgently needed to reduce their risk.

Environmental mercury exposure and blood pressure among Nunavik Inuit adults.

Epidemiological evidence suggests a negative impact of methylmercury on the cardiovascular system, but findings regarding the effect on blood pressure (BP) are not consistent. We aimed to study the impact of mercury levels on BP among Nunavik Inuit adults. The health survey Qanuippitaa? was conducted in Nunavik (northern Quebec, Canada), and data were obtained from 732 Inuit > or = 18 years of age. Anthropometric blood samples, as well as systolic BP and diastolic BP, were assessed. Pulse pressure (systolic BP-diastolic BP) was calculated. Mercury blood concentration was used as a biomarker of recent exposure. Simple relations between mercury and BP parameters were studied by using the Pearson correlation, whereas multiple regressions were performed to control for confounders. Mean age of the participants was 34.3 years (95% CI: 33.6 to 34.9 years). Systolic BP, diastolic BP, and pulse pressure means were 117 mm Hg (95% CI: 116 to 118 mm Hg), 73 mm Hg (95% CI: 72 to 74 mm Hg), and 43 mm Hg (95% CI: 42 to 44 mm Hg), respectively. Mercury mean was 50.2 nmol/L. In multivariable analyses, mercury was associated with systolic BP (beta=2.14; P=0.0004), whereas the association with diastolic BP was near the significance level (beta=0.96; P=0.069). In conclusion, mercury is associated with increasing BP and pulse pressure among Nunavik Inuit adults after considering the effect of fish nutrients (n-3 fatty acids and selenium) and other confounders.