Association of macrosomia with perinatal and postneonatal mortality among First Nations people in Quebec.

BACKGROUND: High prevalence of infant macrosomia (up to 36%, the highest in the world) has been reported in some First Nations communities in the Canadian province of Quebec and the eastern area of the province of Ontario. We aimed to assess whether infant macrosomia was associated with elevated risks of perinatal and postneonatal mortality among First Nations people in Quebec. METHODS: We calculated risk ratios (RRs) of perinatal and postneonatal mortality by birthweight for gestational age, comparing births to First Nations women (n = 5193) versus women whose mother tongue is French (n = 653 424, the majority reference group) in Quebec 1991-2000. RESULTS: The prevalence of infant macrosomia (birthweight for gestational age > 90th percentile) was 27.5% among births to First Nations women, which was 3.3 times (confidence interval [CI] 3.2-3.5) higher than the prevalence (8.3%) among births to women whose mother tongue is French. Risk ratios for perinatal mortality among births to First Nations women were 1.8 (95% CI 1.3-2.5) for births with weight appropriate for gestational age, 4.1 (95% CI 2.4-7.0) for small-for-gestational-age (< 10th percentile) births and < 1 (not significant) for macrosomic births compared to births among women whose mother tongue is French. The RRs for postneonatal mortality were 4.3 (95% CI 2.7-6.7) for infants with appropriate-for-gestational-age birthweight and 8.3 (95% CI 4.0-17.0) for infants with macrosomia. INTERPRETATION: Macrosomia was associated with a generally protective effect against perinatal death, but substantially greater risks of postneonatal death among births to First Nations women in Quebec versus women whose mother tongue is French.

Birth outcomes and infant mortality among First Nations Inuit, and non-Indigenous women by northern versus southern residence, Quebec.

BACKGROUND: In circumpolar countries such as Canada, northern regions represent a unique geographical entity climatically, socioeconomically and environmentally. There is a lack of comparative data on birth outcomes among Indigenous and non-Indigenous subpopulations within northern regions and compared with southern regions. METHODS: A cohort study of all births by maternal mother tongue to residents of northern (2616 First Nations (North American Indians), 2388 Inuit and 5006 non-Indigenous) and southern (2563 First Nations, 810,643 non-Indigenous) Quebec, 1991-2000. RESULTS: Compared with births to southern non-Indigenous mother tongue women, births to northern women of all three mother tongue groups were at substantially elevated risks of infant death (adjusted OR (aOR) 1.7-2.9), especially postneonatal death (aOR 2.2-4.4) after controlling for maternal education, age, marital status and parity. The risk elevation in perinatal death was greater for southern First Nations (aOR 1.6) than for northern First Nations (aOR 1.2). Infant macrosomia was highly prevalent among First Nations in Quebec, especially in the north (31% vs 24% in the south). Within northern regions, Inuit births were at highest risk of preterm delivery (aOR 1.4) and infant death (aOR 1.6). CONCLUSION: All northern infants (First Nations, Inuit or non-Indigenous) were at substantially elevated risk of infant death in Quebec, despite a universal health insurance system. Southern First Nations newborns have not benefited from the more advanced perinatal care facilities in southern regions. Environmental influences may partly account for the very high prevalence of macrosomia among First Nations in northern Quebec.

Individual- and Community-Level Disparities in Birth Outcomes and Infant Mortality among First Nations, Inuit and Other Populations in Quebec.

OBJECTIVE: We assessed individual- and community-level disparities and trends in birth outcomes and infant mortality among First Nations (North American Indians) and Inuit versus other populations in Quebec, Canada. METHODS: A retrospective birth cohort study of all births to Quebec residents, 1991-2000. At the individual level, we examined outcomes comparing births to First Nations and Inuit versus other mother tongue women. At the community level, we compared outcomes among First Nations and Inuit communities versus other communities. RESULTS: First Nations and Inuit births were much less likely to be small-for-gestational-age but much more likely to be large-for-gestational-age compared to other births at the individual or community level, especially for First Nations. At both levels, Inuit births were 1.5 times as likely to be preterm. At the individual level, total fetal and infant mortality rates were 2 times as high for First Nations, and 3 times as high for Inuit. Infant mortality rates were 2 times as high for First Nations, and 4 times as high for Inuit. There were no reductions in these disparities between 1991-1995 and 1996-2000. Modestly smaller disparities in total fetal and infant mortality were observed for First Nations at the community level (risk ratio=1.6), but for Inuit there were similar disparities at both levels. These disparities remained substantial after adjusting for maternal characteristics. CONCLUSION: There were large and persistent disparities in fetal and infant mortality among First Nations and Inuit versus other populations in Quebec based on individual- or community-level assessments, indicating a need to improve socioeconomic conditions as well as perinatal and infant care for Aboriginal peoples.

Community Remoteness, Perinatal Outcomes and Infant Mortality among First Nations in Quebec.

OBJECTIVE: Little is known about community remoteness in relation to birth outcomes among Indigenous populations. We assessed whether community remoteness matters for perinatal outcomes and infant mortality in Quebec First Nations communities. STUDY DESIGN: A retrospective cohort study of all births (n=11,033) to residents of First Nations communities in Quebec 1991-2000, using linked vital statistics data. First Nations communities were grouped by community remoteness into four zones from the least to most remote. RESULTS: Preterm birth rates declined progressively from the least remote (8.0%) to the most remote (5.7%) zones (p=0.002). In contrast, total fetal and infant mortality rose progressively from the least remote (10.4 per 1000) to the most remote (22.7 per 1000) zones (p<0.001). The excess infant mortality in the more remote zones was mainly due to higher rates of postneonatal mortality. Similar patterns were observed after adjusting for maternal age, education, parity and marital status. Substantially elevated risks in most remote communities remained for perinatal death (adjusted OR=2.1), postneonatal death (adjusted OR=2.7), and total fetal and infant death (adjusted OR=2.3). CONCLUSION: Living in more remote First Nations communities was associated with a substantially higher risk of fetal and infant death, especially postneonatal death, despite a lower risk of preterm delivery. There is a need for more effective perinatal and infant care programs in more remote First Nations communities to reduce perinatal and infant mortality.

Urban Living is Not Associated with Better Birth and Infant Outcomes among Inuit and First Nations in Quebec.

OBJECTIVE: There is limited and inconsistent evidence concerning rural versus urban differences in birth and infant outcomes for Indigenous peoples. We assessed birth and infant outcomes among Inuit, First Nations and French mother tongue groups by rural versus urban residence in Quebec, Canada. STUDY DEIGN: A retrospective birth cohort study of 5,184 First Nations, 2,527 Inuit and 652,940 French mother tongue (the majority reference) births in Quebec, 1991-2000. RESULTS: In general, rural living was associated with slightly less favorable birth outcomes for French mother tongue women, but somewhat better outcomes for Indigenous women. For both Inuit and First Nations, rural births were half as likely to be small-for-gestational-age compared to urban births. Among First Nations, the difference in infant mortality rates comparing urban to rural areas was not statistically significant. Compared to infants of French mother tongue women, Inuit and First Nations infants were much less likely to be small-for-gestational-age in rural areas, while such an "advantage" diminished for First Nations and reversed for Inuit in urban areas. The disparities in infant mortality among First Nations versus French mother tongue births were greater in urban than in rural areas. These patterns of results remained after adjusting for maternal characteristics. CONCLUSION: Living in urban areas was not associated with better birth and infant outcomes for Inuit and First Nations in Quebec despite universal health insurance coverage, strongly indicating a need for improved socioeconomic conditions, perinatal and infant care for Indigenous people living in urban areas.