Heart defects and other malformations in the Inuit in Canada: a baseline study.

OBJECTIVES: Birth defects occur in all ethnic groups, remaining an important world-wide cause of perinatal and infant morbidity. This contributes greatly to an excess of health care dollars allocated to the care and repair of those affected. This is especially true when those affected live in remote geographical locations. STUDY DESIGN: A chart review of 2567 live births of children of Inuit parents residing in Arctic Quebec (Nunavik) and on Baffin Island (Nunavut) between 1989 and 1994 (five years) was carried out compared to rates of anomalies of the Alberta Congenital Anomalies Surveillance System (ACASS). RESULTS: Birth defects were higher in the Inuit sample in nearly every major ICD-9 category with the exception of neural tube defects, eye anomalies and chromosome abnormalities. (Total: 99.7/1000 Vs 51.5/1000; OR 1.93 95% CI 1.7-2.3). Congenital heart defects were significantly increased 22.9/1000 Vs 5.6/1000, with an OR of 4.18 (95% CI 3.2-5.4) in the ICD-9 category 745. In particular, ventricular septal defects (VSDs) and atrial septal defects (ASDs) (OR 4.9 CI 3.5-6.9 and 4.6 CI 2.9-7.2) were frequent. CONCLUSIONS: A high rate of heart defects was an important contributor to the nearly two times rate of total birth defects in the Inuit compared to the ACASS. Further study should be carried out to determine the contributing factors. Genetic predisposition to specific heart defects, and a diet low in folate and vitamin A are considerations. The use of alcohol may exacerbate vitamin status in pregnancy. Optimizing vitamin status in the periconceptional period may reduce the rate of birth defects.

Discordant measures of androgen-binding kinetics in two mutant androgen receptors causing mild or partial androgen insensitivity, respectively.

We have characterized two different mutations of the human androgen receptor (hAR) found in two unrelated subjects with androgen insensitivity syndrome (AIS): in one, the external genitalia were ambiguous (partial, PAIS); in the other, they were male, but small (mild, MAIS). Single base substitutions have been found in both individuals: E772A in the PAIS subject, and R871G in the MAIS patient. In COS-1 cells transfected with the E772A and R871G hARs, the apparent equilibrium dissociation constants (Kd) for mibolerone (MB) and methyltrienolone are normal. Nonetheless, the mutant hAR from the PAIS subject (E772A) has elevated nonequilibrium dissociation rate constants (k(diss)) for both androgens. In contrast, the MAIS subject's hAR (R871G) has k(diss) values that are apparently normal for MB and methyltrienolone; in addition, the R871G hAR's ability to bind MB resists thermal stress better than the hAR from the PAIS subject. The E772A and R871G hARs, therefore, confer the same pattern of discordant androgen-binding parameters in transfected COS-1 cells as observed previously in the subjects' genital skin fibroblasts. This proves their pathogenicity and correlates with the relative severity of the clinical phenotype. In COS-1 cells transfected with an androgen-responsive reporter gene, trans-activation was 50% of normal in cells containing either mutant hAR. However, mutant hAR-MB binding is unstable during prolonged incubation with MB, whereas normal hAR-MB binding increases. Thus, normal equilibrium dissociation constants alone, as determined by Scatchard analysis, may not be indicative of normal hAR function. An increased k(diss) despite a normal Kd for a given androgen suggests that it not only has increased egress from a mutant ligand-binding pocket, but also increased access to it. This hypothesis has certain implications in terms of the three-dimensional model of the ligand-binding domain of the nuclear receptor superfamily.

Indications for transfer for childbirth in Inuit women at the Innuulisivik Maternity.

The Innuulisivik Maternity is a northern-based service in Povungnituk, Quebec, which serves the Inuit women of the Hudson Coast. Although most women stay in the North for childbirth, others are transferred south. This paper will describe the experience of the Innuulisivik Maternity, which uses committee-based risk assessment for transfer decisions. Data for the three-year period 1989-1991 were examined. Descriptive statistics were used to compare the observed differences in the distribution of several variables according to birthplace. Data were available for 411 women. Three hundred fifty (85.2%) of the births occurred at Innuulisivik: 44 (10.7%) women were transferred and 17 (4.1%) were nursing station births. In 80% of transfers, clinical conditions were identified which in themselves usually require transfer. Premature labor was prevalent in the transfer group. The data demonstrate that risk scoring by consensus is a viable option for northern birthing units. Finally, logistical and cultural factors should be included for meaningful risk assessment in the North.

The health of Indian and inuit children in Canada in the 1980s and 1990s.

The last 20 years have seen important improvements in the health status of Native Canadian children. Discrepancies in health status remain between Native and other Canadians. Further improvement is less likely to result from adding more medical services than from broader social change. The economic and cultural base of Native communities needs strengthening. Indian and Inuit people need the opportunities and resources to assume responsibility for their own health and social services in the context of a broader transfer of control. Such a transfer will mark the end of a struggle for Native peoples and the beginning of a new challenge for Native people and for those who work on their behalf.

Adolescents with chronic disease. Are they receiving comprehensive health care?

A survey of adolescents with a chronic disease attending six specialty clinics was conducted to determine the sources of their primary health care and to estimate the extent of unmet health needs. Sixty-one patients completed a self-administered questionnaire. Forty percent had no source of primary care other than the subspecialty clinic treating their chronic condition. Seventy-eight percent regarded the subspecialist as their "personal" physician, although only 27% actually spoke to this physician about their general health needs. For 44% general health needs were not being met. These findings suggest that these adolescents expect the subspecialty clinic to provide primary care; yet they receive, at best, fragmented health care. This situation could be improved by a decision on the part of the subspecialty to restrict its role to providing only specific specialty care or to coordinate overall care.

Applications of health care research to child health services: a problematic relationship.

The direct impact of community health surveys on clinical practice is, essentially, unknown. The importance of behavioral problems as an unmet child health need was demonstrated by studies in the Isle of Wight (UK) and Rochester, New York (USA). Follow-up reports suggest persistently inadequate recognition of such problems by samples of practitioners in these two places. Several American centers have evaluated the training and use of pediatric nurse practitioners in response to a perceived shortage of personnel and maldistribution of primary care for children. A comparison of surveys of American pediatric practices before and after these reports reveals persistent shortcomings in the degree of delegation of tasks to auxiliary personnel. General strategies to improve the responses of primary care practitioners to survey research findings are discussed, with particular emphasis on the role of the individual investigator.