Medline ® Abstracts for References 17-19
of 'Evaluation of suspected obstructive sleep apnea in children'
The familial aggregation of obstructive sleep apnea.
Redline S, Tishler PV, Tosteson TD, Williamson J, Kump K, Browner I, Ferrette V, Krejci P
Am J Respir Crit Care Med. 1995;151(3 Pt 1):682.
An inherited basis for sleep-disordered breathing (SDB) has been suggested by reports of families with multiple affected members and by a previous study of the familial aggregation of symptoms of SDB. In this study, we quantify and characterize the aggregation of SDB and assess the degree to which familial similarities may be independent of obesity. This was a genetic-epidemiologic study that assessed the distribution of SDB in families identified through a proband with diagnosed sleep apnea and among families in the same community with no relative with known sleep apnea. SDB was assessed with overnight in-home monitoring of airflow, oxygen saturation, chest wall impedance, heart rate, and body movement. Standardized questionnaires were used to assess symptoms, and weight, height, and neck circumference were measured directly. Intergenerational and intragenerational correlation coefficients and pairwise odds ratios (ORs) were calculated with adjustment for proband sampling. In toto, 561 members of 91 families were studied: (1) 47 subjects with laboratory-confirmed SDB (index probands), (2) 44 community control subjects, and (3) the spouses and relatives of 1 and 2. Of all 91 families, 32 (35%) had two or more members with SDB, 30 (33%) had one affected member, and 29 had no affected members. SDB was more prevalent in the relatives of index probands (21%) than among neighborhood control subjects (12%)(p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Medicine, Cleveland Veterans Affairs Medical Center, Ohio 44106.
Genetics of the apnea hypopnea index in Caucasians and African Americans: I. Segregation analysis.
Buxbaum SG, Elston RC, Tishler PV, Redline S
Genet Epidemiol. 2002;22(3):243.
Differences in age of presentation and anatomic risk factors for obstructive sleep apnea (OSA) in Caucasians and African Americans suggest possible racial differences in the genetic underpinnings of the disorder. In this study, we assess transmission patterns in a Caucasian sample consisting of 177 families (N = 1,195) and in an African American sample consisting of 125 families (N = 720) for two variables: 1) apnea hypopnea index (AHI) log transformed and adjusted for age, and 2) AHI log transformed and adjusted for age and body mass index (BMI). We allowed for residual familial correlations and sex-specific means in all models. Analysis of the Caucasian sample showed transmission patterns consistent with that of a major gene that were stronger in the age-adjusted variable than in the age- and BMI-adjusted variable. However, in the African American families, adjusting for BMI in addition to age gave stronger evidence for segregation of a codominant gene with an allele frequency of 0.14, accounting for 35% of the total variance. These results provide support for an underlying genetic basis for OSA that in African Americans is independent of the contribution of BMI.
Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio 44109-1998, USA. firstname.lastname@example.org
Obstructive sleep apnea syndrome in siblings: an 8-year Swedish follow-up study.
Sundquist J, Li X, Friberg D, Hemminki K, Sundquist K
BACKGROUND: Understanding the genetic transmission of obstructive sleep apnea syndrome (OSAS) will help clinicians identify patients at risk and offer opportunities for intervention and treatment at specialist clinics.
OBJECTIVE: To estimate familial risk of hospitalization for OSAS in the adult population of Sweden, and to determine if there are any differences by age and sex.
DESIGN, SETTING, AND PARTICIPANTS: Using the MigMed database at the Karolinska Institute, we divided the population of Sweden into sibling groups based on a shared mother and father and ascertained the presence or absence of a primary hospital diagnosis of OSAS in each individual during the follow-up period, 1997 to 2004. Individuals were categorized as having or not having a sibling with OSAS, based on the presence or absence of the disorder in at least 1 of their siblings. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were estimated for men and women with a sibling with OSAS, compared with men and women in the reference group (SIR = 1).
RESULTS: After accounting for socioeconomic status, age, geographic region, and period of diagnosis, men with at least 1 sibling who had OSAS had a SIR of 3.42 (95% CI, 2.18-5.36); the corresponding SIR in women was 3.25 (95% CI, 1.84-5.65).
CONCLUSIONS: Our results indicate that physicians should consider family history of OSAS when deciding whether to refer a patient for further sleep examinations.
Karolinska Institute, Center for Family and Community Medicine, Huddinge, Sweden.