Birthplace in area with high coronary heart disease mortality predicts the severity of coronary atherosclerosis among middle-aged Finnish men who had migrated to capital area: the Helsinki sudden death study.

BACKGROUND: Reasons why eastern-born male Finns have higher coronary heart disease (CHD) mortality than do western-born men are still unsettled. Recently, eastern birthplace was found to be an independent predictor of pre-hospital sudden cardiac death (SCD) in the new low-mortality area of residence. AIM: To investigate the association of birthplace with high CHD mortality attributes to more severe coronary atherosclerosis among men migrated to the low-mortality capital area. METHOD: Coronary atherosclerosis was measured in 373 western-born and 314 eastern-born out-of-hospital male deaths aged 33-70 years in Helsinki (The Helsinki Sudden Death Study), covering 24.6% of male deaths within this age-group. CHD risk factors were obtained from an interview of a next of kin. RESULTS: In multivariate analysis there was a strong birthplace-by-age interaction with atherosclerosis (P = 0.0005). Eastern-born men <54 years had larger areas of fatty streaks (P = 0.0195), fibrotic plaque (P = 0.0133), calcification (P = 0.0009), total plaque area (P = 0.0011), and greater stenosis (P = 0.0004) in the left coronary compared to western-born men, independent of CHD risk factors. Amongst older men (>or=54 years) such an association no longer appeared. CONCLUSION: Higher CHD mortality among eastern-born men may be due to more severe coronary atherosclerosis independently of CHD risk factors, reflecting Finns' two-phase settlement history.

Birthplace predicts risk for prehospital sudden cardiac death in middle-aged men who migrated to metropolitan area: The Helsinki Sudden Death Study.

BACKGROUND: Eastern-born male Finns, irrespective of their place of residence, have high mortality from coronary heart disease (CHD), and half of such deaths are sudden. AIM: To study whether eastern birthplace alone or combined with life-style factors predicts risk for prehospital sudden cardiac death (SCD) in the new (west) low-mortality area of residence. METHOD: Prospective case-control autopsy study of all (700) out-of-hospital deaths of men aged 35-69 years in metropolitan Helsinki during 1981-82 and 1991-92. Data on CHD risk factors were obtained for 405, of whom 149 died of SCD (cases) and 256 of other causes (controls). RESULTS: A birthplace-by-age interaction with SCD (P=0.024) and with myocardial infarction (P=0.005) appeared. Men < or =54 years born in the east were more often victims of SCD (odds ratio 2.99, 95% confidence interval 1.38-6.49, P=0.006) than were men born in the west, independently of CHD risk factors. SCD was predicted also by alcohol consumption, age, smoking, and hypertension. Amongst older (>54 years) men no association with birthplace was any longer evident, but alcohol and socio-economic status predicted SCD. CONCLUSIONS: Birthplace-based risk for SCD suggests the contribution of early life environment or genetic east-west differences, reflecting Finns' two-phase settlement history.

Modelling individual space-time exposure opportunities: a novel approach to unravelling the genetic or environment disease causation debate.

The aetiology of Amyotrophic Lateral Sclerosis (ALS) is uncertain. While around 10% is assumed to be inherited, the relative influence of genetic versus physical or social environmental factors (or some combination of the two) has yet to be determined. A previous study identified significant clustering of ALS at the time of birth in south-east Finland and this could support either a genetic or an environmental hypothesis. We know that south-east Finland is an environmentally degraded area, but the population in this region may also be genetically susceptible to this condition. We therefore extend this research by comparing the lifetime residential histories of 1000 ALS cases and 1000 controls matched by birth date, sex and municipality of birth. By focusing on those who originated in the south-east, and comparing the subsequent residential mobility of these two groups, we test whether remaining in south-east Finland is more common among cases than controls and, hence, whether there may be an environmental or genetic influence on ALS associated with that region. Our results indeed suggest that the cases were more likely to remain in south-east Finland after birth, compared to the geographically matched controls. This suggests that moving away is protective, and points towards a risk factor after birth being implicated in the aetiology of the disease.

Postural cephalometric analysis and nasal resistance in sleep-disordered breathing.

OBJECTIVES: The study was designed to compare upright and supine cephalometric measurements in snorers and to evaluate the effects of mandibular position and nasal resistance on pharyngeal dimensions. Anthropometric, rhinomanometric, and cephalometric measurements were used to investigate predictors of apnea-hypopnea index. STUDY DESIGN: Prospective, cross-sectional. METHODS: Forty consecutive habitually snoring men waiting for nasal surgery (mean age, 44 y; mean body mass index, 28 kg/m2) underwent an overnight polysomnographic, anterior rhinomanometric, and cephalometric analysis in upright and supine positions. RESULTS: Nasal resistance correlated positively with minimal pharyngeal airspace at the level of tongue. The opening of jaws after voluntary relaxation of the mandibular position on lying down correlated with decrease in pharyngeal airway measurements at both velopharyngeal and tongue-base levels. In stepwise multiple regression analysis the overall patient model explained 68% of the variation in apnea-hypopnea index with body mass index as the largest predictor. In the nonobese patients, the model explained 86% of variation in apnea-hypopnea index with change in anteroposterior position of the lower jaw in upright and supine measurements and combined nasal resistance after mucosal decongestion as independent determinants. In selected skeletal subtypes the models predicted 83%, 79%, 61%, and 90% of the variation in apnea-hypopnea index. CONCLUSIONS: In the nonobese patients nasal resistance and change in mandibular position on lying down were found to be independent contributing factors to the apnea-hypopnea index. Further research on supine cephalometry and relaxed mandibular position may improve prediction of sleep-disordered breathing in snorers.