beta2-adrenergic receptor polymorphisms and salbutamol-stimulated energy expenditure.

The beta-adrenergic system is involved in the control of energy metabolism and expenditure. The beta2-adrenergic receptor (beta2-AR) gene shows polymorphisms that have been associated with obesity in several studies. In vitro and in vivo studies suggest differences in beta2-AR-mediated function between these polymorphisms. The aim of this study was to investigate the influence of genetic variation in codon 16 of the beta2-AR gene on energy metabolism in humans. Thirty-four subjects were recruited [Gly16Gly (n = 13), Gly16Arg (n = 16), or Arg16Arg (n = 5)]. The beta2-AR was stimulated with two doses of salbutamol (50 and 100 ng/kg fat-free mass per minute) after blockade of the beta1-adrenergic receptors with atenolol. Energy expenditure and plasma substrate and hormone concentrations were measured. The increase in energy expenditure (DeltaEE) was significantly different among groups in which the Arg16Arg group showed the lowest increase (P < 0.05 vs. Gly carriers). In a multiple regression model, variations in the increase in nonesterified fatty acid concentration during salbutamol infusion (partial r = 0.51) and the polymorphism contributed significantly to the variation in DeltaEE. Thirty-five percent of the variation in DeltaEE was explained by these two factors. We conclude that subjects with the Arg16Arg polymorphism of the beta2-AR gene have a reduced thermogenic response to beta2-adrenergic stimulation. Although this relatively small study needs confirmation, the findings support a role for this polymorphism in the development and maintenance of overweight and obesity.

Employment grade differences in cause specific mortality. A 25 year follow up of civil servants from the first Whitehall study.

STUDY OBJECTIVE: To test the hypothesis that the association between socioeconomic status and mortality rates cuts across the major causes of death for middle aged and elderly men. DESIGN: 25 year follow up of mortality in relation to employment grade. SETTING: The first Whitehall study. PARTICIPANTS: 18,001 male civil servants aged 40-69 years who attended the initial screening between 1967 and 1970 and were followed up for at least 25 years. MAIN OUTCOME MEASURE: Specific causes of death. RESULTS: After more than 25 years of follow up of civil servants, aged 40-69 years at entry to the study, employment grade differences still exist in total mortality and for nearly all specific causes of death. Main risk factors (cholesterol, smoking, systolic blood pressure, glucose intolerance and diabetes) could only explain one third of this gradient. Comparing the older retired group with the younger pre-retirement group, the differentials in mortality remained but were less pronounced. The largest decline was seen for chronic bronchitis, gastrointestinal diseases and genitourinary diseases. CONCLUSIONS: Differentials in mortality persist at older ages for almost all causes of death.

Socioeconomic status and aortic atherosclerosis in Dutch elderly people: the Rotterdam Study.

An inverse association has been reported between socioeconomic status (SES) and cardiovascular morbidity and mortality. Studies on subclinical manifestations of atherosclerotic disease are limited and have not been carried out among elderly persons. The authors investigated the relation between SES and aortic atherosclerosis among elderly people. As part of the Rotterdam Study, data on SES and atherosclerosis were collected for 4,451 persons aged 55-94 years. Atherosclerosis was estimated by radiographic assessment of calcified deposits in the abdominal aorta. Aortic atherosclerosis was more common among women in the lower educational and occupational strata. The lowest educational group and the lowest occupational group had increased risks of aortic atherosclerosis compared with the highest groups (odds ratios were 1.3 (95% confidence interval (CI) 1.0-1.6) and 1.3 (95% CI 1.0-1.8), respectively). The odds ratios for severe atherosclerosis among women in the lowest socioeconomic stratum compared with those in the highest stratum were 1.6 (95% CI 1.0-2.7) for education, 2.8 (95% CI 1.1-7.5) for occupation, and 1.7 (95% CI 0.9-3.3) for income. After exclusion of persons with a history of cardiovascular disease, the same trends still emerged. No relations were observed among men. These findings show that SES is related to aortic atherosclerosis in women. This suggests that SES affects the incidence of cardiovascular disease before its clinical manifestation.

Socioeconomic differences in stroke among Dutch elderly women: the Rotterdam Study.

BACKGROUND AND PURPOSE: We sought to assess the association between socioeconomic status and the risk of stroke among elderly women. Methods--The association between socioeconomic status and stroke emerged in cross-sectional and longitudinal data on 4274 female participants of the Rotterdam Study, a prospective, population-based, follow-up study in the Netherlands among older subjects. RESULTS: A history of stroke was more common among women in lower socioeconomic strata. The same trend was observed for the relationship between the lowest socioeconomic groups and the incidence of stroke. Risk factors for stroke were not related to socioeconomic status in a consistent manner. Smoking, history of cardiovascular diseases, and overweight were more common in lower socioeconomic groups. However, socioeconomic differences in hypertension, antihypertensive drug use, prevalence of atrial fibrillation, and prevalence of left ventricular hypertrophy were not observed. The complex of established risk factors could only partly explain the association between socioeconomic status and stroke. CONCLUSIONS: There is a strong association among elderly women between socioeconomic status and stroke. The association could only partly be explained by known risk factors. Our findings indicate that not only the actual risk profile but also risk factors earlier in life may be of importance.