Psychosocial factors and obesity in 17 high-, middle- and low-income countries: the Prospective Urban Rural Epidemiologic study

Background/Objectives:

Psychosocial stress has been proposed to contribute to obesity, particularly abdominal, or central obesity, through chronic activation of the neuroendocrine systems. However, these putative relationships are complex and dependent on country and cultural context. We investigated the association between psychosocial factors and general and abdominal obesity in the Prospective Urban Rural Epidemiologic study.

Subjects/Methods:

This observational, cross-sectional study enrolled 151 966 individuals aged 35–70 years from 628 urban and rural communities in 17 high-, middle- and low-income countries. Data were collected for 125 290 individuals regarding education, anthropometrics, hypertension/diabetes, tobacco/alcohol use, diet and psychosocial factors (self-perceived stress and depression).

Results:

After standardization for age, sex, country income and urban/rural location, the proportion with obesity (body mass index ⩾30 kg m⁻²) increased from 15.7% in 40 831 individuals with no stress to 20.5% in 7720 individuals with permanent stress, with corresponding proportions for ethnicity- and sex-specific central obesity of 48.6% and 53.5%, respectively (P<0.0001 for both). Associations between stress and hypertension/diabetes tended to be inverse. Estimating the total effect of permanent stress with age, sex, physical activity, education and region as confounders, no relationship between stress and obesity persisted (adjusted prevalence ratio (PR) for obesity 1.04 (95% confidence interval: 0.99–1.10)). There was no relationship between ethnicity- and sex-specific central obesity (adjusted PR 1.00 (0.97–1.02)). Stratification by region yielded inconsistent associations. Depression was weakly but independently linked to obesity (PR 1.08 (1.04–1.12)), and very marginally to abdominal obesity (PR 1.01 (1.00–1.03)).

Conclusions:

Although individuals with permanent stress tended to be slightly more obese, there was no overall independent effect and no evidence that abdominal obesity or its consequences (hypertension, diabetes) increased with higher levels of stress or depression. This study does not support a causal link between psychosocial factors and abdominal obesity.

Influence of dietary and genetic factors on metabolic status in obese and lean postmenopausal women

This preliminary study addressed the possible associations between dietary, genetic and hormonal factors that are involved in the development of menopausal obesity and its metabolic consequences. We performed anthropometrical, hormonal and biochemical measurements and used a nutritional questionnaire on 43 postmenopausal women who were non-HRT-users (14 obese and 29 non-obese subjects, mean age +/- SD of 52.8 +/- 4.6 years, mean body mass 74.6 +/- 4.6 kg). All of the women also had fat mass assessed by DPX-Lunar. From the 24-h dietary recall, the nutrient intake in daily food rations was calculated using a computer program (Nutritionist IV, San Bruno, CA, USA) based on our own database. Restriction fragment length polymorphism of the estrogen-receptor-alpha gene was determined with the PvuII restriction enzyme. Obese women widely under-reported their daily food intake. The analysis of body fat distribution showed that the total body weight and the percentage of total fat mass were significantly increased in the obese group (p = 0.001). We observed significantly higher leptin (20.56 +/- 11.9 vs. 9.02 +/- 2.8 ng/ml) and total cholesterol (but lower cholesterol HDL), triglycerides levels in the obese subjects (261.89 +/- 48.8 vs. 248.23 +/- 55.9; 52.17 +/- 13.6 vs. 60.92 +/- 13.04; 142.82 +/- 61.02 vs. 106.61 +/- 27.7 mg/dl). Except for diastolic blood pressure, clinical variables were not significantly different between subjects with and without the PvuII ERalpha polymorphism. Allele frequencies of the ERalpha polymorphism did not differ from those previously reported (P-0.48, p-0.52) in our study. In this preliminary study we failed to find dietary and genetic factors involved in the pathogenesis of menopausal obesity. However, our results provide support for the notion that the perimenopausal increase in visceral fat is a significant factor involved in the increased cardiovascular risk in postmenopausal women.

Acromegaly due to GHRH-secreting large bronchial carcinoid. Complete recovery following tumor surgery

A case of acromegaly, secondary to GHRH secretion by a large bronchial carcinoid is reported. A 61-year-old woman presented with typical symptoms and signs of acromegaly for at least 10 years. She suffered from recurrent pneumonias, but repeated chest X-ray examinations failed to demonstrate the bronchial tumor. The diagnosis was confirmed by elevated GH, IGF-1 and GHRH secretion. We have shown an enlarged pituitary gland without focal lesions together with a cerebral meningioma on MRI and the presence of a bronchial carcinoid tumor. The latter was confirmed by histology carried out after bronchoscopy and tumor excision. We observed partial suppression of GH secretion following short-term oral bromocriptine administration in this patient. Surgical removal of the carcinoid tumor resulted in a complete clinical, hormonal and radiological cure of acromegaly. This case of acromegaly due to ectopic GHRH secretion by bronchial carcinoid differs from others described in the literature by an atypical large tumor size, the suppression of elevated GH secretion by oral bromocriptine and a concomitant meningioma.