Mechanisms of body weight gain in patients with Parkinson's disease after subthalamic stimulation.

Chronic bilateral subthalamic stimulation leads to a spectacular clinical improvement in patients with motor complications. However, the post-operative body weight gain involved may limit the benefits of surgery and induce critical metabolic disorders. Twenty-four Parkinsonians (61.1 +/- 1.4 years) were examined 1 month before (M - 1) and 3 months after (M + 3) surgery. Body composition and energy expenditure (EE) were measured (1) over 36 h in calorimetric chambers (CC) with rigorous control of food intakes and activities [sleep metabolic rate, resting activities, meals, 3 or 4 sessions of 20 min on a training bicycle at 13 km/h and daily EE] and (2) in resting conditions (basal metabolic rate) during an acute L-dopa challenge (M - 1) or according to acute 'off' and 'on' stimulation (M + 3). Before surgery, EE was compared between the Parkinsonian patients and healthy subjects matched for height and body composition (metabolic rate during sleep, daily EE) or matched to predicted values (basal metabolic rate). Before surgery, in Parkinsonian men but not women, (1) daily EE was higher while sleep metabolic rate was lower compared to healthy matched men (+9.2 +/- 3.9 and -8.2 +/- 2.3%, respectively, P < 0.05) and (2) basal metabolic rate (L-dopa 'on') was higher than predicted basal metabolic rate (+11.5 +/- 4.0%, P < 0.05) but was further increased without L-dopa (+8.4 +/- 3.2% vs L-dopa 'on', P < 0.05). EE during daily activities was higher during 'off' periods compared to 'on' periods for both men (+19.3 +/- 3.3%, P < 0.0001) and women (+16.1 +/- 4.7%, P < 0.01). After surgery, there was a 3.4 +/- 0.6 kg (P < 0.0001) body weight increase together with fat mass (P < 0.0001) and fat-free mass (P < 0.05) in Parkinsonian men and a 2.6 +/- 0.8 kg (P < 0.05) body weight increase together with fat mass (P < 0.05) in Parkinsonian women. Sleep metabolic rate increased in men (+7.5 +/- 2.0%, P < 0.01) to reach control values but remained unchanged in women. Daily EE decreased significantly in both men and women (-7.3 +/- 2.2% and -13.1 +/- 1.7%, respectively, P < 0.01) but there was no correlation between daily EE changes and body weight gain. Parkinson's disease is associated with profound alterations in the central control of energy metabolism. Normalization of energy metabolism after DBS-STN implantation may favour body weight gain, of which quality was gender specific. As men gained primarily fat-free mass, a reasonable weight gain may be tolerated, in contrast with women who gained only fat. Other factors such as changes in free-living physical activity may help to limit body weight gain in some patients.

Zinc intake and status in middle-aged and older European subjects: the ZENITH study.

OBJECTIVE: Inadequate intakes of micronutrients in elderly negatively affect the nutritional status. Zinc is an essential micronutrient in the elderly, especially in relation to its impact on immune function, bone mass, cognitive function and oxidative stress. However, data are lacking on zinc intake and status during normal ageing. In this study, we evaluate the intake and status of zinc in late middle-aged and older free-living subjects. DESIGN: Dietary zinc intake and zinc status in 188 middle-aged subjects from Clermont-Ferrand (Fr) and Coleraine (UK), and in 199 older subjects from Grenoble (Fr) and Roma (It) were assessed at the entry in the ZENITH study. RESULTS: In relation to the zinc RDA for people older than 55 y, zinc intakes in most of the middle-aged and older subjects (more than 96%) in the present study were adequate. Older people had significantly lower (P < 0.01) energy intakes as compared to middle-aged. Zinc intake expressed per MJ was also significantly (P < 0.01) higher in older people compared to middle-aged. Erythrocyte and urinary zinc concentrations were significantly (P < 0.001) higher in middle-aged subjects compared to older ones. The prevalence of biological Zn deficiency in free-living ageing European people was low (<5%). CONCLUSION: The results of the present study showed a relatively low prevalence of zinc deficiencies in healthy free-living late middle-age and older subjects. These results should be useful for health professionals to have reference data on zinc intake and status for a healthy ageing.

Impact of micronutrient dietary intake and status on intestinal zinc absorption in late middle-aged men: the ZENITH study.

BACKGROUND: Adjustments in intestinal absorption and losses of zinc (Zn) are thought to maintain Zn homeostasis when dietary intake levels are altered. Zn status may also influence efficiency of intestinal Zn absorption. OBJECTIVES: To determine the impact of dietary intake and status of some micronutrients on Zn absorption in late middle-aged men. DESIGN AND PARTICIPANTS: Dietary intake and status of Zn, Cu, Fe, vitamin A, C and fibre, and absorption of Zn were measured in 48 men, aged 58-68 y, confined to a metabolic unit and consuming a typical French diet. Dietary intake was estimated using 4-day food-intake records (including the weekend) and the GENI program. To assess Zn status, serum, erythrocyte, urine Zn levels and serum alkaline phosphatase activity were determined. Zn absorption was determined using the isotope double-labelling method. Zn stable isotopic ratios were measured in plasma samples collected before and 48 h after isotope administration using ICP/MS. RESULTS: Zn intake within the group of men varied from 5.7 to 20.5 mg/day and averaged 12.9 mg/day. Serum Zn level varied from 10 to 18 micromol/l and averaged 12.9 micromol/l. Zn absorption varied from 12 to 46% and averaged 29.7%. Zn absorption was not significantly (P > 0.05) correlated with Zn intake or with any of the Zn status parameters. Zn absorption was only slightly negatively correlated with serum and erythrocyte Zn levels and with serum Fe and ferritin levels in this study. CONCLUSION: Zn dietary intake and Zn absorption were satisfactory and led to an adequate Zn status in this population.