A complete enumeration of the elderly in ethnic minority groups is best achieved by using several different methods. Diagnosis of dementia may be misleading among those who do not speak the dominant language.
Neuropeptide Y (NPY) is a potent central appetite stimulant whose concentrations rise markedly in hypothalamic appetite-regulating regions in food-deprived rats. To determine whether increased energy expenditure also affects hypothalamic NPY, we studied the effects of intense physical exercise in rats (n = 10) running voluntarily on a large-diameter exercise wheel. Running was initiated by restricting food intake but stabilized at an average of 8 km/day when food intake was matched to that in 11 nonexercised, freely fed controls [23.9 +/- 1.9 (SE) g/day vs. 24.7 +/- 1.3 g/day; P > 0.5]. Running expended approximately 40% of daily energy intake, and weight gain was significantly inhibited. A separate group (n = 10) of nonexercised rats was food restricted (approximately 15 g/day) to match the weights of the exercised rats. The rats were killed after 40 days, when both experimental groups weighed 30% less than controls (P < 0.01). Hypothalamic NPY concentrations showed significant (P < 0.01) increases of 30-70% in specific regions (arcuate and dorsomedial nuclei and medial preoptic and lateral hypothalamic areas) in both the running and food-restricted groups, compared with controls. There were no significant differences between the two experimental groups in NPY concentrations in any hypothalamic region. These findings suggest that negative energy balance, whether caused by reduced energy intake or increased expenditure, increases hypothalamic NPYergic activity. As NPY acts on the hypothalamus to increase body weight, these data support the postulated homeostatic role of NPY in maintaining nutritional state.
The opportunity to assess prevalence, incidence, and outcome of schizophrenia and delusional disorder was provided by an age- and sex-stratified random sample of 5,222 persons age 65 years and over. This sample was chosen from general practitioner lists, and interviewed by psychiatric nurses trained to use the Geriatric Mental State (GMS)-AGECAT computerized diagnostic system. GMS-AGECAT ensured the reliability of the selection of cases between the two waves of the study. A subsample was interviewed by a research psychiatrist. The sample was followed up 2 years later using the same method by interviewers blind to the initial findings. The protocols of all nominated cases and subcases of schizophrenia/paranoid disorder diagnosed by AGECAT were reviewed by a clinician and DSM-III-R diagnoses were made. Refusal rate was 13 percent for initial interviews (wave 1) and 15 percent for reinterview 2 years later (wave 2). The prevalence of DSM-III-R schizophrenia was 0.12 percent (95% confidence interval [CI] 0.04-0.25) and delusional disorder 0.04 percent (95% CI 0.00-0.14). The minimum incidence of schizophrenia for new cases was 3.0 (95% CI 0.00 to 110.70); for new and relapsed cases, 45.0 (95% CI 3.54-186.20); and for delusional disorder, 15.6 (95% CI 0.02-135.10) per 100,000 per year. Two of the five cases with schizophrenia were known to have been first diagnosed before age 65. After 2 years, none of the cases of schizophrenia had recovered fully, but none was deluded at followup. Two had developed dementia. The outcome was bad because they remained cases of some type of psychiatric illness but good because of the improvement in their schizophrenia/delusion disorder symptoms.
Regional hypothalamic concentrations of neuropeptide Y (NPY) and corticotropin-releasing factor (CRF), respectively a stimulant and an inhibitor of feeding behavior, were investigated in hypothalamic nuclei in rats carrying the Yoshida sarcoma. Tumor-bearing rats (n = 10), non-tumor-bearing controls (n = 10), and food-restricted rats (n = 10), which did not carry tumors but were pair-fed to match the reduced food intake of the tumor-bearing group, were studied after 10 days. NPY concentrations in the arcuate nucleus (ARC, the main site of NPY synthesis) were significantly increased above controls (P < 0.01) in both tumor-bearing and food-restricted groups. However, NPY concentrations in the paraventricular nucleus (PVN, an NPY-sensitive site of NPY release) showed opposing changes, with a 25% decrease (P = 0.052) in the tumor-bearing but a 48% increase (P < 0.01) in the food-restricted group. CRF concentrations in both the PVN and the ARC were significantly reduced (P < 0.01) in the food-restricted group, but remained close to control values in the tumor-bearing group (P not significant). Changes in hypothalamic appetite-regulating neuropeptides in cancer anorexia, which may result from the action of cytokines produced by a host defense response or the tumor itself, may account for reduced feeding. Such changes may include impaired activity of NPY or failure of CRF activity to be suppressed after underfeeding and weight loss.
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