Nicotine deprivation and pilot performance during simulated flight.

OBJECTIVES: Most airlines enforce no-smoking policies, potentially causing flight performance decrements in pilots who are smokers. We tested the hypotheses that nicotine withdrawal affects aircraft pilot performance within 12 h of smoking cessation and that chewing nicotine gum leads to significant relief of these withdrawal effects. METHODS: There were 29 pilots, regular smokers, who were tested in a Frasca 141 flight simulator on two 13-h test days, each including three 75-min flights (0 hr, 6 hr, 12 hr) in a randomized, controlled trial. On the first day (baseline), all pilots smoked one cigarette per hour. On the second day, pilots were randomly assigned to one of four groups: (1) nicotine cigarettes; (2) nicotine gum; (3) placebo gum; (4) no cigarettes/no gum. Flight Summary Scores (FSS) were compared between groups with repeated measures ANOVAs. RESULTS: No statistically significant differences in overall simulator flight performance were revealed between pilots who smoked cigarettes and pilots who were not allowed to smoke cigarettes or chew nicotine gum, but there was a trend for pilots who were not allowed to smoke to perform worse. However, pilots who chewed placebo gum performed significantly worse during the 6-h (FSS = -0.03) as well as during the 12-h flight (FSS = -0.08) than pilots who chewed nicotine gum (FSS = 0.15 / 0.30, respectively). CONCLUSIONS: Results suggest that nicotine withdrawal effects can impair aircraft pilot performance within 12 h of smoking cessation and that during smoking abstinence chewing one stick of 4-mg nicotine gum per hour may lead to significantly better overall flight performance compared to chewing placebo gum.

Acetylcholinesterase inhibitor in combination with cognitive training in older adults.

To determine if donepezil, an acetylcholinesterase (AChE) inhibitor, improved the assimilation of cognitive training by older adults with memory complaints, we gave 168 nondemented, community-dwelling volunteers with memory complaints either 5 mg of donepezil (Aricept) or placebo daily for 6 weeks in a randomized, double-blind, placebo-controlled trial. The dosage rose to 10 mg daily for another 6 weeks before a 2-week course of cognitive training and was maintained for the remainder of a year. Cognitive training improved performance; donepezil was well tolerated. However, there were no significant benefits of donepezil compared with placebo. An additional dose-ranging study with a starting dose of 5 mg a day suggests that the high dose was not the reason. Physiological tolerance may occur with chronic donepezil treatment and may increase AChE levels; this may be why short-term studies have shown the benefit of AChE inhibitor use in nondemented participants whereas chronic use has failed to enhance cognition.

Hormone replacement therapy and longitudinal cognitive performance in postmenopausal women.

OBJECTIVE: The authors examined the impact of hormone replacement therapy (HRT) on longitudinal cognitive performance (controlling for mood state) in 69 community-dwelling, postmenopausal women. METHODS: The authors conducted a 5-year follow-up of cognitive performance in 37 postmenopausal HRT users and 32 non-users. The groups did not differ with respect to age, years of education, or inter-test interval. RESULTS: No main effect of HRT was observed on any of the cognitive measures, and depressive symptomatology did not affect the relationship between HRT and cognition. CONCLUSION: Overall, our findings do not suggest that HRT affects longitudinal cognitive performance in postmenopausal, community-dwelling older women.

Underreporting of behavioral problems in older hospitalized patients.

This descriptive study examined reports of behavioral problems among older patients hospitalized in acute care medical settings. Greater numbers of behavioral problems were reported by nursing staff on the Neuropsychiatric Inventory-Questionnaire than were documented in medical charts over the same time period. Such underreporting may have clinical and administrative implications.

Cognitive ability, expertise, and age differences in following air-traffic control instructions.

Differences in cognitive ability and domain-specific expertise may help explain age differences in pilot performance. Pilots heard air-traffic controller messages and then executed them while "flying" in a simulator. Messages varied in length and speech rate. Age was associated with lower accuracy, but the expected Age x Message Difficulty interactions were not obtained. Expertise, as indexed by pilot ratings, was associated with higher accuracy; yet expertise did not reduce age differences in accuracy. The effect of age on communication task accuracy was largely explainable as an age-associated decrease in working memory span, which in turn was explainable as decreases in both speed and interference control. Results are discussed within frameworks of deliberate practice and cognitive mediation of age differences.

Age and disease severity predict choice of atypical neuroleptic: a signal detection approach to physicians' prescribing decisions.

OBJECTIVE: We used a novel application of a signal detection technique, receiver operator characteristics (ROC), to describe factors entering a physician's decision to switch a patient from a typical high potency neuroleptic to a particular atypical, olanzapine (OLA) or risperidone (RIS). METHODS: ROC analyses were performed on pharmacy records of 476 VA patients who had been treated on a high potency neuroleptic then changed to either OLA or RIS. RESULTS: Overall 68% patients switched to OLA and 32% to RIS. The best predictor of neuroleptic choice was age at switch, with 78% of patients aged less than 55 years receiving OLA and 51% of those aged greater than or equal to 55 years receiving OLA (chi(2)=38.2, P<0.001). Further analysis of the former group indicated that adding the predictor of one or more inpatient days to age increased the likelihood of an OLA switch from 78% to 85% (chi(2)=7.3, P<0.01) while further analysis of the latter group indicated that adding the predictor of less than 10 inpatients days to age decreased the likelihood of an OLA switch from 51% to 45% (chi(2)=7.0, P<0.01). CONCLUSIONS: ROC analyses have the advantage over other analyses, such as regression techniques, insofar as their "cut-points" are readily interpretable, their sequential use forms an intuitive "decision tree" and allows the potential identification of clinically relevant "subgroups". The software used in this analysis is in the public domain (http://mirecc.stanford.edu).

Psychoactive drugs and pilot performance: a comparison of nicotine, donepezil, and alcohol effects.

The cholinergic system plays a major role in cognitive abilities that are essential to piloting an aircraft: attention, learning, and memory. In previous studies, drugs that enhance the cholinergic system through different pharmacologic mechanisms have shown beneficial effects on cognition; but dissimilar cognitive measures were used and samples were not comparable. A comparison within the same cognitive tasks, within comparable samples appears desirable. Toward this aim, we compared effect sizes (ES) of performance-enhancing doses of nicotine (a nicotinic receptor agonist) and donepezil (an acetylcholinesterase inhibitor) as found in our prior work on pilot performance. We also compared cholinergic ES to those of performance-impairing doses of alcohol. In three randomized, placebo-controlled trials, we assessed the flight performance of aircraft pilots in a Frasca 141 simulator, testing I: the acute effects of nicotine gum 2 mg; II: the effects of administration of 5 mg donepezil/day for 30 days; and III: the acute and 8 h-carryover effects of alcohol after a target peak BAC of 0.10%. We calculated the ES of nicotine, donepezil, and alcohol on a flight summary score and on four flight component scores. Compared to placebo, nicotine and donepezil significantly improved, while alcohol significantly impaired overall flight performance: ES (nicotine)=0.80; ES (donepezil)=1.02; ES (alcohol acute)=-3.66; ES (alcohol 8 h)=-0.82. Both cholinergic drugs showed the largest effects on flight tasks requiring sustained visual attention. Although the two tested cholinergic drugs have different pharmacologic mechanisms, their effects on flight performance were similar in kind and size. The beneficial effects of the cholinergic drugs on overall flight performance were large and the absolute (ie nondirectional) sizes were about one-fourth of the absolute ES of acute alcohol intoxication and roughly the same as the absolute 8 h-carryover ES of alcohol.

Cognitive status and behavioral problems in older hospitalized patients.

OBJECTIVES: (a) To determine the quantity and quality of behavioral problems in older hospitalized patients on acute care units; (b) to determine the burden of these behaviors on staff; and (c) to identify predictors of behavioral problems. METHODS: Upon admission, patients performed the Mini-Mental State Exam (MMSE), the Geriatric Depression Scale (GDS), and information was obtained on age, ethnicity, level of education, living arrangement, and psychiatric history. Two days post-admission, a clinical staff member caring for each patient, performed the Neuropsychiatric Inventory-Questionnaire (NPI-Q) to assess patients' behavioral problems and staff distress. PARTICIPANTS AND SETTING : Forty-two patients, over 60 years of age, admitted to medical and surgical units of the Veterans Affairs Hospitals in Palo Alto and San Francisco, participated. RESULTS: Twenty-three of 42 (55%) patients exhibited behavioral problems. Anxiety, depression, irritability, and agitation/aggression were the most frequently observed behaviors. The severity of the behavioral problems was significantly correlated with staff distress. Lower performance on the MMSE at admission was significantly associated with higher NPI-Q ratings. Specifically, of those cases with scores less than or equal to 27 on the MMSE, 66% had behavioral problems during hospitalization, compared to only 31% of those with scores greater than 27. CONCLUSION: Behavioral problems in older hospitalized patients appear to occur frequently, are a significant source of distress to staff, and can result in the need for psychiatric consultation. Assessment of the mental status of older adults at admission to hospital may be valuable in identifying individuals at increased risk for behavioral problems during hospitalization.