Effects of discontinuation of long-term anticholinergic treatment in elderly schizophrenia patients.

Anticholinergic medication (ACM) is frequently used in psychiatry to treat the side-effects of D2 blocking agents. However, ACM is not without adverse effects and, in the elderly, cognitive and memory impairments have been emphasized. The aim of this study was to evaluate the effects of discontinuation of ACM on cognitive functions in a group of elderly chronic schizophrenia patients. Twenty-seven elderly patients (age 60 years or older), who were diagnosed as suffering from schizophrenia (DSM-IV) and receiving ACM in addition to antipsychotic treatment, were enrolled. Before and after ACM was discontinued, the Alzheimer's Disease Assessment Scale-Cognitive (ADAS-Cog) subscale was administered. Twenty-one patients completed the study. All were receiving Akineton (biperiden), 2-6 mg daily before the study. Significant improvement in the ADAS-Cog total score was demonstrated (P < 0.03), as well as in the ideational praxia and orientation subscales. Improvement was correlated with the previous dose of biperidin. No adverse events or emergent extrapyramidal symptoms were noted. Discontinuation of ACM may be warranted in chronic schizophrenia patients since it may improve cognitive functioning with no adverse effects.

Scopolamine bioavailability in combined oral and transdermal delivery.

Transdermal therapeutic system scopolamine (TTS-S) is effective in preventing motion sickness for 72 h. However, by this route a prophylactic effect is obtained 6 to 8 h postapplication. By the oral route, scopolamine is effective within 0.5 h for a period of 6 h. To achieve safe as well as effective protection against seasickness during the first hours of a voyage until the TTS-S patch takes effect, the pharmacokinetics of scopolamine was investigated after patch application in combination with oral tablets, 0.6 mg, 0. 3 mg, or placebo. Subjects were 25 naval-crew volunteers, randomly divided into three groups: group 1 (n = 9), TTS-S patch + 0.6 mg of scopolamine per os (p.o.); group 2 (n = 8), TTS-S patch + 0.3 mg of scopolamine p.o.; and group 3 (n = 8), TTS-S patch + placebo tablet. Blood samples were collected before treatment and 0.5, 1, 1.5, 2.5, 3.5, 6, 8, and 22 h post-treatment, and were analyzed for scopolamine levels using radioreceptor assay. Significantly higher plasma scopolamine levels were found in group 1 at 0.5, 1, 1.5, and 2.5 h, and in group 2 at 1 and 1.5 h post-treatment, compared with group 3. Thereafter, plasma levels did not differ significantly between the groups. In all subjects of group 1 and seven subjects (88%) of group 2, therapeutic levels (>50 pg/ml) were measured during the first 2.5 h, compared with only two subjects (25%) of group 3 (P < 0.05). Heart rate, blood pressure, visual accommodation, performance test results, and subjective complaints of adverse effects did not differ significantly. The combination of transdermal and oral scopolamine (0.3 or 0.6 mg) provides the required plasma levels to prevent seasickness, starting as early as 0.5 h post-treatment, with no significant adverse effects.

Computerized dynamic posturography and seasickness susceptibility.

OBJECTIVE/HYPOTHESIS: The neural mismatch theory emphasizes the role of conflicting multimodal sensory interactions in producing both motion sickness and the rearrangement process that finally leads to habituation to the adverse motion conditions. If this theory is, indeed, correct, the patterns of the response to the integrated signal from simultaneous multisensory stimulation, characterized by unusual relationships between the senses responsible for spatial orientation, should differ according to motion sickness susceptibility. Computerized dynamic posturography (CDP) provides the opportunity to simultaneously change the interactions between visual, somatosensory, and vestibular inputs, thus giving an indication of the relative importance of these senses in maintaining balance. The objective was to investigate balance strategies in naval crew members with differing susceptibility to sea conditions using CDP. STUDY DESIGN: Cross-sectional, parallel-group design. METHODS: Twenty subjects susceptible to seasickness (SS) and 20 nonsusceptible subjects (NSS), healthy male volunteers aged 18 to 25, were tested using the EquiTest system (NeuroCom, Inc., Clackamas, OR). RESULTS: The SS group exhibited significantly less stability than the NSS group in condition 5 of the sensory organization test (SOT). The ratio of the SOT scores of conditions 5 to 1 (the vestibular organization pattern) was also found to be significantly lower in the SS group. CONCLUSIONS: The results suggest that SS might be more dependent on somatosensory and visual inputs and less on vestibular inputs for maintenance of balance compared with NSS. Higher susceptibility to seasickness might reflect abnormal weighting of sensory modalities during the integration process. This would result in disruption of the integration process required to maintain balance and a sense of orientation in space in conditions producing conflicting sensory inputs.

Inner ear decompression sickness following altitude chamber operation.

Decompression sickness (DCS) is a known hazard of altitude chamber operation. The musculoskeletal, dermal, neurological and pulmonary manifestations of DCS are well recognized, but inner ear injury has not been reported. We present the unusual case of a medical corpsman suffering from vestibular DCS after an altitude chamber exposure to 25,000 ft. The patient had a good clinical response to hyperbaric treatment, but there was laboratory evidence of mild residual vestibular damage with full compensation. This case suggests that aviation medical personnel should be more aware of the possible occurrence of inner ear DCS among subjects exposed to altitude.

Periodic K-alpha sleep EEG activity and periodic limb movements during sleep: comparisons of clinical features and sleep parameters.

The K-alpha sleep electroencephalographic (EEG) phenomenon is characterized by periodic (approximately 20-40 seconds) K-complexes, immediately followed by alpha-EEG activity (7.5-11 Hz) of 0.5- to 5.0-second duration. A group of 14 subjects with the periodic K-alpha anomaly was found to have a similar distribution pattern of interevent intervals as compared with previously published data for sleep-related periodic limb movements during sleep (PLMS). Sleep parameters and somatic symptoms of 30 patients with K-alpha were compared with 30 patients with PLMS. The periodic K-alpha group was predominantly female, younger, exhibiting more slow-wave sleep, gastrointestinal symptoms and muscular complaints and fewer movement arousals on overnight polysomnography. The K-alpha group presented uniformly with complaints of unrefreshing sleep, often associated with fibromyalgia and chronic fatigue syndrome. The PLMS group was predominantly male, showed greater sleep disruption and presented with a variety of sleep-related symptoms.

Diurnal sleep/wake-related immune functions during the menstrual cycle of healthy young women.

Animal and human studies have related the sleeping/waking brain to the immune system. Because women are more susceptible to certain immunological illnesses, and sex steroids regulate immune functions, it was investigated whether the diurnal sleep/wake pattern of aspects of cellular immune functions and interleukin-1 (IL-1) and IL-2-like activities differed during low and high progesterone phases of the menstrual cycle. Eleven healthy women, mean age 24 y, were assessed over 24 h with serial venous blood samples. Peripheral blood monocytes were assayed for mitogen responses, i.e. phytohemagglutin (PHA) and pokeweed (PWM) and natural killer (NK) cell activities. Plasma was assayed for IL-1 and IL-2-like activities, cortisol and progesterone. Data were standardized by Z transformation and analysed by repeated-measures analysis of variance by comparing high (N = 5) vs. low (N = 6) progesterone phases. During the high progesterone phase, delayed slow-wave sleep (SWS) onset time and reduced amount of SWS was accompanied by a delay in the decline of NK cell activity, but rise in PHA activity following sleep onset. With the low progesterone phase, the pattern was similar to men with an early sleep decline in NK cell and late sleep rise in PHA activities. PWM rose during the night and plasma IL-1-like activity peaked during midday and during nocturnal sleep irrespective of the amount of progesterone. Slow-wave sleep and sleep-related NK cell and PHA activities differed over the menstrual cycle, but not PWM response. Increases in plasma IL-1 functions during midday and night are consistent with predisposition to sleepiness during these times.