Real-world problem solving and quality of life in older people.

OBJECTIVES: This study examined relationships between quality of life (QoL) in older people and cognitive functioning in both abstract and real-world problem solving. DESIGN: Contributions of levels of mental, physical and social activities, self-rated and objective health status, self-rated cognitive functioning, socio-economic status, gender, real-world and abstract problem solving were examined in a regression study of factors related to QoL in older people. METHOD: Participants (N=145) were 70-91 years of age. The current cognitive functioning was assessed by psychometric tests and real-world problem-solving tasks. Prior functioning was indexed by crystallized ability measures. QoL was assessed using the Leiden-Padua questionnaire (LEIPAD), Faces scales and Hospital and Anxiety Depression Scale. A single QoL factor was derived. RESULTS: Simultaneous multiple regressions indicated that QoL was related to real-world but not to abstract problem-solving ability. Separate contributions to QoL were also found for health and self-rated cognitive functioning. CONCLUSIONS: The present study replicates previous findings that abstract problem-solving ability is not related to QoL and supports the hypothesis that real-world or everyday problem-solving ability is associated with QoL in older people.

The evaluation of suspected ulnar neuropathy at the elbow. Normal conduction study values.

Local compression of the ulnar nerve occurs at several points, with the elbow region being the most common. Nerve conduction studies can be useful in identifying and localizing such lesions; however, the specifics of the technique, including normal values, have not been firmly established. We evaluated the effect of elbow position on segmental conduction velocities (CVs), the influence of elbow, nerve segment length on CV calculations, the change in compound action potential amplitude at sites along the nerve, and the use of performing segmental sensory CVs. Conductions done with the elbow flexed produced less segment-to-segment CV variation than those obtained with the elbow extended. The influence of using overlapping nerve segments compared with short adjacent ones for segmental CV comparison is discussed.

Granulomatous inflammatory myopathy associated with myasthenia gravis. A case report and review of the literature.

A 76-year-old woman with a history of granulomatous pulmonary disease presented with myasthenia gravis involving ocular, pharyngeal, and proximal extremity weakness. She responded to prednisone therapy but three years later developed predominantly distal appendicular weakness. Reinvestigation demonstrated a granulomatous inflammatory myopathy.

Familial long thoracic nerve palsy: a manifestation of brachial plexus neuropathy.

Long thoracic nerve palsy causes weakness of the serratus anterior muscle and winging of the scapula. It is usually traumatic in origin. Isolated long thoracic nerve palsy has not been recognized as the major manifestation of familial brachial plexus neuropathy, but I have studied the syndrome in four members of three generations of one family. One individual suffered an episode of facial paresis. The inheritance pattern was autosomal dominant.

Lumbosacral spinal evoked potentials in humans.

Evoked potentials in response to submaximal electrical stimuli to the peroneal or tibial nerves were recorded from the lumbosacral region in 18 normal subjects. Averaging of 128 responses from recording electrodes over spinous processes S1 to T11, with a reference electrode on the contralateral iliac crest, demonstrated potentials of 0.5 to 1.8 microV, with two well-defined negative peaks having latencies proportional to the distance between the stimulating and recording electrodes. The first peak originated from a traveling wave of depolarization in afferent fibers in the cauda equina, and the second peak originated in the spinal cord. F waves, H reflexes, microreflexes, and volume-conducted muscle responses did not contribute to these potentials.

Autoantibodies to GABAergic neurons and response to plasmapheresis in stiff-man syndrome.

Stiff-man syndrome is a rare disorder of unknown etiology in which progressive rigidity, spasms, and continuous motor unit activity may be due to dysfunction of GABAergic inhibition of alpha motor neurons. Some patients with this disorder have evidence of autoantibodies reactive with glutamic acid decarboxylase (GAD). We describe a patient with progressive stiff-man syndrome and high titers of GAD-like immunoreactivity in serum but not spinal fluid. Plasmapheresis resulted in lowered antibody titers, decreased exteroceptive reflex responses, reduced motor unit activity, and marked clinical improvement. Immunohistochemistry using patient serum and plasma produced specific labeling of human and experimental animal tissue consistent with GABAergic neurons and terminal fields. This antibody response was not present in samples from more than 200 other patients. These results provide additional evidence of an autoimmune mechanism for stiff-man syndrome and indicate plasmapheresis may be beneficial in some patients.

Epidemiologic evidence for a changing natural history of myasthenia gravis.

OBJECTIVE: To survey the epidemiologic literature for evidence of an increasing prevalence of myasthenia gravis (MG) over time, and to explore the reasons for the increase. DATA SOURCES: We found population-based reports of the epidemiology of MG by searching bibliographic databases. We used MG, epidemiology, prevalence, incidence, and mortality as search terms. STUDY SELECTION: We included population-based studies that reported the number of cases and the time period from which rates were calculated. STATISTICAL METHODS: We performed a regression analysis of rates versus date of study, comparing the slopes of regression lines for prevalence, incidence, and mortality. We performed a second analysis grouping rates by decade of study and calculating a mean rate weighted by the size of the population studied. We calculated 95% confidence intervals for each rate. RESULTS: We included 33 studies from 1950 through 1995. Prevalence and incidence rates increased over time, but the regression line for prevalence significantly exceeded that for incidence. Mortality rates declined slightly. The weighted means for prevalence rose significantly, but there was no significant change in incidence or mortality. CONCLUSION: The prevalence of MG has increased over the past forty-five years, probably because patients with the disease have longer life spans owing to present-day treatment.

Trends in the association of Lambert-Eaton myasthenic syndrome with carcinoma.

The Lambert-Eaton myasthenic syndrome (LEMS) is often associated with carcinoma. The exact number of patients with tumor has been reported to be as high as 70%. Recent clinical experience suggests that the actual number of patients with tumor may be substantially lower. We combined data from the clinical experience of the neuromuscular services at West Virginia University and the University of Virginia to determine the rate of occurrence of cancer in this disorder. We identified 28 patients with LEMS, and 14 had cancer. There is a distinct trend for a lower tumor frequency over the past decade, which suggests that the clinical manifestations of the disease may be changing.

Somato-somatic referred pain caused by suprasegmental spinal cord tumor.

Tactile stimulation of a coin-sized area in a T-2 dermatome consistently triggered a lancinating pain in the ipsilateral C-8 dermatome in a 38-year-old woman. The SEP and an MRI led to a diagnosis of a tumor at the left cervico-medullary junction, much higher than the clinically suspected level. Surgical exploration revealed an exophytic glioma, and the pain was abolished postoperatively. Ephaptic transmission at the tumor site was suspected as a pathophysiologic mechanism.

Familial autoimmune myasthenia gravis and thymoma: occurrence in two brothers.

At ages 31 and 42 years, two brothers presented with clinical, pharmacologic, electrophysiologic, and immunologic characteristics of autoimmune myasthenia gravis. At thymectomy, both had histologic findings of epithelial thymoma. HLA analysis revealed A2, A3, B7, and B39 antigens in one patient and A3, A24, B7, and B40 antigens in the other. Familial myasthenia gravis with thymoma has not been described previously. Familial thymoma has been rarely reported, but never with myasthenia gravis.

Hereditary motor-sensory neuropathy (HMSN): possible X-linked dominant inheritance.

The inheritance of the hereditary motor and sensory neuropathies (HMSN) is usually autosomal dominant. We studied a kinship with a pattern of X-linked dominant inheritance. The phenotype was similar to HMSN of the "intermediate" type. Men were more severely affected than women, and hypertrophic nerves were not found. Nerve conduction was very slow in men, but it was mildly slow or normal in women. No male-to-male transmission was found in six generations.

The unchanging pattern of subarachnoid hemorrhage in a community.

The average annual incidence of subarachnoid hemorrhage (SAH) from aneurysm rupture in Rochester, Minnesota, has remained remarkably constant at about 11 per 100,000 population. Age-specific incidence increased with age. Survival after SAH depended on: (1) clinical grade, (2) time after onset of SAH, and (3) presence of intracerebral hematoma. Among those who survived to receive medical attention, 48% were clinical grade 1 or 2, 20% were grade 3, and 32% were grade 4 or 5. Proved rebleeding occurred within 10 days of the first SAH in 20% of patients who survived until hospital admission.

Iodinated contrast agents in myasthenia gravis.

Administration of intravenous iodinated contrast agents has been reported to cause increased weakness in myasthenia gravis (MG) patients. We reviewed the records of 136 patients with MG who had at least one radiologic procedure involving intravenously administered contrast media. Seven patients (5.1%) had contrast reactions, which compares with the 5% rate of contrast reactions in the general population. Five patients had either a subjective or objective increase in weakness that could be explained by reasons other than contrast administration. Only one patient was found to have increased respiratory muscle weakness, which could have been attributed to either contrast infusion or pulmonary embolism. We conclude that intravenous contrast agents are not contraindicated in MG, but extra care should be taken when they are given.

The epidemiology of myasthenia gravis in central and western Virginia.

We conducted a study of the epidemiology of myasthenia gravis (MG) in four locations in central and western Virginia from 1970 through 1984. The population surveyed was 555,851 in 1984. A total of 73 new cases of MG occurred during the survey period, producing an overall average annual incidence rate of 9.1 per million. The point prevalence rate in 1980 was 13.4 per 100,000, and in 1984 it was 14.2. Approximately 15% of the population was black, and we found that incidence and prevalence rates for the black population were higher than the corresponding white population. When the population was subdivided into <50 and 50+ age groups, the incidence and prevalence were significantly higher in the older group. The rates we report here are higher than rates reported from any other locality. The reasons for the higher rates include optimal case identification, survey of a population with a higher incidence, and increasing aging of the population.

Neuroendocrine lung tumors and disorders of the neuromuscular junction.

We report four cases of Lambert-Eaton myasthenic syndrome (LEMS) or myasthenia gravis (MG) associated with pulmonary neuroendocrine carcinoma having prolonged survival. The tumors were atypical carcinoid or large cell neuroendocrine carcinoma. LEMS is associated with several neuroendocrine carcinomas. Because some neuroendocrine carcinomas have a better prognosis, aggressive tissue diagnosis of lung cancer in LEMS is warranted. Whether the association between MG and atypical carcinoid is a significant co-occurrence is uncertain.

Isolated musculocutaneous neuropathy caused by a proximal humeral exostosis.

We report an isolated musculocutaneous neuropathy caused by a proximal humeral osteochondroma that became symptomatic after the patient played recreational basketball. Lesion resection resulted in complete deficit resolution. Mass lesions involving the musculocutaneous nerve should be considered in patients with atraumatic, isolated musculocutaneous neuropathies that are recurrent or fail to recover, even in the setting of strenuous exercise.

Aneurysmal subarachnoid hemorrhage: timing of surgery and mortality.

In contrast to the incidence of other types of stroke, the incidence of aneurysmal subarachnoid hemorrhage has not changed. It is highest in the oldest age groups, and this indicates that it is not due to a congenital lesion. The primary factors that affect survival after aneurysmal subarachnoid hemorrhage are the clinical grade of the patient and the duration of time from onset to the time the patient is seen for medical attention. Because of the very high early mortality from aneurysmal subarachnoid hemorrhage, surgeons generally wait until 10 to 14 days before undertaking surgery. This delay results in a lower surgical mortality but makes it difficult to show an effect on overall mortality. Increasing attention is being given to early surgery after aneurysmal subarachnoid hemorrhage.

Midlife aging, open-ended planning, and laboratory measures of executive function.

The frontal lobes show early signs of structural and functional change in the course of adult aging. The 1st study of the current article examined whether midlife aging influences open-ended planning, a skill that is particularly sensitive to frontal lobe damage. There were no midlife declines in the ability to carry out variants of the T. Shallice and P. Burgess (1991) Six Elements and Multiple Errands Tests. Younger adults were more likely to break individual task rules. In a 2nd experiment, middle-aged adults performed worse than young adults did on laboratory executive tests sensitive to frontal lobe damage-Self-Ordered Pointing and the Wisconsin Card Sorting Test (N. M. Fristoe, T. A. Salthouse, & J. L. Woodard, 1997). In spite of changes in novel executive test performance, real-world executive skills appear to be spared in midlife aging.

Lambert-Eaton myasthenic syndrome: the lack of short-term in vitro effects of serum factors on neuromuscular transmission.

Serum was obtained from 7 patients with the Lambert-Eaton myasthenic syndrome (LES), 3 patients with small-cell carcinoma of the lung (SCCL), and 9 healthy control subjects. Serum samples were applied in vitro to the rat neuromuscular junction (for 1-3 h for control LES sera; 4 h for SCCL sera), following which the pre- and postjunctional physiological effects of serum factors were studied in the presence of 10 mM [Mg2+]o. All sera produced a marked reduction in the frequency of spontaneous miniature end-plate potentials (MEPPs), while causing slight to moderate changes in MEPP amplitude. There were no consistent changes in the quantum content of the impulse-evoked end-plate potentials, though the serum from one LES patient significantly and reversibly inhibited the evoked quantal release. No significant effect was found when a human intercostal muscle was exposed to serum from another LES patient for 2 h. Therefore, when applied in vitro on a short-term basis, the putative LES autoantibodies do not consistently react with voltage-dependent calcium channels in the motor nerve terminal and thus fail to reproduce the physiologic abnormality of the syndrome. We suggest that the pathogenic IgG molecules may require more than 3h of incubation in order to gain access to, and inhibit the function of, the prejunctional Ca2+ channels.

The frequency of intradural conjoined lumbosacral dorsal nerve roots found during selective dorsal rhizotomy.

The frequency of occurrence of conjoined nerve roots (CR) in the cauda equina has been reported to range from 0.3% to 2%. We found intradural conjoined nerve roots in 13 of 123 (10.6%) patients undergoing selective dorsal rhizotomy for spasticity due to cerebral palsy. The anomaly occurred most commonly at L5-S1 and S1-S2. There was no consistent relationship to other anomalies of segmental anatomy. Our finding of a significantly higher number of conjoined nerve roots in these patients is primarily due to the surgical exposure of the entire cauda equina. This anomaly is more common than previous reports have indicated.