The prevalence of side effects with regular and sustained-release nicotinic acid

PURPOSE

To document the prevalence and nature of the side effects that occur with the use of regular and sustained-release nicotinic acid in everyday clinical practice.

PATIENTS AND METHODS

One hundred and ten patients seen in a private medical clinic who were given 133 separate trials of nicotinic acid during a 5-year period. The occurrence of side effects, particularly those severe enough to warrant discontinuing the drug, were carefully monitored.

RESULTS

Forty-three percent of individuals given regular nicotinic acid and 42% of those given sustained-release nicotinic acid were forced to discontinue the medication because of side effects; some of these side effects necessitating discontinuing nicotinic acid did not occur until the patient had been taking the drug for 1 or 2 years.

CONCLUSION

Nicotinic acid in both regular and sustained-release forms is a powerful drug when used in doses needed to treat lipid disorders and causes disturbing side effects a very high percentage of the time. No one should use nicotinic acid in these doses without continued careful supervision of a physician.

Folate metabolism and neural tube defects

Neural tube defects may due to a number of factors acting on a susceptible embryo. The most widely accepted is a lack of folic acid at a critical time of development. Studies in which folic acid supplements have been given are reviewed. The results of these support the policy of giving folic acid, starting before conception. The metabolism of folate and vitamin B12 is discussed, including specific metabolic disorders; although there is no evidence that these play any part in causing neural tube defects. The special problems that occur among women taking anti-epileptic drugs are also considered. There are slight differences in the recommendations that have been made for supplementation, and further studies are needed before there can be complete agreement.

Apoptosis (programmed cell death) and other reasons for elimination of neurons and axons

Many of the neurons which migrate to the cortex die at an early stage of development. In certain animals many cells die when their task is done; a phenomenon known as programmed cell death, or apoptosis. In humans a far commoner cause is the competition hypothesis: if the axon of the cell does not make contact with the dendrites of the cell in its target area it will die. Then the complexity and number of these synapses is more essential to the function of the brain than the actual number of neurons. Examples are given of the effect of sensory deprivation on the survival of neurons. The withdrawal of neuronal growth factor, and subsequent loss of the axon or cell can be a factor in the fine tuning of neural circuits, and therefore in an improvement in learning and the development of skills. However, it may also account for the diminished plasticity of the nervous system, and its ability to adapt to injury. It has been postulated that these changes contribute to the development of personality. Factors which may be involved include differences in brain development between the sexes; temperamental traits which may have a genetic or prenatal origin; and the effects of sensory perception, including language. Surely there can be no doubt that the results of experience represent the fundamental mechanisms by which the organism adapts to its environment.

Rapid detection of hereditary and acquired platelet storage pool deficiency by flow cytometry

Platelet aggregation is commonly used to investigate patients with possible dense granule storage pool deficiency (delta SPD), but recent studies have shown that this investigation is not specific or sensitive for this disorder. We describe a simple one-step technique to detect mepacrine loaded platelets by flow cytometry and found a good correlation (r = 0.83) between this method and the enumeration of platelet dense granules by conventional fluorescent microscopy. Seven patients with congenital delta SPD had significantly (P < 0.001) reduced mepacrine labelling detected by flow cytometry (mean 15%; range 5-23%) compared to normal controls (mean 48%; normal range 32-64%). Six patients with other hereditary platelet disorders had normal mepacrine labelling (mean 49%; range 34-66%) and were clearly distinguished from patients with delta SPD despite similar platelet aggregation patterns. Acquired delta SPD is frequently associated with the platelet function defect described in the myeloproliferative and myelodysplastic disorders (MPD/MDS) and we compared platelet aggregation and mepacrine labelling in 15 of these patients. The results confirm that delta SPD occurs commonly in MPD/MDS with 7/15 patients having reduced mepacrine staining but, like the findings in hereditary delta SPD, 3/7 patients with normal platelet aggregation had delta SPD. Similarly abnormal platelet aggregation was not diagnostic of delta SPD as 4/8 of these patients had normal mepacrine levels. These results may contribute to the known lack of correlation between the limited assessment of platelet function and bleeding events in MPD/MDS. We found mepacrine labelling of platelets detected by flow cytometry to be a useful, simple and inexpensive method to detect hereditary and acquired delta SPD which will improve the definition of the platelet defect in these disorders in the clinical laboratory.

Cervical carcinoma in the Grampian region (1980-1991): a population-based study of survival and cervical cytology history

OBJECTIVES

To study survival in women treated for cervical carcinoma in Grampian region, to identify clinical and pathological prognostic factors, and to correlate survival with cytology history.

DESIGN

A retrospective study of all cases of cervical carcinoma using a prospectively gathered database. Data validated by 1 in 10 randomised retrospective case note sampling.

SETTING

Aberdeen Royal Infirmary.

SUBJECTS

Three hundred and sixty-three women resident within Grampian diagnosed as having cervical carcinoma between 1980 and 1991, with five-year survival data on the 206 diagnosed by the end of 1986.

MAIN OUTCOME MEASURE

Five-year survival rates.

RESULTS

The mean annual incidence of cervical carcinoma in our population was 11.2 per 100,000 women, with an overall five-year survival of 67% in those under 40 years of age and 60% in those aged 40 years and over. On univariate analysis, survival was significantly adversely affected by tumour stage, grade and absence of previous smears. On multivariate analysis, the effect of previous smear history was lost, but stage and grade remained strong independent risk factors for survival. There was no significant difference in five-year survival by age or tumour type.

CONCLUSIONS

The prognosis of cervical carcinoma in Grampian region was independently affected only by stage of disease and tumour grading and cervical smear history.

Differences in postoperative pain severity among four ethnic groups

Subjects (N = 543) reporting on acute postoperative dental pain were classified into four major ancestral groups: Asian (N = 96), black American (N = 65), European (N = 296), and Latino (N = 88). Pain severity was measured using a 10-cm visual analogue scale following a standardized operative procedure. The subjects of European descent reported significantly less severe pain than those of black American or Latino descent. They also reported less pain than Asians, although this finding did not reach significance. Evaluation of covariates, including gender, age, education, generation in the United States, and difficulty of the surgical extraction, demonstrated that gender was significant, with men reporting less pain than women regardless of ancestry. Possible implications of these findings are discussed in terms of potential differences in physiology, in addition to social learning.

Muscle and brain disease: an update

A number of syndromes included under this rubric are considered, and their main features discussed. The congenital muscular dystrophy of the Fukuyama type as it occurs in Japan and in the western world are almost certainly the same condition. The muscle disorder is associated with cerebral lesions which may be due to an arrest of neural migration or to demyelination. Muscle, eye and brain disease, or Santavuori's syndrome, shows ocular abnormalities, as well as those of the muscle and brain, as does the Walker-Warburg syndrome. In the latter disorder the cerebral lesions tend to be more severe, and it is more rapidly fatal. The manifestations of all these syndromes undoubtedly overlap, but there has been controversy on the question of their identity. Are they separate entities, or are they different expressions of a similar genetic disorder? The genes for all these conditions will have to be isolated to see if the different phenotypes are alleles of the same gene, or not. Some of the arguments, for and against, are presented.

Review: juvenile myoclonic epilepsy

Juvenile myoclonic epilepsy does not seem to be recognized as often as it should be, accounting as it does for about one in 10 of those with epilepsy. In addition to the myoclonus, absence seizures and tonic-clonic fits can occur. The interictal EEG shows polyspike and wave discharges, and during the myoclonus, medium to high amplitude 16 Hz spikes. Patients may not be seen by a doctor until a major seizure occurs, and if a history of myoclonus is not obtained, inappropriate treatment may be given. The myoclonus may attributed to clumsiness. The inheritance of the condition is most probably polygenic, although it is claimed that juvenile myoclonic epilepsy may be determined by a single autosomal recessive gene. The most effective treatment is with sodium valproate, and this may have to be life-long. In the presence of major seizures carbamazapine should be used with caution as it may exacerbate minor attacks.

The long Q-T syndromes

Loss of consciousness in childhood may be due to cardiovascular causes, and the Long Q-T syndromes can present with seizures. The Romano-Ward syndrome is of autosomal dominant inheritance, and the Jervell and Lange-Nielson syndrome, with associated deafness, of autosomal recessive inheritance. The diagnosis is often delayed, but a careful history can avoid this. The syndromes can appear to be due to an imbalance in the sympathetic nerve to the ventricular myocardium, and precipitating causes such as stress suggest a CNS influence on this. The electrocardiogram can confirm the prolonged Q-T interval, but this is not always present, at least without an exercise test. Treatment with beta-blockers is often successful. If a wrong diagnosis of epilepsy is made a chance may be missed of avoiding sudden death, quite apart from all the medical, and social consequences that can result from such a diagnosis.

Factors associated with early presentation of acute stroke

BACKGROUND AND PURPOSE

Patients with stroke symptoms commonly delay many hours before seeking medical attention. We sought to explore the factors associated with early presentation of stroke patients to physicians.

METHODS

We prospectively studied 100 consecutive acute stroke patients presenting to three large, urban medical centers. Using a standardized, structured interview and chart review, we assessed patient education about stroke, risk factors, clinical features of the stroke, source of stroke recognition, and timing of presentation. We did not study the distance from the site of stroke onset to the site of physician contact.

RESULTS

Stroke onset time was known in 96 of the patients. Mean patient age was 71.3 years, 79% had at least one stroke risk factor, 26% had prior transient ischemic attack, 19% had prior stroke, 74% had some high school education, and 86% had regular physicians. Only 8% had been previously educated about stroke symptoms. Eighty one percent of strokes were ischemic. The mean time to physician contact was 13.4 +/- 2.3 hours (median, 4.0 hours) and to neurologist contact was 21.2 +/- 2.9 hours. A skewed distribution of presentation times accounts for the mean-median differences. A small number of patients presenting very late could have an effect on the correlations between presentation time and the variables studied. Early presentation time was associated with increased age, the sudden onset of a stable deficit, and recognition that the symptoms signified stroke. Only the sudden onset of a stable deficit correlated independently with early presentation time (P = .0048). There was no correlation between presentation time and prior transient ischemic attack or stroke, headache, vomiting, loss of consciousness or seizures at onset, or stroke subtype, but a type II error could not be excluded.

CONCLUSIONS

Despite their education level, regular health care, and risk factors, especially prior stroke and transient ischemic attack, these patients were not knowledgeable about stroke and delayed many hours before contacting physicians. The course of symptoms and recognition that they signified stroke were associated with earlier presentation. Patient education focused on groups at risk may hasten the presentation and treatment of acute stroke.

Whole saliva in systemic lupus erythematosus patients

Whole saliva composition and flow rate were examined in 22 patients with systemic lupus erythematosus and compared with matched healthy controls. Significantly lowered salivary flow rate was observed in patients with systemic lupus erythematosus unrelated to the subjective complaint of xerostomia. Salivary sodium, calcium, and magnesium concentrations were significantly higher in the SLE patients with systemic lupus erythematosus, whereas potassium and total protein concentrations and amylase activity did not differ significantly from the controls. Salivary IgA and IgM levels were significantly higher in the patients than in controls. IgA, IgG, IgM, C3, C4, antinuclear antibody, and anti-DNA antibody levels were measured in serum of the patients with systemic lupus erythematosus and correlated with salivary immunoglobulins. The only significant correlation between saliva and serum was found between levels of salivary IgG and serum anti-DNA antibody. The altered salivary composition might indicate a subclinical involvement of salivary glands in the patients.