Hemodialysis-related headaches

BACKGROUND/AIM: Hemodialysis (HD) is a therapeutic procedure used to partially correct homeostatic disorders and prevent complications of uremia to appear in the terminal stage of renal insufficiency. The aim of this study was to evaluate and analyze the incidence and features of haedaches in patients undergoing hemodialysis. METHODS: A total of 143 patients, 50 women and 93 men, undergoing hemodialysis, were questionned about their problems with headache using a questionnary designend according to the diagnostic criteria of the Intemational Headache Classification of Headache Disorders from 2004. The patients were separated into two groups: the patients without headache and the patients with repeated headaches. Afterwards, the patients with headaches were further divided into subgroups: the patients who had the headaches before the beginning of HD and patients who experienced repeated headaches with the beginning of HD headache (HDH). In the group of patients with headaches we analyzed characteristics of headache according to which diagnoses of headaches were made, as well as the effects of HD on headaches. We also analyzed features of HDH. The patients with headache were compared to the patients without haedache regarding sex, age, duration of HD, causes of end-stage renal disease, arterial diastolic and systolic blood pressure and serum concentration of hemoglobin, urea nitrogen, creatinine, sodium and potassium. The results were statistically compared. RESULTS: In the group of 143 patients examined, 27 (18.9%) patients had headaches. There were no statistically significant differences between the group of patients with headaches and those without headache regarding to sex, age, duration of HD, causes of end-stage renal disease, serum concentration of hemoglobin, urea nitrogen, creatinine, sodium and potassium. The patients with headaches showed significantlly higher mean values of systolic blood pressure during HD in comparison to the patients without headaches (p = 0.029). There was no statistically significant difference between the two groups regarding the mean values of diastolic blood pressure. Nineteen (13.3%) patients had had headache before starting HD. HD did not have any effect on the characteristics of headaches in more than a half of these patients. In 8 (5.6%) patients we diagnozed HDH using the diagnostic criteria of the International Headache Classification of Headache Disorders from 2004. HDH showed similar caracteristics in all the patients: it appeared mostly in men, during the 4th hour of HD, lasted less than four hours, it was localized bilaterally in the frontal parts of the head, strong in intensity, throbbing and without the associated symptoms. CONCLUSION: The results of our study clearly showed that HDH was a particular entity of headache, not only because of its connenction with HD, but because it had similar characteristics in all the patients in wich it had appeared. Finding out the pathophysiological mechanisms of their occurrence would significantly improve the quality of life style of patients on hemodialysis.     

Steroids inhibit nicotinic acetylcholine receptors.

Application of progesterone to Xenopus oocytes expressing a cloned neuronal nicotinic acetylcholine (nAChR) revealed two effects. The first effect was a fully reversible reduction of the current induced by acetylcholine (ACh), its onset being nearly instantaneous. The second effect, which developed in a few hours, was an irreversible suppression of ACh-evoked currents. The transient inhibition had an apparent Ki of 7 microM when tested with 50 nM ACh, but the percentage of inhibition was positively correlated to the ACh concentration. A reduction of ACh-induced currents which appeared immediately upon progesterone application was also observed with muscle nAChR expressed in oocytes and with nAChR on membrane patches isolated from ciliary ganglion neurons. Thus nAChRs are modulated by progesterone and steroids may play an important role in nicotinic cholinoception.     

Magnetic stimulation of the motor cortex in healthy persons]

In 49 healthy volunteers the motor cortex was stimulated transcranially by the intensive short magnetic field and the responses of the m. abductor digiti minimi (m. ADM) in 20 volunteers were recorded and of the m. tibialis anterior (m. TA) in 29 volunteers in relaxation and in mild contraction. In all volunteers by the electric stimulation of the ulnar nerve in the region of the wrist and the peroneal nerve in the region of the fibular capitulum there have been measured the F wave latency, distal latency of M responses and the conduction time of the peripheral motor neuron has been calculated. The difference between the latency of m. ADM and n. TA responses and the conduction time of the peripheral motor nerve represented the central motor conduction time from the motor cortex to the motor neurons of the anterior horns of the spinal cord (C8 and L4 segments). The normative values of the absolute latencies of the muscle responses and the central motor conduction time in the relaxed and contracted muscle are calculated as well as the normatives of the normal differences in latencies and the central motor conduction time between the left and right side of the same subject.     

Reduced HIV transmission at subsequent pregnancy in a resource-poor setting

Several studies indicate that HIV-infected women continue to have children. We set out to determine the trend in HIV transmission at subsequent pregnancies. From 2002-2003, pregnant women were enrolled in a single dose nevirapine-based Prevention of Mother-to-Child Transmission of HIV (PMTCT) programme. Six years later, women with subsequent children in this cohort were identified and their children's HIV status determined. From 330 identified HIV-infected mothers, 73 had second/subsequent children with HIV results. Of these, nine (12.3%, 95% confidence interval [CI]: 4.6-20.1%) children were HIV-infected. Of the 73 second children, 51 had older siblings who had been initially enrolled in the study with definitive HIV results with an infection rate of 17/51 (33.3%, 95% CI: 19.9-46.7). About 35% of the women had been on antiretroviral drugs. These results demonstrate lower subsequent HIV transmission rates in women on a national PMTCT programme in a resource-poor setting with the advent of antiretroviral therapy.