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Flemming W Bach

Publications and source records attributed to Flemming W Bach.

24 records · Page 2Linked to original sources

Pain in patients with multiple sclerosis: a population-based study.

BACKGROUND: Pain is an important symptom in patients with multiple sclerosis (MS). The estimated pain prevalence varies between 30% and 90%. To our knowledge, previous studies do not include a whole population sample of patients with MS. OBJECTIVE: To assess pain prevalence and its clinical characteristics and impact on daily life in a population sample of MS patients and in a reference group. DESIGN: Postal survey. SETTING: Aarhus County, Denmark. PARTICIPANTS: The population of patients with definite MS in Aarhus County (n = 771) and a sex- and age-stratified reference group from the general population (n = 769). MAIN OUTCOME MEASURES: Pain prevalence, intensity, and treatment requirement; and the impact of pain on daily life. RESULTS: Response rates for MS patients and reference subjects were 81.3% and 63.3%, respectively. Pain in the month preceding assessment occurred in 79.4% of MS patients and in 74.7% of reference subjects (prevalence proportion ratio, 1.06; 95% confidence interval, 0.99-1.13). Patients with MS had a higher pain intensity ("when pain is at its least" median visual analog scale score, 20.0 vs 11.0 mm [P<.01];and "when pain is at its worst" median visual analog scale score, 68.0 vs 55.0 mm [P<.01]). Daily intake of analgesics occurred in 24.4% of MS patients and 9.0% of reference subjects (prevalence proportion ratio, 2.7; 95% confidence interval, 2.0-3.6). Patients with MS more often reported that pain interfered with daily life "most of the time" or "all the time." CONCLUSIONS: The frequency of reported pain in MS patients was not higher than in the background population. However, pain intensity, the need for analgesic treatment, and the impact of pain on daily life were higher in MS patients.

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Pain phenomena and possible mechanisms in patients with painful polyneuropathy.

Painful polyneuropathy is a common neuropathic pain condition characterized by different typical pain phenomena and symptoms. The present study determined the frequency of pain phenomena and signs in painful polyneuropathy, and compared the symptomatology in patients with signs of increased small fiber response with that in patients with signs of deafferentation. Eighty-one consecutive patients with painful polyneuropathy were studied. The most common pain phenomena were deep aching pain (88%) and pain on pressure (69%), followed by pain paroxysms (59%) and less frequently pain on light touch (31%). Patients with increased cold and heat detection thresholds were more likely to have pain paroxysms (odds ratio (OR) 2.5 and 5.2) and patients with pain summation on repetitive mechanical stimulation more often had touch-evoked pain (OR=4.0) than patients without these phenomena. Findings compatible with increased small fiber response were found in six patients (7.4%), in 41 (50.6%) unequivocal signs of deafferentation were found, and 34 patients (42%) could not be classified. There was no significant difference in presenting symptoms between these groups. In conclusion, in painful polyneuropathy, (1). deep aching pain is the most frequently reported pain symptom; (2). the association between pain paroxysms with decreased small fiber function and touch-evoked pain with abnormal pain summation on mechanical stimulation indicate that central nervous system mechanisms are responsible for these symptoms; (3). sensitized small fibers as the single mechanism of pain is rare; and (4). pain symptomatology cannot predict pain mechanisms as being mainly deafferentation or sensitized small fibers.

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Lamotrigine in spinal cord injury pain: a randomized controlled trial.

The objective was to investigate the effectiveness of lamotrigine for the treatment of spinal cord injury pain and clinical signs of neuronal hyperexcitability. Thirty patients with spinal cord injury (SCI) and at or below level neuropathic pain participated in a randomized double blind, placebo-controlled, crossover trial. A 1-week baseline period was followed by two treatment periods of 9 weeks duration with lamotrigine slowly increased to a maximum of 400 mg or placebo separated by a 2-week washout period. The primary outcome measure was the change in median pain score from baseline week to the last week of treatment. Secondary outcome measures included thresholds to standardized sensory stimuli using quantitative sensory testing. Twenty-two patients completed the trial. We found no statistically significant effect of lamotrigine as evaluated in the total sample. However, in patients with incomplete SCI, lamotrigine significantly reduced pain at or below SCI level. Patients with brush evoked allodynia and wind-up-like pain in the area of maximal pain were more likely to have a positive effect to lamotrigine than patients without these evoked pains (7 of 7 vs. 1 of 14). Lamotrigine was generally well tolerated. While this trial showed no significant effect on spontaneous and evoked pain in complete and incomplete spinal cord injury, lamotrigine reduced spontaneous pain in patients with incomplete spinal cord injury and evoked pain in the area of spontaneous pain.

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St. John's wort has no effect on pain in polyneuropathy.

Tricyclic antidepressants are the mainstay of treatment of painful polyneuropathy but cannot be used in a substantial number of patients. St. John's wort is a herbal antidepressant, which may act via mechanisms similar to the tricyclics. The aim of this study was to test if St. John's wort would relieve painful polyneuropathy. The study design was randomized, double-blind, placebo-controlled and cross-over. Fifty-four patients were assigned to one of the two treatment sequences. The daily dose of St. John's wort was three tablets each containing 900 microg totalhypericin. During the two treatment periods of 5 weeks duration, patients rated constant pain, lancinating pain paroxysms, touch-evoked pain and pain on pressure by use of 0--10 point numeric rating scales. Forty-seven patients -- 18 diabetics and 29 non-diabetics -- completed the study. There was a trend of lower total pain score (sum of the individual pain scores) on St. John's wort than on placebo (median 14 vs. 15, P=0.05). None of the individual pain ratings were significantly changed by St. John's wort as compared to placebo (P=0.09--0.33). Complete, good or moderate pain relief was experienced by nine patients with St. John's wort and two with placebo (P=0.07). In conclusion, St. John's wort has no significant effect on pain in polyneuropathy.

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Plasma and cerebrospinal fluid beta-endorphin in chronic tension-type headache.

Previous studies have provided evidence of an increased sensitivity to pain, a decreased hypothalamic opioid tone, and decreased cerebrospinal fluid (CSF) beta-endorphin (beta-EP) concentration in patients with primary chronic headache. We applied separate specific radioimmunoassays for beta-EP in CSF and plasma on samples from age-matched controls and a group of 50 patients with chronic tension-type headache (CTH) fulfilling the diagnostic criteria set by the International Headache Society. Median CSF beta-EP concentrations (95% confidence limits) were 12.8 pmol/l (11.0-14.5) in CTH patients and 11.9 pmol/l (10.9-14.2) in the control group, which is not significantly different (P = 0.28). Plasma beta-EP concentrations did not differ either, being 3.1 pmol/l (2.4-3.7) and 3.3 pmol/l (1.8-4.0) in the patients with CTH and in controls, respectively (P = 0.88). Plasma and CSF beta-EP concentrations did not correlate. Reversed-phase high performance liquid chromatography (HPLC) of CSF pools from the headache patients and controls revealed similar profiles of beta-EP-immunoreactivity both when C-terminally and N-terminally directed antisera were used, suggesting a normal post-translational processing of the pro-opiomelanocortin gene in patients with CTH. beta-EP is not involved in the pathogenesis of CTH, or such a role is not reflected in CSF or plasma concentrations of the neuropeptide.

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The effect of intravenous lidocaine on nociceptive processing in diabetic neuropathy.

In a double-blind controlled design, 7 patients with painful diabetic neuropathy received lidocaine 5 mg/kg or saline intravenously over a period of 30 min. Thermal sensibility quantified by thermotest was not affected by lidocaine. In 3 of the patients nociceptive flexion reflex thresholds could be determined. The threshold was increased by lidocaine and returned to pre-infusion level within 10 days. Lidocaine also increased the threshold in 4 healthy subjects, but did not affect the Hoffmann reflex. These results suggest that lidocaine exerts its pain-relieving effect on the spinal level in diabetic neuropathy.

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