The burden of headache disorders in India: methodology and questionnaire validation for a community-based survey in Karnataka State

Primary headache disorders are a major public-health problem globally and, possibly more so, in low- and middle-income countries. No methodologically sound studies of prevalence and burden of headache in the adult Indian population have been published previously. The present study was a door-to-door cold-calling survey in urban and rural areas in and around Bangalore, Karnataka State. From 2,714 households contacted, 2,514 biologically unrelated individuals were eligible for the survey and 2,329 (92.9 %) participated (1,103 [48 %] rural; 1,226 [52 %] urban; 1,141 [49 %] male; 1,188 [51 %] female; mean age 38.0 years). The focus was on primary headache (migraine and tension-type headache [TTH]) and medication-overuse headache. A structured questionnaire administered by trained lay interviewers was the instrument both for diagnosis (algorithmically determined from responses) and burden estimation. The screening question enquired into headache in the last year. The validation study compared questionnaire-based diagnoses with those obtained soon after through personal interview by a neurologist in a random sub-sample of participants (n = 381; 16 %). It showed high values (>80 %) for sensitivity, specificity and predictive values for any headache, and for specificity and negative predictive value for migraine and TTH. Kappa values for diagnostic agreement were good for any headache (0.69 [95 % CI 0.61–0.76]), moderate (0.46 [0.35–0.56]) for migraine and fair (0.39 [0.29–0.49]) for TTH.The survey methodology, including identification of and access to participants, proved feasible. The questionnaire proved effective in the survey population. The study will give reliable estimates of the prevalence and burden of headache, and of migraine and TTH specifically, in urban and rural Karnataka

EEG seizure in bilateral ECT is different between low and high stimulus doses

Melancholic depressive patients referred for ECT were randomized to receive either low dose (n = 20) or high dose (n = 20) stimulus applied bifrontotemporally. The two stimulus groups were comparable on the clinical variables. The EEG seizure was recorded on two channels (right and left frontal), digitized, coded and analyzed offline without knowledge of ECT parameters. EEG seizure was of comparable duration in the two stimulus (high dose and low dose) groups. A new composite measure, Strength-Symmetry-Index (SSI), based on strength and symmetry of seizure EEG was computed using fractal geometry. The SSI of the early-seizure was higher in the high dose than in the low dose ECT group. In a stepwise, logistic regression model, this variable contributed to 65% with correct classification of high dose and low dose ECT seizures

Sensory gating impairment in development of post-concussive symptoms in mild head injury.

Post-concussive symptoms reported by mild head injury (MHI) patients have been inadequately understood. Post-concussive symptoms reported by patients with MHI have so far been explained in terms of impairment in neurocognitive functions or deficits in modulation of flow of information. There are no studies that have looked into sensory gating impairment in MHI and its relation to post-concussive symptoms. The purpose of the present paper was to investigate the role of sensory gating impairment in post-concussive symptoms in mild head injury patients. Thirty MHI patients were evaluated for their neuropsychological functions, sensory gating deficits, and post-concussive symptoms. Neuropsychological functions were in the domain of attention, executive functions, and learning and memory. Sensory gating was assessed by Structured Interview for Assessing Perceptual Anomalies and post-concussive symptoms were assessed using the Neurobehavioral Rating Scale. Multiple regression method was used to identify predictors for post-concussive symptoms. Post-concussive symptoms were predicted by sensory gating deficits when sensory gating deficit was one of the predictors along with neuropsychological functions. Post-concussive symptoms were predicted by scores of Digit Vigilance and Digit Symbol Substitution Test, when predictors were restricted to neuropsychological functions. Sensory gating deficits were correlated with performance on Digit Symbol Substitution test. Post-concussive symptoms reported by MHI patients are the result of poor modulation of incoming sensory information