Prevention of recurrent benign paroxysmal positional vertigo with vitamin D supplementation: a meta-analysis.

RESEARCH BACKGROUND: Vitamin D insufficiency/deficiency is known to be related to occurrences and recurrences of benign paroxysmal positional vertigo (BPPV). However, the efficacy of vitamin D supplementation in reducing recurrences of BPPV remains to be established. We performed a meta-analysis to determine the therapeutic effects of vitamin D supplementation, with or without calcium, for preventing recurrences of BPPV. METHODS: We searched the PubMed, the Embase, the Web of Science and the reference lists of the articles. We included randomized or non-randomized trials that determined the efficacy of supplementing vitamin D or related compounds, alone or with calcium, in comparison to placebo or no intervention in preventing recurrences of BPPV. The primary outcome was the number of patients with BPPV recurrences. Data were collected and pooled using a weighted relative risk (RR) with corresponding 95% CIs, where possible, by adopting the fixed-effect or random-effect model according to the heterogeneity among the studies. The between-study heterogeneity was tested using the χ2 test and the I2 statistic, and funnel plots were used to evaluate any publication bias. RESULTS: We included five trials (four non-randomized trials and one randomized controlled trial) with a total of 1250 participants. The analyses showed a significant preventive effect on the recurrences of BPPV (RR = 0.37; 95% CI = 0.18-0.76; p = 0.007 with the random-effects model) with supplementation of vitamin D. Although a considerable heterogeneity was detected among the studies, the sensitivity analyses showed the reliability and stability of our results. CONCLUSIONS: Vitamin D supplementation provides a benefit for secondary prevention of BPPV. Supplementation of vitamin D should be considered in patients with frequent attacks of BPPV, especially when serum vitamin D is subnormal.

Update on benign paroxysmal positional vertigo.

Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo worldwide. This review considers recent advances in the diagnosis and management of BPPV including the use of web-based technology and artificial intelligence as well as the evidence supporting the use of vitamin D supplements for patients with BPPV and subnormal serum vitamin D.

Prevention of benign paroxysmal positional vertigo with vitamin D supplementation: A randomized trial.

OBJECTIVE: To assess the effect of vitamin D and calcium supplementation in preventing recurrences of benign paroxysmal positional vertigo (BPPV). METHODS: We performed an investigator-initiated, blinded-outcome assessor, parallel, multicenter, randomized controlled trial in 8 hospitals between December 2013 and May 2017. Patients with confirmed BPPV were randomly assigned to the intervention (n = 518) or the observation (n = 532) group after successful treatment with canalith repositioning maneuvers. The primary outcome was the annual recurrence rate (ARR). Patients in the intervention group had taken vitamin D 400 IU and 500 mg of calcium carbonate twice a day for 1 year when serum vitamin D level was lower than 20 ng/mL. Patients in the observation group were assigned to follow-ups without further vitamin D evaluation or supplementation. RESULTS: The intervention group showed a reduction in the ARR (0.83 [95% confidence interval (CI), 0.74-0.92] vs 1.10 [95% CI, 1.00-1.19] recurrences per 1 person-year) with an incidence rate ratio of 0.76 (95% CI, 0.66-0.87, p < 0.001) and an absolute rate ratio of -0.27 (-0.40 to -0.14) from intention-to-treat analysis. The number needed to treat was 3.70 (95% CI, 2.50-7.14). The proportion of patients with recurrence was also lower in the intervention than in the observation group (37.8 vs 46.7%, p = 0.005). CONCLUSIONS: Supplementation of vitamin D and calcium may be considered in patients with frequent attacks of BPPV, especially when serum vitamin D is subnormal. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with BPPV, vitamin D and calcium supplementation reduces recurrences of BPPV.

Impaired Calcium Metabolism in Benign Paroxysmal Positional Vertigo: A Topical Review.

BACKGROUND AND PURPOSE: Although acute attacks of benign paroxysmal positional vertigo (BPPV) may be treated with canalith repositioning maneuvers, there have been no well-designed prospective trials to prevent this highly prevalent and recurrent disorder. This topical review explores the evidence related to the association between deficient calcium metabolism and BPPV. We also describe the development of therapeutic options to prevent recurrences of BPPV and introduce results from a recent randomized controlled trial on the effect of vitamin D and calcium supplementation in preventing BPPV recurrences. SUMMARY OF KEY POINTS: The literature describes 3 lines of evidence on association of impaired calcium metabolism and development of BPPV: (1) decreased bone mineral density was more frequently observed in persons with BPPV than in healthy controls; (2) estrogen plays a vital role in maintenance of otoconia, and estrogen deficiency appears to precipitate degeneration of otoconia and development of BPPV; and (3) lower serum vitamin D level is associated with development of BPPV, and supplementation of vitamin D and calcium carbonate may reduce further attacks of BPPV in persons with BPPV and subnormal serum vitamin D level. RECOMMENDATIONS FOR CLINICAL PRACTICE: Restoration of impaired calcium metabolism with supplementation of vitamin D or estrogen should be considered in the treatment of individuals with frequent recurrences of BPPV. Future randomized controlled trials are mandatory to validate these supplementation therapies in individuals with recurrent BPPV.

Factors Associated with Vitamin D Status Among Korean Female Adolescents.

PURPOSE: The prevalence of vitamin D deficiency among female adolescents in South Korea is the highest in East Asia. Therefore, this study aims to identify factors associated with vitamin D status among female adolescents in South Korea. DESIGN AND METHODS: This cross-sectional descriptive study was conducted using a data set from the fifth Korean National Health and Nutrition Examination Survey (2010-2012). Participants comprised 734 female adolescents aged 12-18 years. A general linear model using a complex samples design was employed. RESULTS: The mean vitamin D level of the participants was 14.90 ng/mL. Among these participants, 87.6% had a vitamin D deficiency. As their age increased by one year, their vitamin D level decreased by 0.47 ng/mL. Female adolescents with a low household income had vitamin D levels lower by 1.88 ng/mL than those with a high household income. Vitamin D levels in female adolescents who skipped lunch was lower by 3.41 ng/mL than those who had lunch. CONCLUSION: The prevalence of vitamin D deficiency among female adolescents in South Korea is considerable. The findings suggest that age, socioeconomic status, and skipping a meal were associated with vitamin D status in female adolescents, but physical activity was not. PRACTICE IMPLICATIONS: As the findings of this study indicate, older female adolescents and those from lower household incomes may be at higher risk for lower levels of Vitamin D. Counseling female adolescents as to dietary measures to avoid vitamin D deficiency is advised. Preventive health for at risk female adolescents includes provision of health education and counseling.

Simultaneous recording of cervical and ocular vestibular-evoked myogenic potentials.

OBJECTIVE: To increase clinical application of vestibular-evoked myogenic potentials (VEMPs) by reducing the testing time by evaluating whether a simultaneous recording of ocular and cervical VEMPs can be achieved without a loss in diagnostic sensitivity and specificity. METHODS: Simultaneous recording of ocular and cervical VEMPs on each side during monaural stimulation, bilateral simultaneous recording of ocular VEMPs and cervical VEMPs during binaural stimulation, and conventional sequential recording of ocular and cervical VEMPs on each side using air-conducted sound (500 Hz, 5-millisecond tone burst) were compared in 40 healthy participants (HPs) and 20 patients with acute vestibular neuritis. RESULTS: Either simultaneous recording during monaural and binaural stimulation effectively reduced the recording time by ≈55% of that for conventional sequential recordings in both the HP and patient groups. The simultaneous recording with monaural stimulation resulted in latencies and thresholds of both VEMPs and the amplitude of cervical VEMPs similar to those found during the conventional recordings but larger ocular VEMP amplitudes (156%) in both groups. In contrast, compared to the conventional recording, simultaneous recording of each VEMP during binaural stimulation showed reduced amplitudes (31%) and increased thresholds for cervical VEMPs in both groups. CONCLUSIONS: The results of simultaneous recording of cervical and ocular VEMPs during monaural stimulation were comparable to those obtained from the conventional recording while reducing the time to record both VEMPs on each side. CLINICALTRIALSGOV IDENTIFIER: NCT03049683.

Hierarchical Statistical Models to Represent and Visualize Survey Evidence for Program Evaluation: iCCM in Malawi.

Policy and Program evaluation for maternal, newborn and child health is becoming increasingly complex due to changing contexts. Monitoring and evaluation efforts in this area can take advantage of large nationally representative household surveys such as DHS or MICS that are increasing in size and frequency, however, this analysis presents challenges on several fronts. We propose an approach with hierarchical models for cross-sectional survey data to describe evidence relating to program evaluation, and apply this approach to the recent scale up of iCCM in Malawi. We describe careseeking for children sick with diarrhea, pneumonia, or malaria with empirical Bayes estimates for each district of Malawi at two time points, both for careseeking from any source, and for careseeking only from health surveillance assistants (HSA). We do not find evidence that children in areas with more HSA trained in iCCM are more likely to seek care for pneumonia, diarrhea, or malaria, despite evidence that many indeed are seeking care from HSA. Children in areas with more HSA trained in iCCM are more likely to seek care from a HSA, with 100 additional trained health workers in a district corresponding to a 2% average increase in careseeking from HSA. The hierarchical models presented here provide a flexible set of methods that describe the primary evidence for evaluating iCCM in Malawi and which could be extended to formal causal analyses, and to analysis for other similar evaluations with national survey data.

Altered processing of otolithic information in isolated lateral medullary infarction.

Ocular and cervical vestibular-evoked myogenic potentials (VEMPs) evaluate the function of otolithic pathways in central as well as peripheral vestibular disorders. This study aimed to determine the associations and dissociations of otolithic dysfunction in lateral medullary infarction (LMI), the most well-known disorder of central vestibulopathy. At the Dizziness Clinic of a referral-based University Hospital, 45 patients with isolated LMI (28 men, mean age = 55.6 ± 12.5) had evaluation of the ocular tilt reaction (OTR), tilt of the subjective visual vertical (SVV), and ocular and cervical VEMPs from Janurary 2011 to August 2015 during the acute phase, 1-11 days from the symptom onset (median = 2 days). Almost all (42/45, 93 %) patients showed at least one component of the OTR or SVV tilt that was invariably ipsiversive. In contrast, oVEMPs were abnormal only in 12 (27 %) and cVEMPs in 13 (29 %) patients. Only three patients showed abnormal results in all the tests of the OTR, SVV tilt, and ocular and cervical VEMPs. Abnormal oVEMPs were more common in patients with the OTR than those without (38 vs 6 %, Pearson X 2 test, p = 0.021). In contrast, abnormality of cVEMPs showed no correlation with the presence of OTR (28 vs 31 %, Pearson X 2 test, p = 0.795). In patients with LMI, ipsiversive OTR is invariable, but abnormalities of oVEMPs and cVEMPs were much less common and mostly dissociated even in the patients with abnormal results. This discrepancy in otolithic dysfunction suggests different anatomical substrates and/or dissimilar reciprocal modulation for processing of each otolithic signal in central vestibular structures located in the dorsolateral medulla.

Pulmonary hemorrhage in pediatric lupus anticoagulant hypoprothrombinemia syndrome.

Lupus anticoagulant-hypoprothrombinemia syndrome (LAHPS), a very rare disease that is caused by the presence of antifactor II antibodies, is usually counterbalanced by the prothrombotic effect of lupus anticoagulant (LAC). Patients with LAHPS are treated using fresh frozen plasma, steroids, immunosuppressive agents, and immunoglobulins for managing the disease and controlling hemorrhages. Notably, steroids are the important treatment for treating hypoprothrombinemia and controlling the bleeding. However, some patients suffer from severe, life-threatening hemorrhages, when factor II levels remain very low in spite of treatment with steroids. Here, we report a case of LAHPS in a 15-year-old girl who experienced pulmonary hemorrhage with rapid progression. She was referred to our hospital owing to easy bruising and prolonged bleeding. She was diagnosed with LAHPS that presented with pancytopenia, positive antinuclear antibody, proloned prothrombin time, activated partial thromboplastin time, positive LAC antibody, and factor II deficiency. Her treatment included massive blood transfusion, high-dose methylprednisolone, vitamin K, and immunoglobulin. However, she died due to uncontrolled pulmonary hemorrhage.

Contralateral suppression of distortion-product otoacoustic emissions: a potential diagnostic tool to evaluate the vestibular nerve.

The amplitude of distortion-product otoacoustic emission (DPOAE) is suppressed in one ear when the contralateral ear is subjected to sound stimulation. Contralateral suppression of DPOAE is the phenomenon resulted by the efferent cochlear innervation on the outer hair cells via medial olivocochlear bundle (MOCB) and inferior vestibular nerve. We assumed that DPOAE would not be suppressed by contralateral sound stimulation in patients with vestibular nerve lesion as long as the specific pathway conveying that efferent innervation is affected. To test this hypothesis, we compared the amount of DPOAE contralateral suppression in patients with vestibular neuritis and healthy controls. Twenty healthy volunteers without hearing loss and vestibulopathy, and 13 patients with vestibular neuritis were recruited. DP audiogram was measured without contralateral sound stimulation and then with contralateral sound stimulation (70 dB HL of 2 kHz narrow band noise, NBN). The suppression value of DPOAE was evaluated according to the f2 frequency and was defined as the amount of DPOAE suppression: An-Ao, where An represents the DPOAE amplitude in the presence of contralateral NBN, and Ao represents the DPOAE amplitude in the absence of NBN. Cervical vestibular evoked myogenic potential (cVEMP) was performed in some patients with vestibular neuritis. The suppression values of DPOAE were compared between groups and were analyzed according to the results of cVEMP. The amount of suppression of DPOAE during contralateral sound stimulation was significantly reduced in the patient group compared to control at the f2 frequencies of 1257, 1587, and 2002 Hz (P=0.045, P<0.001, P=0.009, respectively). However, the results of contralateral suppression of DPOAE were not consistent with the results of cVEMP in this study. Efferent cochlear innervation was affected in vestibular neuritis. Evaluation of contralateral suppression of DPOAE can be a potential diagnostic tool to evaluate the functional integrity of the vestibular nerve. Further studies are necessary to clarify this mechanism.

Cervical and ocular vestibular-evoked myogenic potentials in vestibular neuritis: comparison between air- and bone-conducted stimulation.

To clarify the changes of cervical (cVEMP) and ocular (oVEMP) vestibular evoked myogenic potentials induced by air-conducted sound (ACS) and bone-conducted vibration (BCV) in patients with vestibular neuritis (VN), patients with VN (n = 30) and normal controls (n = 45) underwent recording of cVEMP and oVEMP in response to ACS (1,000 Hz, 5 ms, tone bursts) and BCV (500 Hz, short tone burst). Patients with VN showed a high proportion of oVEMP abnormalities in response to both ACS (80.0 %) and BCV at the forehead (Fz, 73.3 %) or the mastoid (76.7 %). In contrast, cVEMPs were mostly normal with both ACS and BCV in the patients. The dissociations in the abnormalities of cVEMP and oVEMP induced by ACS and BCV at the mastoids and at the forehead in patients with VN suggest that oVEMP reflects functions of the superior vestibular nerve and most likely the utricular function. The results of our study suggest that oVEMP induced by either ACS or BCV appears to depend on integrity of the superior vestibular nerve, possibly due to the utricular afferents travelling in it. In contrast, cVEMP elicited by either ACS or BCV may reflect function of the saccular afferents running in the inferior vestibular nerve.

Evolution of abnormal eye movements in Wernicke's encephalopathy: correlation with serial MRI findings.

A 33-year-old woman with Wernicke's encephalopathy (WE) due to poor oral intake after allogeneic stem cell transplantation for acute myeloid leukemia showed a sequential development of bilateral gaze-evoked nystagmus (GEN), rightward gaze palsy, and upbeat nystagmus. Initial MRIs obtained when she had GEN only showed a lesion involving the medullary tegmentum, and follow-up MRIs revealed additional lesions in the pontine and midbrain tegmentum along with development of rightward gaze palsy, and finally bilateral medial thalamus lesions in association with upbeat nystagmus. The evolution of abnormal ocular motor findings and serial MRI changes in our patient with WE provide imaging evidence on relative vulnerability of the neural structures, and on the progression of lesions and ocular motor findings in thiamine deficiency.

Upbeat nystagmus changes to downbeat nystagmus with upward gaze in a patient with Wernicke's encephalopathy.

We describe a patient with Wernicke's encephalopathy who showed spontaneous upbeat nystagmus with decelerating slow phases that changed to downbeat nystagmus during upward gaze and increased during downward gaze. He also showed horizontal gaze-evoked nystagmus and impaired upward smooth pursuit. Magnetic resonance imaging demonstrated symmetric lesions involving the bilateral medial thalami, periaqueductal gray matters and inferior cerebellar peduncles. In this patient, the decelerating slow phases and disobedience to Alexander's law of upbeat nystagmus suggest both deficient (leaky) and unstable neural integrators subserving vertical eye motion. Dysfunction of the interstitial nucleus of Cajal or its descending pathway to the vestibulocerebellum via the paramedian tract cell groups may be responsible for the upbeat nystagmus and its modulation by gazes in our patient with Wernicke's encephalopathy.

Quercetin-3-O-beta-d-glucuronopyranoside (QGC)-induced HO-1 expression through ERK and PI3K activation in cultured feline esophageal epithelial cells.

Heme oxygenase-1 (HO-1) is one of the antioxidant enzymes which help protect against cellular damage. The present study examined the ability of Quercetin-3-O-beta-D-glucuronopyranoside (QGC), flavonoid glucoside extracted from Rumex Aquaticus Herba, to induce expression of HO-1 and analyzed its signaling mechanism in cultured feline esophageal epithelial cells (EEC). Culture of the esophageal epithelial cells from cat was prepared. The data suggested that QGC could result in enhanced antioxidant enzyme defense system via HO-1 expression and Nrf2 translocation involving both the ERK and PI3K-Akt pathways as well as partly PKC pathways in EEC.

Bimedial rectus hypermetabolism in convergence spasm as observed on positron emission tomography.

A 52-year-old man developed vertical gaze palsy, convergence spasm, and convergence-retraction nystagmus due to glioblastoma of the right thalamus. 18F-fluorodeoxyglucose positron emission tomography (PET) inadvertently demonstrated markedly increased metabolism in the medial rectus muscles. The hypermetabolism indicates active contraction of these extraocular muscles due to excessive convergence drive attributed to inappropriate activation or disrupted inhibition of convergence neurons by the diencephalic lesion.

Specificity of "peering at the tip of the nose" for a diagnosis of thalamic hemorrhage.

BACKGROUND: Tonic inward and downward deviation of the eyes ("peering at the tip of the nose") is regarded as a unique feature of thalamic hemorrhage, but the mechanisms of this ocular finding remain obscure. OBJECTIVES: To describe 4 patients who showed tonic inward and downward deviation of the eyes from brainstem or thalamic lesions and to discuss the possible mechanisms involved. DESIGN: Case report. SETTING: Secondary and tertiary referral hospitals. RESULTS: One patient developed alternating esotropia with downward ocular deviation from thalamic hemorrhage compressing the midbrain. Two patients showed multiple infarctions in the territory of the posterior circulation with or without the involvement of the thalamus. Another patient had lateral pontine hemorrhage extending up to the midbrain tegmentum. Ocular bobbing preceded or accompanied tonic ocular deviation in 3 patients. CONCLUSIONS: Tonic inward and downward deviation of the eyes may develop in thalamic or brainstem lesions. Irritation or destruction of the neural structures involved in the vergence and vertical gaze may cause this ocular sign in mesodiencephalic lesions. Skew deviation and esotropia from abduction deficit may be involved in some patients. Ocular bobbing and tonic downward deviation may share a common pathogenesis.