Association of folate and vitamin B12 deficiency with vasovagal syncope: a case-control study

Background

Studies demonstrated an association between vitamin B12 deficiency and vasovagal syncope (VVS) in pediatric patients. Moreover, some evidence suggested a pathophysiological role of plasma catecholamines elevation in VVS, which can arise from folate or vitamin B12 deficiency in terms of biochemical pathways.

Purpose

We aimed to evaluate the association of folate and vitamin B12 deficiency with VVS in adults.

Methods

In this case-control study, adult patients (18–70 years of age) with the diagnosis of VVS based on history and physical examination (2018 ESC guidelines) who underwent a head-up tilt test (HUTT) were included as the case group. The control group comprised age- and sex-matched individuals who participated in a population-based cohort study. The most important exclusion criteria were taking vitamin B12 or folate supplements, carbamazepine and phenobarbital, and a history of bariatric surgeries. Plasma levels of vitamin B12, folate, homocysteine, and thyroid-stimulating hormone (TSH), a possible confounder, were measured by Abbott Diagnostics chemiluminescence kits. We compared categorical variables and continuous variables by Chi-square and t-test, respectively. Logistic regression models were employed for adjusting for possible confounders, including age, sex, and TSH.

Results

From February 2020 to February 2021, we screened 157 patients with VVS, of whom 44 patients were included. After matching for age and sex, 44 healthy individuals without a history of syncope were examined as the control group. The mean age was 37.9 years in both groups, with 23 women (52.3%) in each group. Baseline characteristics were comparable across the study groups. There were no significant differences between serum levels of vitamin B12, folate, homocysteine, and TSH, as well as the prevalence of deficiency of folate and vitamin B12 between case and control groups (Table 1), even after adjusting for confounding variables. Serum levels of vitamin B12 were remarkably lower in patients with a lifetime syncopal episodes of ≥3 compared to patients with <3 lifetime attacks (Table 2, P=0.042). This correlation remained statistically significant after adjusting for possible confounders, including age, sex, and TSH by the logistic regression model (P=0.032).

Conclusions

In this study, we found that there is no significant difference between the prevalence of folate and vitamin B12 deficiency and serum levels of these vitamins in adult patients with VVS and healthy individuals; however, serum vitamin B12 was significantly lower in patients with recurrent VVS compared to patients with a lower burden of syncopal episodes. Future studies with larger sample sizes are recommended in the recurrent VVS subgroup. Therapeutic implications of these findings should be investigated in randomized-controlled trials.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Iran National Science Foundation Table 1Table 2

Frequency and predictors of physical trauma during reflex syncope

Background

Reflex syncope is a common and generally benign condition; however, the occurrence of secondary trauma can be a potentially harmful complication. Identification of characteristics and conditions associated with trauma after syncope are important for clinicians.

Purpose

We aimed to investigate the frequency and predictors of secondary injury during reflex syncope in a large dataset from a tertiary syncope unit.

Methods

All patients referred with an episode of transient loss of consciousness between December 2017 and November 2020 were evaluated. Patients who received a diagnosis of reflex syncope based on 2018 European Society of Cardiology guidelines entered the study. Clinical characteristics, conditions surrounding syncope, and – in patients with a history of previous episodes – a detailed history of up to three prior syncopal attacks were documented. The primary outcome was the presence of any clinically relevant injury that was related to syncope. In a secondary per-episode analysis, the outcome was a combination of traumatic injuries related to the current and past syncopal episodes.

Results

Among 1258 consecutive patients with reflex syncope (Mean age: 42.3 years; 49.6% female), 239 (23.3%) had evidence of trauma in their initial visit. Female sex (prevalence ratio [PR]: 1.24; P=0.037), body mass index ≥25 kg/m2 (PR: 1.28; P=0.016), previous injury caused by syncope (PR: 1.63; P<0.001), occurrence of syncope in morning hours (PR: 1.90; P<0.001), occurrence of syncope at home (PR: 1.61; P<0.001), absence of prodromes (PR: 1.32; P=0.024), and standing position at the time of syncope (PR: 1.61; P<0.001) were associated with injury. Although family history of syncope was not related to injury, history of syncope in brother showed a significant association with secondary trauma (PR: 2.19; P=0.003). In multivariable logistic regression, five characteristics (previous injury after syncope, occurrence of syncope in the morning, occurrence of syncope at home, absence of prodromes, and standing position at the time of syncope) were independent predictors of injury. In the absence of all five conditions, the risk of injury was <3%. In the secondary per-syncope analysis, of 2849 syncopal episodes, 1028 (36.1%) were associated with trauma. Having syncope in the morning (PR: 1.34; P<0.001), occurrence of syncope at home (PR: 1.51; P<0.001), absence of prodromes (PR: 1.34; P<0.001), and standing position at the time of syncope (PR: 1.55; P<0.001) were again associated with injury.

Conclusions

Secondary trauma after reflex syncope is a common complication. Specific conditions at the time of syncope are associated with traumatic injuries, suggesting that interventions to avoid syncopal attacks in those conditions might reduce secondary trauma.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Tehran University of Medical Sciences

Impact of supervised physical training on vasovagal syncope; a randomized controlled trial

Background

Therapeutic interventions in vasovagal syncope (VVS) are centered on lifestyle modifications aimed to counteract the recognized mechanisms that precipitate syncope. In patients with recurrent VVS, supervised training might help reduce the symptomatic burden by increasing adherence to lifestyle modifications.

Purpose

We aimed to evaluate the effect of an integrated supervised training program versus standard care on syncopal recurrence rate among patients with VVS.

Methods

This randomized, controlled, 1:1 parallel-design, open-label trial was conducted between November 2019 and February 2021. Eligible patients were those aged between 18 and 70 years with newly-diagnosed medication-naïve VVS who had experienced ≥2 syncopal episodes in the prior year. All participants received education and reassurance about the benign nature of VVS, were advised to increase salt and fluid intake, and practice counter-pressure maneuvers based on 2018 European Society of Cardiology syncope guideline (standard care). Patients were randomized to standard VVS care or the training program. The intervention program consisted of thrice-weekly four-hours-long sessions during the first month after randomization; including tilt training, aerobic exercise (with rowing ergometer, recumbent biking), and standardized counter-pressure maneuvers supervised by a team of physical medicine and rehabilitation specialist and a cardiologist. After the first month, the intervention group were planned to attend a four-hours-long session every three months. The control group were followed by phone calls after the initial visit every three months. The intended follow-up duration was one year and the primary outcome was time to first syncopal episode.

Results

Out of 332 patients screened, 50 (mean age: 33.5 years; 64% female, figure 1) were equally randomized. Follow-up was completed for all participants. After one year, there was a significant reduction in syncope with supervised training compared to standard care (hazard ratio: 0.28; 95% confidence interval: 0.11 to 0.68; p=0.005, figure 2). Furthermore, frequency of syncope was lower in the supervised training arm versus standard of care (median [interquartile range]: 0 [0–1] versus 1 [0–3]; p=0.017).

Conclusions

In patients with recurrent VVS, supervised training showed promising results in reducing syncopal recurrence. Future research should focus on similar approaches to alter patients' lifestyle as an effective treatment for VVS.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Tehran University of Medical Sciences Figure 1Figure 2

Atomoxetine in patients with recurrent vasovagal syncope for preventing vasovagal attacks and improvement of depression and anxiety: a randomized double-blind placebo-controlled clinical trial

Background

Studies showed that sibutramine or reboxetine reduced head-up tilt (HUT)-induced syncope and pre-syncope by 78%. Furthermore, in an open-label series of highly symptomatic patients with vasovagal syncope (VVS), sibutramine reduced frequency of vasovagal spells. In a recent proof of principle study, atomoxetine reduced number of HUT-induced syncopal episodes by about 50% compared to placebo.

Purpose

In this study, we aimed to evaluate the effectiveness of atomoxetine on preventing recurrence of syncopal and pre-syncopal episodes in patients with recurrent VVS after three months of follow-up. Moreover, we determined whether it can improve patients' anxiety and depression.

Methods

In this double-blind placebo-controlled randomized clinical trial, we screened 843 patients with VVS. Patients with 10 < age < 70 years who had ≥3 syncopal episodes in the past three months were included. Eventually, 46 patients were randomized to receive atomoxetine (20 mg daily for two weeks followed by 40 mg daily for two weeks, N=23) or placebo (for four weeks, N=23). The primary endpoint was the number of syncopal and pre-syncopal episodes at one and three months and was analyzed by the repeated measures analysis of variance. Secondary endpoints were decrements of depression and anxiety measured by the Hospital Anxiety and Depression Scale after three months and were analyzed by the Mann-Whitney U test.

Results

The primary endpoint was lower after three months in the atomoxetine arm (2.3±1.3 vs 4.3±1.7), with a significant between-subjects effect by atomoxetine versus placebo (P<0.001). This observation was primarily due to the reduction of pre-syncopal episodes rather than syncopal episodes (P<0.001 vs P=0.944, respectively, Table). In contrast with placebo, atomoxetine significantly improved anxiety (P=0.048 vs P=0.352) and depression (P=0.001 vs P=0.206) after three months; nonetheless, anxiety and depression scores of the patients were not different across the groups after three months (P>0.05, Figure).

Conclusions

In patients with VVS, atomoxetine significantly reduced the recurrence of a composite of syncopal and pre-syncopal episodes, and remarkably improved anxiety and depression at three months.

Anxiety and Depression of the Patients

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Tehran University of Medical Sciences

The role of neutrophil-gelatinase-associated lipocalin in early diagnosis of contrast nephropathy

Neutrophil-gelatinase-associated lipocalin (NGAL) is a biomarker of acute kidney injury. The aim of this study was to define a cut-off for NGAL in the early diagnosis of contrast-induced nephropathy (CIN) in patients with normal kidney function. We enrolled 121 patients with normal serum creatinine who underwent coronary angiography. NGAL was measured in urine before the procedure and 12 and 24 h afterward. CIN was defined as a 0.3 mg/dl increase in serum creatinine within 48 h after the procedure. Seven of 121 patients had CIN (5.8%). The NGAL levels in the 12- and 24-h urine samples of these patients were 30 (5–45) and 20 (15–40) ng/ml, respectively, whereas those in patients without CIN were 15 (5–45) and 15 (10–51) ng/ml, respectively (P = 0.8). In patients with CIN, the sensitivity and specificity of NGAL with a cut-off of 22.5 ng/ml were 71.4% and 57.9% in 12-h urine samples, with the negative predictive values (NPV) and positive predictive values (PPV) of 97.1% and 9.4%, respectively. In conclusion, we suggest that urine NGAL with cut-off point of 22.5 ng/ml has acceptable sensitivity and specificity for early diagnosis of CIN in patients with normal serum creatinine, but regarding NPV and PPV the best performance of this value is to rule out the CIN in patients at risk who received contrast media.

Alterations of the perivascular dystrophin-dystroglycan complex following brain lesions: an immunohistochemical study in rats

Dystroglycan is a laminin receptor, which with dystrophins and other components forms the dystrophin-dystroglycan complex. It has an important role in the formation of gliovascular connections, cerebral vascularisation and blood-brain barrier. Dystroglycan consists of two sub-units, α and β. Previous studies demonstrated that the β-dystroglycan immunoreactivity of cerebral vessels temporarily disappeared in the area adjacent to the lesion, whereas the vascular laminin which is not immunoreactive in the intact brain became detectable. The present study extends these investigations over other components of the complex: utrophin, α1-syntrophin and α1-dystrobrevin. The experiments were performed on adult rats. The lesions were stab wounds or cryogenic lesions in deep ketamine-xylasine narcosis. Following survival periods 2 to 30 days, the animals were perfused and floating brain sections were processed for fluorescent immunohistochemistry. The α1-dystrobrevin, like β-dystroglycan, vanished temporarily around the lesion. The immunoreactivity of utrophin changed in a similar way to that of laminin. In intact brains they were confined to the entering segments of the vessels and to the circumventricular organs. Following lesions their immunoreactivity manifested in the vessels around the lesions. However, utrophin followed laminin with a delay: their peaks were about POD (postoperative days) 21 and 7, respectively. Only immunoreactivity of α1-syntrophin appeared in the reactive astrocytes, peaking at POD 14. Double-labeling proved its co-localization with GFAP. Cryogenic lesions had similar immunohistochemical effects, but provided more suitable samples for Western blot analysis, which proved the altered levels of α1-dystrobrevin and α1-syntrophin. The phenomena may help to monitor the post-lesion vascular processes and the alterations of the gliovascular connections.

Evaluation of hematological and biochemical profiles in dairy cows with left displacement of the abomasum

For the present study, 25 Holstein and crossbreed, 3 to 7-year-old cows diagnosed with left displacement of the abomasum and 15 healthy cattle as control groups over a period of 2 years were used. LDA diagnosis was based on clinical examinations (high-pitched bell-like sounds) and confirmed by laparoscopy. Two blood samples were collected from each case through the jugular vein including one tube containing EDTA for hematological parameters analysis and one tube without anticoagulant for biochemical analysis. Hematological parameters including Ca, P, Mg, Cl, AST, urea, and glucose concentrations were measured by routine procedures. Serum was determined by use of an atomic absorption spectrophotometer, and Na and K values were obtained using a flame photometer. The results of this study showed that Hb, percentage of PCV, total leukocytic, neutrophils, total protein count plus AST, urea, and glucose concentrations were significantly increased in the LDA cases compared to the control group, whereas a marked decrease in plasma electrolyte concentrations (hyponatremia, hypochloremia, hypokalemia, and hypocalcemia) was found in 88–92% of LDA cases. In conclusion, in the present study, it was shown that DA causes alterations in the clinical, hematological, and biochemical profiles and these alterations can be more severe when DA is concurrent with other diseases.

Prevalence of left main coronary artery disease among patients with ischemic heart disease: insights from the Tehran Angiography Registry

AIM

This study was designed to investigate the prevalence of left main coronary artery (LMCA) significant stenosis among patients with stable angina (SA) or acute coronary syndromes (ACSs) and to assess the influence of demographic and clinical profiles on these findings.

METHODS

A review of the Angiography Registry demonstrated that 18137 patients had SA or ACSs. The patients' characteristics were compared in subgroups with and without LMCA disease.

RESULTS

Significant and minimal LMCA stenoses were found in 659 (3.6%) and 1157 (6.4%) patients, respectively. An unprotected LMCA disease was estimated in 609 (3.4%) subjects. A cumulative Logit Model analysis revealed the male gender (odds ratio [OR]=1.480, 95% confidence interval [CI]=1.287 to 1.703; P<0.001), diabetes mellitus (OR=1.158, 95% CI=1.029 to 1.303; P=0.015), dyslipidemia (OR=1.125, 95% CI=1.001 to 1.265; P=0.048), and aging (OR=1.028, 95% CI=1.022 to 1.034; P<0.001) as the independent predictors of LMCA stenosis with coexistent diseases in the rest of the coronary arteries. In the patients with normal or minimal stenoses of the other coronary arteries, cigarette smoking (OR=3.749, 95% CI=1.698 to 8.070) was found to be the independent risk factor of isolated LMCA disease. Luminal stenosis >50% in the right coronary artery, the left circumflex artery, and the left anterior descending artery was significantly more frequent in association with LMCA disease.

CONCLUSIONS

The patients with LMCA disease were more likely to be male, older, and have diabetes mellitus or dyslipidemia, whereas cigarette smoking was found as an independent predictor of isolated LMCA. There was a strong correlation between the severity of LMCA stenosis and coexistent diseases in the rest of the coronary arteries.

Folate, vitamin B12 and homocysteine status in women of childbearing age: baseline data of folic acid wheat flour fortification in Iran

BACKGROUND

Folic acid fortification implemented mandatorily in many countries has been associated with significant increase in blood folate concentrations and reduction in the prevalence of neural tube defects. However, there are controversial findings on the probability of vitamin B(12) deficiency being masked in the population after folic acid fortification. Baseline data on folate and vitamin B(12) status are necessary before mandatory flour fortification is implemented.

OBJECTIVES

To assess dietary intake of folate and vitamin B(12) and to determine blood concentrations of folate, vitamin B(12) and homocysteine in women of childbearing age as baseline data regarding folic acid fortification in Iran.

METHODS

A descriptive cross-sectional survey was performed with 579 healthy women as a representative sample of the Golestan province. Fasting blood samples were taken and dietary (24-hour recall), health and sociodemographic data were collected with an interview. Serum concentrations of folate and vitamin B(12) were measured with radioimmunoassay, and plasma homocysteine concentrations were assessed by high-performance liquid chromatography with fluorescence detection.

RESULTS

Mean serum concentrations of folate and vitamin B(12) were 13.6 nmol/l (95% CI 12.8-14.4) and 194.4 pmol/l (95% CI 183.8-205.0), respectively. Inadequate serum folate levels were present in 14.3% of the women and 22.7% had serum vitamin B(12) levels below normal. Mean plasma homocysteine concentration was 12.6 micromol/l (95% CI 12.1-13.2) and hyperhomocysteinemia was observed in 38.3% of the women. Mean daily intake of folate and vitamin B(12) was 198.3 microg (95% CI 185.4-211.3) and 2.6 microg (95% CI 1.9-3.2), respectively. Folate intake from food was positively correlated with serum folate concentrations (r = 0.084, p < 0.05) and inversely correlated with plasma homocysteine concentrations (r = -0.115, p < 0.01).

CONCLUSIONS

An insufficient vitamin B(12) as well as folate status is present in Iranian women of childbearing age. The final evaluation will be carried out 18 months after flour fortification and the results will be compared with baseline data obtained from the present study in order to show the efficacy and safety of folic acid fortification in Iran.

Early mortality predictors in coronary artery bypass grafting patients required intra-aortic balloon pump in perioperative and postoperative periods

AIM

The intra-aortic balloon pump (IABP) is commonly used for decreasing myocardial oxygen demand by systolic unloading in perioperative heart failure. The aim of this study was to determine perioperative prognostic factors for in-hospital mortality in coronary artery bypass grafting patients who received the intraaortic balloon pump.

METHODS

A total of 271 patients who underwent coronary artery bypass grafting and received intra-aortic balloon pump perioperatively between January 2002 and September 2006 were studied. The preoperative, operative and postoperative risk factors for early death were evaluated.

RESULTS

Early mortality rate in the study population was 17.3%. From variables entered into multivariate logistic regression the following parameters were identified as prognostic factors for early death: left main disease, diabetes, postoperative renal failure and cardiac arrest (P<0.05). The minor and major intra-aortic balloon pump related complications were not significant in univariate and multivariate analysis and its rate was 3.6%.

CONCLUSION

According to our study the mortality of IABP group is low compared to other studies, as well as IABP-associated complications. Also it revealed that there is no correlation between IABP-associated complications and early mortality.

The effect of gender on the pharmacokinetics of verapamil and norverapamil in human

The effects of gender on the pharmacokinetics of verapamil and its active metabolite, norverapamil, following single oral dose (80 mg, Isoptin) to 12 healthy male (mean age: 25.75+/-2.42 years, mean body weight: 70.59+/-9.94 kg) and 12 healthy female subjects (mean age: 24.08+/-2.84 years, mean body weight: 56.67+/-5.23 kg) were investigated in the present study. Plasma concentrations of verapamil and norverapamil were analysed using a modified high-pressure liquid chromatography method. Pharmacokinetic parameters were calculated by non-compartmental analysis for each subject. For verapamil the half-life (t1/2) and mean residence time (MRT) were significantly shorter in women than men (p<0.01 and p<0.05, respectively). For other pharmacokinetic parameters of verapamil there were no significant differences between males and females. For norverapamil, t1/2, MRT and time to reach to the maximum plasma concentration (Tmax) showed statistically significant differences between the two genders. The AUC(0-24) and AUC(0-infinity) ratios of norverapamil to verapamil were also calculated. The ratios were significantly higher in women compared with men. These observations indicate that the elimination rate of verapamil is faster in women than men which may be attributed to the higher activity of CYP3A4 or lower activity of P-glycoprotein in women compared with men. A contribution of both factors in the appearance of gender differences in verapamil pharmacokinetics is also possible.

Adrenal function in subgroups of the PCO syndrome assessed by a long ACTH test

Fifteen patients with the polycystic ovarian (PCO) syndrome were classified into Group A (n = 6) and Group B (n = 9) based on their LH responses to LHRH before and at 44 and 92h after administration of oestradiol benzoate. Adrenal function in both groups was assessed by comparing the hormone responses to ACTH (0.5mg twice daily for 4 days) with those obtained in nine normally ovulating women during the early follicular phase of their cycles. In Group A patients there was no significant difference from normals in the serum concentration of dehydroepiandrosterone sulphate (DHAS), 17 alpha-hydroxy-progesterone (17-OHP) or androgens (testosterone and dihydrotestosterone). In contrast, the serum concentrations in Group B were significantly higher (P less than 0.01) for each of these steroids before ACTH, and remained higher at 2 and 4 days for DHAS, but not for the other two steroids. The concentration of oestrone was significantly higher (P less than 0.05) in Group B patients before, and 2 days after, ACTH, while in Group A patients higher concentrations (P less than 0.02) were found only after 2 days. The concentrations of oestradiol, on the other hand, were not different from normal in either group before ACTH and became lower than normal in both groups at 2 days and remained lower at 4 days in Group B. The concentration of cortisol was within the normal range throughout in Group A, but was lower than normal after 4 days in Group B patients (P less than 0.05). The ratios between the sums of concentrations of DHAS to cortisol on days 2 and 4 (P less than 0.001) or 17-OHP to cortisol (P less than 0.05) were elevated in Group B compared with normal subjects. LH, FSH and prolactin values were normal throughout in Group A, but in Group B patients the mean value for LH was significantly elevated before ACTH and at 4 days after ACTH (P less than 0.02).