Myopathic manifestations across the adult lifespan of patients with malignant hyperthermia susceptibility: a narrative review.

Malignant hyperthermia susceptibility (MHS) designates individuals at risk of developing a hypermetabolic reaction triggered by halogenated anaesthetics or the depolarising neuromuscular blocking agent suxamethonium. Over the past few decades, beyond the operating theatre, myopathic manifestations impacting daily life are increasingly recognised as a prevalent phenomenon in MHS patients. At the request of the European Malignant Hyperthermia Group, we reviewed the literature and gathered the opinion of experts to define MHS-related myopathy as a distinct phenotype expressed across the adult lifespan of MHS patients unrelated to anaesthetic exposure; this serves to raise awareness about non-anaesthetic manifestations, potential therapies, and management of MHS-related myopathy. We focused on the clinical presentation, biochemical and histopathological findings, and the impact on patient well-being. The spectrum of symptoms of MHS-related myopathy encompasses muscle cramps, stiffness, myalgias, rhabdomyolysis, and weakness, with a wide age range of onset mainly during adulthood. Histopathological analysis can reveal nonspecific abnormalities suggestive of RYR1 involvement, while metabolic profiling reflects altered energy metabolism in MHS muscle. Myopathic manifestations can significantly impact patient quality of life and lead to functional limitations and socio-economic burden. While currently available therapies can provide symptomatic relief, there is a need for further research into targeted treatments addressing the underlying pathophysiology. Counselling early after establishing the MHS diagnosis, followed by multidisciplinary management involving various medical specialties, is crucial to optimise patient care.

Do patients dialysing with higher ultrafiltration rates report more intradialytic symptoms and longer postdialysis recovery times?

BACKGROUND: Many hemodialysis (HD) patients report intradialytic symptoms, and take time to recover postdialysis. To improve quality of life, patient groups have highlighted the need to reduce postdialysis fatigue and other peridialytic symptoms. As compartmental shifts of fluid during dialysis have been proposed to cause peridialytic symptoms we investigated whether patients dialysing with higher ultrafiltration rates (UFR) reported more intradialytic symptoms and recovery times. METHODS: We reviewed the hospital records of HD patients who completed a self-reported intradialytic symptom questionnaire, using a visual analogue scale, who had contemporaneous midweek pre- and postdialysis segmental bioimpedance measurements. RESULTS: Six hundred and five patients returned the peridialytic symptom questionnaire with pre- and postdialysis bioimpedance measurements. The majority were male (64.8%), mean age 64.2 ± 15.6 years, duration of dialysis treatment 26.8 (10.7-59.2) months, 85% treated by hemodiafiltration and mean dialysate temperature 35.4 ± 0.4°C. We divided patients into terciles according to UFR adjusted for weight, and there was a greater fall in the ratio of extracellular water (ECW) to total body water (TBW) postdialysis in the nonfistula arm from the lower to middle to higher tercile (0.8 (0-1.54) vs. 1.28 (0.52-1.85) vs. 1.54 (0.78-2.52)), trunk (1.5 (0.74-2.27) vs. 1.53 (0.99-2.2) vs. 1.98 (1.18-2.66)), left leg (1.56 (0.49-2.25) vs. 1.77 (1.24-2.43) vs. 2.08 (1.18-2.95)), lower versus higher tercile p < 0.05. However, no differences in intradialytic symptoms or postdialysis recovery times between the UFR terciles were observed. CONCLUSION: There were no differences in self-reported intradialytic symptoms or postdialysis recovery times with differing UFRs, despite changes in intracompartmental fluid shifts as measured by changes in ECW/TBW.

Exploring the Therapeutic Efficacy of Parsley (Petroselinum crispum Mill.) as a Functional Food: Implications in Immunological Tolerability, Reduction of Muscle Cramps, and Treatment of Dermatitis.

The status of parsley as a well-known folk medicine noted for its nutritional and medicinal properties prompted the exploration of its potential as a functional food and natural remedy. The paper aims to investigate the potential of parsley to enhance muscle function and alleviate psoriasiform dermatitis, eventually establishing it as a natural, well-tolerated alternative with specific benefits for both muscles and skin. This study examines the tolerability of parsley in a cohort of 937 participants by assessing immunoglobulin G (IgG) reactions. The findings reveal high tolerability, as 96.26% of participants experienced no adverse effects. Among the 902 individuals lacking hypersensitivity, 37.02% reported muscle cramps, with a notable 15.02% reduction observed in the subgroup consuming parsley juice. In the subset of 32 subjects with dermatitis, the application of parsley extract ointment led to a significant decrease in dermatological parameters (redness, thickness, scaling). While the control group exhibited improvements, statistical significance was not observed. Notably, four categories of affected area reduction were identified, with scaling demonstrating the most pronounced impact. The results propose that parsley holds promise for favorable tolerability, contributing to the alleviation of muscle cramps and presenting an effective alternative in dermatitis treatment. Nonetheless, sustained validation through long-term studies is imperative to substantiate these preliminary findings.

Structural and functional analysis of retinal vasculature in HANAC syndrome with a novel intronic COL4A1 mutation.

PURPOSE: Mutations of the COL4A1 gene, a major structural protein of vessels, may cause hereditary angiopathy with nephropathy, aneurysms and muscle cramps (HANAC) syndrome. The vascular structure and function of patients with HANAC is poorly known. Here, we report a family with HANAC syndrome associated to a previously unreported mutation in COL4A1. The structure and function of retinal vessels were detailed by adaptive optics ophthalmoscopy (AOO) and optical coherence tomography (OCT) angiography. METHODS: Clinical data from six affected individuals (43 to 72 years old) from a single family comprising two generations were collected. Imaging charts including conventional fundus imaging, OCT-angiography and AOO in static and dynamic (flicker) mode were reviewed. DNA sequencing was done in the proband. RESULTS: DNA sequencing of the proband revealed a heterozygous deletion of COL4A1 (NM_001845) at position 1120 in the intron 20 resulting in the loss of splicing donor site for exon 20 (c.1120 + 2_1120 + 8del heterozygote). Four patients had arterial hypertension, and three had kidney dysfunction, one of which under dialysis. By fundus examination, five had typical retinal arteriolar tortuosity with arteriolar loops. Wall-to-lumen ratio of arteries was within normal limits, that is, lower than expected for hypertensive patients. Several foci of arteriolar irregularities were noted in the two oldest patients. In three affected subjects, evaluation of the neurovascular coupling showed a higher flicker-induced vasodilation than a control population (6 % to 11 %; n < 5 %). CONCLUSIONS: Structural and dynamic analysis of retinal vessels in a HANAC family bearing a previously unreported intronic COL4 mutation was done. In addition to arteriolar tortuosity, we found reduced wall-to-lumen ratio, arteriolar irregularity and increased vasodilatory response to flicker light. These abnormalities were more marked in the oldest subjects. This abnormal flicker response affected also non-tortuous arteries, suggesting that microvascular dysfunction extends beyond tortuosity. Such explorations may help to better vascular dysfunction related to HANAC and hence better understand the mechanisms of end-organ damage.

Patient-Reported Prevalence, Characteristics, and Impact of Leg Cramps in an Urban Primary Care Clinic.

This study addresses the prevalence and characteristics of leg cramps in 294 primary care patients (mean age = 46.5 years), with 51.7% reporting leg cramps. Patients who experience resting or exercise-induced leg cramps were more likely to be older and female. Cramp severity averaged 5.6 on a scale of 1-10 and disturbed sleep "sometimes" or "often" in 55% of patients. Most patients did not discuss cramps with their clinician. Our study reveals a possible shift in patients who experience leg cramps to younger age and chronicity. Resting leg cramps should be reviewed by clinicians as a symptom of declining health and advancing aging.

Association between depression and dysmenorrhea among adolescent girls: multiple mediating effects of binge eating and sleep quality.

BACKGROUND: Dysmenorrhea has a significant negative impact on teenagers' quality of life, and its prevalence is increasing annually. Although studies have explored the factors affecting dysmenorrhea, it remains unclear how these factors interact with one another. This study aimed to explore the mediating role of binge eating and sleep quality between depression and dysmenorrhea. METHODS: This cross-sectional study recruited adolescent girls from the Health Status Survey of adolescents in Jinan, Shandong Province, and used multistage stratified cluster random sampling. Data was collected using an electronic questionnaire between March 9, 2022, and June 20, 2022. The Numerical Rating Scale and Cox Menstrual Symptom Scale were used to assess dysmenorrhea and the Patient Health Questionnaire-9 to assess depression. The mediation model was tested by Mplus 8.0, and the mediating effect was analyzed using the Product of Coefficients approach and the Bootstrap method. RESULTS: Among the total of 7818 adolescent girls included in this study, the prevalence of dysmenorrhea is 60.5%. A significant positive association was found between dysmenorrhea and depression. Binge eating and sleep quality seemingly mediate this association. The mediating effect of sleep quality (21.31%) was greater than that of binge eating (6.18%). CONCLUSIONS: The findings of this study point in the right direction for preventing and treating dysmenorrhea in adolescents. For adolescent dysmenorrhea, mental health should be considered and proactive steps taken for educating adolescents on healthy lifestyles to reduce negative consequences of dysmenorrhea. Longitudinal studies on the causal link and influence mechanisms between depression and dysmenorrhea should be conducted in the future.

Muscle Cramps in Outpatients with Liver Diseases in Tokyo, Japan.

Background and Objectives: Muscle cramps are often observed in patients with liver diseases, especially advanced liver fibrosis. The exact prevalence of muscle cramps in outpatients with liver diseases in Japan is unknown. Patients and Methods: This study examined the prevalence of, and therapies for, muscle cramps in outpatients with liver diseases in Tokyo, Japan. A total of 238 outpatients with liver diseases were retrospectively examined. We investigated whether they had muscle cramps using a visual analog scale (VAS) (from 0, none, to 10, strongest), and also investigated their therapies. Results: Muscle cramps were observed in 34 outpatients with liver diseases (14.3%); their mean VAS score was 5.53. A multivariate analysis demonstrated that older age (equal to or older than 66 years) was the only significant factor as-sociated with muscle cramps. The prevalence of muscle cramps among patients with liver diseases seemed not to be higher. The problem was that only 11 (32.4%) of 34 outpatients received therapy for their muscle cramps. Conclusions: Only age is related to muscle cramps, which is rather weak, and it is possible that this common symptom may not be limited to liver disease patients.

Open-label pilot study of ranolazine for cramps in amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: Neuronal hyperexcitability (manifested by cramps) plays a pathological role in amyotrophic lateral sclerosis (ALS), and drugs affecting it may help symptomatic management and slow disease progression. We aimed to determine safety and tolerability of two doses of ranolazine in patients with ALS and evaluate for preliminary evidence of drug-target engagement by assessing muscle cramp characteristics. METHODS: We performed an open-label dose-ascending study of ranolazine in 14 individuals with ALS in two sequential cohorts: 500 mg (cohort 1) and 1000 mg (cohort 2) orally twice daily. Each had a 2-week run-in period, 4-week drug administration, and 6-week safety follow-up. Primary outcome was safety and tolerability. Exploratory measures included cramp frequency and severity, fasciculation frequency, cramp potential duration, ALS Functional Rating Scale---Revised score, and forced vital capacity. RESULTS: Six and eight participants were enrolled in cohorts 1 and 2, respectively. There were no serious adverse events. Two subjects in cohort 2 discontinued the drug due to constipation. The most frequent drug-related adverse event was gastrointestinal (40%). Cramp frequency decreased by 54.8% (95% confidence interval [CI], 39%-70.8%) and severity decreased by 46.3% (95% CI, 29.5-63.3%), which appeared to be dose-dependent, with decreased awakening due to cramps. Other outcomes showed no change. DISCUSSION: Ranolazine was well tolerated in ALS up to 2000 mg/day, with gastrointestinal side effects being the most frequent. Ranolazine reduced cramp frequency and severity, supporting its investigation for muscle cramps in a future placebo-controlled trial.

Which physical activity in patients affected by hypoparathyroidism? A review of the literature and practical recommendations.

BACKGROUND: Hypoparathyroidism (HypoP) is a rare endocrine condition characterized by hypocalcaemia and hyperphosphatemia, as a consequence of absent or improperly low parathyroid hormone (PTH) levels. Patients affected by HypoP have a clinical condition often characterized by paresthesias and muscle spasms, as well as long-term consequences as nephrolithiasis, extraskeletal calcification, and fractures. In the literature, likely due to these symptoms, few data exist regarding the appropriate physical activity (PA) in subjects suffering from HypoP. PURPOSE: This review evaluates the literature on exercise-based approaches to the management of individuals affected by HypoP and evaluates: (1) the effects of physical exercise on muscle cramps and other clinical symptoms; (2) the effects of exercise on PTH and calcium level; (3) the most suitable clinical exercise testing; and (4) the most suitable exercise combination. METHODS AND RESULTS: A systematic search was conducted using the databases MEDLINE, Google Scholar using "hypoparathyroidism AND Physical Activity", "Training AND hypoparathyroidism", "Exercise AND muscle cramps", "Exercise AND Fatigue" as keywords. In addition, references list from the included articles were searched and cross-checked to identify any further potentially eligible studies. A total of 50 manuscripts were found among which 39 manuscripts were selected. A few clinical studies have been performed in HypoP patients to evaluate PA training protocols. CONCLUSION: Although further research is needed to draw solid conclusions regarding best PA protocols in subjects affected by HypoP, a PA protocol has been proposed within the manuscript to encourage patients to attempt exercise to improve their clinical conditions and their quality of life.

Health-related quality of life associated with nocturnal leg cramps in primary care: a mixed methods study.

BACKGROUND: Although nocturnal leg cramps are common, little research is available about their impact on quality of life. This mixed-methods study explored the impact of nocturnal leg cramps on health-related quality of life (HRQoL). METHODS: The study included primary care patients (>50 years) who reported suffering from nocturnal leg cramps (2016-2017). In the quantitative phase, patients completed a questionnaire about their HRQoL (SF-36) and the frequency of their cramps, and we computed the SF-36 scores. Then, we conducted a qualitative study using semi-structured interviews with patients with various levels of HRQol to explore their perception of the impact of cramps on their lives. RESULTS: A total of 114 patients (49%) agreed to participate in the quantitative study (mean age: 71, women: 62%) and 15 patients were included in the qualitative study (mean age: 69, women: 67%). The number of cramps in the previous week was low (mean: 1.6 (SD 1.5)). The SF-36 mean physical and mental summary scores were 43 and 50, respectively, and the domain scores were similar to a comparative general population. Whilst some patients reported little interference with their daily lives, others reported a major decrease in their HRQoL. SF-36 scores were not sufficient to describe the cramp-related impairment, as patients from all levels of SF-36 scores reported major impacts of NLC in the interviews. CONCLUSIONS: Some patients describe a specific impact of cramps on their lives, regardless of their HRQoL. These patients should be the target of future intervention trials.

Benefit of an Internet-Based Management System among Hemodialysis Patients at the Risk of Intradialytic Hypotension and Muscle Cramps: A Controlled before and after Study.

BACKGROUND: The purpose of this study was to observe the impact of an internet-based management system on the incidence of intradialytic hypotension (IDH) and muscle cramps in hemodialysis patients. METHODS: The patients, who underwent maintenance hemodialysis in the center from January 2018 to June 2020, were recruited and divided into the pre-intervention group (before operation of the internet-based hemodialysis management system, from January 2018 to December 2018) and intervention group (after operation of the system, from June 2019 to June 2020). The clinical outcomes were compared between groups. RESULTS: The compound endpoint of >1 IDH or muscle cramps happened in 182 patients (61.7%) in the pre-intervention group and 99 participants (30.8%) in the intervention group (relative risk [RR] = 0.50 [95% confidence interval [CI], 0.42; 0.60]). IDH occurred in 122 patients (1-5 episodes in 47 patients, 6-10 episodes in 25 patients, and >10 episodes in 50 patients) and 33 patients (30 patients had 1-5 episodes and 3 patients had 6-10 episodes) before and after execution of the internet-based management system, respectively (RR = 0.25 [95% CI, 0.18; 0.35]). The incidence of muscle cramps was significantly decreased (RR = 0.57 [95% CI, 0.45; 0.73]) after the implementation of the system, and the number of patients with 6-10 episodes dropped from 10 to 1. Multivariate analyses also showed significantly lower RRs in the intervention group: 0.29 ([95% CI, 0.20; 0.41]) for IDH and 0.58 ([95% CI, 0.45; 0.74]) for muscle cramps. Compared with the pre-intervention, participants in the intervention group had a large improvement in self-management (p < 0.001) and self-efficacy (p < 0.001). CONCLUSION: The study found that the internet-based hemodialysis management system was effective in reducing the IDH and muscle cramp events and improving self-management. It provided a significant implication for the development and application of internet-based programs in hemodialysis management.

[Neurological aspects of systemic lupus erythematosus in individuals with late ontogenetic debut.]

The review presents an analysis of publications on the features of the manifestation of systemic lupus erythematosus in the elderly. The article reflects the probable causes and mechanisms of the development of neurological manifestations of the disease. The clinical picture in elderly patients is described in detail, the features of immunological indicators are noted. This article discusses various variants of lesions of the nervous system in systemic lupus erythematosus, which differ in a wide range of clinical manifestations. Neuropsychic disorders of systemic lupus erythematosus are among the least studied aspects, and can be both a manifestation of the underlying disease, including those coinciding with the processes of immunosuppression, and undesirable phenomena against the background of ongoing treatment. At the same time, knowledge of the features of neurological manifestations in SLE with a debut in late ontogenesis in comparison with the data of laboratory and instrumental examination methods allows for early diagnosis and timely prescribing adequate therapy to elderly patients.

[Methimazole Tablets-Induced Algospasm: Two Cases Report].

Here, we reported two cases with hyperthyroidism who complained of myalgia and muscle cramps during treatment with methimazole tablets (or Thyrozol, the brand name). One case experienced muscle cramps after taking Thyrozol for 6 months, and by this time the patient's thyroid function had returned to normal. In the other case, pain caused by muscular cramps began after the patient took Thyrozol for two weeks and the patient's thyroid function had not returned to normal yet at the time. In both cases, pain caused by muscle cramps appeared while the patients were taking Thyrozol. The myalgia persisted in spite of a reduction in the Thyrozol dose, but was significantly relieved with the discontinuation of Thyrozol. Myalgia and muscle cramps did not recur after the patients were switched to methimazole ointment. There was a strong temporal association between oral administration of Thyrozol and pain caused by muscle cramps, which may indicate that myalgia and muscle cramps are adverse reactions of Thyrozol. Looking into the relevant literature on the topic, we explored in this report the possible mechanisms of the onset of muscle cramps associated with Thyrozol, and compared the adverse reactions of two different formulations of methimazole, intending to provide more clinical experience for the treatment of hyperthyroidism and the management of rare adverse reactions related to antithyroid drugs.

Correlates of night-time and exercise-associated lower limb cramps in healthy adults.

INTRODUCTION/AIMS: We explored correlates of night-time and exercise-associated lower limb cramps in participants of the 1000 Norms Project. METHODS: A volunteer community sample of healthy people aged ≥18 y underwent assessment of motor function and physical performance, and were questioned about muscle cramps in the previous 3 mo. RESULTS: Of 491 (221 female) participants age 18-101 y (mean: 59.12; SD: 18.03), about 1 in 3 experienced night-time lower limb cramps, and about 1 in 4 experienced exercise-associated lower limb cramps. For night-cramps, a one unit increase in Beighton score (greater whole-body flexibility) was associated with a 31% reduced odds of cramps (odds ratio [OR] = 0.69, 95% confidence interval [CI]:0.45, 0.99) and passing all three lesser-toe strength tests was associated with 50% reduced odds of cramps (OR = 0.50, 95% CI: 0.32, 0.78). For exercise-associated cramps, participants in the fourth (lowest arch) quartile of Foot Posture Index were 2.1 times (95% CI: 1.11, 3.95) more likely to experience cramps than participants in the first (highest arch) quartile. Odds of experiencing both types of cramps versus no cramps were lower with passing all three lesser-toe strength tests (OR = 0.40, 95% CI: 0.19, 0.85) and better performance in the six-minute walk test (OR = 0.997, 95% CI: 0.996, 0.998). DISCUSSION: People who experienced both exercise-associated and night-time cramps were less functional. The association between night-time cramps with less whole-body flexibility and reduced lesser-toe flexor strength should be explored to determine causation. Planovalgus (low-arched) foot type was independently associated with exercise-associated cramps. The effectiveness of foot orthoses for secondary prevention of exercise-associated cramps in people with low-arched feet should be explored.

Benign fasciculations: A follow-up study with electrophysiological studies.

INTRODUCTION/AIMS: Fasciculations can be symptomatic, yet not progress to amyotrophic lateral sclerosis (ALS), a condition categorized as benign fasciculation syndrome (BFS). We aimed to assess electrodiagnostic changes and clinical course over time in patients with BFS. METHODS: This was a retrospective review of medical records of patients who were referred because of a suspicion of ALS or who had directly asked for a consultation because of a personal concern regarding ALS. All clinical and electromyography (EMG) investigations were performed by the same neurologist, following an established protocol. In addition, laboratory testing and imaging studies were performed as determined to be clinically necessary. RESULTS: We included 37 subjects (mean age 46 ± 14.7 y, 29 male, 7 healthcare professionals). Most patients had experienced fasciculations in both upper and lower limb muscles (62.2%); the remaining patients had fasciculations only in their lower limbs. EMG in seven subjects showed chronic neurogenic potentials in addition to fasciculation potentials; all of these were older men. Follow-up data were available in 24 patients (median 4.7 y), 21 with repeat EMGs, including all those with neurogenic EMG changes at baseline (median 6.5 y). Two-thirds of patients reported symptomatic improvement: 57.1% of those with abnormal EMG and 61.1% with normal EMG. The EMG changes were stable. DISCUSSION: Prognosis of BFS is favorable, regardless of minor EMG abnormalities. The latter do not necessarily imply progression to ALS.

A randomized, double-blind, placebo-controlled, multicenter study assessing the efficacy of magnesium oxide monohydrate in the treatment of nocturnal leg cramps.

BACKGROUND: Magnesium supplements are widely used for prophylaxis and treatment of nocturnal leg cramps (NLC). However, there is little evidence in support of their effectiveness. The main impediment stems from the lack of assessments of cellular absorption. In the current study, we tested the efficacy and safety of a magnesium supplement - magnesium oxide monohydrate (MOMH), for which increased cellular absorption rates were demonstrated in an ex-vivo setting. METHODS: A randomized, double-blind, placebo-controlled multicenter study was conducted in hospitals and outpatient clinics in Ukraine, from February to August 2018. Eligible subjects received a capsule with MOMH 226 mg or placebo, once daily, at bedtime, for a 60-day period. The assessed parameters included frequency and duration of NLC episodes, quality of sleep, NLC-induced pain and quality of life sub-scores. The Fisher's Exact Test for comparison of groups by categorical variables was used. The Student's test or Mann-Whitney test were used for between-group comparison at different timepoints. ANCOVA followed by contrast analysis was used for comparison of groups at the end of the study. RESULTS: 175 (81%) out of 216 initially screened subjects completed the study. The number of NLC episodes has significantly decreased by the end of the study period as compared to baseline in both groups (p < 0.001 for both). There was a significant between-group difference in the magnitude of reduction in NLC episodes (p = 0.01), indicating a higher decrease in the MOMH group as compared to the placebo group (- 3.4 vs - 2.6, respectively). In addition, MOMH treatment resulted in a greater reduction in NLC duration (p < 0.007) and greater improvement in sleep quality (p < 0.001) as compared to placebo. CONCLUSIONS: MOMH was shown to be effective in the treatment of NLC as well as safe and well-tolerated. TRIAL REGISTRATION: NCT03807219 , retrospectively registered on January 16, 2019.

Structural Refinement of Carbimazole by NMR Crystallography.

The characterization of the three-dimensional structure of solids is of major importance, especially in the pharmaceutical field. In the present work, NMR crystallography methods are applied with the aim to refine the crystal structure of carbimazole, an active pharmaceutical ingredient used for the treatment of hyperthyroidism and Grave's disease. Starting from previously reported X-ray diffraction data, two refined structures were obtained by geometry optimization methods. Experimental 1H and 13C isotropic chemical shift measured by the suitable 1H and 13C high-resolution solid state NMR techniques were compared with DFT-GIPAW calculated values, allowing the quality of the obtained structure to be experimentally checked. The refined structure was further validated through the analysis of 1H-1H and 1H-13C 2D NMR correlation experiments. The final structure differs from that previously obtained from X-ray diffraction data mostly for the position of hydrogen atoms.

Predictors of Intradialytic Symptoms: An Analysis of Data From the Hemodialysis Study.

BACKGROUND: Most patients receiving maintenance hemodialysis (HD) experience adverse symptoms, which are associated with decreased quality of life. Despite decades of experience, our understanding of causes of HD symptoms remains limited. We aimed to identify modifiable patient- and HD-related predictors of intradialytic symptoms. STUDY DESIGN: Prospective cohort. SETTING & PARTICIPANTS: We leveraged patient-level (n=1,838) and HD session-level (n=64,797) data from the Hemodialysis Trial. EXPOSURE: Pre-HD serum urea nitrogen (SUN) level, pre-HD systolic blood pressure (SBP), intradialytic SBP decline, and ultrafiltration rate (UFR). OUTCOMES: Intra-HD symptoms, including cramps, nausea, chest pain, headache, and lightheadedness. ANALYTICAL APPROACH: Random-effects logistic regression models. RESULTS: Overall, symptoms occurred in 10.7% of HD sessions. Higher pre-HD SUN level (per 10 mg/dL) was associated with higher adjusted odds of muscle cramping and lightheadedness (adjusted ORs [aORs] of 1.20 [95% CI, 1.17-1.22] and 1.13 [95% CI, 1.08-1.18], respectively). SBP decline (from the predialysis value to the dialysis session nadir, per each 10-mm Hg decrease) was associated with greater risk for muscle cramping, headache, chest pain, vomiting, and lightheadedness (the largest aORs were for the 2 latter symptoms: 1.24 [95% CI, 1.20-1.28] and 1.37 [95% CI, 1.33-1.42], respectively). Higher UFR (per 1 mL/kg/h) was associated with greater odds of cramping (aOR, 1.03; 95% CI, 1.02-1.03). Conversely, higher pre-HD SBP (per 10 mm Hg) was associated with reduced risk for vomiting (aOR, 0.88; 95% CI, 0.85-0.92) and lightheadedness (aOR, 0.82; 95% CI, 0.80-0.85). LIMITATIONS: Measured osmolality, dialysate prescription data, and time stamps for symptom occurrence were not available. Clinical trial data may not be broadly generalizable. CONCLUSIONS: Higher pre-HD SUN level, UFR, pre-HD SBP, and SBP decline are independently associated with different patterns of adverse intradialytic symptoms. Recognition that different symptoms may have variable causes may allow tailoring of personalized treatments in future interventional studies.

Effect of furosemide on muscle cramps in patients with liver cirrhosis.

BACKGROUND AND AIM: Patients with cirrhosis usually experience muscle cramps of varying severity. Although diuretics have been reported to cause muscle cramps, clinical evidence is limited. Also, it has been pointed out that the use of diuretics is associated with the progression of sarcopenia in patients with cirrhosis. We conducted a questionnaire survey to clarify the effects of diuretics and skeletal muscle loss on muscle cramps. METHODS: Overall, we enrolled 152 adults with cirrhosis in this study. Cramp questionnaires were obtained after informed consent. Study variables (demographics, physical findings, serum metabolic panel, and drugs taken that affect muscle cramps) were extracted from medical records. Body composition, including muscle volume, was analyzed using a bioelectrical impedance analysis method, and muscle strength (handgrip) was evaluated at enrollment. Cross-sectional skeletal muscle area was evaluated on computed tomography imaging at the L3 vertebral level to investigate the relationship between muscle cramps and sarcopenia. RESULTS: The proportion of furosemide administration was higher in patients with cramping compared with those without. On a multivariate logistic regression analysis, furosemide use was a significant factor in the presence of muscle cramps. Furthermore, regarding factors contributing to muscle cramp severity, furosemide use was extracted by multivariate logistic regression analysis. In the presence or severity of muscle cramps, skeletal muscles did not show any significant difference. CONCLUSIONS: Furosemide use for patients with cirrhosis was considered a risk factor for occurrence and severity of muscle cramps. On the other hand, skeletal muscle mass loss was not associated with muscle cramps.

Quinine exposure and the risk of acute kidney injury: a population-based observational study of older people.

OBJECTIVES: to establish and quantify any observable association between the exposure to community prescriptions for quinine and acute kidney injury (AKI) events in a population of older adults. DESIGN: two observational studies using the same dataset, a retrospective longitudinal cohort study and a self-controlled case series (SCCS). SETTING: NHS health board in Scotland. PARTICIPANTS: older adults (60+ years) who received quinine prescriptions in Tayside, Scotland, between January 2004 and December 2015. The first study included 12,744 individuals. The SCCS cohort included 5,907 people with quinine exposure and more than or equal to one AKI event. MAIN OUTCOME MEASURED: in the first study, multivariable logistic regression was used to calculate odds ratios (ORs) for AKI comparing between episodes with and without recent quinine exposure after adjustment for demographics, comorbidities and concomitant medications. The SCCS study divided follow-up for each individual into periods 'on' and 'off' quinine, calculating incidence rate ratios (IRRs) for AKI adjusting for age. RESULTS: during the study period, 273,596 prescriptions for quinine were dispensed in Tayside. A total of 13,616 AKI events occurred during follow-up (crude incidence 12.5 per 100 person-years). In the first study, exposure to quinine before an episode of care was significantly associated with an increased probability of AKI (adjusted OR = 1.27, 95% confidence interval (CI) 1.21-1.33). In the SCCS study, exposure to quinine was associated with an increased relative incidence of AKI compared to unexposed periods (IRR = 1.20, 95% CI 1.15-1.26), with the greatest risk observed within 30 days following quinine initiation (IRR = 1.48, 95% CI 1.35-1.61). CONCLUSION: community prescriptions for quinine in an older adult population are associated with an increased risk of AKI.