Examining the relationship between sleep quality and depressive symptoms in Korean women engaged in soccer during the coronavirus pandemic.

Introduction: The COVID-19 pandemic has caused sudden changes to daily lives, such as self-isolation and social distancing, and has negatively affected sleep quality and patterns. The resulting psychological discomfort has caused many Korean women to experience depressive moods. Vigorous physical activity is considered effective in improving sleep quality and alleviating depressive symptoms. As a form of vigorous physical activity, soccer could be used to improve women's mental health. This study aimed to ascertain the effects of playing soccer on sleep quality and depressive symptoms in women. Methods: Non-face-to-face questionnaires were administered using Pittsburgh Sleep Quality Index to measure sleep quality and Patient Health Questionnaire-9 to measure depressive symptoms, targeting 200 of 297 soccer-playing Korean women aged 20-50 years, from October 13, 2022, to January 15, 2023. A total of 172 questionnaires administered to soccer participants were used, while 28 with insincere and double or no-responses were excluded. Additionally, 124 samples of non-exercise participants were collected, with the help of "EMBRAIN," a Korean research and survey company. This study analyzed differences in sleep quality and depressive symptoms, and correlations and multiple regression analysis were performed. Results: The soccer group was shown to have a high quality of sleep. In relation to the effect of sleep quality on depressive symptoms, subjective sleep quality, sleep latency, sleep disturbance, use of sleeping pills, and daytime functional disorder had a significant effect. In the relation to the effect of sleep quality on depressive symptoms, significant effect was found in subjective sleep quality, sleep latency, sleep disturbance, and daytime functional disorder of soccer participants, and non-exercise participants displayed significant effect in subjective sleep quality, sleep disturbance, and the use of sleeping pills. Discussion: This study examined the effect of soccer participation on sleep quality and depressive symptoms among women. Soccer, which requires high activity and teamwork levels, improves sociability in women by enhancing their sense of belonging, self-confidence, and team spirit.

[Veronal, in Lord Edgware Dies: A Double-edged Sword of Sedation and Addiction].

Veronal, introduced during the early 20th century was widely used as a sleeping pill at the time, and this drug is mentioned in Agatha Christie's novels. Research has proved that in addition to their sedative effects, Veronal and other sleeping pills with similar mechanisms of action are associated with undesirable effects that can lead to addiction and overdose. Barbiturate-induced deaths include the high-profile suicides of the famous American actress Marilyn Monroe and Ryunosuke Akutagawa, a prolific Japanese writer and poet. Soseki Natsume attempted an overdose of sleeping pills; however, he was surrounded by many disciples, and a disciple who observed the adverse effects of the drug prevented Natsume from overdosing. This example highlights that addiction depends on the social relationships surrounding an individual.

Hypnotic prescription trends and patterns for the treatment of insomnia in Japan: analysis of a nationwide Japanese claims database.

BACKGROUND: There is limited consensus regarding the optimal treatment of insomnia. The recent introduction of orexin receptor antagonists (ORA) has increased the available treatment options. However, the prescribing patterns of hypnotics in Japan have not been comprehensively assessed. We performed analyses of a claims database to investigate the real-world use of hypnotics for treating insomnia in Japan. METHODS: Data were retrieved for outpatients (aged ≥ 20 to < 75 years old) prescribed ≥ 1 hypnotic for a diagnosis of insomnia between April 1st, 2009 and March 31st, 2020, with ≥ 12 months of continuous enrolment in the JMDC Claims Database. Patients were classified as new or long-term users of hypnotics. Long-term use was defined as prescription of the same mechanism of action (MOA) for ≥ 180 days. We analyzed the trends (2010-2019) and patterns (2018-2019) in hypnotics prescriptions. RESULTS: We analyzed data for 130,177 new and 91,215 long-term users (2010-2019). Most new users were prescribed one MOA per year (97.1%-97.9%). In 2010, GABAA-receptor agonists (benzodiazepines [BZD] or z-drugs) were prescribed to 94.0% of new users. Prescriptions for BZD declined from 54.8% of patients in 2010 to 30.5% in 2019, whereas z-drug prescriptions remained stable (~ 40%). Prescriptions for melatonin receptor agonist increased slightly (3.2% to 6.3%). Prescriptions for ORA increased over this time from 0% to 20.2%. Prescriptions for BZD alone among long-term users decreased steadily from 68.3% in 2010 to 49.7% in 2019. Prescriptions for ORA were lower among long-term users (0% in 2010, 4.3% in 2019) relative to new users. Using data from 2018-2019, multiple (≥ 2) MOAs were prescribed to a higher proportion of long-term (18.2%) than new (2.8%) users. The distribution of MOAs according to psychiatric comorbidities, segmented by age or sex, revealed higher proportions of BZD prescriptions in elderly (new and long-term users) and male (new users) patients in all comorbidity segments. CONCLUSION: Prescriptions for hypnotics among new and long-term users in Japan showed distinct patterns and trends. Further understanding of the treatment options for insomnia with accumulating evidence for the risk-benefit balance might be beneficial for physicians prescribing hypnotics in real-world settings.

Association of sleep duration and sleeping pill use with mortality and life expectancy: A cohort study of 484,916 adults.

OBJECTIVES: To compare mortality risk and life expectancy among individuals with different sleep durations and sleeping pill use. METHODS: A cohort of 484,916 community-dwelling adults in Taiwan was recruited into a health screening program from 1994 to 2011. Subjects were categorized by daily sleep duration into 4 groups: extremely short (<4 hours), short (4-6 hours), medium (6-8 hours), and long (>8 hours). Cox proportional hazards models were used to investigate the associations of mortality risk with sleep duration and sleeping pill use. Models were adjusted for sociodemographic characteristics, lifestyle, and comorbidities. Life expectancy tables were calculated among sleeping pill users and nonusers with different sleep durations. RESULTS: With 6- 8 hours of daily sleep, sleeping pill nonusers had the lowest mortality risk. Sleeping pill users, even with this optimal amount of sleep, had a 55% (p < .001, 95% CI, 1.38-1.73) higher mortality risk than nonusers. The life expectancy of 30-year-old male sleeping pill users with extremely short or long sleep durations was 12-13 years shorter than sleeping pill nonusers who had 6-8 hours of sleep. On average, life expectancy in individuals using sleeping pills (vs. nonusers) was shorter by 5.3 (95% CI, 4.10-6.32) years in men and 5.7 (95% CI, 5.28-7.98) years in women. CONCLUSIONS: This study suggests that the use of sleeping pills is associated with an increased risk of mortality and shortened life expectancy, especially in extreme sleepers. Regular users should be aware of potential harms from sleeping pills.

'It's like Taking a Sleeping Pill': Student Experience of Autonomous Sensory Meridian Response (ASMR) to Promote Health and Mental Wellbeing.

Autonomous Sensory Meridian Response (ASMR) is purposely elicited by some individuals to promote health and mental wellbeing. The aim of the current study was to explore how ASMR is used and its perceived benefits in a student population. We employed semi-structured qualitative interviews, with eight female students who self-reported as ASMR-sensitive users. Inductive thematic analysis, underpinned by a phenomenological framework, was applied to the data. Two themes, each with three subthemes, were identified; these highlighted the journey from first discovering ASMR to present experience and the use of ASMR to promote health and mental wellbeing both directly and indirectly. For some, ASMR was used daily, whilst for others it was used in a relapsing-remitting fashion: usage increased when struggling with mental wellbeing and was most often used as a tool to induce sleep or distraction when feeling anxious. Participants also reported ASMR-eliciting content as intriguing, and that the phenomenon was regarded as taboo. ASMR appears to play an important role in promoting health and mental wellbeing; frequency of use, preferred triggers, and purpose of use varied, highlighting its flexible and subjective nature. It provides a potential cost-effective tool in populations such as students where mental health needs are burgeoning.

Curcuminoids, a major turmeric component, have a sleep-enhancing effect by targeting the histamine H1 receptor.

Turmeric (Curcuma longa) had been considered as a universal panacea in functional foods and traditional medicines. In recent, the sedative-hypnotic effect of turmeric extract (TE) was reported. However, sleep-promoting compounds in TE have been not yet demonstrated. Curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) are the major constituents of turmeric being responsible for its various biological activities. Therefore, they can be first assumed to be sedative-hypnotic compounds of TE. In the present study, we aimed to investigate the effects and underlying mechanisms of curcuminoids and each constituent on the sleep-wake cycle of mice. Molecular docking studies, histamine H1 receptor (H1R) binding assays, and H1R knockout animal studies were used to investigate the molecular mechanisms underlying the sleep-promoting effects. Curcuminoids and their constituents reduced sleep latency and increased sleep duration in the pentobarbital-induced sleep test in mice. In addition, curcuminoids significantly increased the duration of NREMS and reduced sleep latency without altering the REMS and delta activity. Curcumin, demethoxycurcumin, and bisdemethoxycurcumin were predicted to interact with H1R in the molecular model. In the binding affinity assay, we found that curcuminoids, as well as their constituents, significantly bind to H1R with the Ki value of 1.49 µg mL-1. Furthermore, sleep latency was reduced and NREMS frequency was increased following curcuminoid administration in wild-type mice but not in H1R knockout mice. Therefore, we conclude that curcuminoids reduce sleep latency and enhance the quantity of NREMS by acting as modulators of H1R, indicating their usefulness in treating insomnia.

Stress, anxiety, and depression among students at the Faculty of Medicine of Sousse (Tunisia).

OBJECTIVE: To evaluate the frequency of anxious and depressive symptoms and to determine their associated factors in a population of students enrolled at the Faculty of Medicine of Sousse (Tunisia). METHODS: this is a descriptive cross-sectional study that took place at the Faculty of Medicine of Sousse over the period from 09/15/2017 to 03/15/2018. An anonymous questionnaire was administered to the students in the guided teaching rooms. The assessment of anxiety and depressive symptoms was based on the Anxiety and Depression Scale (HADS) and the quality of sleep was assessed by the PSQI questionnaire. RESULTS: A total of 202 medical students participated in the study. The average PSQI score was 5.62±2.87 and 47% of students had poor sleep quality (PSQI ≥ 6). Symptoms of anxiety and depression were observed in 73 (36.1%) and 45 (22.3%) students respectively. The mean HADS-A score was 9.21±4.17 and that of the HADS-D score was 7.37±4.06. In univariate analysis, the factors found to predict a high level of perceived stress were the study cycle (p=0.022) and poor quality of sleep (p 11) were the use of sleeping pills (p=0.004), the quality of sleep (p<0.001), and a high level of perceived stress (p<0.001). The high level of perceived stress was found to predict depression (p=0.006).In the multivariate analysis of variables in the present study, poor sleep quality was a factor independently related to high perceived stress in medical students (ORa=9.062 [4.247-19.334]) while being a medical student of the 1st cycle proved to be a protective factor (ORa=0.101 [0.025-0.406]). Use of sleeping pills (ORa=4.481 [1.135-17.682]), poor sleep quality (ORa=2.131 [1.081-4.203]) and high level of perceived stress (ORa=5.790 [2.444-13.716]) were factors independently related to anxiety symptoms. Female sex was a protective factor for depressive symptoms (ORa=0.440 [0.205-0.945]) while a high level of perceived stress was a factor independently related to depressive symptoms (ORa=3.429 [1.469-8.005]). HAD-A and HAD-D scores were correlated (r=0.631 ; p<0.001). CONCLUSION: sleep disturbances, perceived stress, anxious and depressive symptoms are common among Tunisian medical students. Prevention strategies targeting the improvement of sleep quality and student stress management should be developed at the faculty and ministerial level.

Risk factors and a nomogram model for postoperative delirium in elderly gastric cancer patients after laparoscopic gastrectomy.

BACKGROUND: To evaluate the risk factors of postoperative delirium (POD) in elderly gastric cancer (GC) patients after laparoscopic gastrectomy and construct a predictive model. METHODS: Elderly GC patients undergoing laparoscopic gastrectomy were enrolled and grouped based on the status of POD development within postoperative 7 days. Independent risk factors were selected out by univariate and multivariate logistic regression analyses and then enrolled in the nomogram prediction model. RESULTS: A total of 270 elderly GC patients were enrolled, and POD occurred in 74 (27.4%) patients within postoperative 7 days. The results of multivariate regression analysis indicated that age (OR: 3.30, 95% CI: 1.41-6.85, P < 0.001), sleeping pills (OR: 1.87, 95% CI: 1.12-3.09, P = 0.012), duration of ICU stay (OR: 1.55, 95% CI: 1.02-2.37, P = 0.029), albumin/fibrinogen ratio (AFR) (OR: 1.74, 95% CI: 1.03-2.76, P = 0.019), and neutrophils/lymphocytes ratio (NLR) (OR: 2.12, 95% CI: 1.11-4.01, P = 0.016) were five independent risk factors for POD in elderly GC patients. The AUC of the constructed nomogram model based on these five factors was 0.807. CONCLUSIONS: This study highlighted that age, AFR, NLR, sleeping pills taking, and duration of ICU stay were independent risk factors for POD, and the nomogram model based on these factors could effectively predict POD in elderly GC patients.

The effect of COVID-19 pandemic on sleep-related problems in adults and elderly citizens: An infodemiology study using relative search volume data.

COVID-19 has had a substantial national impact in South Korea, causing negative psychological responses including sleep-related problems. Literature indicates sleep problems among the general population have been reported to be as high as around 35.7% during the first 8 months of COVID-19. Therefore, the aim of this study was to investigate the impact of COVID-19 pandemic on sleep problems among the general population using relative search volume (RSV) data, and whether there are any differences by age and time periods spanning before and during the pandemic. RSV data was collected from the most commonly used search engine in South Korea, NAVER. Search terms were grouped into 4 categories: insomnia, other sleep disorders, sleeping pills, and sleeping pill side effects. Time points were divided into 4 periods, each 7 months long: 7 months before COVID-19 (T0), first confirmed COVID-19 case to 7 months after (T1), 7 to 14 months (T2), and 14 to 21 months (T3). A 2x4 factorial Analysis of Variance was conducted to investigate main effects and interactions between age and time periods. Main effects and interaction effects of age and time periods were significant for all search term groups. For all search terms, both age groups showed dramatic increase from T0 to T1. In age group 60 or above, RSV continued to increase for other sleep disorders and sleeping pill. Insomnia and sleeping pill side effects showed decreasing trend at T3. In general, sudden increase in RSV after occurrence of COVID-19 followed by slow decline were observed. However, for age group 60 or above, RSV values of other sleep disorders and sleeping pills continued to increase, suggesting slower recovery of psychological impact with increasing age. Overall, the results underscore the importance of implementing preventive measures for monitoring sleep problems during the pandemic, especially in the elderly.

Factors associated with sleep problems and sleeping pill use in Brazilians.

OBJECTIVE: To estimate the prevalence of sleep problems and sleeping pill use and associated factors in the Brazilian population. METHODS: This study was conducted with data from the 2019 Brazilian National Health Survey. Our sample consisted of 94,114 participants and the outcomes analyzed were sleep problems and sleeping pill use. Sociodemographic, lifestyle, and health characteristics were explored in a descriptive and multivariate analysis with Poisson regression, robust variance, and 5% significance. RESULTS: We found a 35.1% (95%CI: 34.5-35.7) and 8.5% (95%CI: 8.2-8.9) prevalence of sleep problems and sleeping pill use, respectively. Sleep problems were associated with women (PR = 1.41; 95%CI: 1.36-1.46), individuals who self-assess their health as regular/poor/very poor (PR = 1.56; 95%CI: 1.51-1.62), those with chronic diseases (PR = 1.70; 95%CI: 1.64-1.78), those who use alcohol excessively (PR = 1.14; 95%CI: 1.09-1.20), and smokers (PR = 1.16; 95%CI: 1.10-1.22). Sleeping pill use was associated with women (PR = 1.57; 95%CI: 1.43-1.73), divorcees (PR = 1.46; 95%CI: 1.30-1.65), urban denizens (PR = 1.32; 95%CI: 1.21-1.45) those who self-assess their health as regular/poor/very poor (PR = 1.79; 95%CI: 1.64-1.95), those with chronic diseases (PR = 4.07; 95%CI: 3.48-4.77), and smokers (PR = 1.49; IC95%: 1.33-1.67). CONCLUSION: This study found that the prevalence of sleep problems and sleeping pill use in Brazilians indicates the need for attention and sleep care for this population, especially in women and those with lifestyle and health conditions associated with the analyzed outcomes.

The prevalence and predictors of cardiovascular diseases in Kherameh cohort study: a population-based study on 10,663 people in southern Iran.

BACKGROUND: The prevalence of cardiovascular disease (CVD) is rapidly increasing in the world. The present study aimed to assess the prevalence and Predictors factors of CVD based on the data of Kherameh cohort study. METHODS: The present cross-sectional, analytical study was done based on the data of Kherameh cohort study, as a branch of the Prospective Epidemiological Studies in Iran (PERSIAN). The participants consisted of 10,663 people aged 40-70 years. CVD was defined as suffering from ischemic heart diseases including heart failure, angina, and myocardial infarction. Logistic regression was used to model and predict the factors related to CVD. Additionally, the age-standardized prevalence rate (ASPR) of CVD was determined using the standard Asian population. RESULTS: The ASPR of CVD was 10.39% in males (95% CI 10.2-10.6%) and 10.21% in females (95% CI 9.9-10.4%). The prevalence of CVD was higher among the individuals with high blood pressure (58.3%, p < 0.001) as well as among those who smoked (28.3%, p = 0.018), used opium (18.2%, p = 0.039), had high triglyceride levels (31.6%, p = 0.011), were overweight and obese (66.2%, p < 0.001), were unmarried (83.9%, p < 0.001), were illiterate (64.2%, p < 0.001), were unemployed (60.9%, p < 0.001), and suffered from diabetes mellitus (28.1%, p < 0.001). The results of multivariable logistic regression analysis showed that the odds of having CVD was 2.25 times higher among the individuals aged 50-60 years compared to those aged 40-50 years, 1.66 folds higher in opium users than in non-opium users, 1.37 times higher in smokers compared to non-smokers, 2.03 folds higher in regular users of sleeping pills than in non-consumers, and 4.02 times higher in hypertensive individuals than in normotensive ones. CONCLUSION: The prevalence of CVD was found to be relatively higher in Kherameh (southern Iran) compared to other places. Moreover, old age, obesity, taking sleeping pills, hypertension, drug use, and chronic obstructive pulmonary disease had the highest odds ratios of CVD.

Nationwide database analysis of insomnia, depression, and sleeping pill prescriptions in hepatocellular carcinoma patients.

OBJECTIVE: To clarify the status of insomnia and depression and the prescription of sleeping pills in hepatocellular carcinoma (HCC) patients before and after HCC diagnosis and treatment. METHODS: Patients' data from a Japanese health insurance claims database were analyzed retrospectively to determine the incidence of insomnia and depression and their association with sleeping pill prescriptions during the 6 months before and after HCC diagnosis and treatment. RESULTS: A total of 9,109 HCC patients (median age at diagnosis = 71.5 years, 68.1% male) were analyzed. The incidences of insomnia and depression increased significantly after HCC diagnosis. Insomnia was reported in 15.0% of patients before diagnosis, and it increased to 27.6% after diagnosis. Similarly, depression was reported in 6.3% and 11.3% before and after diagnosis, respectively. The incidences of insomnia and depression before diagnosis were higher in patients with concomitant liver diseases including hepatitis, cirrhosis, and hepatic encephalopathy. However, the rate of sleeping pill prescription was significantly lower in patients with concomitant liver diseases after diagnosis. The incidence of fracture was higher in insomnia or depression patients than others and in patients treated with sleeping pills than without before and after diagnosis. CONCLUSIONS: HCC patients had increased risks of insomnia and depression after diagnosis. The high risk of fracture in HCC patients with insomnia and depression and treated with sleeping pills suggests that it is difficult to optimize the management of HCC patients, especially those with concomitant liver diseases.

Suvorexant in the Treatment of Difficulty Falling and Staying Asleep (Insomnia).

Purpose of Review: Insomnia affects more than 10% of the population and causes significant discomfort and disability. Suvorexant is an orexin receptor antagonist that specifically targets the wake-sleep cycle. This review summarizes recent and seminal evidence in the biological and physiological evidence of insomnia, the mechanism of action of suvorexant in treating insomnia, and clinical evidence regarding its use. Recent Findings: There is no single clear diagnosis for insomnia, and thus prevalence is not entirely clear, but it is estimated to affect 10%-30% of the adult population. Comorbidities include obesity, diabetes, and various psychiatric conditions, and insomnia likely has a contributing role in these conditions. Insomnia, by definition, impacts sleep quality and also wakefulness, including academic success and work efficiency. Insomnia is likely related to genetic susceptibility and a triggering event, leading to hyper-arousal states and functional brain disturbances. This leads to hyperactivity of the hypothalamic-pituitary-adrenal axis, over-secretion of corticotropin-releasing factor, and aberrancy in neurotransmitter release. Though several pharmacological options exist for the treatment of insomnia, there is equivocal data regarding their efficacy or limits to their use due to side effects and contraindications. Suvorexant is a novel dual orexin receptor antagonist, which is shown to improve sleep by reducing arousals. Unlike classical therapeutics, suvorexant does not alter the sleep profile; it prolongs the time spent in each sleep state. Though it may cause some somnolence, it is milder than reported with other drugs. Summary: Multiple clinical studies support the use of suvorexant in insomnia. In primary insomnia, suvorexant is effective (over placebo), as measured by polysomnography and reported by patients, in both attaining and maintaining sleep. Similar, albeit to a smaller degree, results were found in secondary insomnia. Suvorexant carries two significant advantages over existing therapies; it has a much better safety profile in approved doses, and it preserves natural sleep architecture, thus promoting more restful sleep and recovery. Unfortunately, data exists mostly for suvorexant versus placebo, and head-to-head trials with common hypnotics are needed to assess the true efficacy of suvorexant over the alternatives. And while tolerance is less likely to develop, close monitoring of post-marketing data is required to evaluate for long term adverse events and efficacy.

Risk of obstructive sleep apnea among taxi-motorbike drivers in Parakou city in West Africa and associated factors with road traffic accidents.

OBJECTIVES: Obstructive sleep apnea (OSA) is an underdiagnosed chronic respiratory disease, causing excessive daytime sleepiness (EDS) and road traffic accidents (RTA). This study aimed to determine the risk of OSA among taxi-motorbike drivers (TMD) and factors associated with RTA in Parakou, Benin. METHODS: A cross-sectional comparative study was carried out between July and September 2020, including 225 TMD and 450 motorbike drivers other than TMD (non-TMD). A multiple logistic regression was then performed to determine factors associated with RTA. RESULTS: The mean age of participants was 38.2 ± 10.2 and 36.6 ±10.9 years, respectively, for TMD and non-TMD (p = .048). The average daily working time was 10.7 ± 2.3H and 9.1±3.5H, respectively, for TMD and non-TMD (p < .001). Average sleeping time was comparable in both groups (7.5±1.4H vs 7.4±1.4H; p = .415). TMD significantly more complained of non-restorative sleep (38.7% vs 18.4%; p < .001) but less of EDS (20.0% vs 28.7%; p = .015). Abdominal obesity predominated in TMD (13.8% vs 4.4%; p < .001). An increased risk of OSA (NoSAS score ≥8) was diagnosed in 25.8% TMD and 26.7% non-TMD (p = .805). Overall, 25.8% of TMD and 18.4% of non-TMD (p = .027) reported at least one RTA in the last 12 months. After adjusted analysis, the unique factor associated with RTA was a daily sleeping pills consumption (aOR=2.2; 95%CI = 1.2-3.8; p = .006). CONCLUSION: There is need to improve systematic screening and diagnosis of OSA in both TMD and non-TMD and reinforce the regulation and consumption of sleeping pills.

Direct multiclass desorption electrospray ionization-tandem mass spectrometry method for the analysis of sleep inducers and ototoxic drugs in dried blood spots.

RATIONALE: An unconventional and innovative approach for the quantitative determination of 11 ototoxic and narcoleptic drugs in whole blood is described. The multiclass method allows the inclusion of the most widespread drugs on the market (antihistamines, antidepressants, antihypertensives, anxiolytics, opioids, Z-drugs) responsible for 10% of occupational accidents. METHODS: The developed procedure involved the use of the desorption electrospray ionization (DESI) interface for the direct analysis of dried blood spots (DBS). All the issues strictly connected to the chemical-physical characteristics of DBS and DESI (sample inhomogeneity, DBS support, DESI geometry and solvent) were carefully evaluated and innovative strategies were applied. Haematocrit was managed using a small and measured volume of blood (2 µL) with analysis of the entire DBS. RESULTS: The proposed method was fully validated in terms of limits of detection, limits of quantitation (LOQs; between 60 pg/mm2 and 1.6 ng/mm2 ), linearity (one order of magnitude starting from LOQs) and inter- and intra-day precision (on three levels, with relative standard deviation values not exceeding 17%). Accuracy was calculated by comparison with an ultrahigh-performance liquid chromatography-tandem mass spectrometry method (suitable also as a confirmatory method). CONCLUSIONS: Results showed a surprising sensitivity, demonstrating that this procedure could be suitable for applications in various fields, e.g. forensic analysis. Moreover, as a collateral benefit, it was discovered that the method is able to analyse very light traces left on plastic and glass surfaces by detached dried blood.