Assessing the efficacy of tabs on filtering facepiece respirator straps to increase proper doffing techniques while reducing contact transmission of pathogens

NIOSH-certified N95 filtering facepiece respirators (FFRs) are used in healthcare settings as a control measure to mitigate exposures to airborne infectious particles. When the outer surface of an FFR becomes contaminated, it presents a contact transmission risk to the wearer. The Centers for Disease Control and Prevention (CDC) guidance recommends that healthcare workers (HCWs) doff FFRs by grasping the straps at the back of the head to avoid contact with the potentially contaminated surface. Adherence to proper doffing technique is reportedly low due to numerous factors including difficulty in locating and grasping the straps. This study compares the impact of tabs placed on FFR straps to controls (without tabs) on proper doffing, ease of use and comfort, and reduction of transfer of contamination to the wearer. Utilizing a fluorescent agent as a tracer to track contamination from FFRs to hand and head areas of 20 human subjects demonstrated that there was no difference in tabbed FFR straps and controls with respect to promoting proper doffing (p = 0.48), but did make doffing easier (p = 0.04) as indicated by 7 of 8 subjects that used the tabs. Seven of the 20 subjects felt that FFRs with tabs were easier to remove, while only 2 of 20 indicated that FFRs without tabs were easier to remove. Discomfort was not a factor for either FFR strap type. When removing an FFR with contaminated hands, the use of the tabs significantly reduced the amount of tracer transfer compared to straps without tabs (p = 0.012). FFRs with tabs on the straps are associated with ease of doffing and significantly less transfer of the fluorescent tracer.     

Development and initial validation of the Respirator Comfort,Wearing Experience,and Function Instrument [R-COMFI]

Filtering face-piece respirators (FFRs) are worn to protect health care personnel from airborne particles; however, clinical studies have demonstrated that FFR adherence is relatively low in some settings, in part, due to discomfort and intolerance. The objective of this study was to develop and initially evaluate the psychometric properties of an instrument designed to measure the comfort and tolerability of FFRs.

Instrument items were developed through literature reviews, focus groups, and several iterations of ranking and refining by experts. Psychometric evaluation of the instrument was conducted using Rasch partial credit model (PCM) analysis. Pivot anchoring was used to specify the threshold defining item difficulty; in our analyses, this was the point that participants moved from possessing none of the trait to some of the trait.

The final instrument was completed by 165 health care personnel from 3 Veterans Health Administration facilities, and data were analyzed using Rasch PCM. Seven items were removed because they: (1) violated the assumption of independence; (2) were mis-fitting; and/or (3) were deemed not relevant. Category function analysis demonstrated that all categories progressed monotonically. Principal components analysis demonstrated the existence of three subscales (Discomfort, General Wearing Experience, and Function). Final reliability analyses showed that the scale had moderate to high person reliability and high item reliability. The final instrument contained 21 items.

Until now, to our knowledge no instrument with evidence supporting its reliability and validity to assess discomfort and tolerance of FFRs among health care personnel has been published. A 21-item psychometrically sound measure of comfort and tolerability of FFRs, Respirator Comfort, Wearing Experience, and Function Instrument (R-COMFI), was developed. The significance of developing such an instrument is that it will help identify respirators that are likely to have better adherence in practice settings. The R-COMFI may be used within and beyond the VA healthcare system as a psychometrically sound instrument to evaluate the comfort and tolerability of respirators, including developmental prototypes.     

Development of an Advanced Respirator Fit-Test Headform

Improved respirator test headforms are needed to measure the fit of N95 filtering facepiece respirators (FFRs) for protection studies against viable airborne particles. A Static (i.e., non-moving, non-speaking) Advanced Headform (StAH) was developed for evaluating the fit of N95 FFRs. The StAH was developed based on the anthropometric dimensions of a digital headform reported by the National Institute for Occupational Safety and Health (NIOSH) and has a silicone polymer skin with defined local tissue thicknesses. Quantitative fit factor evaluations were performed on seven N95 FFR models of various sizes and designs. Donnings were performed with and without a pre-test leak checking method. For each method, four replicate FFR samples of each of the seven models were tested with two donnings per replicate, resulting in a total of 56 tests per donning method. Each fit factor evaluation was comprised of three 86-sec exercises: “Normal Breathing” (NB, 11.2 liters per min (lpm)), “Deep Breathing” (DB, 20.4 lpm), then NB again. A fit factor for each exercise and an overall test fit factor were obtained. Analysis of variance methods were used to identify statistical differences among fit factors (analyzed as logarithms) for different FFR models, exercises, and testing methods. For each FFR model and for each testing method, the NB and DB fit factor data were not significantly different (P > 0.05). Significant differences were seen in the overall exercise fit factor data for the two donning methods among all FFR models (pooled data) and in the overall exercise fit factor data for the two testing methods within certain models. Utilization of the leak checking method improved the rate of obtaining overall exercise fit factors ≥100. The FFR models, which are expected to achieve overall fit factors ≥ 100 on human subjects, achieved overall exercise fit factors ≥ 100 on the StAH. Further research is needed to evaluate the correlation of FFRs fitted on the StAH to FFRs fitted on people.

[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a file providing detailed information on the advanced head form design and fabrication process.]     

Persistence of Respirator Use Learning

Although retraining and repeat fit-testing are needed for respirator users, the optimal frequency is uncertain. The persistence of proper respirator donning/doffing techniques and changes in quantitative fit factor over 6 months after initial training were measured in this study. Initial training was designed for rapid rollout situations in which direct contact with well-trained occupational health professionals may be infeasible. Subjects (n = 175) were assigned randomly to use either a filtering facepiece N95 (FFR) or dual cartridge half facemask (HFM) respirator. Each was assigned randomly to one of three training methods—printed brochure, video, or computer-based training. Soon after initial training, quantitative fit and measures of proper technique were determined. These measurements were repeated 6 months later. In the six-month followup, subjects were randomized to receive either a brief reminder card or a placebo card. Total performance score, major errors, and quantitative fit all became significantly worse at 6 months. An individual's result soon after training was the most important predictor of performance 6 months later. There was a marginal not statistically significant tendency for those initially trained by video to have better protection 6 months later. The study suggests that persons who use respirators intermittently should be thoroughly retrained and reevaluated periodically.

[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: Additional statistical analyses.     

Performance of two respiratory protective devices used by home-attending health care workers (a pilot study)

Objectives: This pilot study aimed at determining the Workplace Protection Factor (WPF) for respiratory protective devices widely used by health care workers to reduce exposure to potentially hazardous aerosols when attending patients in their homes. Two devices were tested, an N95 filtering facepiece respirator (FFR) and a surgical mask (SM).

Methods: Three home-attending health care workers were recruited, medically cleared and fit tested. At the workplace, the aerosol concentrations outside (C_out) and inside (C_in) of the tested respiratory protective device worn by a subject were measured using two simultaneously operating P-Trak condensation particle counters within the particle size range of approximately 20–1,000 nm. Real-time and integrated (time-weighted average, TWA) values of WPF = C_out/C_in were determined.

Results: This pilot study demonstrated that the WPF of the tested N95 FFR consistently exceeded that of the SM. The WPF_TWA(C) values calculated for the entire test time (based on the TWA aerosol concentration values) ranged from 29 to 40 and 2 to 9, respectively. In all cases, the N95 FFR provided protection above the Occupational Safety and Health Administration's (OSHA) assigned protection factor of 10, whereas the SM often offered little or essentially no protection against the measured sub-micrometer aerosol particles. For both devices, the protection level was found to depend on activity. For example, the WPF_TWA(C) for one subject wearing the N95 FFR was 56 during normal activity but fell almost 70% during tracheal suctioning. It is explicable considering that different procedures implemented by health care workers in homes generate particles of different sizes and require different body movements; both factors are anticipated to affect the WPF.

Conclusions: Wearing an N95-certified respirator helps significantly reduce the aerosol inhalation exposure of home-attending health care workers. An SM offers much lower protection. The WPF depends on several factors, including, but not limited to, the health care worker's activity and/or body movements; the WPF varies from one worker to another.     

Inward leakage variability between respirator fit test panels – Part II. Probabilistic approach

This study aimed to quantify the variability between different anthropometric panels in determining the inward leakage (IL) of N95 filtering facepiece respirators (FFRs) and elastomeric half-mask respirators (EHRs).

We enrolled 144 experienced and non-experienced users as subjects in this study. Each subject was assigned five randomly selected FFRs and five EHRs, and performed quantitative fit tests to measure IL. Based on the NIOSH bivariate fit test panel, we randomly sampled 10,000 pairs of anthropometric 35 and 25 member panels without replacement from the 144 study subjects. For each pair of the sampled panels, a Chi-Square test was used to test the hypothesis that the passing rates for the two panels were not different. The probability of passing the IL test for each respirator was also determined from the 20,000 panels and by using binomial calculation. We also randomly sampled 500,000 panels with replacement to estimate the coefficient of variation (CV) for inter-panel variability.

For both 35 and 25 member panels, the probability that passing rates were not significantly different between two randomly sampled pairs of panels was higher than 95% for all respirators. All efficient (passing rate ≥80%) and inefficient (passing rate ≤60%) respirators yielded consistent results (probability >90%) for two randomly sampled panels. Somewhat efficient respirators (passing rate between 60% and 80%) yielded inconsistent results. The passing probabilities and error rates were found to be significantly different between the simulation and binomial calculation. The CV for the 35-member panel was 16.7%, which was slightly lower than that for the 25-member panel (19.8%).

Our results suggested that IL inter-panel variability exists, but is relatively small. The variability may be affected by passing level and passing rate. Facial dimension-based fit test panel stratification was also found to have significant impact on inter-panel variability, i.e., it can reduce alpha and beta errors, and inter-panel variability.     

Family history tools for primary care are not ready yet to be implemented. A systematic review

Background: Taking the family history helps the doctor in estimating the probability of disease in individual patients. However, significant barriers to obtaining adequate family history information remain. Tools overcoming these barriers might support family physicians in this task.

Objective: To review systematically the characteristics of existing family history tools and discuss their potential use in primary care.

Methods: Studies were identified through searches of PubMed, Embase and Cinahl from 1 January 2002 until May 2012. All authors independently screened studies and included original research papers on family history tools of which assessment had been performed or was planned. We reviewed diseases for which family history information was collected, study setting, tool design, type of family history collection, presence of risk-assessment and recommendations for management, and assessment (categorized as either validity or benefit).

Results: Eighteen family history tools were identified: six generic, two on cardiovascular disease and ten on cancer. The six generic tools were partly tested in primary care (3x), are mainly computerized (4x), rarely include management recommendations for the physician (1x) and were partly validated against a reference standard (genetic counsellor) (3x, plus one planned). Of the five specific tools studied in primary care, none was validated. No family history tool allows electronic transfer of family history information to electronic medical record systems. Use of a family history tool improved identification of patients at risk for disease.

Conclusion: Several promising family history tools for primary care have been developed but large-scale implementation cannot be advised yet, based on available validation studies.     

Managing occupations in everyday life for people with advanced cancer living at home

Background: People with advanced cancer are able to live for extended periods of time. Advanced cancer can cause functional limitations influencing the ability to manage occupations. Although studies have shown that people with advanced cancer experience occupational difficulties, there is only limited research that specifically explores how these occupational difficulties are managed.

Objective: To describe and explore how people with advanced cancer manage occupations when living at home.

Material and methods: A sub-sample of 73 participants from a larger occupational therapy project took part in the study. The participants were consecutively recruited from a Danish university hospital. Qualitative interviews were performed at the homes of the participants. Content analysis was applied to the data.

Results: Managing occupations were manifested in two main categories; (1) Conditions influencing occupations in everyday life and (2) Self-developed strategies to manage occupations.

Significance: The findings suggest that people with advanced cancer should be supported to a greater extent in finding ways to manage familiar as well as new and more personally meaningful occupations to enhance quality of life.     

Bullying victimization as a mediator of associations between cultural/familial variables,substance use,and depressive symptoms among Hispanic youth

Objectives. This article examines the antecedents and consequences of bullying victimization among a sample of Hispanic high school students. Although cultural and familial variables have been examined as potential risk or protective factors for substance use and depression, previous studies have not examined the role of peer victimization in these processes. We evaluated a conceptual model in which cultural and familial factors influenced the risk of victimization, which in turn influenced the risk of substance use and depression.

Design. Data were collected as part of a longitudinal survey study of 9th and 10th grade Hispanic/Latino students in Southern California (n = 1167). The student bodies were at least 70% Hispanic/Latino with a range of socioeconomic characteristics represented. We used linear and logistic regression models to test hypothesized relationships between cultural and familial factors and depression and substance use. We used a mediational model to assess whether bullying victimization mediated these associations.

Results.Acculturative stress and family cohesion were significantly associated with bullying victimization. Family cohesion was associate d with depression and substance use. Social support was associated with alcohol use. Acculturative stress was associated with higher depression. The associations between acculturative stress and depression, family cohesion and depression, and family cohesion and cigarette use were mediated by bullying victimization.

Conclusion. These findings provide valuable information to the growing, but still limited, literature about the cultural barriers and strengths that are intrinsic to the transition from adolescence to emerging adulthood among Hispanic youth. Our findings are consistent with a mediational model in which cultural/familial factors influence the risk of peer victimization, which in turn influences depressive symptoms and smoking, suggesting the potential positive benefits of school-based programs that facilitate the development of coping skills for students experiencing cultural and familial stressors.     

Frequency and evaluation of the perceptions towards caesarean section among pregnant women attending public hospitals in Pakistan and the implications

Objectives: There is increasing prevalence of caesarean sections (CS) worldwide; however, there are concerns about their rates in some countries, including potential fears among mothers. Consequently, we aimed to determine the frequency of CS, and explore patient’s perception towards CS attending public hospitals in Pakistan, to provide future guidance.

Methods: A two-phased study design (retrospective and cross sectional) was adopted. A retrospective study was conducted to assess the frequency of CS over one year among four public hospitals. A cross sectional study was subsequently conducted to determine patients’ perception towards CS attending the four tertiary care public hospitals in Quetta city, Pakistan, which is where most births take place.

Results: Overall prevalence of CS was 13.1% across the four hospitals. 728 patients were approached and 717 responded to the survey. Although 78.8% perceived CS as dangerous, influenced by education (p = 0.004), locality (p = 0.001) and employment status (p = 0.001), 74.5% of patients were in agreement that this is the best approach to save mother’s and baby’s lives if needed. 62% of respondents reported they would like to avoid CS if they could due to post-operative pain, and 58.9% preferred a normal delivery. There was also a significant association with education (p = 0.001) and locality (p = 0.001) where respondents considered normal vaginal delivery as painful.

Conclusion: The overall frequency of CS approximates to WHO recommendations, although there is appreciable variation among the four hospitals. When it comes to perception towards CS, women had limited information. There is a need to provide mothers with education during the antenatal period, especially those with limited education, to accept CS where needed.     

Dangerous (toxic) atmospheres in UK wood pellet and wood chip fuel storage

There is growing use of wood pellet and wood chip boilers in the UK. Elsewhere fatalities have been reported, caused by carbon monoxide poisoning following entry into wood pellet storage areas. The aim of this work was to obtain information on how safely these two fuels are being stored in the UK.

Site visits were made to six small-scale boiler systems and one large-scale pellet warehouse, to assess storage practice, risk management systems and controls, user knowledge, and potential for exposure to dangerous atmospheres. Real time measurements were made of gases in the store rooms and during laboratory tests on pellets and chips. Volatile organic compounds (VOCs) emitted and the microbiological content of the fuel was also determined.

Knowledge of the hazards associated with these fuels, including confined space entry, was found to be limited at the smaller sites, but greater at the large pellet warehouse. There has been limited risk communication between companies supplying and maintaining boilers, those manufacturing and supplying fuel, and users. Risk is controlled by restricting access to the store rooms with locked entries; some store rooms have warning signs and carbon monoxide alarms. Nevertheless, some store rooms are accessed for inspection and maintenance.

Laboratory tests showed that potentially dangerous atmospheres of carbon monoxide and carbon dioxide, with depleted levels of oxygen may be generated by these fuels, but this was not observed at the sites visited. Unplanned ventilation within store rooms was thought to be reducing the build-up of dangerous atmospheres. Microbiological contamination was confined to wood chips.     

Determining Barriers to Use of Edible School Gardens in Illinois

Objective: The objective of this study was to gather data regarding the awareness, perceived benefits, interest in, and barriers to establishment of edible school gardens in Illinois public schools.

Method: Setting/Design: This study used an online survey design. Participants: Participants included Illinois public elementary school principals and superintendents. Variables measured: Region and community population, current edible garden use, perception (Likert scale) of garden benefits, interest in establishment of a school edible garden, and barriers to establishment of a school edible garden were the variables of interest.

Analyses: Logit regression and Kruskal-Wallis with follow-up where p < 0.05 were performed.

Results: Elementary school principals and superintendents are aware of gardens and their potential benefits to students, but many barriers exist that make their use challenging. Funding, staff and volunteer support, and class time were identified as the major barriers. Region affected likelihood of garden use, and community population size also affected the odds of having an edible school garden.

Conclusion and implications: Data suggest that edible garden use would increase with provision of resources and organization of dedicated supporters.     

Dietary recommendations for the prevention of depression

Background: Major depressive disorder is a common, chronic condition that imposes a substantial burden of disability globally. As current treatments are estimated to address only one-third of the disease burden of depressive disorders, there is a need for new approaches to prevent depression or to delay its progression. While in its early stages, converging evidence from laboratory, population research, and clinical trials now suggests that dietary patterns and specific dietary factors may influence the risk for depression. However, largely as a result of the recency of the nutritional psychiatry field, there are currently no dietary recommendations for depression.

Aim: The aim of this paper is to provide a set of practical dietary recommendations for the prevention of depression, based on the best available current evidence, in order to inform public health and clinical recommendations.

Results: Five key dietary recommendations for the prevention of depression emerged from current published evidence. These comprise: (1) follow ‘traditional’ dietary patterns, such as the Mediterranean, Norwegian, or Japanese diet; (2) increase consumption of fruits, vegetables, legumes, wholegrain cereals, nuts, and seeds; (3) include a high consumption of foods rich in omega-3 polyunsaturated fatty acids; (4) replace unhealthy foods with wholesome nutritious foods; (5) limit your intake of processed-foods, ‘fast’ foods, commercial bakery goods, and sweets.

Conclusion: Although there are a number of gaps in the scientific literature to date, existing evidence suggests that a combination of healthful dietary practices may reduce the risk of developing depression. It is imperative to remain mindful of any protective effects that are likely to come from the cumulative and synergic effect of nutrients that comprise the whole-diet, rather than from the effects of individual nutrients or single foods. As the body of evidence grows from controlled intervention studies on dietary patterns and depression, these recommendations should be modified accordingly.     

Extending viability of Lactobacillus plantarum and Lactobacillus johnsonii by microencapsulation in alginate microgels

Aim: To investigate whether microencapsulation of Lactobacillus in alginate microbeads will lead to increased longevity during refrigerated storage or simulated digestion.

Materials and methods: Microscopy was used to confirm that Lactobacillus plantarum ATCC BAA-793 and Lactobacillus johnsonii ATCC 33200 were immobilised within the microbeads and laser scattering analysis was used to determine the mean diameter of the microbeads. The number of viable cells were enumerated throughout refrigerated storage and simulated digestion experiments.

Results: Microencapsulation was shown to have differing effects on viability depending on the species, but led to extended viability during refrigerated storage and simulated digestion in L. johnsonii and L. plantarum respectively.

Conclusion: Fermented functional foods contain microbes beneficial to human health. However, extended shelf storage and the harsh environment of the GI tract significantly reduces the number of viable microbes reaching the consumer. Microencapsulation allows beneficial microbes to reach the gut of the consumer in higher numbers, and thus confer greater health benefits.     

Antinociceptive and antiallodynic effects of Momordica charantia L. in tibial and sural nerve transection-induced neuropathic pain in rats

Objective

This study was designed to investigate the ameliorative potential of Momordica charantia L. (MC) in tibial and sural nerve transection (TST)-induced neuropathic pain in rats.

Materials and methods

TST was performed by sectioning tibial and sural nerve portions (2 mm) of the sciatic nerve, and leaving the common peroneal nerve intact. Acetone drop, pin-prick, hot plate, paint-brush, and walking track tests were performed to assess cold allodynia, mechanical and heat hyperalgesia, and dynamic mechanical allodynia and tibial functional index, respectively. The levels of tumour necrosis factor (TNF)-alpha and thio-barbituric acid reactive substances (TBARS) were measured in the sciatic nerve as an index of inflammation and oxidative stress. MC (all doses, orally, once daily) was administered to the rats for 24 consecutive days.

Results

TST led to significant development of cold allodynia, mechanical and heat hyperalgesia, dynamic mechanical allodynia, and functional deficit in walking along with rise in the levels of TBARS and TNF-alpha. Administration of MC (200, 400, and 800 mg/kg) significantly attenuated TST-induced behavioural and biochemical changes. Furthermore, pretreatment of BADGE (120 mg/kg, intraperitoneally) abolished the protective effect of MC in TST-induced neuropathic pain.

Conclusions

Collectively, it is speculated that PPAR-gamma agonistic activity, anti-inflammatory, and antioxidative potential is critical for antinociceptive effect of MC in neuropathic pain.     

Striatal mitochondria response to 3-nitropropionic acid and fish oil treatment

Background: Mitochondrial dysfunction is involved in neurodegenerative diseases, such as Huntington's disease (HD). 3-Nitropropionic acid (3-NP) is a mitochondrial toxin that specifically inhibits complex II of the electron transport chain (ETC) and is used to generate an experimental model of HD.

Objective: To study the effect of fish liver oil (FO) over the mitochondrial dysfunction induced via partial ETC inhibition by 3-NP.

Methods: This study was performed in rats and consisted of two phases: (i) administration of increasing doses of 3-NP and (ii) administration of FO for 14 days before to 3-NP. The rats’ exploratory activity; complex I, II, III, and IV activities; and rearing behavior were observed. Additionally, the number of TUNEL-positive cells and various mitochondrial parameters, including oxygen consumption, transmembrane potential, adenosine triphosphate synthesis, and ETC activity, were measured.

Results: We observed that FO exerted a protective effect against the 3-NP-induced toxicity, although complex II inhibition still occurred. Instead, this effect was related to strengthened mitochondrial complex III and IV activities.

Discussion: Our results show that FO exerts a beneficial prophylactic effect against mitochondrial damage. Elucidating the mechanisms linking the effects of FO with its prevention of neurodegeneration could be the key to developing recommendations for FO consumption in neurological pathologies.     

A pilot study evaluating the prescribing of ceftriaxone in hospitals in Ghana: findings and implications

Background and Objectives: Widespread empiric use of antibiotics exists especially in developing countries. This is a concern since inappropriate use of antibiotics, including their extended inappropriate use, will increase resistance rates. Consequently, there is a need to evaluate antibiotic utilisation across healthcare sectors to improve future use. This includes ceftriaxone, widely used among hospitals including those in Ghana.

Methods: A cross-sectional study to evaluate the appropriateness of ceftriaxone prescribing in a leading hospital in Ghana. Ceftriaxone prescribing in patient-record cards was assessed using a modified WHO drug-utilization evaluation criteria as well as referencing the national standard treatment guidelines in Ghana and the ceftriaxone package insert.

Results: A total of 251 patients were assessed. Ceftriaxone was most commonly prescribed for comorbid malaria with bacterial infections, urinary tract infections, sepsis and gastroenteritis. The appropriateness of the indication was 86% (n = 218). The doses most prescribed were 1g (41%) and 2g (39%). Stat dose and once-daily dosage regimen constituted 51.4% and 84.5%, respectively. The most common duration of treatment was 1 (51.4%) and 2 days (35.1%). The overall appropriateness of prescribing was 93% against a pre-set threshold of 97%.

Conclusion: The appropriateness of ceftriaxone prescribing was high in this leading hospital in Ghana; however, there is room for improvement with targeted education initiatives, with further research planned.     

Strategies for diagnosing leg oedema in primary care: A qualitative study of GPs’ approaches

Background: The symptom leg oedema represents a broad range of possible underlying aetiologies. The background of leg oedema is multifactorial and usually the GP is the first contact point for patients presenting with this symptom. GPs rely on patient history and physical examination as their main diagnostic tools.

Objective: To identify GPs’ diagnostic approaches and heuristics in patients presenting with leg oedema.

Methods: Interviews with 15 GPs (20–30 min) using a semi-structured interview-guideline were conducted. GPs described their individual diagnostic strategies concerning all patients presenting with leg oedema they had prospectively identified during the previous four weeks. Interviews were taped and transcribed verbatim. Qualitative analysis was conducted by two independent raters.

Results: GPs applied a variety of diagnostic approaches, which can be grouped in active and passive strategies. Active strategies comprised the use of decision rules and guidelines, Bayesian arguing, problem dichotomisation and discrepancy heuristics. Passive approaches included test of time, therapy as diagnosis, and taking patient assumptions into account.

Conclusion: When dealing with leg oedema, GPs use prior information of individual patients in a specific way. There is a broad variety of diagnostic approaches that can be grouped in ‘active’ and ‘passive’ behaviour. Approaches mostly match with established diagnostic strategies in primary care.     

Effects of zinc supplementation on efficacy of antidepressant therapy,inflammatory cytokines,and brain-derived neurotrophic factor in patients with major depression

Objective

Zinc is found in abundance in the human brain. Patients with depression may have decreased consumption of food sources rich in zinc, and zinc supplementation may have a potential influence on depressive symptoms. However, clinical trials on the effect of zinc supplementation in depression are limited. The objective of the present study was to determine the effect of zinc supplementation on efficacy of antidepressant therapy. Furthermore, the effect of zinc on plasma levels of interleukin-6 (IL-6), tumor necrosis factor (TNF-α), and brain-derived neurotrophic factor-a (BDNF-a) were assessed.

Design

A single-center, randomized, double-blind, placebo-controlled trial of zinc supplementation was conducted in patients with DSM-IV major depression. Forty-four patients of both sexes aged 18–55 years were recruited for this study from a university hospital. The zinc-supplemented group received zinc sulfate (25 mg elemental Zn/day) orally in addition to their selective serotonin reuptake inhibitor antidepressants for 12 weeks. Symptoms were evaluated using the Hamilton Depression Rating Scale (HDRS) on arrival, weeks 6 and 12. Plasma levels of IL-6, TNF-α and BDNF-a were measured at baseline and at the end of study.

Results

Twenty patients in zinc group and 17 patients in placebo groups completed the study. At baseline, there were no significant differences in any variable between the patients allocated to receive placebo and those taking zinc supplement. Zinc supplementation significantly reduced HDRS compared to placebo (P < 0.01 at 12th week). No significant differences were observed in plasma levels of IL-6, TNF-α, and BDNF-a between zinc-supplemented and placebo-supplemented group.

Conclusion

Zinc supplementation in conjunction with antidepressant drugs might be beneficial for reducing depressive symptoms. However, its effect does not appear to be mediated through impact of zinc on inflammatory processes.