A health-related quality of life measure for use in patients with onychomycosis: a validation study

Severe drug eruption from oral terbinafine for mild onychomycosis-A case report from family practice and literature review: "Just an innocent little pill?"

Onychomycosis is the most prevalent nail disease and is frequently encountered in clinical practice. Despite having multiple therapeutic options, of which systemic antifungals are the most effective, treatment is not always mandatory in all patients. Especially when considering systemic treatment, the risk of adverse reactions may outweigh the potential benefits of treatment. In this case report, we present a clinical case of a 49-year-old male patient with a blank past medical history who experienced a severe drug eruption from terbinafine prescribed for mild onychomycosis that required discontinuation of terbinafine, additional evaluation, and treatment of this adverse reaction.

Development and Validation of a Patient-Reported Outcome Measure for Fingernail and Toenail Conditions: The NAIL-Q

Background

Patient-reported outcome measures (PROMs) are needed to measure outcomes that matter to people with nail conditions, from their perspective.

Objective

To design a comprehensive new PROM (NAIL-Q) to measure outcomes important in toenail and fingernail conditions.

Methods

A mixed methods iterative approach was used. Phase 1 involved concept elicitation interviews that were audio-recorded, transcribed, and coded line-by-line. Concepts were developed into scales and refined through cognitive debriefing interviews with patients and expert input. Data was then collected from an international sample using a crowdsource platform. Eligible participants were aged ≥18 years with a nail condition for at least 3 months. Rasch Measurement Theory (RMT) analysis was used to examine item and scale performance. Other psychometric tests included test-retest reliability, and convergent and construct validity.

Results

Phase 1 interviews involved 23 patients with 10 nail conditions and input from 11 dermatologists. The analysis led to the development of 84 items for field-testing. In Phase 2, 555 participants completed the survey. Toenail conditions (n = 441) were more common than fingernail conditions (n = 186). The RMT analysis reduced the number of items tested to 45 in 7 scales measuring nail appearance, health-related quality of life concerns, and treatment outcomes. All items had ordered thresholds and nonsignificant chi-square p values. Reliability statistics with and without extremes for the Person Separation Index were ≥0.79 and Cronbach's alpha were ≥0.83, and for intraclass correlation coefficients were ≥0.81. Construct validity was further supported in that most participants agreed that the NAIL-Q was easy to understand, asked relevant and important questions in a respectful way, and that it should be used to inform clinical care.

Conclusion

The NAIL-Q is a rigorously designed and tested PROM that measures nail appearance, health-related quality of life and treatment outcomes. This PROM can be used in clinical practice to inform patient care and to include the patient perspective in research.

The accuracy of clinical diagnosis of onychomycosis in Dutch general practice: a diagnostic accuracy study

BACKGROUND

Onychomycosis, the most common cause of nail dystrophy, is generally diagnosed by clinical examination. Current guidelines for Dutch general practice advise confirmatory testing only in cases of doubt or insufficient response to treatment. However, making a correct diagnosis can be challenging given the wide variety of clinical features and differential diagnosis.

AIM

To establish accuracy of clinical diagnosis of onychomycosis by GPs.

DESIGN & SETTING

A diagnostic accuracy study based on GPs' clinical diagnosis of primary care patients suspected of onychomycosis.

METHOD

Using 137 complete datasets from the Onycho Trial, diagnostic accuracy of clinical diagnosis as the index test was compared with confirmatory testing as the reference test. A sensitivity analysis was performed to determine diagnostic values for different combinations of index and reference test. Logistical regression was used to assess which clinical characteristics were associated with the positive predictive value (PPV) of the index test.

RESULTS

Clinical accuracy, that is the PPV of the index test, was 74.5%. Sensitivity analysis showed no significant difference in diagnostic values. Male sex and a history of any previous treatment significantly increased clinical accuracy with an odds ratio (OR) of 3.873 (95% confidence interval [CI] = 1.230 to 12.195, P = 0.021) and OR 4.022 (95% CI = 1.075 to 15.040, P = 0.039), respectively.

CONCLUSION

The study demonstrated that the GPs' clinical diagnosis of onychomycosis was insufficiently accurate to initiate treatment without confirmatory testing. Further research is needed to investigate how to increase clinical accuracy and reduce potentially unnecessary exposure to treatment.

Patient-reported outcome measures for patients with nail conditions: a systematic review of the psychometric evidence

Nail conditions have an impact on appearance, function, and quality of life of patients. Patient reported outcome measures (PROMs) are important tools for evaluating treatment success from the patient perspective. It is important to understand the quality of PROMs to help guide selection of appropriate tools. The aim of this study was to critically appraise the psychometric properties of nail-specific PROMs using COSMIN guidelines. A systematic review was conducted in May 2019 to identify development and validation articles for nail-specific PROMs. Abstracts and subsequent full-texts were screened by two reviewers for eligibility. Data were extracted for study characteristics and psychometric properties. The risk of bias checklist was completed, and ratings applied to psychometric properties as per COSMIN guidelines. Modified Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria were applied based on the risk of bias checklist to assess methodological quality. The review identified 3289 articles of which 430 full-text articles were screened, nine of which met eligibility criteria. Included papers were for seven PROMs and in total reported on 31of 49 possible measurement properties. Of the 31 measurement properties reported, nine (29%) were rated as insufficient or indeterminate. The modified GRADE methodological quality rating was low or very low for 16 (32.7%) measurement properties, and 18 (36.7%) measurement properties were not described by any PROM. Currently there are no nail-specific PROMS available that demonstrate adequate validity, reliability, or responsiveness, according to COSMIN guidelines. Further research is required to assess missing or insufficiently tested measurement properties in all the PROMs identified.

Effect of onychomycosis and treatment on patient-reported quality-of-life outcomes: A systematic review

BACKGROUND

Onychomycosis is the most common nail disorder, often causing physical, emotional, and aesthetic consequences. The effect of both the condition itself and treatment on quality of life has not been well studied.

OBJECTIVE

The objectives of this study were to systematically review the available literature describing the effect of onychomycosis and treatment on quality of life.

METHODS

We performed a search of the onychomycosis literature published before April 13, 2020. Articles were included in the review if primary data were presented, patient-reported outcome measures were used, and onychomycosis was specifically examined.

RESULTS

Thirty studies were included in the final analysis. Poorest quality-of-life scores were associated with women and fingernail involvement. Quality-of-life scores improved from baseline with all treatment types; there were greater improvements reported with oral treatments compared with topical ones.

CONCLUSIONS

This review affirms that onychomycosis significantly influences quality of life, warranting effective treatment. All treatments resulted in quality-of-life improvements; however, studies on oral and topical therapies were of higher quality than those evaluating devices. Increased efforts are needed to understand the effect of the disease and therapy as assessed by validated, nail-specific outcome measures that accurately assess patients' cosmetic, physical, and social difficulties.

A practical application of onychomycosis cure - combining patient, physician and regulatory body perspectives

Due to the high relapse rates and the rise of predisposing factors, the need for curing onychomycosis is paramount. To effectively address onychomycosis, the definition of cure used in a clinical setting should be agreed upon and applied homogeneously across therapies (e.g. oral, topical and laser treatments). In order to determine what is or what should be used to define cure in a clinical setting, a literature search was conducted to identify methods used to evaluate treatment success. The limitations, strengths, prevalence and utility of each outcome measure were investigated. Seven ways to measure treatment success were identified; mycological cure, patient/investigator assessments, complete cure, quality of life instruments, severity indexes, clinical cure and temporary clearance. Despite its shortcomings, mycological cure is the most objective and consistent outcome measure used across onychomycosis studies. It is suggested that diagnostic goals of onychomycosis should be used to define cure in a clinical setting. Modifications to outcome measures such as incorporating molecular-based techniques could be a future avenue to explore.

The Impact of Onychomycosis on Quality of Life: A Systematic Review of the Available Literature

Purpose

Onychomycosis is a nail disorder that is increasing in prevalence worldwide. The psychological and social limitations caused by onychomycosis can potentially undermine the work and social lives of those experiencing these negative effects. This review aimed to evaluate the randomized controlled trials (RCTs) available in the current literature on the impact onychomycosis has on quality of life (QoL).

Methods

A systematic review was performed using the databases PubMed, PsycINFO, Scopus, ClinicalTrials.gov, and Cochrane Library on July 18, 2017. Only RCTs with clinical effects described in English were included for review.

Results

Ten RCTs reported QoL outcomes for patients suffering from onychomycosis. Treatment satisfaction was statistically significant from baseline to end of treatment in 100.0% (4/4) measures which reported on satisfaction with treatment; mental health was also significant in 100.0% (3/3), symptoms index rating in 100.0% (2/2), symptom frequency in 75.0% (3/4), overall problems in 75.0% (3/4), functional activities in 75.0% (6/8), appearance problems in 66.7% (2/3), symptom distress in 57.1% (4/7), and stigma in 40.0% (2/5). The OnyCOE-t^TM and the NailQoL were the most used common outcome measures to describe QoL.

Conclusion

The study sanctions that onychomycosis physically and psychologically distresses patients' lives. Further research should include validated outcome measures to more effectively treat onychomycosis.

Patient-Reported Outcomes in Onychomycosis: A Review of Psychometrically Evaluated Instruments in Assessing Treatment Effectiveness

PURPOSE

Onychomycosis is the most common nail disorder and causes morbidity and impaired quality of life (QOL). Patient-reported outcomes (PRO) are patients' assessment of their health status or treatment response. PROs help assess what is most bothersome to patients to identify targets for intervention. We sought to review the PRO instruments currently used to assess QOL and treatment response in onychomycosis patients.

PROCEDURES

A systematic review was performed by searching PubMed, Embase, CINAHL, and PsycINFO databases through December 31, 2016, to identify all English language literature on onychomycosis, PRO, and QOL.

RESULTS

Currently, 5 validated PRO instruments exist specifically for onychomycosis. Oral therapies were most extensively studied using PRO instruments. QOL data generally correlated with clinical change, although patients sometimes reported improvement without any clinically significant nail clearance. The only psychometrically validated PRO instrument used to evaluate treatment response is the OnyCOE-t™.

CONCLUSIONS

Clinicians may underestimate the impact of onychomycosis on patients. With recent initiatives from health-care management organizations to improve patient experience and the recent approval of expensive and nonsuperior topical antifungal medications, PROs will be increasingly important in onychomycosis to assess patient priorities and optimize treatment. Future research should evaluate these instruments in special populations and fingernail disease.

Update on therapy for superficial mycoses: review article part I

Superficial fungal infections of the hair, skin and nails are a major cause of morbidity in the world. Choosing the right treatment is not always simple because of the possibility of drug interactions and side effects. The first part of the article discusses the main treatments for superficial mycoses - keratophytoses, dermatophytosis, candidiasis, with a practical approach to the most commonly-used topical and systemic drugs , referring also to their dosage and duration of use. Promising new, antifungal therapeutic alternatives are also highlighted, as well as available options on the Brazilian and world markets.

Quality of life in patients with toenail onychomycosis

Onychomycosis is a common, chronic fungal nail infection that can have a significant negative impact on patients' physical and social functioning and emotional well-being. This study was undertaken to assess health-related quality of life (HRQoL) in patients with toenail onychomycosis. The Onychomycosis QoL questionnaire (ONYCHO), as a disease-specific instrument, and the Short Form 36 Health Survey (SF-36) as a generic instrument, were applied in 140 consecutive patients affected by onychomycosis. Women and patients who were experiencing toenail onychomycosis for more than 2 years were reporting worse disease-specific HRQoL. The patients working in blue-collar occupations and patients with greater involvement of individual nails were more affected by onychomycosis regarding symptoms. The results of this study confirm that although onychomycosis is not a life-threatening disease, it can significantly reduce patients' QoL.

Health-related quality of life in patients with nail disorders

Fingernails and toenails are important organs of our body, serving as protection for the tips of fingers and toes. Fingernails also enhance fine touching and tactile sensitivity, as well as aid in the picking up of small objects. Healthy-looking nails are an important part of an individual's body image, and any nail abnormalities may be considered by patients as a significant cosmetic problem, markedly influencing their self-esteem. However, recent data have indicated that nail lesions are not only important because of cosmetic disfigurement, but may be a symptom of significant morbidity. Severe nail involvement was also shown to negatively impair social functioning and to interfere with work ability, thus markedly influencing a patient's well-being. Based on literature data and our own experience we conclude that nail diseases cause a marked decrease in health-related quality of life in a substantial percentage of patients. Nail changes are an important medical concern for patients and, therefore, nail diseases should raise attention and receive proper care from both physicians and other healthcare providers.

The impact of aggressive debridement used as an adjunct therapy with terbinafine on perceptions of patients undergoing treatment for toenail onychomycosis

OBJECTIVE

To determine whether adding aggressive debridement to oral terbinafine for treating toenail onychomycosis impacts patient-reported outcomes (PROs).

MATERIALS AND METHODS

A total of 504 patients were randomized to receive 12 weeks of terbinafine 250 mg/day with or without debridement, with an additional 36-week follow-up. The OnyCOE-t, a validated disease-specific PRO questionnaire, was completed at baseline and weeks 6, 12, 24, and 48. It included six multi-item scales (symptom frequency, appearance problems, physical activities problems, stigma, and treatment satisfaction), and one single-item scale: overall problem. Longitudinal analysis of change was conducted to assess treatment effect. Repeated-measures models adjusted for visit, age, sex, baseline scores, severity and duration of infection; treatment interactions were also tested.

RESULTS

Symptom frequency and treatment satisfaction significantly improved in the terbinafine + debridement group compared with terbinafine alone (p = 0.0395 and p = 0.0077, respectively). Age and sex were often significant explanatory variables, and further analysis of change scores at 12 weeks revealed that females treated with terbinafine + debridement reported significantly less improvement in the physical activities problems (p = 0.0021) and overall problem (p = 0.0112) scores.

CONCLUSIONS

Aggressive debridement, when used as an adjunct therapy with oral terbinafine, improved treatment satisfaction and reduced symptom frequency. The observed sex differences warrant further investigation.

Evaluation of quality of life in patients with toenail onychomycosis by Polish version of an international onychomycosis-specific questionnaire

BACKGROUND

Onychomycosis is the most frequent nail disease, which could impair the patient's quality of life.

OBJECTIVE

The present study was undertaken to evaluate the impact of toenail onychomycosis on quality of life among Polish population.

PATIENTS AND METHODS

Three thousand nine-hundred and four (3904: 2269 females and 1635 males) individuals fulfilled an international onychomycosis-specific quality-of-life questionnaire consisting of statements regarding social, emotional and symptoms problems. All patients had toenail onychomycosis confirmed by the positive direct microscopic examination and/or by the positive mycologic culture. Seven hundred and sixty-seven patients simultaneously had fingernail onychomycosis. All patients were divided into subgroups according to sex, age, education level, place of living, type of onychomycosis, number of involved toenails, fingernails involvement, duration of illness and previously used antimycotic therapy.

RESULTS

Most of the patients demonstrated significantly reduced quality of life. The degree of life impairment varied between analysed subgroups. Patients with more advanced toenail onychomycosis and with fingernail involvement were more seriously affected. Both social and emotional impairments were more pronounced in female than in male patients, although there were no differences according to symptoms. Moreover, patients with better educational level and people living in towns or cities were more emotionally and socially affected by onychomycosis, although people living in the country or with poorer education level presented with significantly more severe symptoms.

CONCLUSIONS

Toenail onychomycosis is still a serious medical problem, which can significantly reduce the patient's quality of life.

Reliability of self-reported willingness-to-pay and annual income in patients treated for toenail onychomycosis

BACKGROUND

Willingness-to-pay (WTP) is a health economics measure that has recently been used for skin diseases to evaluate patients' quality of life. However, the reliability of this measure has not been investigated in the dermatology literature and is essential in validating its use in health services research.

OBJECTIVES

This study evaluated the test-retest reliability of self-reported annual income and WTP, a health economics measure of disease impact, in patients with toenail onychomycosis.

METHODS

Forty-six patients enrolled in a randomized clinical trial comparing two different dosing regimens of terbinafine completed a self-administered questionnaire at baseline and 1 month later. The questionnaire asked: (i) how much patients would be willing to pay for a theoretical treatment with a cure rate of 85% for their current onychomycosis (10 categories: $0-50, $51-100, to > $800); and (ii) annual income (10 categories: $0-10,000 to > $200,000).

RESULTS

Forty-four patients reported WTP at both visits, and 55% reported the same WTP. The quadratic-weighted (Fleiss-Cohen) kappa statistic indicated moderate agreement (kappa = 0.50, 95% confidence interval, CI 0.24-0.75, P < 0.01) as did the Spearman rank-order correlation coefficient (r(s) = 0.57, P < 0.01; median difference = 0, P = 0.50). Strong agreement was shown among the 42 patients who reported income at both visits; 71% reported the same annual income category (kappa = 0.72, 95% CI 0.47-0.96, P < 0.01; r(s) = 0.68, P < 0.01; median difference = 0, P = 0.77). Age, disease severity and duration, previous therapy, self-reported annual income, and medication side-effects were not statistically associated with the reliability of WTP.

CONCLUSIONS

WTP and annual income demonstrated moderate and strong test-retest reliability, respectively. Self-reported WTP can serve as a reliable measure for future health economics research on onychomycosis.

A survey of self-reported outcome instruments for the foot and ankle

The information acquired from self-reported outcome instruments is useful only if there is evidence to support the interpretation of obtained scores. To properly interpret scores, there should be evidence for content validity, construct validity, reliability, and responsiveness. Evidence regarding score interpretation must also contain a description of the applicable test conditions, including information about the characteristics of subjects, timing of data collection, and construct of change. The objective of this review was to identify self-reported outcome instruments that have evidence to support their usefulness for assessingthe effect of treatment directed at individuals with foot and ankle-related pathologic conditions in an orthopaedic physical therapy setting. In addition, we provide specific information that will allow clinicians and researchers to select an appropriate instrument and properly interpret the obtained scores. Fourteen self-reported outcome instruments that met the objective of this review were identified. Five instruments, the Foot and Ankle Ability Measure, Foot Function index, Foot Health Status Questionnaire, Lower Extremity Function Scale, and Sports Ankle Rating System quality of life measure, satisfied all 4 categories of evidence (content validity, construct validity, reliability, and responsiveness) outlined herein.

The OnyCOE-t questionnaire: responsiveness and clinical meaningfulness of a patient-reported outcomes questionnaire for toenail onychomycosis

Background

This research was conducted to confirm the validity and reliability and to assess the responsiveness and clinical meaningfulness of the OnyCOE-t^™, a questionnaire specifically designed to measure patient-reported outcomes (PRO) associated with toenail onychomycosis.

Methods

504 patients with toenail onychomycosis randomized to receive 12 weeks of terbinafine 250 mg/day with or without target toenail debridement in the IRON-CLAD^® trial completed the OnyCOE-t™ at baseline, weeks 6, 12, 24, and 48. The OnyCOE-t™ is composed of 6 multi-item scales and 1 single-item scale. These include a 7-item Toenail Symptom assessment, which comprises both Symptom Frequency and Symptom Bothersomeness scales; an 8-item Appearance Problems scale; a 7-item Physical Activities Problems scale; a 1-item Overall Problem scale; a 7-item Stigma scale; and a 3-item Treatment Satisfaction scale. In total, 33 toenail onychomycosis-specific items are included in the OnyCOE-t™. Clinical data, in particular the percent clearing of mycotic involvement in the target toenail, and OnyCOE-t™ responses were used to evaluate the questionnaire's reliability, validity, responsiveness, and the minimally clinical important difference (MCID).

Results

The OnyCOE-t™ was shown to be reliable and valid. Construct validity and known groups validity were acceptable. Internal consistency reliability of multi-item scales was demonstrated by Cronbach's alpha > .84. Responsiveness was good, with the Treatment Satisfaction, Symptom Frequency, Overall Problem, and Appearance Problem scales demonstrating the most responsiveness (Guyatt's statistic of 1.72, 1.31, 1.13, and 1.11, respectively). MCID was evaluated for three different clinical measures, and indicated that approximately an 8.5-point change (on a 0 to 100 scale) was clinically meaningful based on a 25% improvement in target nail clearing.

Conclusion

The OnyCOE-t™ questionnaire is a unique, toenail-specific PRO questionnaire that can be used with confidence in future studies of toenail onychomycosis. MCID was evaluated for three different clinical measures, and indicated that approximately a 7-point change (on a 0 to 100 scale) was clinically meaningful based on a 12.5% improvement in target nail clearing.

Brittle nail syndrome: a pathogenesis-based approach with a proposed grading system

Brittle nail syndrome is a heterogeneous abnormality, characterized by increased fragility of the nail plate. Brittle nails affect about 20% of the population and women are affected twice as frequently as men. The vast majority of patients experience brittle nails as a significant cosmetic problem and a substantial number indicate that these nail abnormalities are painful, impair daily activities, and may have a negative impact on occupational abilities. Pathogenic factors leading to brittle nails are factors that impair intercellular adhesion of the corneocytes of the nail plate or factors that cause a pathologic nail formation by involving the matrix. Clinical features of brittle nail syndrome are onychoschizia and onychorrhexis: the impairment of intercellular adhesive factors of the nail plate is expressed as onychoschizia, whereas the involvement of the nail matrix is expressed as onychorrhexis. Although impairment of life quality has not been evaluated for patients with brittle nail syndrome, the reduction of life quality in other nail problems has been studied and is evident. A proposed scoring system of key features of brittle nails is presented, and therapeutic approaches focussed on the pathogenic factors are discussed.

The oral antifungal patient

With the launch of the modern generation of oral antifungals almost a decade ago, an infection that was once thought of as intractable can now be cured. These drugs all offer the advantages of high efficacy rates, short-course therapy, and relative safety. However, they are far from perfect and not indicated in every situation. This article discusses issues such as patient selection, management, monitoring, and long-term follow-up.

Onychomycosis: health-related quality of life considerations

The symptoms of onychomycosis and their impact on personal appearance are important determinants of patients' perceptions of their own health. The effect of onychomycosis is greater on psychosocial than physical functioning and is directly related to the extent of nail involvement. This review identified a number of disease-targeted questionnaires that have been developed to assess the impact of onychomycosis and its treatment on health-related quality of life (HR-QOL). The instruments differ considerably in the extent to which they have been psychometrically tested. Most have been shown to provide both valid and reliable measurement of HR-QOL in patients with onychomycosis of the toes. However, not all have been tested in patients with fingernail disease. The generic and disease-targeted scales of most of the available questionnaires exhibit poor variability, which may limit their responsiveness to clinically important change. Only one instrument, the Onychomycosis Disease-Specific Questionnaire, has been incorporated into a clinical trial. Thus, information relating to the impact of onychomycosis treatment on HR-QOL is limited. Future efforts should focus on the systematic evaluation of existing questionnaires in all populations for which they were developed. In addition, it is important that disease-targeted measures be included in future clinical trials so that a better understanding of the impact of onychomycosis treatment on patient HR-QOL may be gained.

Cost of treatment for onychomycosis. Data from a 9-month observational study

OBJECTIVES

To estimate component and total costs of treatment and to examine differences in cost and cost effectiveness between oral antifungal medication and local therapy for patients with toenail onychomycosis.

DESIGN

Prospective, observational study of patients with onychomycosis who visited dermatologists and podiatrists in the US. Physicians provided data on clinical management, disease severity, nail improvement and resource utilisation. Patients completed questionnaires on resource utilisation and symptoms at base-line, 4 and 9 months. To estimate costs, reported utilisation was multiplied by unit costs expressed in 1997 US dollars ($US) and derived in 2 ways: first, using Medicare fees; and second, using standard physician fees.

RESULTS

After adjustment for key demographic and clinical variables, participants receiving oral medication had higher total costs based on standard fees ($US794 vs $US575) and medication costs ($US564 vs $US109), lower procedure costs ($US0 vs $US122) and physician visit costs ($US200 vs $US330), and greater clinical effectiveness as measured by global improvement rating (86 vs 35%) and Toenail Symptom Index (94 vs 49%). For participants receiving oral medication, 90% of total costs were incurred during the first 4 months of follow-up, whereas for those receiving local therapy, costs were more evenly distributed throughout the study period. Incremental cost-effectiveness analysis showed $US304 to $US491 per additional case improved with oral medication over a 9-month timeframe. Extrapolation of these results using 2 time-points (months 4 and 9) suggested that cost equivalence would be reached 17 to 21 months following the initiation of treatment.

CONCLUSIONS

During 9 months of follow-up in patients with toenail onychomycosis, the use of oral antifungal medication resulted in superior patient outcomes, but at higher total cost compared with local therapy.

Which antifungal agent for onychomycosis? A pharmacoeconomic analysis

The incidence of fungal nail infections is increasing and this is possibly because of several factors: better methods of detection, a growing population of immunocompromised patients who have a greater susceptibility to such infections, the increased use of immunosuppressive drugs, the increasing number of elderly people, worldwide travel, and the use of communal bathing facilities. Onychomycosis is a fungal infection of the fingernails and toenails that accounts for about 30% of all superficial fungal infections. It is characterised by nail discoloration, thickening and ultimately destruction of the nail plate. Management of this disease has improved significantly and treatment patterns have dramatically changed in recent years as a result of advances in new treatment options (e.g. oral antifungal agents) and changes in treatment regimens (e.g. pulse therapy). Also, newer drugs for onychomycosis have improved tolerability profiles compared with older agents. The overall costs of treating onychomycosis are substantial, and it has been estimated that direct cost for US Medicare patients with the disease is 43 million US dollars per year (year of costing not available). Pharmacoeconomic studies help in the decision-making process when selecting the most cost-effective antifungal agents to treat onychomycosis. To date there have been a number of national and international economic studies aimed at effectively assessing the efficacy and costs of the treatment options available to cure onychomycosis. The objectives of this paper are to (i) review the published findings regarding the epidemiology of onychomycosis; (ii) summarise the original pharmacoeconomic studies that describe the economic impact of the disease; and (iii) address the impact of the disease on patients' health-related quality of life.