The annual costs associated with human papillomavirus types 6, 11, 16, and 18 infections in Finland

Systematic review and evidence synthesis of non-cervical human papillomavirus-related disease health system costs and quality of life estimates

BACKGROUND

Many economic evaluations of human papillomavirus vaccination should ideally consider multiple disease outcomes, including anogenital warts, respiratory papillomatosis and non-cervical cancers (eg, anal, oropharyngeal, penile, vulvar and vaginal cancers). However, published economic evaluations largely relied on estimates from single studies or informal rapid literature reviews.

METHODS

We conducted a systematic review of articles up to June 2016 to identify costs and utility estimates admissible for an economic evaluation from a single-payer healthcare provider's perspective. Meta-analyses were performed for studies that used same utility elicitation tools for similar diseases. Costs were adjusted to 2016/2017 US$.

RESULTS

Sixty-one papers (35 costs; 24 utilities; 2 costs and utilities) were selected from 10 742 initial records. Cost per case ranges were US$124-US$883 (anogenital warts), US$6912-US$52 579 (head and neck cancers), US$12 936-US$51 571 (anal cancer), US$17 524-34 258 (vaginal cancer), US$14 686-US$28 502 (vulvar cancer) and US$9975-US$27 629 (penile cancer). The total cost for 14 adult patients with recurrent respiratory papillomatosis was US$137 601 (one paper).Utility per warts episode ranged from 0.651 to 1 (12 papers, various utility elicitation methods), with pooled mean EQ-5D and EQ-VAS of 0.86 (95% CI 0.85 to 0.87) and 0.74 (95% CI 0.74 to 0.75), respectively. Fifteen papers reported utilities in head and neck cancers with range 0.29 (95% CI 0.0 to 0.76) to 0.94 (95% CI 0.3 to 1.0). Mean utility reported ranged from 0.5 (95% CI 0.4 to 0.61) to 0.65 (95% CI 0.45 to 0.75) (anal cancer), 0.59 (95% CI 0.54 to 0.64) (vaginal cancer), 0.65 (95% CI 0.60 to 0.70) (vulvar cancer) and 0.79 (95% CI 0.74 to 0.84) (penile cancer).

CONCLUSIONS

Differences in values reported from each paper reflect variations in cancer site, disease stages, study population, treatment modality/setting and utility elicitation methods used. As patient management changes over time, corresponding effects on both costs and utility need to be considered to ensure health economic assumptions are up-to-date and closely reflect the case mix of patients.

Why Human Papillomavirus Acute Infections Matter

Most infections by human papillomaviruses (HPVs) are `acute', that is non-persistent. Yet, for HPVs, as for many other oncoviruses, there is a striking gap between our detailed understanding of chronic infections and our limited data on the early stages of infection. Here we argue that studying HPV acute infections is necessary and timely. Focusing on early interactions will help explain why certain infections are cleared while others become chronic or latent. From a molecular perspective, descriptions of immune effectors and pro-inflammatory pathways during the initial stages of infections have the potential to lead to novel treatments or to improved handling algorithms. From a dynamical perspective, adopting concepts from spatial ecology, such as meta-populations or meta-communities, can help explain why HPV acute infections sometimes last for years. Furthermore, cervical cancer screening and vaccines impose novel iatrogenic pressures on HPVs, implying that anticipating any viral evolutionary response remains essential. Finally, hints at the associations between HPV acute infections and fertility deserve further investigation given their high, worldwide prevalence. Overall, understanding asymptomatic and benign infections may be instrumental in reducing HPV virulence.

Clinical effectiveness and cost-effectiveness of interventions for the treatment of anogenital warts: systematic review and economic evaluation

BACKGROUND

Typically occurring on the external genitalia, anogenital warts (AGWs) are benign epithelial skin lesions caused by human papillomavirus infection. AGWs are usually painless but can be unsightly and physically uncomfortable, and affected people might experience psychological distress. The evidence base on the clinical effectiveness and cost-effectiveness of treatments for AGWs is limited.

OBJECTIVES

To systematically review the evidence on the clinical effectiveness of medical and surgical treatments for AGWs and to develop an economic model to estimate the cost-effectiveness of the treatments.

DATA SOURCES

Electronic databases (MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, The Cochrane Library databases and Web of Science) were searched from inception (or January 2000 for Web of Science) to September 2014. Bibliographies of relevant systematic reviews were hand-searched to identify potentially relevant studies. The World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov were searched for ongoing and planned studies.

REVIEW METHODS

A systematic review of the clinical effectiveness literature was carried out according to standard methods and a mixed-treatment comparison (MTC) undertaken. The model implemented for each outcome was that with the lowest deviance information criterion. A de novo economic model was developed to assess cost-effectiveness from the perspective of the UK NHS. The model structure was informed through a systematic review of the economic literature and in consultation with clinical experts. Effectiveness data were obtained from the MTC. Costs were obtained from the literature and standard UK sources.

RESULTS

Of 4232 titles and abstracts screened for inclusion in the review of clinical effectiveness, 60 randomised controlled trials (RCTs) evaluating 19 interventions were included. Analysis by MTC indicated that ablative techniques were typically more effective than topical interventions at completely clearing AGWs at the end of treatment. Podophyllotoxin 0.5% solution (Condyline(®), Takeda Pharmaceutical Company Ltd; Warticon(®) solution, Stiefel Laboratories Ltd) was found to be the most effective topical treatment evaluated. Networks for other outcomes included fewer treatments, which restrict conclusions on the comparative effectiveness of interventions. In total, 84 treatment strategies were assessed using the economic model. Podophyllotoxin 0.5% solution first line followed by carbon dioxide (CO2) laser therapy second line if AGWs did not clear was most likely to be considered a cost-effective use of resources at a willingness to pay of £20,000-30,000 per additional quality-adjusted life-year gained. The result was robust to most sensitivity analyses conducted.

LIMITATIONS

Limited reporting in identified studies of baseline characteristics for the enrolled population generates uncertainty around the comparability of the study populations and therefore the generalisability of the results to clinical practice. Subgroup analyses were planned based on type, number and size of AGWs, all of which are factors thought to influence treatment effect. Lack of data on clinical effectiveness based on these characteristics precluded analysis of the differential effects of treatments in the subgroups of interest. Despite identification of 60 studies, most comparisons in the MTC are informed by only one RCT. Additionally, lack of head-to-head RCTs comparing key treatments, together with minimal reporting of results in some studies, precluded comprehensive analysis of all treatments for AGWs.

CONCLUSIONS

The results generated by the MTC are in agreement with consensus opinion that ablative techniques are clinically more effective at completely clearing AGWs after treatment. However, the evidence base informing the MTC is limited. A head-to-head RCT that evaluates the comparative effectiveness of interventions used in clinical practice would help to discern the potential advantages and disadvantages of the individual treatments. The results of the economic analysis suggest that podophyllotoxin 0.5% solution is likely to represent a cost-effective first-line treatment option. More expensive effective treatments, such as CO2 laser therapy or surgery, may represent cost-effective second-line treatment options. No treatment and podophyllin are unlikely to be considered cost-effective treatment options. There is uncertainty around the cost-effectiveness of treatment with imiquimod, trichloroacetic acid and cryotherapy.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005457.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

A retrospective analysis of the costs and management of genital warts in Italy

BACKGROUND

In Italy the prevalence of genital warts in women (15-64 years) is approximately 0.6% with an incidence of 0.4% per year. Treatments for GW are usually long, with moderate success and high costs. The aim of the study was to evaluate the diagnostic-therapeutic pathway, duration and setting of treatment, costs of episodes of condyloma in a population attending a regional STI clinic in Piedmont.

METHODS

This was a retrospective observational study conducted using medical records of outpatients who first visited the STI Clinic of San Lazzaro Dermatological Hospital in 2008. The patients' medical histories were analysed for episodes that occurred and were cleared in 18 months following the initial visit. Data on screening methods for STIs, type of diagnosis for condyloma, treatment type, treatment setting, and anatomic lesion site were obtained from medical records. The costs were calculated for each episode.

RESULTS

A total of 450 episodes were analysed (297 men,153 women). The most frequently affected anatomic site was the genital area (74%) in both genders. With regard to treatment setting, 78.44% of patients received outpatient treatment at the STI clinic, 4% were treated at home, and 0.22% were hospitalised; 11.11% were treated in multiple settings. The mean number of treatments per episode was 2.03; although many patients received only 1 treatment (n = 207, 46%), exspecially cryotherapy or diathermy coagulation (64.73% versus 28.02% of episodes, respectively). The mean episode duration was 80.74 days. The mean cost (in 2011 euros) for an episode was €158.46 ± 257.77; the mean costs were €79.13 ± 57.40 for diagnosis and €79.33 ± 233.60 for treatment. The mean cost for treatment in a STI-Clinic setting was €111.39 ± 76.72, that for home treatment was €160.88 ± 95.69, and that for hospital care was €2825.94.

CONCLUSIONS

The treatment of and associated costs for genital warts are significant. Several factors affect the cost, and internal STI clinic protocols, such as the 6 month window used to consider a recurrence or new diagnosis, create bias. Nonetheless, our findings how costs similar to those reported in the international literature and should be considered when deciding on which HPV vaccination programs should be provided by the public health system.

Economic and humanistic burden of external genital warts

External genital warts (EGW) are a sexually transmitted infection caused by various strains of human papillomavirus (HPV). Several studies have described the direct and indirect costs of EGW, while others have reported on the burden of EGW in terms of the impact on the quality of life (QOL) of patients. The arrival of a quadrivalent HPV vaccine that protects against both cervical cancer and EGW requires a proper understanding of the impact of vaccines on costs and QOL. Using pre-defined search terms and inclusion/exclusion criteria, we performed a systematic review of the economic and humanistic burden of EGW. The focus of our review was on literature describing the direct and indirect costs of EGW per episode of care (EoC) or per year, as well as the impact of EGW on disease-specific, generic, or preference-based QOL measures. We also reviewed the literature on the national economic burden of EGW from the perspectives of different countries. Other aspects of EGW management that can inform economic modelling studies, such as length of EoC, number of physician visits and indirect costs, were also explored. Our review sheds light on the high economic and humanistic burden of EGW and important differences in the costs between men and women, as well as the differences in health resource utilization and costs across countries. Our study also highlights the dearth of information on the impact of EGW on the QOL and productivity of patients.