Prevalence of new-onset insomnia in patients with obstructive sleep apnoea syndrome treated with nocturnal ventilatory support

INTRODUCTION

New-onset insomnia (NOI) associated with nocturnal ventilatory support (NVS) is becoming a reality in clinical practice; however there is a lack of data about its prevalence. Our aim was to determine the prevalence of NOI in patients with obstructive sleep apnoea syndrome (OSAS) under NVS and its associated risk factors.

MATERIAL AND METHODS

Descriptive cross-sectional study of 80 patients with OSAS under NVS. We compared two groups, with and without NOI, considering demographic characteristics, disease features, and personality. Patients under anxiolytic and/or antidepressant medication, with a weight loss of 10% or greater, and with restless legs symptoms were excluded.

RESULTS

Median age of patients was 60.0 (interquartile range (IQR) 10.0) years; 82.5% were male. Median initial Epworth Sleepiness Scale (ESS) and apnoea-hypopnoea index (AHI) were 12.5 (IQR 9.0) and 44.1 (IQR 22.4)/hr, respectively. The majority of patients (91.3%) were under auto-adjusting positive airway pressure (APAP). Insomnia at baseline was present in 30% of patients (n=24). Prevalence of NOI was 21.4% (12/56). Initial and/or intermediate insomnia were the most frequent subtypes (n=11). We found a statistically significant negative relation between NOI and pressure on 90% night-time (P(90)) (p=0.040).

CONCLUSIONS

OSAS patients under NVS presented a high prevalence of NOI. Patients with NOI presented lower levels of pressure using NVS, compared to the others.

Paradoxical reaction of blood pressure on sleep apnoea patients treated with Positive Airway Pressure

INTRODUCTION

Obstructive Sleep Apnoea Syndrome (OSAS) patients may develop hypertension and Positive Airway Pressure (PAP) is an effective treatment in blood pressure (BP) control.

OBJECTIVES

Analyse a hypertensive OSAS population with unexpected BP rise after PAP usage and verify correlations between BP rise, either with OSAS severity index or nocturnal ventilatory support compliance.

METHODS

Descriptive, retrospective analysis of 30 patients with PAP treated OSA, for one year, on average, and with previous controlled hypertension, who developed a rise in BP, defined as augmentation of > 5 mmHg in systolic (SBP) and/or diastolic BP (DBP), after PAP usage. Co-relational analysis of BP increase, with OSAS severity indexes and therapy compliance, using Pearson coefficient.

RESULTS

Of 508 consecutive patients followed in our Department, treated with nocturnal ventilatory support, 30 evolved with BP rise after initiating treatment (age 58 ± 10.8 years; Apnoea-Hypopnoea Index [AHI], 46.1 ± 18.68). After PAP usage, mean blood pressure (MBP), Systolic BP (SBP) and Diastolic BP (DBP) variation was 16 ± 15 mmHg, 20 ± 25 mmHg and 6 ± 19.4 mmHg, respectively. No patient showed significant BMI increase. Epworth Sleepiness Scale (ESS) value decreased 8.9 ± 5.48 points. MBP, SBP and DBP variations were not correlated with P90/P95, residual AHI, leaks or PAP compliance.

CONCLUSIONS

No specific characteristics were identified in the group who developed a rise in BP with PAP usage. No correlations were found between rises in BP and OSAS severity indexes or PAP compliance. Neither BMI nor variation in wakefulness status explained the rise in BP. Studies relate polymorphisms of β1-adrenoreceptors with different BP responses to ventilatory support. More studies are needed to clarify the cause of this paradoxical response.

Translation of Berlin Questionnaire to Portuguese language and its application in OSA identification in a sleep disordered breathing clinic

BACKGROUND

Berlin Questionnaire (BQ), an English language screening tool for obstructive sleep apnea (OSA) in primary care, has been applied in tertiary settings, with variable results.

AIMS

Development of BQ Portuguese version and evaluation of its utility in a sleep disordered breathing clinic (SDBC).

MATERIAL AND METHODS

BQ was translated using back translation methodology and prospectively applied, previously to cardiorespiratory sleep study, to 95 consecutive subjects, referred to a SDBC, with OSA suspicion. OSA risk assessment was based on responses in 10 items, organized in 3 categories: snoring and witnessed apneas (category 1), daytime sleepiness (category 2), high blood pressure (HBP)/obesity (category 3).

RESULTS

In the studied sample, 67.4 % were males, with a mean age of 51 ± 13 years. Categories 1, 2 and 3 were positive in 91.6, 24.2 and 66.3 %, respectively. BQ identified 68.4 % of the patients as being in the high risk group for OSA and the remaining 31.6 % in the low risk. BQ sensitivity and specificity were 72.1 and 50 %, respectively, for an apnea-hipopnea index (AHI) > 5, 82.6 and 44.8 % for AHI > 15, 88.4 and 39.1 % for AHI > 30. Being in the high risk group for OSA did not influence significantly the probability of having the disease (positive likelihood ratio [LR] between 1.44-1.49). Only the items related to snoring loudness, witnessed apneas and HBP/obesity presented a statistically positive association with AHI, with the model constituted by their association presenting a greater discrimination capability, especially for an AHI > 5 (sensitivity 65.2 %, specificity 80 %, positive LR 3.26).

CONCLUSIONS

The BQ is not an appropriate screening tool for OSA in a SDBC, although snoring loudness, witnessed apneas, HBP/obesity have demonstrated being significant questionnaire elements in this population.

Portuguese Journal of Pulmonology: year-in-review 2009

The Portuguese Journal of Pulmonology is progressively achieving an important status in Portuguese medical literature. The present editors thought it would be an enriching task to revise the main topics published during 2009. The invited members of the Editorial Board covered and commented the most relevant articles and gave us an important picture of the quality of the science it was published in Portuguese Pulmonology.

Successful use of National Cancer Registry data to monitor the effective use of imatinib for treating chronic myeloid leukaemia

Imatinib is a tyrosine kinase inhibitor, which selectively antagonises the BCR-ABL molecular pathway which causes chronic myeloid leukaemia (CML). Imatinib was first approved by the Scottish Medicines Consortium (SMC) in January 2002 with the recommendation that its use be audited. The cost of the drug has major financial implications for health resources.

METHODS

All imatinib usage since its first prescription in Scotland in September 2000 to July 2003 was audited through pharmacy records and through the Scotland Leukaemia Registry (SLR), an existing national registry of patients with CML.

RESULTS

One hundred and four patients in Chronic Phase (CP), 36 in Accelerated Phase (AP) and five in Blast Phase (BP) received imatinib. The median duration of therapy was not reached for CFP 17 months for AFP and two months for BP patients. Major (complete) cytogenetic response rates were 74% (63%) and 38% (24%) respectively for CP and APR Overall survival for all CP patients from the start of imatinib therapy was 94% at one year, 91% at two years and 83% at three years. An audit of the effectiveness of the SLR as an auditing agency, showed complete registration in 95% of cases.

CONCLUSIONS

We believe such data collection should be an important ongoing resource for assessing outcomes in a rare form of leukaemia but one which already has major implications for health economics and will continue to do so given the future development of dual tyrosine kinase inhibitors for imatinib resistant cases.

Stapled haemorrhoidectomy (haemorrhoidopexy) for the treatment of haemorrhoids: a systematic review and economic evaluation

OBJECTIVES

To determine the safety, clinical effectiveness and cost-effectiveness of circular stapled haemorrhoidopexy (SH) for the treatment of haemorrhoids.

DATA SOURCES

Main electronic databases were searched up to July 2006.

REVIEW METHODS

Randomised controlled trials (RCTs) with 20 or more participants that compared SH with any conventional haemorrhoidectomy (CH) technique in people of any age with prolapsing haemorrhoids for whom surgery is considered a relevant option, were used to evaluate clinical effectiveness. An economic model of the surgical treatment of haemorrhoids was developed.

RESULTS

The clinical effectiveness review included 27 RCTs (n = 2279; 1137 SH; 1142 CH). All had some methodological flaws; only two reported recruiting patients with second, third and fourth degree haemorrhoids, and 37% reported using an appropriate method of randomisation and/or allocation concealment. In the early postoperative period 95% of trials reported less pain following SH; by day 21 the pain reported following SH and CH was minimal, with little difference between the two techniques. Significantly fewer patients had unhealed wounds at 6 weeks following SH [odds ratio (OR) 0.08, 95% confidence interval (CI) 0.03 to 0.19, p < 0.001]. Residual prolapse was more common after SH (OR 3.38, 95% CI 1.00 to 11.47, p = 0.05, nine RCTs, results of a sensitivity analysis). There was no difference between SH and CH in the incidence of bleeding or postoperative complications. SH resulted in shorter operating times, hospital stay, time to first bowel movement and return to normal activity. In the short term (between 6 weeks and a year) prolapse was more common after SH (OR 4.68, 95% CI 1.11 to 19.71, p = 0.04, six RCTs). There was no difference in the number of patients complaining of pain between SH and CH. In the long term (1 year and over), there was a significantly higher rate of prolapse after SH (OR 4.34, 95% CI 1.67 to 11.28, p = 0.003, 12 RCTs). There was no difference in the number of patients experiencing pain, or the incidence of bleeding, between SH and CH. There was no difference in the total number of reinterventions, or reinterventions for pain, bleeding or complications, between SH and CH. Significantly more reinterventions were undertaken after SH for prolapse at 12 months or longer (OR 6.78, 95% CI 2.00 to 23.00, p = 0.002, six RCTs). Overall, there was no statistically significant difference in the rate of complications between SH and CH. In the economic assessment it was found that, on average, CH dominated SH. However, CH and SH had very similar costs and quality-adjusted life-years (QALYs). On average, the difference in costs between the procedures was 19 pounds and the difference in QALY was -0.001, favouring CH, over 3 years. In terms of QALYs, the superior quality of life due to lower pain levels in the early postoperative period with SH was offset by the higher rate of symptoms over the follow-up period, compared with CH. The results are very sensitive to modelling assumptions, particularly the valuation of utility in the early postoperative period. The probabilistic sensitivity analysis showed that, at a threshold incremental cost-effectiveness ratio of 20,000-30,000 pounds per QALY, SH had a 45% probability of being cost-effective.

CONCLUSIONS

SH was associated with less pain in the immediate postoperative period, but a higher rate of residual prolapse, prolapse in the longer term and reintervention for prolapse. There was no clear difference in the rate or type of complications associated with the two techniques and the absolute and relative rates of recurrence and reintervention for both are still uncertain. CH and SH had very similar costs and QALYs, the cost of the staple gun being offset by savings in hospital stay. Should the price of the gun change, the conclusions of the economic analysis may also change. Some training may be required in the use of the staple gun; this is not expected to have major resource implications. Given the currently available clinical evidence and the results of the economic analysis, the decision as to whether SH or CH is conducted could primarily be based on the priorities and preferences of the patient and surgeon. An adequately powered, good-quality RCT is required, comparing SH with CH, recruiting patients with second, third and fourth degree haemorrhoids, and having a minimum follow-up period of 5 years to ensure an adequate evaluation of the reintervention rate. Other areas for research are the effectiveness of SH in patients with fourth degree haemorrhoids and patients with co-morbid conditions, the reintervention rates for all treatments for haemorrhoids, utilities of patients up to 6 months postoperatively, the trade-offs of patients for short-term pain versus long-term outcomes, and the ability of SH to reduce hospital stays in a real practice setting.

A systematic review of the effectiveness and cost-effectiveness of different models of community-based respite care for frail older people and their carers

OBJECTIVES

To review the evidence for different models of community-based respite care for frail older people and their carers, where the participant group included older people with frailty, disability, cancer or dementia. Where data permitted, subgroups of carers and care recipients, for whom respite care is particularly effective or cost-effective, were to be identified.

DATA SOURCES

Major databases were searched from 1980 to March 2005. Ongoing and recently completed research databases were searched in July 2005.

REVIEW METHODS

Data from relevant studies were extracted and quality assessed. The possible effects of study quality on the effectiveness data and review findings were discussed. Where sufficient clinically and statistically similar data were available, data were pooled using appropriate statistical techniques.

RESULTS

Twenty-two primary studies were included. Most of the evidence came from North America, with a minority of effectiveness and economic studies based in the UK. Types of service studied included day care, host family, in-home, institutional and video respite. Effectiveness evidence suggests that the consequences of respite upon carers and care recipients are generally small, with better controlled studies finding modest benefits only for certain subgroups. However, many studies report high levels of carer satisfaction. No reliable evidence was found that respite can delay entry to residential care or that respite adversely affects care recipients. Randomisation validity in the included randomised studies was sometimes unclear. Studies reported many different outcome measures, and all of the quasi-experimental and uncontrolled studies had methodological weaknesses. The descriptions of the studies did not provide sufficient detail of the methods of data collection or analysis, and the studies failed to describe adequately the groups of study participants. In some studies, only evidence to support respite care services was presented, rather than a balanced view of the services. Only five economic evaluations of respite care services were found, all of which compared day care with usual care and only one study was undertaken in the UK. Day care tended to be associated with higher costs and either similar or a slight increase in benefits, relative to usual care. The economic evaluations were based on two randomised and three quasi-experimental studies, all of which were included in the effectiveness analysis. The majority of studies assessed health and social service use and cost, but inadequate reporting limits the potential for exploring applicability to the UK setting. No study included generic health-related quality of life measures, making cost-effectiveness comparisons with other healthcare programmes difficult. One study used sensitivity analysis to explore the robustness of the findings.

CONCLUSIONS

The literature review provides some evidence that respite for carers of frail elderly people may have a small positive effect upon carers in terms of burden and mental or physical health. Carers were generally very satisfied with respite. No reliable evidence was found that respite either benefits or adversely affects care recipients, or that it delays entry to residential care. Economic evidence suggests that day care is at least as costly as usual care. Pilot studies are needed to inform full-scale studies of respite in the UK.

Estimating the long-term impact of a prophylactic human papillomavirus 16/18 vaccine on the burden of cervical cancer in the UK

To predict the public health impact on cervical disease by introducing human papillomavirus (HPV) vaccination in the United Kingdom, we developed a mathematical model that can be used to reflect the impact of vaccination in different countries with existing screening programmes. Its use is discussed in the context of the United Kingdom. The model was calibrated with published data. The impact of vaccination on cervical cancer and deaths, precancerous lesions and screening outcomes were estimated for a vaccinated cohort of 12-year-old girls, among which it is estimated that there would be a reduction of 66% in the prevalence of high-grade precancerous lesions and a 76% reduction in cervical cancer deaths. Estimates for various other measures of the population effects of vaccination are also presented. We concluded that it is feasible to forecast the potential effects of HPV vaccination in the context of an existing national screening programme. Results suggest a sizable reduction in the incidence of cervical cancer and related deaths. Areas for future research include investigation of the beneficial effects of HPV vaccination on infection transmission and epidemic dynamics, as well as HPV-related neoplasms in other sites.

A systematic review and economic model of the effectiveness and cost-effectiveness of methylphenidate, dexamfetamine and atomoxetine for the treatment of attention deficit hyperactivity disorder in children and adolescents

OBJECTIVES

To assess the clinical and cost-effectiveness of oral methylphenidate hydrochloride (MPH), dexamfetaminesulphate (DEX) and atomoxetine (ATX) in children and adolescents (<18 years of age) diagnosed with attention deficit hyperactivity disorder (ADHD) (including hyperkinetic disorder).

DATA SOURCES

Electronic databases covering 1999--July 2004 for MPH, 1997--July 2004 for DEX and 1981--July 2004 for ATX.

REVIEW METHODS

Selected studies were assessed using modified criteria based on CRD Report No. 4. Clinical effectiveness data were reported separately for each drug and by the type of comparison. Data for MPH were also analysed separately based on whether it was administered as an immediate release (IR) or extended release (ER) formulation. For all drugs, the data were examined by dose. Data for the core outcomes of hyperactivity (using any scale), Clinical Global Impression [as a proxy of quality of life (QoL)] and adverse events were reported. For crossover studies, the mean and standard deviation (SD) for each outcome were data extracted for end of trial data (i.e. baseline data were not considered). For parallel studies, change scores were reported where given, otherwise means and SDs were presented for end of trial data. In addition, mean differences with 95% confidence intervals were calculated for each study. For adverse events, self-ratings were reported when used, otherwise, parent reports were utilised. Percentages of participants reporting adverse events were used to calculate numbers of events in each treatment arm. All the clinical effectiveness data and economic evaluations (including accompanying models) included in the company submissions were assessed. A new model was developed to assess the cost-effectiveness of the alternative treatments in terms of cost per quality-adjusted life-year. To achieve this, a mixed treatment comparison model was used to estimate the differential mean response rates. Monte Carlo simulation was used to reflect uncertainty in the cost-effectiveness results.

RESULTS

In total, 65 papers met the inclusion criteria. The results suggest that MPH and DEX are effective at reducing hyperactivity and improving QoL (as determined by Clinical Global Impression) in children, although the reliability of the MPH study results is not known and there were only a small number of DEX studies. There was consistent evidence that ATX was superior to placebo for hyperactivity and Clinical Global Impression. Studies on ATX more often reported the study methodology well, and the results were likely to be reliable. Very few studies made direct head-to-head comparisons between the drugs or examined a non-drug intervention in combination with MPH, DEX or ATX. Adequate and informative data regarding the potential adverse effects of the drugs were also lacking. The results of the economic evaluation clearly identified an optimal treatment strategy of DEX first-line, followed by IR-MPH for treatment failures, followed by ATX for repeat treatment failures. Where DEX is unsuitable as a first-line therapy, the optimal strategy is IR-MPH first-line, followed by DEX and then ATX. For patients contraindicated to stimulants, ATX is preferred to no treatment. For patients in whom a midday dose of medication is unworkable, ER-MPH is preferred to ATX, and ER-MPH12 appears more cost-effective than ER-MPH8. As identified in the clinical effectiveness review, the reporting of studies was poor, therefore this should be borne in mind when interpreting the model results.

CONCLUSIONS

Drug therapy seems to be superior to no drug therapy, no significant differences between the various drugs in terms of efficacy or side effects were found, mainly owing to lack of evidence, and the additional benefits from behavioural therapy (in combination with drug therapy) are uncertain. Given the lack of evidence for any differences in effectiveness between the drugs, the economic model tended to be driven by drug costs, which differed considerably. Future trials examining MPH, DEX and ATX should include the assessment of tolerability and safety as a priority. Longer term follow-up of individuals participating in trials could further inform policy makers and health professionals. Such data could potentially distinguish between these drugs in a clinically useful way. In addition, research examining whether somatic complaints are actually related to drug treatment or to the disorder itself would be informative.

Pharmacoeconomics: friend or foe?

The financial constraints faced by most health systems today make it necessary for manufacturers of new, expensive drugs to demonstrate value for money. This paper describes the different types of economic evaluation; the increasing use of these analysis in decision making; their application to new drugs in the field of in rheumatoid arthritis; and the pros and cons of pharmacoeconomics studies from the perspective of the patients, the physicians, and the general population.

Clinical effectiveness, tolerability and cost-effectiveness of newer drugs for epilepsy in adults: a systematic review and economic evaluation

OBJECTIVES

To examine the clinical effectiveness, tolerability and cost-effectiveness of gabapentin (GBP), lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), tiagabine (TGB), topiramate (TPM) and vigabatrin (VGB) for epilepsy in adults.

DATA SOURCES

Electronic databases. Internet resources. Pharmaceutical company submissions.

REVIEW METHODS

Selected studies were screened and quality assessed. Separate analyses assessed clinical effectiveness, serious, rare and long-term adverse events and cost-effectiveness. An integrated economic analysis incorporating information on costs and effects of newer and older antiepileptic drugs (AEDs) was performed to give direct comparisons of long-term costs and benefits.

RESULTS

A total of 212 studies were included in the review. All included systematic reviews were Cochrane reviews and of good quality. The quality of randomised controlled trials (RCTs) was variable. Assessment was hampered by poor reporting of methods of randomisation, allocation concealment and blinding. Few of the non-randomised studies were of good quality. The main weakness of the economic evaluations was inappropriate use of the cost-minimisation design. The included systematic reviews reported that newer AEDs were effective as adjunctive therapy compared to placebo. For newer versus older drugs, data were available for all three monotherapy AEDs, although data for OXC and TPM were limited. There was limited, poor-quality evidence of a significant improvement in cognitive function with LTG and OXC compared with older AEDs. However, there were no consistent statistically significant differences in other clinical outcomes, including proportion of seizure-free patients. No studies assessed effectiveness of AEDs in people with intellectual disabilities or in pregnant women. There was very little evidence to assess the effectiveness of AEDs in the elderly; no significant differences were found between LTG and carbamazepine monotherapy. Sixty-seven RCTs compared adjunctive therapy with placebo, older AEDs or other newer AEDs. For newer AEDs versus placebo, a trend was observed in favour of newer drugs, and there was evidence of statistically significant differences in proportion of responders favouring newer drugs. However, it was not possible to assess long-term effectiveness. Most trials were conducted in patients with partial seizures. For newer AEDs versus older drugs, there was no evidence to assess the effectiveness of LEV, LTG or OXC, and evidence for other newer drugs was limited to single studies. Trials only included patients with partial seizures and follow-up was relatively short. There was no evidence to assess effectiveness of adjunctive LEV, OXC or TPM versus other newer drugs, and there were no time to event or cognitive data. No studies assessed the effectiveness of adjunctive AEDs in the elderly or pregnant women. There was some evidence from one study (GBP versus LTG) that both drugs have some beneficial effect on behaviour in people with learning disabilities. Eighty RCTs reported the incidence of adverse events. There was no consistent or convincing evidence to draw any conclusions concerning relative safety and tolerability of newer AEDs compared with each other, older AEDs or placebo. The integrated economic analysis for monotherapy for newly diagnosed patients with partial seizures showed that older AEDs were more likely to be cost-effective, although there was considerable uncertainty in these results. The integrated analysis suggested that newer AEDs used as adjunctive therapy for refractory patients with partial seizures were more effective and more costly than continuing with existing treatment alone. Combination therapy, involving new AEDs, may be cost-effective at a threshold willingness to pay per quality-adjusted life year (QALY) greater than 20,000 pounds, depending on patients' previous treatment history. There was, again, considerable uncertainty in these results. There were few data available to determine effectiveness of treatments for patients with generalised seizures. LTG and VPA showed similar health benefits when used as monotherapy. VPA was less costly and was likely to be cost-effective. The analysis indicated that TPM might be cost-effective when used as an adjunctive therapy, with an estimated incremental cost-effectiveness ratio of 34,500 pounds compared with continuing current treatment alone.

CONCLUSIONS

There was little good-quality evidence from clinical trials to support the use of newer monotherapy or adjunctive therapy AEDs over older drugs, or to support the use of one newer AED in preference to another. In general, data relating to clinical effectiveness, safety and tolerability failed to demonstrate consistent and statistically significant differences between the drugs. The exception was comparisons between newer adjunctive AEDs and placebo, where significant differences favoured newer AEDs. However, trials often had relatively short-term treatment durations and often failed to limit recruitment to either partial or generalised onset seizures, thus limiting the applicability of the data. Newer AEDs, used as monotherapy, may be cost-effective for the treatment of patients who have experienced adverse events with older AEDs, who have failed to respond to the older drugs, or where such drugs are contraindicated. The integrated economic analysis also suggested that newer AEDs used as adjunctive therapy may be cost-effective compared with the continuing current treatment alone given a QALY of about 20,000 pounds. There is a need for more direct comparisons of the different AEDs within clinical trials, considering different treatment sequences within both monotherapy and adjunctive therapy. Length of follow-up also needs to be considered. Trials are needed that recruit patients with either partial or generalised seizures; that investigate effectiveness and cost-effectiveness in patients with generalised onset seizures and that investigate effectiveness in specific populations of epilepsy patients, as well as studies evaluating cognitive outcomes to use more stringent testing protocols and to adopt a more consistent approach in assessing outcomes. Further research is also required to assess the quality of life within trials of epilepsy therapy using preference-based measures of outcomes that generate cost-effectiveness data. Future RCTs should use CONSORT guidelines; and observational data to provide information on the use of AEDs in actual practice, including details of treatment sequences and doses.

Cost effectiveness of photodynamic therapy with verteporfin for age related macular degeneration: the UK case

AIM

To estimate the potential cost effectiveness of photodynamic therapy (PDT) with verteporfin in the UK setting.

METHODS

Using data from a variety of sources a Markov model was built to produce estimates of the cost effectiveness (incremental cost per quality adjusted life year (QALY) and incremental cost per vision year gained) of PDT for two cohorts of patients (one with starting visual acuity (VA) of 20/40 and one at 20/100) with predominantly classic choroidal neovascular disease over a 2 year and 5 year time horizon. A government perspective and a treatment cost only perspective were considered. Probabilistic and one way sensitivity analyses were undertaken.

RESULTS

From the government perspective, over the 2 year period, the expected incremental cost effectiveness ratios range from 286 000 (starting VA 20/100) to 76 000 UK pounds (starting VA 20/40) per QALY gained and from 14 000 (20/100) to 34 000 UK pounds (20/40) per vision year gained. A 5 year perspective yields incremental ratios less than 5000 UK pounds for vision years gained and from 9000 (20/40) to 30 000 UK pounds (20/100) for QALYs gained. Without societal or NHS cost offsets included, the 2 year incremental cost per vision year gained ranges from 20 000 (20/100) to 40 000 UK pounds (20/40), and the 2 year incremental cost per QALY gained ranges from 412 000 (20/100) to 90 000 UK pounds (20/40). The 5 year time frame shows expected costs of 7000 (20/40) to 10 000 UK pounds (20/100) per vision year gained and from 38 000 (20/40) to 69 000 UK pounds (20/100) per QALY gained.

CONCLUSION

This evaluation suggests that early treatment (that is, treating eyes at less severe stages of disease) with PDT leads to increased efficiency. When considering only the cost of therapy, treating people at lower levels of visual acuity would probably not be considered cost effective. However, a broad perspective that incorporates other NHS treatment costs and social care costs suggests that over a long period of time, PDT may yield reasonable value for money.