Burden of post-herpetic neuralgia in a sample of UK residents aged 50 years or older: findings from the zoster quality of life (ZQOL) study

Background: Post-herpetic neuralgia (PHN) is the most common complication of herpes zoster (shingles). As a chronic condition, PHN can have a substantial adverse impact on patients' lives. However, UK-specific data concerning the burden of PHN on individual patients, healthcare systems and wider society, are lacking. As the first UK-wide cross-sectional study of its kind, The Zoster Quality of Life (ZQOL) study was designed to address these concerns. Methods: Patients (n = 152) with a confirmed diagnosis of PHN (defined as pain persisting >= 3 months following rash onset) and aged >= 50 years were recruited from primary and secondary/tertiary care centres throughout the UK. All patients completed validated questionnaires, including the Zoster Brief Pain Inventory (ZBPI), the Medical Outcomes Study Short-Form 36 (SF-36), the EuroQol-5 Dimensions (EQ-5D) and the Treatment Satisfaction with Medication (TSQM) questionnaire. Where available, mean patient population scores on these questionnaires were compared to scores derived from age-matched normative samples to quantify the burden associated with PHN. Results: Despite numerous consultations with healthcare professionals and receiving multiple medications for the management of their PHN, the majority of patients reported being in pain 'most of the time' or 'all of the time'. A total of 59.9% (n = 91) of all PHN patients reported pain in the preceding 24 hours to assessment at levels (ZBPI worst pain >= 5) typically considered to have a significant impact on Health Related Quality of Life (HRQoL). Accordingly, scores for SF-36 and EQ-5D indicated significant deficits in HRQoL among PHN patients compared to age-matched norms (p < 0.05) and patients reported being dissatisfied with the perceived efficacy of therapies received for the management of PHN. Increased pain severity was observed among older participants and higher levels of pain severity were associated with greater HRQoL deficits. Conclusions: The inadequate relief provided by PHN therapies available in the UK is associated with a significant burden among PHN patients in terms of pain severity and deficits in HRQoL which may persist for years. Therefore, alternative means such as prevention of shingles and PHN, are essential for reducing the impact on individual patients, healthcare systems and society as a whole.