Quality of life in restless legs syndrome: A systematic review of clinical trials and a critical review of instruments

Restless legs syndrome (RLS) is a neurological movement disorder characterized by sensory symptoms and motor disturbances. While the underlying cause remains unknown, it is suggested that 20–25% of people with RLS are affected seriously enough to require pharmacological treatment. Dopamine agonists (DAs) are the most common treatment and act by increasing the low levels of dopamine to which RLS is often attributed. A growing literature highlights the debilitating and distressing nature of this condition from the patient's perspective. While sleep problems are most commonly reported, the impact of RLS on quality of life (QOL) is wide ranging, affecting relationships with partners, sex life, family life, social life, leisure activities, friendships, everyday activities, concentration, travel, career/work, sleep, and health.

We conducted a systematic review of clinical trials in which DAs have been evaluated in terms of RLS-specific QOL, i.e. their impact on the QOL of people with RLS, and critically reviewed the development history and measurement properties of RLS-specific QOL instruments.

A systematic search using terms synonymous with RLS, DAs and QOL was conducted using Scopus software, which includes MEDLINE, PsycINFO, EMBASE, and CINAHL. Our search covered publications from 2000 (prior to which RLS-specific QOL measures did not exist) to August 2009. Trials were included in our review if they evaluated DAs for the treatment of adults with RLS and reported evaluation using an RLS-specific QOL measure. We also ran citation searches to identify papers reporting the development history and measurement properties of the identified RLS-specific QOL instruments.

Three measures of RLS-specific QOL have been developed in recent years and are reviewed here: the Restless Legs Syndrome Quality of Life (RLSQOL) questionnaire, the Restless Legs Syndrome Quality of Life Instrument (RLS-QLI), and the Quality of Life Restless Legs Syndrome (QOL-RLS) measure. Critical review indicates that each has limitations (particularly in terms of published developmental history and content validity). Eleven trials of DAs were identified that included assessment of RLS-specific QOL (nine using the RLSQOL and two using the QOL-RLS). In all studies, significant improvements in RLS-specific QOL were observed, although these were mostly short term (12 weeks) and large placebo effects were also noted.

In people with RLS, the use of DAs has been shown to improve RLS-specific QOL. Longer-term, large-scale studies may be needed to confirm these findings and demonstrate statistically significant improvements in RLS-specific QOL at lower doses. Further development of the RLS-specific QOL measures is needed to ensure that the full impact of RLS (and the full benefit of new treatments) on aspects of life identified as important to individuals is captured in future studies.

The suitability of polycystic ovary syndrome-specific questionnaires for measuring the impact of PCOS on quality of life in clinical trials

Objectives: Generic patient-reported outcome (PRO) measures underestimate the impact of polycystic ovary syndrome (PCOS) on quality of life (QoL). The aim of this review was to identify PCOS-specific QoL measures and establish whether their development history and measurement properties support their use in clinical trials.

Methods: A systematic search was conducted using terms synonymous with “PCOS” and “QoL.” Following identification of measures, further searches were undertaken using the questionnaire name and abbreviation to explore its use, development history, and demonstrated measurement properties.

Results: Of 56 abstracts screened, 21 reported using PRO measures. One PCOS-specific QoL measure was identified: the PolyCystic Ovary Syndrome Questionnaire (PCOSQ). Nine papers show that the PCOSQ’s development history is somewhat incomplete, and that it does not have good content validity. The PCOSQ subscales demonstrate acceptable levels of reliability (0.70–0.97) and partial known-groups validity as well as convergent/divergent validity with other PRO instruments. Responsiveness
to change is variable and minimally important differences have not been established.

Conclusions: The PCOSQ is the only condition-specific measure of the impact of PCOS on QoL. Additional research is required to ensure its comprehensiveness, sensitivity, and to guide interpretation prior to including in clinical trials.