BackgroundDuchenne Muscular Dystrophy (DMD) is a rapidly progressive, lethal neuromuscular disorder, present from birth, which occurs almost exclusively in males. We have reviewed contemporary evidence of burden, epidemiology, illness costs and treatment patterns of DMD.This systematic review adhered to published methods with information also sought from the web and contacting registries. Searches were carried out from 2005 to June 2015. The population of interest was individuals with clearly defined DMD or their carers.ResultsNine thousand eight hundred fifty titles were retrieved from searches. Fifty-eight studies were reviewed with three assessed as high, 33 as medium and 22 as low quality. We found two studies reporting birth and four reporting point prevalence, three reporting mortality, 41 reporting severity and/or progression, 18 reporting treatment patterns, 12 reporting quality of life, two reporting utility measures, three reporting costs of illness and three treatment guidelines.Birth prevalence ranged from 15.9 to 19.5 per 100,000 live births. Point prevalence per 100,000 males was for France, USA, UK and Canada, 10.9, 1.9, 2.2 and 6.1 respectively. A study of adult DMD patients at a centre in France found median survival for those born between 1970 and 1994 was 40.95 years compared to 25.77 years for those born between 1955 and 1969. Loss of ambulation occurred at a median age of 12 and ventilation starts at about 20 years. There was international variation in use of corticosteroids, scoliosis surgery, ventilation and physiotherapy. The economic cost of DMD climbs dramatically with disease progression – rising as much as 5.7 fold from the early ambulatory phase to the non-ambulatory phase in Germany.ConclusionsThis is the first systematic review of treatment, progression, severity and quality of life in DMD. It also provides the most recent description of the burden, epidemiology, illness costs and treatment patterns in DMD. There are evidence gaps, particularly in prevalence and mortality. People with DMD seem to be living longer, possibly due to corticosteroid use, cardiac medical management and ventilation. Future research should incorporate registry data to improve comparability across time and between countries and to investigate the quality of life impact as the condition progresses.Electronic supplementary materialThe online version of this article (doi:10.1186/s13023-017-0631-3) contains supplementary material, which is available to authorized users.

The objective of this study was to assess recent data on the prevalence of chronic pain as part of chronic diseases; the prevalence of chronic pain as a chronic condition in its own right; the costs attributed to chronic pain; and the European Union (EU) policies to addressing chronic pain. Recent literature was reviewed for data on the prevalence and cost implications of chronic pain in the EU. Following on from an earlier systematic review, 8 databases were searched for prevalence and 10 for cost information from 2009 to 2011 and relevant EU organizations were contacted. Ten cost and 29 prevalence studies were included from the 142 full papers screened. The general adult population reported an average chronic pain prevalence of 27%, which was similar to those for common chronic conditions. Fibromyalgia had the highest unemployment rate (6%; Rivera et al., Clin Exp Rheumatol. 2009;27[Suppl 56]:S39-S45) claims for incapacity benefit (up to 29.9%; Sicras-Mainar et al., Arthritis Res Ther. 2009;11:R54), and greatest number of days of absence from work (Rivera et al., Clin Exp Rheumatol. 2009;27[Suppl 56]:S39-S45). Chronic pain is common and the total population cost is high. Despite its high impact, chronic pain as a condition seems to have had little specific policy response. However, there does appear to be sufficient evidence to at least make addressing chronic pain a high priority alongside other chronic diseases as well as to conduct more research, particularly regarding cost.

BackgroundMorquio A (MPS IVA) is a rare disease characterised by a deficiency of N-acetylgalactosamine-6 sulfatase (GALNS) and presenting with short stature, abnormal gait, cervical spine instability and shortened lifespan.PurposeTo prepare a systematic review of the prevalence of Morquio A in multiple countries and suggest recommendations for reporting rare diseases.MethodsMedline, Medline In-Process, Medline Daily Update, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database and PROSPERO were searched from inception to October 2013 to identify relevant information on the epidemiology of Morquio A. Forty Patient Organisation Representatives (POR) and Key Opinion Leaders (KOL) across 24 countries were contacted for data. Observational studies were included and case reports were excluded. Searches were performed without date or language restriction. Two researchers independently screened and extracted data. Quality of study reporting was assessed using a checklist adapted from STROBE (STrengthening the Reporting of OBservational studies in Epidemiology). Point or birth prevalence was stratified according to diagnostic method and discussed narratively.ResultsIn total 9,074 records were retrieved from searching and 25 studies were included for data extraction. Twenty out of 40 KOL and POR responded (50%) and 9 provided data (23%). Point prevalence of Morquio A was 1 per 926,000 in Australia, 1 per 1,872,000 in Malaysia and 1 per 599,000 in UK and Morquio (unclassified) was 1 per 323, 000 in Denmark. Birth prevalence of Morquio A (using recommended diagnostic methods) ranged from 1 per 71,000 in UAE to 1 per 500,000 in Japan. All results were compromised by poor study reporting and internal validity.ConclusionsThe review highlighted that there is a misunderstanding of the definitions for prevalence and incidence in the field; that studies were poorly reported (diagnostic methods and patient characteristics) and that no suitable quality assessment tool exists. Overestimation and underestimation of prevalence data can occur. Bespoke reporting guidelines and a quality assessment tool specifically for prevalence of rare diseases are recommended.Electronic supplementary materialThe online version of this article (doi:10.1186/s13023-014-0173-x) contains supplementary material, which is available to authorized users.

There is strong evidence of a correlation between pain severity and QoL. There is some evidence that treatment in chronic pain patients can reduce pain and simultaneously improve QoL. Prevention and treatment of chronic pain may be of significant help in reaching the aim to increase the healthy lifespan.