Population ageing challenges health care systems due to the high prevalence and impact of multimorbidity in older adults. However, little is known about how chronic conditions present in certain multimorbidity patterns, which could have great impact on public health at several levels. The aim of our study was to identify and describe multimorbidity patterns in low-, middle-, and high-income countries. We analyzed data from the Collaborative Research on Ageing in Europe project (Finland, Poland, and Spain) and the World Health Organization’s Study on Global Ageing and Adult Health (China, Ghana, India, Mexico, Russia, and South Africa). These cross-sectional studies obtained data from 41,909 noninstitutionalized adults older than 50 years. Exploratory factor analysis was performed to detect multimorbidity patterns. Additional adjusted binary logistic regressions were performed to identify associations between sociodemographic factors and multimorbidity. Overall multimorbidity prevalence was high across countries. Hypertension, cataract, and arthritis were the most prevalent comorbid conditions. Two or three multimorbidity patterns were found per country. Several patterns were identified across several countries: “cardio-respiratory” (angina, asthma, and chronic obstructive pulmonary disease), “metabolic” (diabetes, obesity, and hypertension), and “mental-articular” (arthritis and depression). A high prevalence of multimorbidity occurs in older adults across countries, with low- and middle-income countries gradually approaching the figures of richer countries. Certain multimorbidity patterns are present in several countries, which suggest that common underlying etiopathogenic factors may play a role. Deeper understanding of these patterns may lead to the development of preventive actions to diminish their prevalence and also give rise to new, comprehensive approaches for the management of these co-occurring conditions.

Background: The WHODAS-2 is a disability assessment instrument based on the conceptual framework of the International Classification of Functioning, Disability, and Health (ICF). It provides a global measure of disability and 7 domain-specific scores. The aim of this study was to assess WHODAS-2 conceptual model and metric properties in a set of chronic and prevalent clinical conditions accounting for a wide scope of disability in Europe. Methods: 1,119 patients with one of 13 chronic conditions were recruited in 7 European centres. Participants were clinically evaluated and administered the WHODAS-2 and the SF-36 at baseline, 6 weeks and 3 months of follow-up. The latent structure was explored and confirmed by factor analysis (FA). Reliability was assessed in terms of internal consistency (Cronbach's alpha) and reproducibility (intra-class correlation coefficients, ICC). Construct validity was evaluated by correlating the WHODAS-2 and SF-36 domains, and comparing known groups based on the clinical-severity and work status. Effect size (ES) coefficient was used to assess responsiveness. To assess reproducibility and responsiveness, subsamples of stable (at 6 weeks) and improved (after 3 moths) patients were defined, respectively, according to changes in their clinical-severity. Results: The satisfactory FA goodness of fit indexes confirmed a second order factor structure with 7 dimensions, and a global score for the WHODAS-2. Cronbach's alpha ranged from 0.77 (self care) to 0.98 (life activities: work or school), and the ICC was lower, but achieved the recommended standard of 0.7 for four domains. Correlations between global WHODAS-2 score and the different domains of the SF-36 ranged from -0.29 to -0.65. Most of the WHODAS-2 scores showed statistically significant differences among clinical-severity groups for all pathologies, and between working patients and those not working due to ill health (p < 0.001). Among the subsample of patients who had improved, responsiveness coefficients were small to moderate (ES = 0.3-0.7), but higher than those of the SF-36. Conclusions: The latent structure originally designed by WHODAS-2 developers has been confirmed for the first time, and it has shown good metric properties in clinic and rehabilitation samples. Therefore, considerable support is provided to the WHODAS-2 utilization as an international instrument to measure disability based on the ICF model.

This overview of the published epidemiological evidence of migraine helps to identify the size of the public–health problem that migraine represents. It also highlights the need for further epidemiological studies in many parts of the world to gain full understanding of the scale of clinical, economic and humanistic burdens attributable to it. This paper presents some of the work on migraine undertaken by the World Health Organization (WHO) in the Global Burden of Disease study conducted in 2000 and reported in the World Health Report 2001. Migraine was not included in the first Global Burden of Disease 1990. The paper also discussed the measurement of disability attributable to headache disorders using WHO ICF Classification. Using disabilityadjusted life years (DALYs) as a summary measure of population health (which adds disability to mortality), WHO have shown that mental and neurological disorders collectively account for 30.8% of all years of healthy life lost to disability (YLDs) whilst migraine, one amongst these, alone accounts for 1.4% and is in the top 20 causes of disability worldwide. This information is combined with the increasingly widely accepted belief that disability and functioning are relevant parameters for monitoring the health of nations and that there is an increasing need to measure them. WHO's Classification of Functioning, Disability and Health (ICF) provides a model of human functioning and disability, as well as a classification system, that allows us to highlight and measure all dimensions of disability. ICF applied to headache disorders allows comparability with other health conditions as well as evaluation of the role of the environment as a cause of disability amongst people with headache. Migraine causes a large propotion of the non–fatal disease–related burden worldwide.Our kowledge of headache related burden is incomplete and it is necessary to add to it epidemiological studies in many parts of the world and to combine this with measurements of disability using both DALYs and WHO ‘s ICF Classification. The work described here has been the base for the Global Campaign against Headache disorders: "Lifting the Burden", launched in 2004 jointly by WHO, IHS (International Headache Society), WHA (World Headache Alliance) and EHF (European Headache Federation).

The International Classification of Functioning Disability and Health (ICF) was approved in 2001 and, since then, several studies reported the increased interest about its use in different sectors. A recent overview that summarizes its applications is lacking. This study aims to provide an updated overview about 20 years of ICF application through an international online questionnaire, developed by the byline authors, and sent to each World Health Organization Collaborating Centers of the Family of International Classifications (WHO-FIC CCs). Data was collected during October 2020 and December 2021 and descriptive content analyses were used to report main results. Results show how, in most of the respondent countries represented by WHO-FIC CCs, ICF was mainly used in clinical practice, policy development and social policy, and in education areas. Despite its applications in different sectors, ICF use is not mandatory in most countries but, where used, it provides a biopsychosocial framework for policy development in health, functioning and disability. The study provides information about the needs related to ICF applications, that can be useful to organize targeted intervention plans. Furthermore, this survey methodology can be re-proposed periodically to monitor the use of the ICF in the future.

Background: The aim of this study was to evaluate the factors associated with low skeletal muscle mass (SMM), sarcopenia, and sarcopenic obesity using nationally representative samples of people aged ≥65 years from diverse geographical regions of the world.Methods: Data were available for 18 363 people aged ≥65 years who participated in the Collaborative Research on Ageing in Europe survey conducted in Finland, Poland, and Spain, and the World Health Organization Study on global AGEing and adult health survey conducted in China, Ghana, India, Mexico, Russia, and South Africa, between 2007 and 2012. A skeletal muscle mass index (SMI) was created to reflect SMM. SMM, SMI, and percent body fat (%BF) were calculated with specific indirect population formulas. These estimates were based on age, sex, weight, height, and race. Sarcopenia and sarcopenic obesity were defined with specific cut‐offs.Results: The prevalence of sarcopenia ranged from 12.6% (Poland) to 17.5% (India), and that of sarcopenic obesity ranged from 1.3% (India) to 11.0% (Spain). Higher %BF was associated with lower SMM in all countries, and with sarcopenia in five countries (p < 0.001). Compared to high levels of physical activity, low levels were related with higher odds for sarcopenia [OR 1.36 (95%CI 1.11–1.67)] and sarcopenic obesity [OR 1.80 (95%CI 1.23–2.64)] in the overall sample. Also, a dose‐dependent association between higher numbers of chronic diseases and sarcopenic obesity was observed.Conclusions: Physical activity and body composition changes such as high %BF are key factors for the prevention of sarcopenia syndrome.