title: The impact of multimorbidity on adult physical and mental health in low- and middle-income countries: what does the study on global ageing and adult health (SAGE) reveal?
abstract: BACKGROUND
  Chronic diseases contribute a large share of disease burden in low- and middle-income countries (LMICs). Chronic diseases have a tendency to occur simultaneously and where there are two or more such conditions, this is termed as 'multimorbidity'. Multimorbidity is associated with adverse health outcomes, but limited research has been undertaken in LMICs. Therefore, this study examines the prevalence and correlates of multimorbidity as well as the associations between multimorbidity and self-rated health, activities of daily living (ADLs), quality of life, and depression across six LMICs.
  
  
  METHODS
  Data was obtained from the WHO's Study on global AGEing and adult health (SAGE) Wave-1 (2007/10). This was a cross-sectional population based survey performed in LMICs, namely China, Ghana, India, Mexico, Russia, and South Africa, including 42,236 adults aged 18 years and older. Multimorbidity was measured as the simultaneous presence of two or more of eight chronic conditions including angina pectoris, arthritis, asthma, chronic lung disease, diabetes mellitus, hypertension, stroke, and vision impairment. Associations with four health outcomes were examined, namely ADL limitation, self-rated health, depression, and a quality of life index. Random-intercept multilevel regression models were used on pooled data from the six countries.
  
  
  RESULTS
  The prevalence of morbidity and multimorbidity was 54.2 % and 21.9 %, respectively, in the pooled sample of six countries. Russia had the highest prevalence of multimorbidity (34.7 %) whereas China had the lowest (20.3 %). The likelihood of multimorbidity was higher in older age groups and was lower in those with higher socioeconomic status. In the pooled sample, the prevalence of 1+ ADL limitation was 14 %, depression 5.7 %, self-rated poor health 11.6 %, and mean quality of life score was 54.4. Substantial cross-country variations were seen in the four health outcome measures. The prevalence of 1+ ADL limitation, poor self-rated health, and depression increased whereas quality of life declined markedly with an increase in number of diseases.
  
  
  CONCLUSIONS
  Findings highlight the challenge of multimorbidity in LMICs, particularly among the lower socioeconomic groups, and the pressing need for reorientation of health care resources considering the distribution of multimorbidity and its adverse effect on health outcomes.
authors.affiliation: International Institute for Population Sciences, Mumbai, India. arokiasamy_peria@yahoo.com.
authors.forename: Perianayagam
authors.initials: P
authors.lastname: Arokiasamy
authors.affiliation: International Institute for Population Sciences, Mumbai, India. uttamacharya.iips@gmail.com.
authors.forename: Uttamacharya
authors.initials: U
authors.lastname: Uttamacharya
authors.affiliation: International Institute for Population Sciences, Mumbai, India. kshipraaa@googlemail.com.
authors.forename: Kshipra
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authors.lastname: Jain
authors.affiliation: Department of Community Health, University of Ghana, Accra, Ghana. biritwum@africaonline.com.gh.
authors.forename: Richard Berko
authors.initials: RB
authors.lastname: Biritwum
authors.affiliation: Department of Community Health, University of Ghana, Accra, Ghana. aeyawson@yahoo.com.
authors.forename: Alfred Edwin
authors.initials: AE
authors.lastname: Yawson
authors.affiliation: Shanghai Municipal Center for Disease Control and Prevention (CDC), Shanghai, China. wufan@scdc.sh.cn.
authors.forename: Fan
authors.initials: F
authors.lastname: Wu
authors.affiliation: Shanghai Municipal Center for Disease Control and Prevention (CDC), Shanghai, China. guoyanfei@scdc.sh.cn.
authors.forename: Yanfei
authors.initials: Y
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authors.affiliation: Russian Academy of Medical Sciences (RAMS), Moscow, Russian Federation. tmaximova@mail.ru.
authors.forename: Tamara
authors.initials: T
authors.lastname: Maximova
authors.affiliation: National Institute of Public Health (INSP), Centre for Evaluation Research and Surveys, Cuernavaca, Morelos, Mexico. bmanrique@insp.mx.
authors.forename: Betty Manrique
authors.initials: BM
authors.lastname: Espinoza
authors.affiliation: National Institute of Public Health (INSP), Centre for Evaluation Research and Surveys, Cuernavaca, Morelos, Mexico. asalinas@insp.mx.
authors.forename: Aarón Salinas
authors.initials: AS
authors.lastname: Rodríguez
authors.affiliation: Academic Unit of Primary Care and Population Sciences, Faculty of Medicine, University of Southampton, University Road, Southampton, SO17 1BJ, UK. sa2706@soton.ac.uk.
authors.forename: Sara
authors.initials: S
authors.lastname: Afshar
authors.affiliation: Indian Institute of Public Health, Bhubaneswar, Public Health Foundation of India, Bhubaneswar, Odisha, India. sanghamitra.pati@iiphb.org.
authors.forename: Sanghamitra
authors.initials: S
authors.lastname: Pati
authors.affiliation: Ohio University, Department of Social Medicine and Director of Global Health, Athens, OH, USA. iceg@ohio.edu.
authors.forename: Gillian
authors.initials: G
authors.lastname: Ice
authors.affiliation: Centre for Dementia Studies, Brighton and Sussex Medical School, University of Sussex, Brighton, UK. s.banerjee@bsms.ac.uk.
authors.forename: Sube
authors.initials: S
authors.lastname: Banerjee
authors.affiliation: University of Oregon, Department of Anthropology, Eugene, OR, USA. liebert@uoregon.edu.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Liebert
authors.affiliation: University of Oregon, Department of Anthropology, Eugene, OR, USA. jjosh@uoregon.edu.
authors.forename: James Josh
authors.initials: JJ
authors.lastname: Snodgrass
authors.affiliation: World Health Organization, Statistics Measurement and Analysis Unit, Geneva, Switzerland. naidoon@who.int.|World Health Organization Study on global AGEing and adult health (SAGE), Geneva, Switzerland. naidoon@who.int.
authors.forename: Nirmala
authors.initials: N
authors.lastname: Naidoo
authors.affiliation: World Health Organization, Statistics Measurement and Analysis Unit, Geneva, Switzerland. chatterjis@who.int.|World Health Organization Study on global AGEing and adult health (SAGE), Geneva, Switzerland. chatterjis@who.int.
authors.forename: Somnath
authors.initials: S
authors.lastname: Chatterji
authors.affiliation: World Health Organization Study on global AGEing and adult health (SAGE), Geneva, Switzerland. kowalp@who.int.|University of Newcastle Priority Research Centre for Gender, Health and Ageing, Newcastle, NSW, Australia. kowalp@who.int.
authors.forename: Paul
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mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000375:Aging; D002908:Chronic Disease; D015897:Comorbidity / Q000639:trends*; D003430:Cross-Sectional Studies; D003863:Depression / Q000453:epidemiology*; D003906:Developing Countries; D005260:Female; D006801:Humans; D008297:Male; D008603:Mental Health / Q000706:statistics & numerical data; D008875:Middle Aged; D011203:Poverty / Q000706:statistics & numerical data; D015995:Prevalence; D011788:Quality of Life