The Mexican Health And Aging Study (MHAS): 20 Years of a longitudinal study
Written by: Rebeca Wong and Alejandra Michaels-Obregon
Published on: Feb 02, 2023
The Mexican Health and Aging Study (MHAS/ENASEM) is a national longitudinal household survey for the study of health, economic status, and quality of life among persons aged 50 and over in Mexico. The first survey of the MHAS was conducted in 2001 with national and urban-rural representation. The study has collected 6 waves of data over a period of 20 years, including follow-ups in 2003, 2012, 2015, 2018, and 2021. In addition to following the original sample, refreshment samples were added in 2012 and 2018. Starting in Wave 2, the MHAS protocol also included a next-of-kin interview regarding deceased participants (see MHAS Timeline below). The study was designed to prospectively evaluate the impact of disease on the health, function and mortality of adults living in private dwellings in both urban and rural areas in Mexico. The study protocols and survey instruments are highly comparable to the U.S. Health and Retirement Study (HRS).
The MHAS has an accumulated count of over 7,000 deaths among participants since the beginning of the study and a next-of-kin interview is completed on each. In addition, the survey instruments have been evolving to include new content on psychosocial aspects such as personality, life satisfaction, consciousness and locus of control, time use, sleep, last year of life, as well as questions to study the impact of COVID-19. In addition, the MHAS has also completed ancillary studies in sub-samples to capture anthropometric (weight, height, and waist and hip circumference) and performance measures (hand grip, timed walk, balance) in 2001 and 2003; anthropometric and performance measures, and a selection of biomarkers in 2012; and an in-depth cognitive assessment in a subsample, the Cognitive Aging Ancillary Study (Mex-Cog), using a harmonized cognitive assessment protocol (HCAP) in 2016 and 2021.
Finally, the study continuously updates and includes new linkages to expand the analytical value of the surveys. For more details on the study background and design, see Wong et al. 2017 and MHAS 2018. To access the data files and documentation free of charge, visit the MHAS website. The MHAS website was recently updated to include an easy-to-use navigation system, improved content organization and layout, enhanced site performance and speed, larger fonts for easy reading, and a secure sockets layer (SSL). MHAS data have been used by researchers around the world both alone and in combination with other Health and Retirement Studies. As of December 2022, we report that about 19 percent of the peer-reviewed publications using MHAS data involve cross-national comparisons. Among the publications doing cross-national analyses, we can highlight Calvo et al. (2020) who estimate cross-national variation in the quantity and patterns of drinking throughout older ages, and investigate country-level variables explaining cross-national variation in alcohol consumption for individuals aged 50 and older. Newmyer et al. (2021) assess loneliness reported in large-scale aging studies in 31 countries. Matus-Lopez (2021) studies the population with long-term care needs in Latin America and compares the percentage of people needing care by age, health and living conditions. Lu et al. (2022) investigate longitudinal associations of physical disability and wealth with paid employment after age 60 in the US, England, Japan, Mexico and China. Verdery (2022) provides national profiles of COVID-19 high- and low-mortality risks by age and health conditions.
While The MHAS data are contained in several files, the Harmonized MHAS data file incorporates data from the core interview data, the master follow-up file, household roster data, and next-of-kin data. Working with the Gateway to Global Aging Data team, the MHAS also recently released a Harmonized MHAS End of Life file focusing on the MHAS next-of-kin interview. In addition, we will be releasing a Harmonized Mex-Cog file focusing on the MHAS Harmonized Cognitive Assessment Protocol. All harmonized data files and documentation are also available free of charge at the study website. The documentation for the Harmonized MHAS is also available here. The MHAS Is a collaborative effort among researchers from the University of Texas Medical Branch (UTMB), the Instituto Nacional de Estadística y Geografía (INEGI, Mexico), the Instituto Nacional de Geriatría (INGER, Mexico), Columbia University (New York), University of California Los Angeles (UCLA), and University of Southern California (USC). The MHAS is partly sponsored by the National Institutes of Health/National Institute on Aging (grant number NIH R01AG018016) in the United States and the Instituto Nacional de Estadística y Geografía (INEGI) in Mexico. The construction of the Harmonized MHAS data is funded by the National Institute on Aging (R01 AG030153).
- Wong R, Michaels-Obregon A, Palloni A. Cohort Profile - The Mexican Health and Aging Study (MHAS). Int J Epidemiol. 2017 Apr 1, 46(2), e2.
- Mejia-Arango S, Nevarez R, Michaels-Obregon A, Trejo-Valdivia B, Mendoza-Alvarado LR, Sosa-Ortiz AL, Martinez-Ruiz A, Wong R. The Mexican Cognitive Ancillary Study (Mex-Cog) - Study Design and Methods. Arch Gerontol Geriatr. 2020 Jul 27, 91, 104210.
- MHAS 2018. Mexican Health and Aging Study 2018, Methodological Document. PDF document.
- Calvo E, Allel K, Staudinger UM, Castillo-Carniglia A, Medina JT, Keyes KM. Cross-country differences in age trends in alcohol consumption among older adults - a cross-sectional study of individuals aged 50 years and older in 22 countries. Addiction. 2021 Jun, 116(6), 1399-1412.
- Lu W, Stefler D, Sanchez-Niubo A, Haro J, Marmot M, Bobak M. The associations of physical incapacity and wealth with remaining paid employment after age 60 in five middle-income and high-income countries. Aging and Society. 2022, 1-24.
- Matus-Lopez M, Chaverri-Carvajal A. Population with Long-Term Care Needs in Six Latin American Countries - Estimation of Older Adults Who Need Help Performing ADLs. Int J Environ Res Public Health. 2021 Jul 27, 18(15), 7935.
- Newmyer L, Verdery AM, Margolis R, Pessin L. Measuring Older Adult Loneliness Across Countries. J Gerontol B Psychol Sci Soc Sci. 2021 Aug 13, 76(7), 1408-1414.
- Verdery AM, Newmyer L, Wagner B, Margolis R. National Profiles of Coronavirus Disease 2019 Mortality Risks by Age Structure and Preexisting Health Conditions. Gerontologist. 2021 Jan 21, 61(1), 71-77.
- Rebeca Wong is a Mexican scholar who received a Ph.D. in Economics from the University of Michigan in 1987. Currently a professor at the University of Texas Medical Branch. She has pioneered the use of cross-national approaches to study health outcomes among international migrants. She serves as Principal Investigator of the Mexican Health and Aging Study (MHAS).
- Alejandra Michaels-Obregon (M.Sc) is a Research Project Manager at the University of Texas Medical Branch.