Disability Transitions and Health Expectancies among Adults 45 Years and Older in Malawi: A Cohort-Based Model

Disability Transitions and Health Expectancies among Adults 45 Years and Older in Malawi: A Cohort-Based

Model

Collin F Payne, UPenn GGD & PSCJames Mkandawire, IKI MalawiHans-Peter Kohler, UPenn PSC

GHME 2013June 18

Population growth by age group in SSA 2010–2060 (2010 = 100), share of total

population by age groups

Source: authors’ calculations based on United Nations World Population Prospects 2010 population projections.

SSA: Person Years Lived Above Age 25 By Age Group

Source: authors’ calculations based on United Nations World Population Prospects 2010 population projections.

• Evidence about health and disability among older adults in SSA is very limited

• High levels of labor force participation: 98% for age 50–64, 90% for age 65+ based on the 2009 Malawi Welfare Monitoring Survey (WMS)

• Individuals are very poorly served by the existing health infrastructure in SSA—government health clinics are not equipped to deal with the chronic diseases of aging

Focus on Mature Adults (= individuals aged 45+)

Our Research

• Focus on day-to-day activities in domains relevant to the subsistence-agriculture context of rural Malawi. – Analyze patterns of transition between levels of

disability across age– Estimate health expectancies (HEs) in levels of

disability

• Characterize processes of health, aging, and functional limitations in rural Malawi

• Seek to provide insights into the potential gains in well-being and economic productivity which could arise from investments in the health of older adults in SSA.

Malawi Longitudinal Survey of Families and Health (MLSFH)

• Longitudinal household panel conducted by UPenn

• Our analyses use data from 2006, 2008, and 2010 rounds• Parent sample added in 2008, bringing number of individuals

age 45+ to ~1,200

• HIV testing among individuals aged 45+ y in the 2008 MLSFH found an overall HIV prevalence of 3.3%.

• Basic demographic and socioeconomic characteristics are similar between our 2010 study population and the 45+ y rural population in the nationally representative Malawi 2010–2011 Third Integrated Household Survey (IHS3).

• Classification of physical limitations (“disability”) based on 2 questions from SF12 module – limitations in cooking and cleaning, walking to meetings

in the village, or tending to cattle and livestock

– limitations in carrying heavy loads, working on the farm, pounding maize, or digging a pit latrine

• Response categories of “limited a lot”, “limited a little”, or “not limited”

• Disability Status (“lived experience with disability”)– healthy: no limitations in either set of activities

– moderately limited: “limited a little” in either set of activities

– severely limited: “limited a lot” in either set of activities

Disability Status

Self-Reported disability, % working for income, pain interfering with work, and subjective well-

being

Source: Payne CF, Mkandawire J, Kohler H-P (2013) Disability Transitions and Health Expectancies among Adults 45 Years and Older in Malawi: A Cohort-Based Model. PLoS Med 10(5): e1001435. doi:10.1371/journal.pmed.1001435

Analysis Model• Microsimulation-based multistate life table—based on the

Stochastic Population Analysis for Complex Events (SPACE) program.

1) Estimate transition probabilities• Estimate conditional (on age, sex, and health state) annual probabilities of transitioning between health states (healthy, moderately limited, severely limited, dead): 2) Generate health expectancies• Create synthetic cohorts of 100,000 45-, 55-, 65-, and 75-y-old

individuals with the same initial gender and health state distribution as our study population

• Microsimulation: ‘‘Age’’ these individuals forward year by year using conditional transition probabilities and rates of mortality estimated from the data, repeat until death.– Estimate CIs by analyzing 499 bootstrap re-samples of the initial dataset and

taking the central 95% of the resulting distribution

Estimated Annual Transition Probabilities between Health Statuses


A) From Healthy B) From Moderately Limited

Estimated Annual Transition Probabilities between Health Statuses


C) From Severely Limited D) Mortality Probabilities

Health expectancies: Average remaining life expectancy (LE) at ages 45–75


Discussion

• Functional limitations are associated with a lower likelihood of working for income and reduced work efforts in agriculture

• Risks of experiencing an onset of functional limitations are high compared to developed contexts

• Onset of functional limitations happens earlier in life– Proportion of remaining life spent in severe

limitation at age 45 is comparable to 80-year olds in the US

Implications• Older population in SSA has been largely

left out of health-focused interventions and policies, particularly those focusing on MDGs.

• Many policy makers in SSA hesitant to direct money to the elderly population, and see investment in the aging population as “irrelevant to core national development interests”.

• Based on our findings, we believe that sentiment is misguided—the high burden of disability among mature adults is associated with substantial loss of labor output.

Thanks!

• Any post-discussion questions:– [email protected]– Paper is available at PLOS Medicine• doi:10.1371/journal.pmed.1001435

• Acknowledgements:– I am supported by the NSF Graduate

Research Fellowship (Grant No. DGE-0822)

Disability Transitions and Health Expectancies among Adults 45 Years and Older in Malawi: A Cohort-Based Model

Technology

health of older adults

disability transitions

limited disability status

levels of disability

processes of health

health statuses source

disability healthy

aging population