Living the Good Life? Mortality and Hospital Utilization Patterns in the Old Order Amish
et al. (2012) Living the Good Life? Mortality and Hospital Utilization Patterns in the Old Order
Amish. PLoS ONE 7(12): e51560. doi:10.1371/journal.pone.0051560
Living the Good Life? Mortality and Hospital Utilization Patterns in the Old Order Amish
Braxton D. Mitchell 0
Woei-Jyh Lee 0
Magdalena I. Tolea 0
Kelsey Shields 0
Zahra Ashktorab 0
Laurence S. Magder 0
Kathleen A. Ryan 0
Toni I. Pollin 0
Patrick F. McArdle 0
Alan R. Shuldiner 0
Alejandro A. Scha ffer 0
Manlio Vinciguerra, Foundation for Liver Research, United Kingdom
0 1 Department of Medicine, Program for Personalized and Genomic Medicine, University of Maryland School of Medicine , Baltimore , Maryland, United States of America, 2 National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Department of Health and Human Services , Bethesda , Maryland, United States of America, 3 Department of Epidemiology & Public Health, Program for Personalized and Genomic Medicine, University of Maryland School of Medicine , Baltimore , Maryland, United States of America, 4 Geriatric Research and Education Clinical Center, Veterans Administration Medical Center , Baltimore, Maryland , United States of America
Lifespan increases observed in the United States and elsewhere throughout the developed world, have been attributed in part to improvements in medical care access and technology and to healthier lifestyles. To differentiate the relative contributions of these two factors, we have compared lifespan in the Old Order Amish (OOA), a population with historically low use of medical care, with that of Caucasian participants from the Framingham Heart Study (FHS), focusing on individuals who have reached at least age 30 years. Analyses were based on 2,108 OOA individuals from the Lancaster County, PA community born between 1890 and 1921 and 5,079 FHS participants born approximately the same time. Vital status was ascertained on 96.9% of the OOA cohort through 2011 and through systematic follow-up of the FHS cohort. The lifespan part of the study included an enlargement of the Anabaptist Genealogy Database to 539,822 individuals, which will be of use in other studies of the Amish. Mortality comparisons revealed that OOA men experienced better longevity (p,0.001) and OOA women comparable longevity than their FHS counterparts. We further documented all OOA hospital discharges in Lancaster County, PA during 2002-2004 and compared OOA discharge rates to Caucasian national rates obtained from the National Hospital Discharge Survey for the same time period. Both OOA men and women experienced markedly lower rates of hospital discharges than their non-Amish counterparts, despite the increased lifespan. We speculate that lifestyle factors may predispose the OOA to greater longevity and perhaps to lesser hospital use. Identifying these factors, which might include behaviors such as lesser tobacco use, greater physical activity, and/or enhanced community assimilation, and assessing their transferability to non-Amish communities may produce significant gains to the public health.
Funding: This work was supported by research grants R01 HL69313, R01 DK54261, R01 AG1872801, R01 HL088119, R01 AR046838, and U01 HL72515 from the
National Institutes of Health. KS was supported by a summer internship made available through the Mid-Atlantic Nutrition and Obesity Research Center (P30
DK072488). This research was supported in part by the Intramural Research Program of the National Institutes of Health, National Library of Medicine. The authors
also gratefully acknowledge the support and helpful discussions with our Amish liaisons and field workers and with our Amish Research Clinic Community Board,
including Mr. Davie Stoltzfus, who is in charge of Amish Care. The funders had no role in study design, data collection and analysis, decision to publish, or
preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
Average lifespan in the United States (US), as in many other
developed countries throughout the world, has been increasing
over time . Within the US, more economically advantaged
persons live longer . This advantage that has been attributed to
multiple factors, including: better access to high quality medical
care and a lower rate of tobacco use. In particular, the death rate
from cardiovascular events has decreased dramatically over the
past 30 years . The decrease in cardiovascular deaths has been
attributed in part to improvements in rushing heart attack sufferers
to the hospital and administering life-saving emergency treatments
both in the ambulance and in the emergency room [4,5]. Changes
such as cholesterol-lowering drugs, decreases in smoking and heart
healthier diets, are also important contributors.
The relative contributions to lifespan made by improvements in
medical care access and technology versus improvements in
lifestyle have been hard to quantify. This is an important issue in
public policy given that lifespan in the US lags behind that of
many other developed nations despite health care costs in the US,
estimated at $2.6 trillion in 2010 , that dwarf those in other
To address this issue, we have estimated lifespan in the Old
Order Amish (OOA), a subpopulation within the US with low
utilization of specialized health care. The OOA do not participate
in government-sponsored plans, such as Medicare and Medicaid,
and are generally self-insuring as a group. Access may be further
limited because OOA do not own cars and may find it difficult to
reach locations where specialized health care is delivered.
Although they avoid most forms of modern technology, the
OOA do seek modern health care and hospitals, as we quantify in
Concurrent with their reduced access to health care and
especially high technology health care, the OOA lifestyle is
distinctive in other ways, some of which may be health-promoting.
Especially notable is the degree to which Amish core beliefs in
church, community, and selflessness permeate daily life.
Compared to non-Amish, Amish are very physically active; they
maintain a traditional lifestyle, still utilizing the horse and buggy as
their main mode of transportation and do not use electricity in
their homes. The Amish also differ from the non-Amish in several
other lifestyle factors, including smoking habits and cardiovascular
Gaining a more complete picture of the medical utilization
patterns and overall health of the OOA may be revealing. In this
report, we characterize mortality rates and hospital discharge rates
in the Amish and contrast them with those in non-Amish
This report is based on the OOA community living in Lancaster
County, PA, whom we have been studying since 1993. This
community was founded by hundreds of individuals who
immigrated to this area from central Europe during the early
18th century, with the present day Lancaster County OOA
community comprised of their descendants. Our analysis plan
consisted of two parts. First, we used a newly enlarged Anabaptist
Genealogy Database Version 5 (AGDB5) to identify a birth cohort
of 2,108 OOA born between 18901921 who lived until age 30
years or older and compared mortality in these individuals to that
in Caucasian participants of the Framingham Heart Study (FHS).
Second, we compared hospital discharge rates between OOA and
US Caucasians from the National Hospitalization Discharge
Survey (NHDS). To find suitable denominators, we used published
registry data to compile a census of all OOA residing in Lancaster
County in 2002. To find the corresponding numerators, we
identified all OOA discharges from Lancaster county area
hospitals from 20022004 to provide estimates of hospital
Mortality in OOA vs FHS
Amish mortality cohort. We identified a cohort of OOA
individuals born between 1890 and 1921 whose vital status we
ascertained. This Amish mortality cohort comprised ancestors and
their siblings of the 4,200 OOA individuals who had participated
in one or more of the population studies carried out in this
community from 19952010 by our group . By using
subjects we had studied, we assured that they were practicing
OOA living in Lancaster County. Identification of the relatives
was made possible by accessing the AGDB, a computer-searchable
genealogy database of the OOA and other Anabaptist populations
dating back to the OOA immigration to the US that was
generated and is managed by co-author AAS and colleagues at the
NIH. There are multiple versions of AGDB  constructed
using various sources and updates. The mortality part of the study
included the expansion of AGDB to include major updates of two
of the sources and to increase the size to 539,822 individuals (see
Information S1). Figure S1 shows the overlaps of the three sources
used to construct AGDB5.
The characterization of a cohort from AGDB5 to study
mortality is illustrated schematically in Figure S2. From AGDB5,
we identified a total of 9,778 ancestors and their siblings, of whom
2,259 survived until at least age 30 years and were born between
1890 and 1921. We excluded subjects with missing death dates
who had a recorded birth place outside of Lancaster County
(n = 151). Of the 2,108 remaining individuals, 121 were born in
Lancaster County but had no date of death. Further review and
fieldwork by our staff of research nurses and Amish liaisons
identified dates of death for 11 of these 121 subjects and confirmed
45 others to be alive as of January 1, 2011. The remaining 65
subjects (13 reported as deceased but with unknown year of death,
and 52 with unknown vital status) were excluded from our
analysis. Mortality follow-up was thus complete on 96.9% (2,043/
2,108) of the cohort (see Information S1 for additional detail).
FHS mortality cohort. The FHS is a longitudinal study of
factors influencing the development of cardiovascular disease .
The original FHS cohort comprised 5,079 subjects, born between
1887 and 1921, who were aged 2862 years at enrollment into the
study in 19481952. All were invited back every two years for a
repeat examination. We obtained the 2012 release of the
FHSCohort dataset with vital status follow-up through 2007 from the
NHLBI BioLINCC website (https://biolincc.nhlbi.nih.gov/).
Through 2007, 4,745 of the original FHS participants had died
(93.4%) and had available death dates. Participants with no death
date recorded (n = 334) were censored as of date of last contact.
Mortality comparison. The Amish entered the mortality
cohort on the day of their 30th birthday. FHS participants entered
on the day of their baseline FHS visit. We used proportional
hazards regression analysis to compare the survival functions
between the two cohorts. Analyses were carried out in men and
women separately using the PHREG procedure of the SAS
software package (Cary, NC).
We estimated the population size of the Lancaster County
Amish community using residence information obtained from the
2002 Church Directory of the Lancaster County Amish . In
2002, the Amish Lancaster community included 141 distinct OOA
church districts, of which 132 are situated in Lancaster County.
Each district comprises 1750 households (mean households/
district = 30) . The Church Directory enumerates for each
district all household members and their birthdates. We sampled
30 districts (23%), selected at random, enumerated the number of
OOA individuals by age and sex, and then extrapolated the
numbers of OOA in all 132 districts in Lancaster County. More
details are in the Information S1 and in Table S1.
Hospital discharge survey
We carried out a population-based ascertainment to identify all
hospital discharges (deceased or alive) among the OOA from
Lancaster County for the 3-year period January 1, 2002 to
December 31, 2004. We previously used this approach to estimate
rates of hip fractures in the Amish . Discharges were recorded
via a review of the medical records from the four area hospitals in
the Lancaster County area that encompass the likely encatchment
area for the OOA (see Figure S1).
We restricted our analysis of discharge records for OOA
individuals age$25 years, to focus on adults. Patients were
identified by the hospitals as Amish either because they had
specified their religious affiliation as Amish or had indicated
participation in the Amish Aid plan as their means of health
insurance. We verified OOA religious affiliation and residency in
Lancaster County by cross-referencing patient names with the
OOA Church Directory, which contains only OOA (vs other
Amish groups), and/or verification with an Amish research liaison.
Out of 658 OOA discharges identified by the four hospitals, 181
did not meet validation (i.e., lived outside of Lancaster County or
were not OOA), leaving 477 confirmed OOA discharges. For each
discharge, we recorded the principal diagnosis and up to 6
additional discharge diagnoses. Discharges were coded using
Hospital discharge rates in the OOA were determined by
dividing the number of discharges by the population at risk and
were compared with those in Caucasians from the NHDS for
years 20022004. The NHDS, conducted since 1965, represents
the main source of national data on characteristics of patients
discharged from US non-federal short-stay hospitals. The survey
collects data from a sample of medical records obtained from a
nationally representative sample of short-stay, general hospitals.
We compared rates between OOA and NHDS using the indirect
method for age-adjustment . Specifically, we used the NHDS
discharge rates to compute the expected number of discharges in
the OOA had this group experienced the same rates as those
observed from the NHDS.
The study was approved by the University of Maryland
Institutional Review Board. Informed consent was not obtained;
the mortality component of the study was based on publicly
available data maintained by NIH through the AGDB (Amish)
and NHLBI BioLINCC Biorespository (Framingham Heart
Study), and a waiver for informed consent was granted by the
Directors of Research from Lancaster Regional Medical Center,
Ephrata Community Hospital, and Ephrata Community Hospital
because the study involved a review of medical records only, did
not require collection of personal identifying information, and the
research could not be reasonably conducted without a waiver of
Of the 2,043 subjects in the OOA mortality cohort (birth years
18901921), 1,998 were known to be deceased (97.8%) by 2010
and the remaining 45 confirmed as alive through January 1, 2011.
Ages at death of the 1,998 deceased subjects ranged from 30103
years. By virtue of their participation in FHS (birth years 1887
1921), all subjects lived until at least age 30 years. Ages at death
among the 93.4% of the FHS cohort in whom death dates were
reported ranged from 32104 years.
Figures 1a and 1b show the survival curves for OOA and FHS
women and men, respectively. Amish men were expected to live
on average 3 years longer than their FHS counterparts (hazard
ratio 1.23, 95% confidence intervals 1.141.32; p,0.001), while
there was virtually no difference in expected life expectancy
between OOA and FHS women (hazard ratio 0.95, 95%
confidence intervals 0.881.02; p = 0.15).
Hospital discharge rates in the OOA and comparison with
From the 2002 Church Directory of the Lancaster County
Amish, we estimated there to be ,21,850 OOA individuals
residing in Lancaster County, PA, including ,7,502 aged 25 years
and older. (see Table S1 for estimated age and sex distribution of
OOA residents of Lancaster County.)
Annualized rates of first- and any-listed hospital discharges for
each diagnostic category are shown in Table 1 for the OOA and
for the US Caucasian population. OOA and US Caucasian men
shared four of the top five diagnostic categories for first-listed
hospital discharges (circulatory, injuries/poisoning, digestive, and
respiratory), and OOA and US Caucasian women shared three of
the top five diagnostic categories (circulatory, injuries/poisoning,
and digestive). In the five leading diagnostic categories observed in
OOA, first-listed discharge rates were substantially lower in OOA
than in US Caucasians, with the exception of complications of
labor, childbirth, and the puerperium, which were higher in OOA
compared to US Caucasian women (Figures 2a and 2b). See
Tables S2, S3, S4, S5 for age-specific comparisons of first- and
any-listed hospital discharge rates between OOA and US
When adjusting for age differences between the two
populations, OOA men and women experienced substantially lower rates
of first-listed (Figure 3) and any-listed (Information S1) of hospital
discharges for the major categories (p,0.05 for each comparison),
with the exceptions of a 3.2-fold greater excess (95% confidence
interval: 2.553.85) among OOA women of first-listed hospital
discharges for complications of labor and pregnancy, and a
2.5fold excess (95% confidence interval: 1.253.68) of first-listed
hospital discharge rates among OOA men for supplemental
conditions. Since OOA women have on average three times as
many children as US Caucasian women (,7 children per OOA
mother on average), then the hospital discharge rates normalized
for number of births are similar between OOA and US Caucasian
women. The ratios comparing hospital discharge rates are in
Our analyses reveal that OOA men experience better longevity
than Caucasian men from the FHS and OOA women experience
comparable longevity, despite a much lower rate of
hospitalizations. This is a remarkable observation in light of escalating costs
of medical care in the US. That OOA have reduced usage of
medical care has been noted anecdotally [21,22], but to our
knowledge, has not previously been quantified systematically. Our
extensive interactions with the OOA community over the past 18
years suggest that the reduced OOA usage of health care is
primarily due to cultural norms regarding when to seek medical
care due in part to community refusal to use health insurance, and
secondarily to limits on transportation.
That OOA adults have better or similar longevity compared to
non-Amish Caucasian adults was first reported over 30 years ago
by Hamman et al., who observed from their analysis of death
certificates that OOA men experience lower mortality rates than
non-Amish residents of the same counties. In that study, there
were no significant differences in mortality between OOA women
and non-Amish women at ages 4069 years, and higher mortality
rates among OOA women over age 69 years . The survival
advantage experienced by OOA men was due principally to lower
rates of cancer and cardiovascular diseases. Our study updates and
extends Hammans earlier study in two important ways, first by
focusing on a more contemporaneous period of study and second
by computing lifespan directly, allowing for direct comparison
with the FHS. Our cohort analysis is thus protected against
potential biases inherent in death certificate studies that can arise
from incomplete ascertainment of death certificates or under/
over-estimation of the population.
We quantified a dramatically lower hospitalization discharge
rate in OOA compared to the US Caucasians. The lower rate
among the OOA is evident across a wide spectrum of diagnostic
categories. While we likely undercounted discharges for mental
conditions by not including regional specialty behavioral clinics in
our survey, we acknowledge that it is also possible that we may
have undercounted the number of OOA discharges at the primary
hospitals since they were identified on the basis of self-reported
religious affiliation or use of the Amish Aid health plan. It is
further possible that some Amish may have received medical care
in hospitals outside of the Lancaster County area. A modest
undercount would not have materially affected our conclusions
since for most diagnostic categories the US Caucasian hospital
discharge rates were 310 times higher than those in the OOA.
While hospital discharge rates for complications of labor,
childbirth, and the puerperium were approximately 4 times higher
among OOA compared to US Caucasian women, they were more
or less comparable after considering the 34-fold higher number of
children observed among OOA women. Our study cannot address
whether the lower hospitalization discharge rates of the OOA
indicate that the OOA have less need of hospital care than
nonAmish because they are healthier, or whether greater access to
hospitals would improve lifespan further. Indeed, these two
possibilities are not mutually exclusive.
We speculate that lifestyle factors may predispose the OOA to
better health, lesser need for hospitalizations, and greater
longevity. But which components? We have previously compared
traditional cardiovascular risk factors between OOA and
nonAmish Caucasians and shown that while OOA have less
abdominal obesity (as measured by waist circumference) despite
comparable body mass index compared to non-Amish (28.4 vs
28.5 kg/m2), they also have a less advantageous lipid profile as
indicated by significantly higher total (5.5 vs 5.2 mmol/L) and
LDL (3.59 vs 3.04 mmol/L) cholesterol levels . Diastolic blood
pressure levels are also significantly higher in OOA individuals
(72.0 vs 70.4 mmHg), and the OOA are much less likely to take
lipid-lowering (3.7% vs 22.9%) or blood pressure-lowering (6.2%
vs 22.5%) medications compared to their non-Amish counterparts.
Despite the overall less beneficial cardiovascular risk factor
profile of OOA in terms of lipids and blood pressure, OOA have
more favorable patterns of several other important cardiovascular
risk factors. First, OOA are on average considerably more
physically active than non-Amish. In a recent study, we measured
physical activity levels by accelerometry in OOA and non-Amish
children and found OOA children to be 3.3 times less likely to be
overweight than non-Amish children and physical activity levels to
be substantially higher in the OOA children, with boys more
active than girls in both groups, but OOA girls easily more active
than non-Amish boys . Moreover, despite comparable levels of
BMI, we have also previously reported the prevalence of type 2
diabetes is ,50% lower in the OOA compared to US Caucasians
, a result we have speculated may be due to higher physical
activity levels . We have similarly documented high levels of
physical activity in Amish adults .
Second, rates of cigarette smoking are significantly lower in the
OOA than non-Amish [10,28], with ,20% of OOA men
reporting that they smoke and virtually no women. Moreover,
among OOA reporting that they smoke, the intensity of smoking
tends to be low (i.e., most smokers report weekly cigar smoking).
According to the Centers for Disease Control, adults who smoke
cigarettes on average, die 14 years earlier than nonsmokers .
Approximately 52% of Framingham Heart Study subjects
reported themselves as smokers during their baseline visit 
and assuming a 10% overall smoking rate in OOA, then we
crudely estimate that the reduced level of smoking in the OOA
could account for as much as a 5.9 yr longer lifespan as compared
to FHS participants (calculated as (0.520.10) 614 years).
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Third, the role of sociocultural factors in health and disease is
complex, but the very cohesive nature of the OOA community,
including its strong social support network may provide significant
benefits to health and recovery. Almost all elderly Amish are cared
for by their families with assisted care or nursing home placements
very uncommon. The health and lifespan enhancing benefits of
social relationships are speculated to operate indirectly by
moderating or buffering the deleterious influence of stressors on
health and/or promoting the development of individual cognitive,
emotional, and behavioral skills . In a recent meta-analysis of
over 300,000 subjects, components of social relationships were
associated with decreased mortality, and notably the magnitude of
the effect was on par with that of quitting smoking and exceeded
those associated with other large risk factors such as obesity and
physical inactivity .
In addition to environmental and lifestyle factors, it is also
possible that differences in genetic background between OOA and
FHS participants contribute to differences in their mortality
experience. The genetic background of the OOA is unique in the
sense that the Lancaster settlement represents a founder
population such that virtually all 30,000 OOA current residents are
descendants of a few hundred founders who immigrated to the
region in the early 1700s . As a consequence of this history,
the OOA gene pool is relatively defined, resulting in a relative
excess in the frequency of consanguineous marriages. Renowned
geneticists have tried to estimate the deleterious effects of
inbreeding for over 50 years and there is evidence of increased
mortality in children and young adults, but these studies of
inbreeding have been unable to estimate any effects on
postreproductive mortality and longevity [34,35]. However, there is at
least some evidence that inbreeding is associated with increased
cardiovascular risk in adulthood, including higher levels of blood
pressure and cholesterol levels .
In the past 30 years in the US, the cost of health care has
increased dramatically and much faster than the rate of inflation
. Despite these costs, OOA adults, who use hospitals at a far
lower rate than non-Amish, experience comparable or better
lifespan than their non-Amish counterparts. From this perspective,
our data highlight the need to more fully understand the factors
that contribute to fewer hospitalizations in OOA adults. The
benefits of such factors at the population level could be larger than
the incremental gains associated with improvements in medical
care access. Our results suggest that interventions targeted at
lifestyle factors may have higher impact on improving lifespan at
the population level than improvements in medical technology and
medical care access. Identifying these factors, and assessing their
transferability to non-Amish communities may produce significant
gains to the public health. The expansion of AGDB to version 5 is
already proving useful in other studies of the Amish where
relationship information is needed (e.g., ).
Figure S1 Lancaster County, including locations of
Lancaster General Community Hospital (1), Lancaster
Regional Medical Center (2), Ephrata Community
Hospital (3), and Ephrata Community Hospital (4). From
Construction of the OOA mortality cohort.
Table S1 Age and sex distribution of the Lancaster
County Old Order Amish population as of July 1st 2002 *
(percentages in parentheses).
Table S2 Three-year rates of first-listed hospital
discharges (per 10,000) among Old Order Amish residing in
Lancaster County, Pennsylvania, 20022004.
Table S3 Three-year rates of first-listed hospital
discharges (per 10,000), Caucasians from the NHDS, 2002
Table S4 Three-year rates of any-listed hospital
discharges (per 10,000) among Old Order Amish residing in
Lancaster County, Pennsylvania, 20022004.
Table S5 Three-year rates of any-listed hospital
discharges (per 10,000), Caucasians from the NHDS, 2002
Table S6 Standardized ratios* comparing hospital
discharge rates for any-listed diagnostic procedures
between Old Order Amish and non-Amish whites, 2002
2004. Non-Amish white rates from the NHDS.
We gratefully acknowledge the support and helpful discussions with our
Amish liaisons and field workers and with our Amish Research Clinic
Community Board, including Mr. Davie Stoltzfus, who is in charge of
Conceived and designed the experiments: BDM MIT AAS LSM ARS.
Performed the experiments: BDM W-JL MIT KS ZA KAR TIP AAS.
Analyzed the data: BDM W-JL MIT KS ZA LSM KAR TIP PFM AAS.
Contributed reagents/materials/analysis tools: W-JL ZA AAS. Wrote the
paper: BDM W-JL MIT KS PFM AAS.
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