National Health Statistics Reports

Number 123  April 19, 2019

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

Diabetes and Prediabetes Among Adults in 

Los Angeles County and the United States,

1999–2006 and 2007–2014 

by Craig M. Hales, M.D., M.P.H., and Margaret D. Carroll, M.S.P.H., National Center for Health Statistics; and 

Tony Kuo, M.D., M.S.H.S., and Paul A. Simon, M.D., M.P.H., Los Angeles County Department of Public Health

Abstract

Objective—This report presents the prevalence of diagnosed diabetes, 

undiagnosed diabetes, total diabetes, and prediabetes among adults aged 20 and over 

in Los Angeles County and the United States in 1999–2006 and 2007–2014. The 

prevalence of diagnosed diabetes, total diabetes, and prediabetes in 2007–2014 are 

presented by age, sex, and race and Hispanic origin.

Methods—Data are from in-home interviews and laboratory testing conducted 

as part of the National Health and Nutrition Examination Survey (NHANES). Los 

Angeles County has been selected with certainty in every NHANES cycle since 

1999. Sample persons in Los Angeles County were selected and sample weights 

constructed so that estimates represent the county. Prevalence and 95% confidence 

intervals for diagnosed, undiagnosed, total diabetes, and prediabetes were estimated 

using self-reported diagnosis of diabetes, plasma fasting glucose, and hemoglobin 

A1c. Differences in prevalence were tested between Los Angeles County and 

the United States, between 1999–2006 and 2007–2014, and among demographic 

subgroups.

Results—The age-adjusted prevalence of total diabetes among adults in Los 

Angeles County increased from 10.5% in 1999–2006 to 14.4% in 2007–2014. In 

2007–2014, 40.2% of adults in Los Angeles County had prediabetes. There were no 

significant differences in the overall prevalence of diagnosed diabetes, undiagnosed 

diabetes, total diabetes, or prediabetes between Los Angeles County and the 

United States in 1999–2006 or 2007–2014. The prevalence of diagnosed diabetes, 

total diabetes, and prediabetes increased with age in both Los Angeles County and 

the United States. The prevalence of total diabetes was higher in non-Hispanic black 

adults, Hispanic adults, and Mexican-American adults than in non-Hispanic white 

adults in both Los Angeles County and the United States.

Conclusion—Monitoring trends in diagnosed diabetes, undiagnosed diabetes, total 

diabetes, and prediabetes among adults in Los Angeles County and the United States 

may inform the development and implementation of targeted prevention and control 

efforts.

Keywords: National Health and Nutrition Examination Survey (NHANES) • plasma 

fasting glucose • hemoglobin A1c

Introduction

Diabetes is a major cause of 

morbidity and mortality in the 

United States (1–3). Data from the 

California Health Interview Survey 

shows that 55% of the adult population 

in California, or 15.5 million people, 

were estimated to have prediabetes or 

diabetes in 2013–2014 (4). Los Angeles 

County has the largest population of 

any county in the United States, and has 

been included in the National Health 

and Nutrition Examination Survey 

(NHANES) since 1999. NHANES 

data from Los Angeles County for the 

most recent 8-year period, 2007–2014, 

have been used to estimate the 

prevalence of hypertension (5) and 

several infectious diseases (6), and to 

compare with prevalence estimates for 

the United States. This report presents 

estimates of the prevalence of diagnosed 

diabetes, undiagnosed diabetes, total 

diabetes, and prediabetes for adults aged 

20 and over in Los Angeles County for 

1999–2006 and 2007–2014, and provides 

prevalence estimates by age, sex, and 

race and Hispanic origin for 2007–2014 

for Los Angeles County and the U.S. 

adult population.

NCHS reports can be downloaded from: https://www.cdc.gov/nchs/products/index.htm.
Page 2 National Health Statistics Reports  Number 123  April 19, 2019

Methods

Data source

NHANES is a cross-sectional 

survey designed to monitor the health 

and nutritional status of the civilian 

noninstitutionalized U.S. population. 

NHANES is conducted by the National 

Center for Health Statistics (NCHS) 

and consists of interviews conducted in 

the participant’s home, a standardized 

physical examination in a mobile 

examination center, and laboratory tests 

on blood and other specimens.

The NHANES sample is based on a 

complex, multistage probability design 

that includes oversampling of particular 

population subgroups to obtain reliable 

estimates of health and nutritional 

measures for these groups. In 1999–2006, 

Mexican-American persons, and in 

2007–2014 all Hispanic persons, were 

among the subgroups oversampled. Race 

and Hispanic origin-specific estimates 

reflect persons reporting only one race; 

those reporting more than one race are 

included in the total, but are not reported 

separately.

The NHANES sampling plan 

consists of four stages: selection 

of primary sampling units (PSUs), 

counties, or groups of contiguous 

counties; selection of segments within 

PSUs; selection of dwelling units 

within segments; and selection of 

sample persons within dwelling units 

(7). Because of the size and population 

density of Los Angeles County and the 

large Mexican-American and Hispanic 

population, a primary sampling unit in 

Los Angeles County was chosen with 

certainty in each 2-year NHANES 

cycle (8,9). Data were aggregated over 

1999–2006 and 2007–2014 in order to 

increase the sample size and improve the 

reliability of estimates for Los Angeles 

County. Sample weights were calculated 

for Los Angeles County and U.S. 

survey participants for the two, 8-year 

periods 1999–2006 and 2007–2014; 

sample weighting methods are described 

elsewhere (9).

Measurement of diabetes 

and prediabetes

Participants were randomly assigned 

to a morning or an afternoon or evening 

examination session. Those assigned 

to the morning session were asked to 

fast for at least 8 hours but fewer than 

24 hours prior to examination, and 

the estimates of diabetes prevalence 

presented in this report are based on 

adults aged 20 and over examined in 

the morning who fasted for at least 8 

hours but fewer than 24 hours prior to 

examination. Pregnant women were 

excluded. Forward calibration equations 

were used to account for changes in 

plasma glucose laboratory procedures 

over time (10,11). Participants were 

classified as having diagnosed diabetes 

if they answered “yes” to the question, 

“Other than during pregnancy, have 

you ever been told by a doctor or health 

professional that you have diabetes or 

sugar diabetes?” 

Current American Diabetes 

Association definitions were used 

to classify diabetes and prediabetes 

(12). Adults were classified as having 

undiagnosed diabetes if they did not have 

diagnosed diabetes and had a plasma 

fasting glucose equal to or greater than 

126 mg/mL or a hemoglobin A1c equal 

to or greater than 6.5%. Total diabetes 

was defined as having either diagnosed 

or undiagnosed diabetes. Participants 

were classified as having prediabetes if 

they did not have diabetes (diagnosed or 

undiagnosed), and their plasma fasting 

glucose was between 100 mg/dL and 

125 mg/dL or their hemoglobin A1c was 

between 5.7% and 6.4%. 

Statistical analyses 

Estimates of the prevalence of 

diabetes (diagnosed, undiagnosed, 

and total diabetes) and prediabetes in 

2007–2014 are presented by age group 

(20–39, 40–59, and 60 and over), 

sex, and race and Hispanic origin 

(non-Hispanic white, non-Hispanic black, 

Hispanic, and Mexican American); the 

Hispanic category includes Mexican 

Americans. Estimates for all adults, 

and estimates by sex and race and 

Hispanic origin are age adjusted by the 

direct method to the projected 2000 

U.S. Census population using the age 

groups 20–39, 40–59, and 60 and over 

(13). Reported prevalence estimates 

are age adjusted unless otherwise 

indicated. Differences in prevalence 

for all adults in 1999–2006 compared 

with 2007–2014, and differences in 

prevalence by sex and race and Hispanic 

origin in 2007–2014 were tested using a 

univariate 2-sided t-statistic, and linear 

trends across age categories were tested 

using logistic regression. Differences in 

overall prevalence estimates between the 

United States and Los Angeles County 

were tested with a univariate 2-sided 

t-statistic using the combined standard 

error accounting for the correlation 

between Los Angeles County and 

the United States (14). All reported 

differences are statistically significant 

(p < 0.05). No adjustments were made 

for multiple comparisons. Confidence 

intervals were constructed using the 

method of Korn and Graubard (15) and 

reliability of estimates was assessed using 

the NCHS data presentation standards for 

proportions, and include an evaluation 

of the effective sample size, degrees of 

freedom, confidence interval width, and 

relative confidence interval width (i.e., 

the confidence interval width divided by 

the estimate) (16). 

Despite the aggregation of 8 years 

of data, statistical analyses using the Los 

Angeles County sample may still lack 

adequate power to detect differences 

among subgroups at a magnitude that 

may be meaningful for public health. 

Statistical power was further decreased 

because only one-half of the adult 

NHANES sample was selected for the 

fasting subsample (for testing plasma 

fasting glucose). Reduced power 

limited the ability to calculate reliable 

estimates for health conditions with a low 

prevalence, especially among subgroups. 

Consequently, reliable estimates for the 

prevalence of undiagnosed diabetes in 

Los Angeles County were calculated for 

the overall population, but could not be 

calculated for sex, age group, or race and 

Hispanic-origin groups. 

Los Angeles County has a large 

proportion of Mexican-American and 

other Hispanic persons, and these groups 

were also oversampled in NHANES, 

resulting in a relatively large proportion 

of Mexican American persons in the Los 
National Health Statistics Reports  Number 123  April 19, 2019 Page 3

Angeles County sample. As a result, 

estimates for non-Hispanic white and 

non-Hispanic black persons may not 

be reliable and may have wide 95% 

confidence intervals when calculated 

using a subset of the sample (9), such 

as the fasting subsample. Statistical 

power to detect differences among 

race and Hispanic-origin groups in 

Los Angeles County was reduced 

substantially. Because of the issue with 

low statistical power in subgroups, 

differences between Los Angeles County 

and the United States for age, sex, and 

race and Hispanic origin were not tested 

statistically. 

All estimates in this report were 

calculated using the fasting sample and 

are weighted to represent the civilian 

noninstitutionalized population of Los 

Angeles County and the United States. 

Fasting sample weights account 

for unequal selection probabilities, 

probability of selection into the morning 

fasting sample, noncoverage, and 

nonresponse. Standard errors were 

estimated by Taylor Series linearization, 

which accounts for stratification and 

clustering in addition to weighting. 

Statistical analyses were performed 

using R version 3.5.1 (R Foundation for 

Statistical Computing) (17), the SAS 

System for Windows, version 9.3 (SAS 

Institute, Inc., Cary, N.C.) and SUDAAN 

version 11.0 (RTI International, Research 

Triangle Park, N.C.). 

Results 

Prevalence of diagnosed 

diabetes, undiagnosed 

diabetes, total diabetes, and 

prediabetes among adults 

aged 20 and over in Los 

Angeles County and in the 

United States from 1999–2006 

to 2007–2014

● In Los Angeles County, the 

age-adjusted prevalence of diagnosed 

diabetes was 7.5% in 1999–2006 

and 10.2% in 2007–2014, and in 

the United States, the age-adjusted 

prevalence of diagnosed diabetes 

increased from 7.2% in 1999–2006 

to 8.6% in 2007–2014 (Table 1). 

The pattern of diagnosed diabetes 

prevalence in Los Angeles County 

from 1999–2006 to 2007–2014 was 

similar to that of the United States, 

but no statistically significant 

difference in prevalence was detected 

for Los Angeles County.

● No significant difference in the

age-adjusted prevalence of 

undiagnosed diabetes in Los Angeles 

County was detected between 

1999–2006 (3.0%) and 2007–2014 

(4.3%). In the United States, the

age-adjusted prevalence of 

undiagnosed diabetes was similar in 

1999–2006 (3.5%) and 2007–2014 

(3.8%). 

● Among adults with diabetes in Los 

Angeles County in 2007–2014, 

29.9% had undiagnosed diabetes and 

among U.S. adults with diabetes, 

30.6% had undiagnosed diabetes 

(data not shown).

● In Los Angeles County, the 

age-adjusted prevalence of total 

diabetes increased from 10.5% in 

1999–2006 to 14.4% in 2007–2014. 

In the United States, the age-adjusted 

prevalence of total diabetes increased 

from 10.7% in 1999–2006 to 12.4% 

in 2007–2014.

● In Los Angeles County, the 

age-adjusted prevalence of prediabetes 

was 37.3% in 1999–2006 and 40.2% in 

2007–2014, and in the United States 

the age-adjusted prevalence of 

prediabetes increased from 37.2% in 

1999–2006 to 42.4% in 2007–2014. 

No statistically significant difference 

in prevalence between 1999–2006 

and 2007–2014 was detected for Los 

Angeles County.

● No statistically significant 

differences in the prevalence of 

diagnosed diabetes, undiagnosed 

diabetes, total diabetes, or 

prediabetes were detected between 

Los Angeles County and the 

United States in 1999–2006 or 

2007–2014.

● In 2007–2014 in Los Angeles 

County, the crude prevalence 

of diagnosed diabetes (9.9%), 

undiagnosed diabetes (4.1%), total 

diabetes (14.0%), and prediabetes 

(39.7%) was similar to age-adjusted 

estimates. The pattern of crude 

prevalence in Los Angeles County 

and the United States in 1999–2006 

and 2007–2014 was similar to that of 

the age-adjusted prevalence.

Prevalence of diagnosed 

diabetes among adults in 

Los Angeles County and the 

United States by age, sex, 

and race and Hispanic origin, 

2007–2014

● In Los Angeles County, the 

prevalence of diagnosed diabetes 

increased with age from 0.3% among 

adults aged 20–39 to 14.9% among 

those aged 40–59 and 19.4% among 

adults aged 60 and over (Table 2). In 

the United States, the prevalence of 

diagnosed diabetes increased with 

age, from 1.5% in adults aged 20–39 

to 9.4% in adults aged 40–59 and 

19.3% in adults aged 60 and over. 

● A higher prevalence of diagnosed 

diabetes was observed among men 

compared with women in Los 

Angeles County (13.1% compared 

with 7.5%), although a statistically 

significant difference was not 

detected. In the United States, the 

prevalence of diagnosed diabetes 

among men and women was similar 

(9.1% compared with 8.1%).

● In Los Angeles County, the 

prevalence of diagnosed diabetes 

was 5.5% among non-Hispanic white 

adults, 7.7% among non-Hispanic 

black adults, and 10.3% among 

Hispanic adults; however, 

significant differences among these 

estimates were not detected. In 

the United States, the prevalence 

of diagnosed diabetes was higher 

among non-Hispanic black adults 

(13.3%) and Hispanic adults (12.4%) 

compared with non-Hispanic white 

adults (7.1%). Prevalence was also 

higher among Mexican-American 

adults (13.4%) compared with 

non-Hispanic white adults in the 

United States.
Page 4 National Health Statistics Reports  Number 123  April 19, 2019

Prevalence of total diabetes 

among adults in Los Angeles 

County and the United States 

by age, sex, and race and 

Hispanic origin, 2007–2014

● In Los Angeles County, the 

prevalence of total diabetes increased 

with age from 1.1% among adults 

aged 20–39 to 19.8% among adults 

aged 40–59, and 28.6% among 

adults aged 60 and over. In the 

United States, the prevalence of total 

diabetes increased with age, from 

3.1% among adults aged 20–39 to 

13.5% among adults aged 40–59, 

and 26.6% among adults aged 60 and 

over (Table 2).

● Men had a higher prevalence of 

total diabetes than women in Los 

Angeles County (19.0% compared 

with 10.4%) and in the United States 

(14.0% compared with 11.0%).

● In Los Angeles County, the 

prevalence of total diabetes was 

higher among non-Hispanic black 

adults (17.9%) and Hispanic adults 

(14.9%) than among non-Hispanic 

white adults (6.4%). In the 

United States, the prevalence of 

total diabetes was also higher 

among non-Hispanic black adults 

(18.7%) and Hispanic adults (18.2%) 

compared with non-Hispanic white 

adults (10.3%). Prevalence was also 

higher among Mexican-American 

adults compared with non-Hispanic 

white adults in Los Angeles County 

(16.5% compared with 6.4%) and the 

United States (19.7% compared with 

10.3%).

Prevalence of prediabetes 

among adults in Los Angeles 

County and the United States 

by age, sex, and race and 

Hispanic origin, 2007–2014

● In Los Angeles County, the 

prevalence of prediabetes increased 

with age from 23.5% among adults 

aged 20–39 to 46.7% among adults 

aged 40–59, and 58.5% among 

adults aged 60 and over. In the 

United States, the prevalence of 

prediabetes increased with age, from 

33.2% among adults aged 20–39 

to 46.5% among adults 40–59, and 

51.7% among adults aged 60 and 

over (Table 2).

● In Los Angeles County, a higher 

prevalence of prediabetes was 

observed among men (42.0%) 

compared with women (38.0%), 

although no statistically significant 

difference was detected. In the 

United States, the prevalence of 

prediabetes was higher among men 

(48.2%) than women (36.5%).

● In Los Angeles County, the 

prevalence of prediabetes was 33.3% 

among non-Hispanic white adults, 

40.6% among non-Hispanic black 

adults, and 41.2% among Hispanic 

adults; however, these observed 

differences were not statistically 

significant. In the United States, 

there were no statistically significant 

differences in prediabetes prevalence 

among non-Hispanic black adults 

(43.3%), non-Hispanic white adults, 

and Hispanic adults. Prevalence was 

higher among Mexican-American 

adults (45.0%) compared with 

non-Hispanic white adults in the 

United States.

Discussion

The prevalence of total diabetes 

among adults in Los Angeles County 

increased from 10.5% in 1999–2006 to 

14.4% in 2007–2014. A similar increase 

in total diabetes prevalence occurred 

among adults in the United States. 

Among adults with diabetes in Los 

Angeles County in 2007–2014, 29.9% 

had undiagnosed diabetes and among 

U.S. adults with diabetes, 30.6% had 

undiagnosed diabetes. In 2007–2014, the 

prevalence of prediabetes was 40.2% in 

Los Angeles County and 42.2% in the 

United States. No significant differences 

in the overall prevalence of diagnosed 

diabetes, undiagnosed diabetes, total 

diabetes, or prediabetes were detected 

between Los Angeles County and 

the United States in 1999–2006 or 

2007–2014.

The prevalence of diagnosed 

diabetes, total diabetes, and prediabetes 

increased with age in both Los Angeles 

County and the United States. 

The prevalence of total diabetes was 

higher among non-Hispanic black adults, 

Hispanic adults, and Mexican-American 

adults than among non-Hispanic white 

adults in both Los Angeles County and 

the United States in 2007–2014.

Non-Hispanic black and MexicanAmerican adults had a pattern of higher 

prevalence of diagnosed diabetes and 

prediabetes compared with non-Hispanic 

white adults in both Los Angeles County 

and the United States.

The NHANES sample design 

and physical exam and laboratory 

components allowed estimation of health 

measures, such as the prevalence of 

diagnosed and undiagnosed diabetes and 

prediabetes, for the Los Angeles County 

population. The smaller sample size for 

Los Angeles County was further reduced 

because only the fasting half-sample had 

plasma fasting glucose levels available for 

analysis. Although 8 years of data were 

combined in order to increase sample 

sizes, statistical power was still reduced 

for detecting small but potentially 

meaningful differences in prevalence 

among subgroups. For example, 

the prevalence of total diabetes and 

diagnosed diabetes, but not undiagnosed 

diabetes, increased significantly in 

the United States from 1999–2006 to 

2007–2014; there was a similar pattern 

in Los Angeles County, but a significant 

difference in prevalence was detected for 

total diabetes only. Statistical testing of 

differences in prevalence between Los 

Angeles County and the United States 

for subgroups was not presented, but 

prevalence estimates for the United States 

were presented for reference.

Community-based lifestyle 

change programs (18,19), diabetes 

self-management education (20,21), 

and team-based medication therapy 

management (22) are some approaches 

to the prevention of diabetes and its 

related complications. Monitoring trends 

in diagnosed diabetes, undiagnosed 

diabetes, total diabetes, and prediabetes 

among adults in Los Angeles County 

and the United States may inform the 

development and implementation of 

targeted prevention and control efforts at 

the national and local levels.
National Health Statistics Reports  Number 123  April 19, 2019 Page 5

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Page 6 National Health Statistics Reports  Number 123  April 19, 2019

Table 1. Age-adjusted and crude prevalence of diagnosed, undiagnosed, and total diabetes, and prediabetes among adults aged 20 and 

over: Los Angeles County and the United States, 1999–2006 and 2007–2014

Characteristic

Los Angeles County United States

1999–2006 2007–2014 1999–2006 2007–2014

Sample size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342 456 7,554 9,596

Age-adjusted prevalence Percent (95% confidence interval)

Total diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.5 (7.5, 14.2) 1

14.4 (11.3, 18.1) 10.7 (9.7, 11.7) 112.4 (11.4, 13.5)

Diagnosed diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 (4.9, 10.8) 10.2 (6.7, 14.6) 7.2 (6.4, 8.0) 1

8.6 (7.7, 9.5)

Undiagnosed diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3.0 (1.1, 6.4) 4.3 (2.5, 6.8) 3.5 (3.0, 4.1) 3.8 (3.4, 4.3)

Prediabetes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37.3 (30.9, 44.1) 40.2 (35.1, 45.6) 37.2 (35.2, 39.3) 1

42.4 (40.9, 44.0)

Crude prevalence

Total diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.5 (6.6, 13.0) 14.0 (10.4, 18.3) 10.6 (9.7, 11.6) 1

13.1 (12.1, 14.1)

Diagnosed diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.8 (4.5, 9.9) 9.9 (6.3, 14.6) 7.1 (6.4, 7.9) 1

9.1 (8.2, 10.0)

Undiagnosed diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6 (1.1, 5.2) 4.1 (2.4, 6.5) 3.5 (3.0, 4.0) 4.0 (3.6, 4.5)

Prediabetes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36.1 (29.8, 42.7) 39.7 (33.5, 46.1) 37.2 (35.0, 39.4) 1

43.0 (41.4, 44.7)

1

Significantly different from 1999–2006.

2

Estimate does not meet NCHS standards of reliability.

NOTES: CI is confidence interval. Prevalence estimates were age adjusted by the direct method to the projected 2000 U.S. census population using the age groups 20–39, 40–59, and 60 and over.

SOURCE: NCHS, National Health and Nutrition Examination Survey, 1999–2014.
National Health Statistics Reports  Number 123  April 19, 2019 Page 7

Table 2. Age-adjusted prevalence of diagnosed diabetes, total diabetes, and prediabetes among adults aged 20 years and older by age, sex, 

and race and Hispanic origin: Los Angeles County and United States, 2007–2014

Characteristic

Los Angeles County United States

Sample size

Prevalence percentage 

(95% confidence interval) Sample size

Prevalence percentage 

(95% confidence interval)

Diagnosed diabetes

Age:

20–39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 1

0.3 (0.0, 1.8) 3,094 11.5 (1.1, 2.1)

40–59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 14.9 (8.4, 23.9) 3,296 9.4 (8.1, 10.8)

60 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 19.4 (11.4, 29.9) 3,206 19.3 (17.2, 21.5)

Sex:

Men. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 13.1 (7.9, 20.2) 4,654 9.1 (8.1, 10.3)

Women. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 7.5 (4.1, 12.3) 4,942 8.1 (7.1, 9.2)

Race and Hispanic origin:

Non-Hispanic white. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 2,3

5.5 (1.3, 14.5) 4,302 7.1 (6.1, 8.3)

Non-Hispanic black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 2,3

7.7 (0.5, 29.6) 1,834 413.3 (11.8, 15.0)

Hispanic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 10.3 (6.8, 14.7) 2,494 4

12.4 (11.1, 13.7)

Mexican American5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 11.6 (7.2, 17.2) 1,468 4

13.4 (11.7, 15.2)

Total diabetes

Age:

20–39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 1

1.1 (0.2, 3.6) 3,094 13.1 (2.4, 3.9)

40–59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 19.8 (12.5, 29.0) 3,296 13.5 (11.8, 15.3)

60 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 28.6 (20.2, 38.3) 3,206 26.6 (24.6, 28.8)

Sex:

Men. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 19.0 (13.4, 25.6) 4,654 14.0 (12.6, 15.4)

Women . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 6

10.4 (6.5, 15.6) 4,942 611.0 (9.9, 12.1)

Race and Hispanic origin:

Non-Hispanic white. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 2,3

6.4 (1.9, 15.2) 4,302 10.3 (9.1, 11.6)

Non-Hispanic black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 2,3,4

17.9 (4.1, 43.2) 1,834 418.7 (16.7, 20.7)

Hispanic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 4

14.9 (10.3, 20.7) 2,494 418.2 (16.3, 20.3)

Mexican American5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 4

16.5 (10.3, 24.3) 1,468 419.7 (17.2, 22.3)

Prediabetes

Age:

20–39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 1

23.5 (16.4, 31.9) 3,094 133.2 (30.8, 35.7)

40–59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 46.7 (35.7, 57.9) 3,296 46.5 (44.2, 48.9)

60 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 58.5 (47.0, 69.3) 3,206 51.7 (48.9, 54.4)

Sex:

Men. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 42.0 (35.3, 48.9) 4,654 48.2 (45.8, 50.7)

Women . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 38.0 (29.7, 47.0) 4,942 6

36.5 (34.8, 38.2)

Race and Hispanic origin:

Non-Hispanic white. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 2,3

33.3 (15.2, 56.1) 4,302 41.7 (39.6, 43.9)

Non-Hispanic black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 2,3

40.6 (14.6, 71.3) 1,834 43.3 (40.7, 45.9)

Hispanic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 41.2 (35.1, 47.5) 2,494 43.9 (41.8, 46.2)

Mexican American5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 42.7 (34.1, 51.7) 1,468 4

45.0 (42.3, 47.8)

1

Significantly increasing trend across age categories.

2

Estimate does not meet NCHS standards of reliability.

3

Standard error based on less than 8 degrees of freedom.

4

Significantly different from non-Hispanic white adults.

5

Hispanic includes Mexican American.

6

Significantly different from men.

NOTES: CI is confidence interval. Prevalence estimates were age adjusted by the direct method to the projected 2000 U.S. census population using the age groups 20–39, 40–59, and 60 and over.

SOURCE: NCHS, National Health and Nutrition Examination Survey, 1999–2014.
For more NCHS NHSRs, visit: 

https://www.cdc.gov/nchs/products/nhsr.htm.

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Internet: https://www.cdc.gov/nchs • Online request form: https://www.cdc.gov/info

DHHS Publication No. 2019–1250 • CS303185

Suggested citation

Hales CM, Carroll MD, Kuo T, Simon PA. 

Diabetes and prediabetes among adults in 

Los Angeles County and the United States, 

1999–2006 and 2007–2014. National Health 

Statistics Reports; no 123. Hyattsville, MD: 

National Center for Health Statistics. 2019.

Copyright information

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or copied without permission; citation as to 

source, however, is appreciated.

National Center for Health Statistics

Jennifer H. Madans, Ph.D., Acting Director

Amy M. Branum, Ph.D., Acting Associate 

Director for Science

Division of Health and Nutrition 

Examination Surveys

Kathryn S. Porter, M.D., M.S., Director

Ryne Paulose-Ram, M.A., Ph.D., Associate 

Director for Science

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National Health Statistics Reports  Number 123  April 19, 2019