Burden of Chronic Kidney Disease by State from 2002 to 2016

To date, there has not been a detailed quantitative analysis of the change in burden of CKD. Benjamin Bowe, MPH, and colleagues recently conducted an analysis of data from the 2016 Global Burden of Disease study in the United States; in addition, the researchers examined data on CKD from 2002 to 2016 at the state level. The analysis was designed to (1) describe the change in the burden of CKD in the United States from 2002 to 2016, (2) characterize the factors associated with change in the CKD burden, and (3) examine the ways sociodemographic progress has shaped the burden of CKD. Results were reported online in JAMA Network Open [doi:109.1001/jamanetworkopen.2018.4412].

The primary outcomes and measures of interest were disability-adjusted life years (DALYs) and death due to CKD.

CKD DALYs in the United States increased from 1,269,049 in 2002 (95% uncertainty interval [UI], 1,154,521-1,387,008) to 1 935 954 in 2016 (95% UI, 1,747,356-2,124,795), for a 52.6% increase over the 15-year study period. There was an increase in DALY rates of 35.9%, from 441 per 100,000 population (95% UI, 401-482/100,000 population) in 2002 to 600 per 100,000 population (95% UI, 541-658/100,000 population) in 2016.

DALY rates standardized by age increased from 371 per 100,000 population (95% UI, 336-406/100,000 population) in 2002 to 440 per 100,000 population (95% UI, 395-485/100,000 population) in 2016, an increase of 18.6%. An analysis of the change in age-standardized DALY rates by four causes of CKD (diabetes, hypertension, glomerulonephritis, and other) demonstrated an increase in the age-standardized DALY rate of CKD due to diabetes (21.8%), CKD due to hypertension (22.0%), CKD due to glomerulonephritis (10.4%), and CKD due to other causes (10.3%).

In the overall United States, there was an increase in deaths due to CKD from 52,127 (95% UI, 51,082-53,076) in 2002 to 82,539 (95% UI, 80,298-84,652). In 2002, there were 18 deaths from CKD per 100,000 population; in 2016, there were 26 deaths per CKD per 100,000 population, an increase of 41.1%. During the 15-year study period, the age-standardized death rate increased by 17.9%, from 14 per 100 000 population to 16 per 100 000 population. The age-standardized death rates for CKD due to diabetes increased by 20.0%, hypertension by 19.8%, glomerulonephritis by 11.1%, and other causes by 11.0%.

In analyses of data at the state level, the states with the highest age-standardized DALY rates per 100,000 in 2016 were (in descending order): Mississippi (697); Louisiana (681); Alabama (604); West Virginia (587), Georgia (560); Arkansas (553); South Carolina (550); Kentucky (550); Indiana (515); and North Carolina (515). The states with the lowest age-standardized DALY rates per 100,000 population were (in ascending order): Vermont (321); Washington (328); Colorado (331); Montana (333); Oregon (342); Wyoming (343); New Hampshire (343); Iowa (349); Rhode Island (355); and Connecticut (356). The state with the highest burden, Mississippi, had twice the age-standardized CKD DALY rate comparted with Vermont (the state with the lowest burden).

All states exhibited an increase in CKD DALYs from 2002 to 2016, but there was a difference in the magnitude of the increase, ranging from 32.9% in Oklahoma to 6.3% in Nevada. The states with the largest increase in age-standardized CKD DALY rates were (in descending order): Oklahoma (32.9%); West Virginia (31.3%); Texas (30.9%); New Mexico (30.7%); Iowa (30.1%); Washington (28.5%); Idaho (28.2%); Tennessee (27.9%); Arkansas (27.8%); and Kentucky (26.3%). Those with the least increase in age-standardized CKD DALY rates were (in ascending order): Nevada (6.3%); New Jersey (6.8%); Massachusetts (8.8%): Maryland (9.3%); Illinois (10.4%); New York (10.8%); Connecticut (11.3%); Pennsylvania (12.0%); Georgia (12.7%); and Colorado (13.6%).

There was variation in age-standardized death rates among states in 2016. Rates were 2.4-fold higher in Louisiana compared with Vermont (28/100,000 population vs 11/100,000 population, respectively). From 2002 to 2016, the rate of change in age-standardized deaths varied among states and ranged from 41.0% in Iowa to –2.8% in Nevada.

During the study period, there was a 52.6% increase in DALYs in the United States, of which 40.3% was attributable to increased risk exposure, 32.3% to aging, and 27.4% to population growth. The rates increased by 18.6% where increases in metabolic, and to a lesser extent dietary, risk factors contributed 93.8% and 5.23% of the change, respectively.

Diabetic CKD was the primary contributor to the 26.8% increased probability of death due to CKD among those 20 to 54 years of age; among those 55 to 89 years of age, the probability of death due to CKD increased by 25.6% and was driven by CKD due to diabetes and decreased probability of death from causes other than CKD. Improvement in sociodemographic development was coupled with an increase in age-standardized CKD DALY rates that occurred at a faster pace than that of other noncommunicable diseases in the United States.

The researchers cited some limitations to the study, including limiting analyses to state-level data; attributing CKD to a single cause; and restricting analysis in the change in probability of death to persons >20 years of age while not restricting all other analyses to the adult population.

“Our study revealed that, from 2002 to 2016, the burden of CKD in the United States increased and was variable among states. This increase may be associated with increased risk exposure and demographic expansion leading to increased probability of death from CKD, especially among young adults. The findings suggest that an effort to target the reduction of CKD through greater attention to metabolic and dietary risks, especially among younger adults, is necessary,” the researchers said.