Estimation of chronic kidney disease incidence from prevalence and mortality data in American Indians with type 2 diabetes

<div><p>The objective was to estimate chronic kidney disease (CKD) incidence rates from prevalence and mortality data, and compare the estimates with observed (true) incidence rates in a well-characterized population with diabetes. Pima Indians aged 20 years and older with type 2 diabetes were followed from 1982 through 2007. CKD was defined by estimated GFR (eGFR) <60 ml/min/1.72 m² or albumin-to-creatinine ratio (ACR) ≥30 mg/g. True CKD incidence and mortality rates were computed for the whole study period, and prevalence for the intervals 1982–1994 and 1995–2007. Estimated age-sex stratified CKD incidence rates were computed using illness-death models of the observed prevalences, and of the whole-period mortality rate ratio of CKD to non-CKD persons. Among 1201 participants, 616 incident events of CKD occurred during a median follow-up of 5.6 years. Observed CKD prevalence was 56.9% (95%CI 53.7–60.0) and 48.0% (95%CI 45.2–50.8) in women; 54.0% (95%CI 49.9–58.1) and 49.6% (95%CI 46.0–53.3) in men, across the two periods. Mortality rate was 2.5 (95%CI 1.9–3.3) times as high in women with CKD and 1.6 (95%CI 1.3–2.1) times as high in men with CKD, compared to women or men without CKD. In women, estimated CKD incidence increased linearly from 25.6 (95%CI 4.2–53.0) to 128.6 (95%CI 77.1–196.6) with each 5-year age group up to 69 years, and to 99.8 (95%CI 38.7–204.7) at age ≥70. In men, estimated CKD incidence increased form 28.5 (95%CI 3.8–71.2) at age 20–24 years to 118.7 (95%CI 23.6–336.7) at age ≥70. Age-sex-stratified estimated incidence reflected the magnitude and directional trend of the true incidence and were similar to the true incidence rates (p>0.05 for difference) except for age 20–24 in women (p = 0.008) and age 25–29 in men (p = 0.002). In conclusion, the estimated and observed incidence rates of CKD agree well over 25 years of observation in this well characterized population with type 2 diabetes.</p></div

Age- and sex-specific observed (true) and estimated incidence rate of chronic kidney disease in the cohort with type 2 diabetes during the study period (1982–2007).

<p>CI, confidence interval.</p

Illness-death model with transition rates (<i>i</i>, <i>r</i>, <i>m</i>_<i>0</i>, <i>m</i>_<i>1</i>).

<p>CKD, chronic kidney disease; T2DM, type 2 diabetes mellitus.</p

Characteristics of the study population with type 2 diabetes for the prevalence periods.

<p>Characteristics of the study population with type 2 diabetes for the prevalence periods.</p

Age- stratified observed and estimated incidence rates of CKD in women (above) and men (below) during the period 1982–2007.

<p>The asterisk (*) indicates significant difference between true and estimated CKD incidence.</p

Risk Factors Amenable to Primary Prevention of Type 2 Diabetes Among Disaggregated Racial and Ethnic Subgroups in the United States

Race and ethnicity data disaggregated into detailed subgroups may reveal pronounced heterogeneity in diabetes risk factors. We therefore used disaggregated data to examine the prevalence of type 2 diabetes risk factors related to lifestyle behaviors and barriers to preventive care, among adults in the United States. We conducted a pooled cross-sectional study of 3,437,640 adults aged ≥18 in the United States without diagnosed diabetes from the Behavioral Risk Factor Surveillance System (2013–2021). Self-reported race and ethnicity included: Hispanic (Cuban, Mexican, Puerto Rican, Other Hispanic), Non-Hispanic (NH) American Indian/Alaska Native, NH Asian (Chinese, Filipino, Indian, Japanese, Korean, Vietnamese, Other Asian), NH Black, NH Pacific Islander (Guamanian/Chamorro, Native Hawaiian, Samoan, Other Pacific Islander), NH White, NH Multiracial, NH Other. Risk factors included: current smoking, hypertension, overweight or obesity, physical inactivity, being uninsured, not having a primary care doctor, healthcare cost concerns, and no physical exam in the past 12 months. Prevalence of hypertension, lifestyle factors and barriers to preventive care showed substantial heterogeneity among both aggregated, self-identified racial and ethnic groups and disaggregated subgroups. For example, the prevalence of overweight or obesity ranged from 50.8% (95% confidence interval [CI], 49.1–52.5) among Chinese adults to 79.8% (73.5–84.9) among Samoan adults. Prevalence of being uninsured among Hispanic subgroups ranged from 11.4% (10.9–11.9) among Puerto Rican adults to 33.0% (32.5–33.5) among Mexican adults. These findings underscore the importance of using disaggregated race and ethnicity data to accurately characterize disparities in type 2 diabetes risk factors and access to care.</p

The Cost-Effectiveness of Anemia Treatment for Persons with Chronic Kidney Disease

<div><p>Background</p><p>Although major guidelines uniformly recommend iron supplementation and erythropoietin stimulating agents (ESAs) for managing chronic anemia in persons with chronic kidney disease (CKD), there are differences in the recommended hemoglobin (Hb) treatment target and no guidelines consider the costs or cost-effectiveness of treatment. In this study, we explored the most cost-effective Hb target for anemia treatment in persons with CKD stages 3–4.</p><p>Methods and Findings</p><p>The CKD Health Policy Model was populated with a synthetic cohort of persons over age 30 with prevalent CKD stages 3–4 (i.e., not on dialysis) and anemia created from the 1999–2010 National Health and Nutrition Examination Survey. Incremental cost-effectiveness ratios (ICERs), computed as incremental cost divided by incremental quality adjusted life years (QALYs), were assessed for Hb targets of 10 g/dl to 13 g/dl at 0.5 g/dl increments. Targeting a Hb of 10 g/dl resulted in an ICER of $32,111 compared with no treatment and targeting a Hb of 10.5 g/dl resulted in an ICER of$32,475 compared with a Hb target of 10 g/dl. QALYs increased to 4.63 for a Hb target of 10 g/dl and to 4.75 for a target of 10.5 g/dl or 11 g/dl. Any treatment target above 11 g/dl increased medical costs and decreased QALYs.</p><p>Conclusions</p><p>In persons over age 30 with CKD stages 3–4, anemia treatment is most cost-effective when targeting a Hb level of 10.5 g/dl. This study provides important information for framing guidelines related to treatment of anemia in persons with CKD.</p></div

One-way sensitivity analyses of cost-effectiveness for different anemia treatment targets.

<p>One-way sensitivity analyses of cost-effectiveness for different anemia treatment targets.</p

Incremental cost-effectiveness as a function of anemia treatment targets in persons with CKD stages 3–4.

<p>Incremental cost-effectiveness as a function of anemia treatment targets in persons with CKD stages 3–4.</p

Quality adjusted life years as a function of Hb treatment targets illustrates an inverted U-shaped relationship in persons with CKD stages 3–4.

<p>ESA, erythropoietin stimulating agents; Hb, hemoglobin.</p