Table 3.

Association of annual average PM2.5 with incident CKD in participants with eGFR ≥60 ml/min per 1.73 m2 at baseline

CharacteristicNumber of Eligible ParticipantsNumber of CKD EventsPerson-YearsCKD Incidence per 1000 Person-Years (95% CI)Incident CKD, HR (95% CI)P ValueInteraction P Value
Overall
 Model 1a10,3022816158,19917.8 (17.2 to 18.5)1.07 (1.03 to 1.11)0.001
 Model 2b1.05 (1.01 to 1.10)0.03
Sex
 Male4518135965,51120.7 (19.7 to 21.9)1.04 (0.98 to 1.10)0.200.54
 Female5784145792,68715.7 (14.9 to 16.5)1.10 (1.00 to 1.21)0.05
Age, yr
 <6563851559104,50114.9 (14.2 to 15.7)1.03 (0.97 to 1.10)0.310.63
 ≥653917125753,69723.4 (22.2 to 24.7)1.09 (0.99 to 1.20)0.07
History of diabetes
 No86232105136,22315.5 (14.8 to 16.1)1.08 (1.01 to 1.16)0.020.13
 Yes163569821,38732.6 (30.3 to 35.2)0.98 (0.89 to 1.08)0.73
History of hypertension
 No5536117789,27813.2 (12.5 to 14.0)1.02 (0.96 to 1.09)0.550.15
 Yes4726162968,33923.8 (22.7 to 25.0)1.09 (1.02 to 1.16)0.02
Income above medianc
 No5581161681,92619.7 (18.8 to 20.7)1.05 (0.98 to 1.12)0.210.58
 Yes4253107269,60315.4 (14.5 to 16.4)1.06 (0.99 to 1.14)0.07
  • PM2.5, particulate matter <2.5 μm in aerodynamic diameter; HR, hazard ratio.

  • a Model 1: sex, age, race, neighborhood socioeconomic score, family income, education level.

  • b Model 2: model 1 plus body mass index, diabetes mellitus, hypertension, systolic BP, composite cardiovascular disease, cigarette smoking, eGFR, urinary albumin-creatinine ratio, C-reactive protein, temperature. Model 2 adjustment used for stratified analyses. Analyses performed per 1-μg/m3 higher PM2.5.

  • c Median income was $16,000–$24,999 for Jackson, $25,000–$34,999 for Washington County, and $35,000–$49,999 for Forsyth County and Minneapolis.