Table 2 Data extraction of the 10 studies in the systematic review with a cross-sectional study design
From: Adverse Effects of fine particulate matter on human kidney functioning: a systematic review
Authors (year) (type of study) | Exposure Estimate | Study Population | Main Findings |
|---|---|---|---|
Zhao et al. (2020) [15] (cross-sectional study) | The mean ± SD exposure level to PM2.5 during the whole pregnancy was 52.24 ± 2.93 µg/m³ (IQR value: 3.90 µg/m³), exceeding the air quality guidelines set by WHO. The mean ± SD black carbon exposure level during the entire pregnancy was 3.56 ± 0.28 µg/m³. | Healthy pregnant women (n = 10,052) in Shanghai (China) with a mean ± SD gestational age of 35.64 ± 1.74 weeks at renal function testing. Study period: Jan. 2014 – Dec. 2015 | An IQR increment in PM2.5 was positively associated (p < 0.01) with serum UN in the second and third trimester, and during the whole pregnancy. For serum UA, an IQR increment in PM2.5 could only be associated with the first trimester, but not the second or third trimester or during the whole pregnancy. Negative significant associations were demonstrated between eGFR and an IQR increment in PM2.5 and black carbon for the first and third trimester of pregnancy as well as the whole pregnancy (p < 0.01). |
Chuang et al. (2015) [28] (cross-sectional study) | Participants were stratified in low (office workers) and high (welders) PM2.5 exposure with mean ± SD PM2.5 exposure levels of 27.4 ± 16.2 µg/m³ and 50.3 ± 32.8 µg/m³, respectively. The average PM2.5 concentrations of both office workers and welders exceeded the WHO air quality guidelines. | Welders with a mean ± SD age of 51.0 ± 9.7 years (n = 66) and office workers with a mean ± SD age of 48.2 ± 15.3 years (n = 12) working in a shipyard in southern Taiwan. Study period: 1 week | Levels of urinary KIM-1 and NGAL adjusted for urinary creatinine were significantly increased in welders post-exposure (p < 0.05), but no changes were observed in office workers post-exposure. |
Weaver et al. (2019) [29] (cross-sectional study) | The mean ± SD 1-year and 3-year PM2.5 exposure levels were 12.2 ± 0.6 µg/m³ and 12.4 ± 0.5 µg/m³ respectively. The average PM2.5 concentration exceeded the WHO air quality guidelines. | African-Americans participating in the Jackson Heart Study (n = 5,090) with a mean ± SD age of 55.4 ± 12.8 years. Study period: 2000 – 2004 | Inverse associations of 1-year and 3-year PM2.5 exposure could be observed with UACR (p < 0.05), indicating better a renal function with increasing PM2.5 exposure. |
Bernatsky et al. (2011) [33] (cross-sectional study) | The average ± SD daily PM2.5 exposure was 10.0 ± 7.8 µg/m³ (range 1.1 – 54.9 µg/m³) PM2.5, not exceeding the newly set WHO air quality guidelines. | Patients registered at the Lupus Clinic in Montreal (n = 237) with a mean ± SD age of 41.2 ± 15.5 years at the first visit. Study period: Jan. 2000 – Sept. 2007 | No relationship between PM2.5 and SLEDAI-2 K scores could be demonstrated. Anti-dsDNA and urinary renal casts were significantly associated with PM2.5 exposure before the clinical visit(s) (p < 0.05); there was suggestive evidence of some association between anti-dsDNA and PM2.5 levels averaged over 10 days, although non-significant. |
Chen et al. (2018) [38] (cross-sectional study) | Annual average ± SD PM2.5 concentration and PM2.5 absorbance amounted to 24.3 ± 3.9 µg/m³ and 1.8 ± 0.3 × 10−5/m, respectively. An IQR of 4.1 µg/m³ and 0.4 × 10−5/m was identified for PM2.5 exposure and PM2.5 absorbance, respectively. The average PM2.5 concentration exceeded the WHO air quality guidelines. | Elderly Taiwanese population with a mean ± SD age of 74.2 ± 6.5 years (n = 8,479). Of the total participants, 27.8% had CKD stage III to V (eGFR < 60 mL/min/1.73 m²). Study period: Mar. 2009 – Aug. 2009 | A lower eGFR could be associated with one-year PM2.5 absorbance, but not PM2.5 exposure. For each IQR increment of PM2.5 absorbance proteinuria was non-significantly increased; no difference could be demonstrated for an IQR increment of PM2.5 exposure. A higher risk for CKD prevalence was demonstrated for PM2.5 and PM2.5 absorbance; the risk of CKD progression was elevated for PM2.5 absorbance. |
Wang et al. (2020) [41] (cross-sectional study) | The mean ± SD PM2.5 exposure level was 61.22 ± 0.50 µg/m³, far exceeding the WHO air quality guidelines. | Hospitalized Chinese patients with a mean ± SD age of 60.37 ± 14.48 years (n = 3,622). Study period: Oct. 2014 – May 2015 | No significant association could be shown between eGFR decline or CKD and PM2.5 exposure. |
Yang et al. (2017) [42] (cross-sectional study) | The annual average ± SD PM2.5 exposure level was 26.64 ± 5.01 µg/m³, with an IQR of 5.67 µg/m³. The average PM2.5 concentration exceeded the WHO air quality guidelines. The annual average ± SD PM2.5 absorbance was 1.94 ± 0.39 × 10−5/m, with an IQR of 0.48 × 10−5/m. | Taiwanese citizens over 30 years of age with a mean ± SD age of 53.65 ± 10.37 years (n = 21,656). Of the total participants, 10.3% had CKD based on eGFR < 60 mL/min/1.73 m². Study period: 2007 – 2009 | An IQR increment of PM2.5 exposure and/or PM2.5 absorbance indicated no association(s) with a lower eGFR or CKD. |
Liang et al. (2021)[45] (nation-wide cross-sectional study) | The median (IQR) PM2.5 concentration amounted to 44.63 (18.65) µg/m³. The median exceeded by far the standard air quality guidelines set by the WHO. | Adults (>18 years old) residing in urban and rural areas in China (n = 47,086). The average age ± SD for participants with CKD (n = 4,790) and with no indications of CKD (n = 42,116) was 55.73 ± 16.37 and 48.90 ± 14.90 years, respectively. Study period: 2007 – 2010 | Results indicated that elevated PM2.5 concentrations were significantly associated with increased odds of CKD prevalence. The results showed a stronger increase in odds for CKD in rural areas compared to urban areas (pinteraction < 0.001). |
Li G. et al.(2021)[48] (cross-sectional study) | The mean ± SD 2-year PM2.5 concentration was 57.4 ± 15.6 µg/m³ (range: 31.3 to 87.5 µg/m³). The exposure levels exceeded by far the air quality guidelines set by the WHO. | Chinese adults (≥18 years; n = 47,204) with a mean ± SD age of 49.71 ± 15.54 and 49.47 ± 14.83 years for a mean ≤2 and >2-year PM2.5 concentration, respectively. Study period: Sept. 2009 – Sept. 2010 | Each 10 µg/m³ increase in PM2.5 level was positively associated with CKD prevalence and albuminuria (p < 0.05). A significant difference was observed between urban and rural areas in CKD prevalence (pinteraction = 0.004). |
Kuźma et al. (2021)[49] (retrospective cross-sectional study) | The median (IQR) PM2.5 concentration was 10.9 (15.9) µg/m³ during the entire study period. The PM2.5 levels exceeded the air quality guidelines set by the WHO. | Adults ≥18 years in China (n = 3,554) with a median age of 66 years. Study period: 2007 – 2016 | With an increase in annual PM2.5 concentration, an increase in odds of CKD could be observed (p < 0.05). Furthermore, an IQR increase in weekly PM2.5 lead to a reduction in eGFR (p < 0.05). |